diff --git a/.github/workflows/docker-antithesis.yml b/.github/workflows/docker-antithesis.yml
index 40de0bd0a..84f5541a3 100644
--- a/.github/workflows/docker-antithesis.yml
+++ b/.github/workflows/docker-antithesis.yml
@@ -17,7 +17,7 @@ jobs:
     build-docker:
         runs-on: ubuntu-22.04
         steps:
-            - uses: actions/checkout@v2
+            - uses: actions/checkout@v3
             - name: Update Rust
               run: rustup update stable
             - name: Dockerhub login
diff --git a/.github/workflows/docker.yml b/.github/workflows/docker.yml
index 8d72319c6..13b841169 100644
--- a/.github/workflows/docker.yml
+++ b/.github/workflows/docker.yml
@@ -22,7 +22,7 @@ jobs:
     # `unstable`, but for now we keep the two parts of the version separate for backwards
     # compatibility.
     extract-version:
-        runs-on: ubuntu-18.04
+        runs-on: ubuntu-22.04
         steps:
             - name: Extract version (if stable)
               if: github.event.ref == 'refs/heads/stable'
@@ -44,7 +44,7 @@ jobs:
             VERSION_SUFFIX: ${{ env.VERSION_SUFFIX }}
     build-docker-single-arch:
         name: build-docker-${{ matrix.binary }}
-        runs-on: ubuntu-18.04
+        runs-on: ubuntu-22.04
         strategy:
             matrix:
                 binary: [aarch64,
@@ -61,7 +61,7 @@ jobs:
             VERSION: ${{ needs.extract-version.outputs.VERSION }}
             VERSION_SUFFIX: ${{ needs.extract-version.outputs.VERSION_SUFFIX }}
         steps:
-            - uses: actions/checkout@v2
+            - uses: actions/checkout@v3
             - name: Update Rust
               run: rustup update stable
             - name: Dockerhub login
@@ -102,7 +102,7 @@ jobs:
                       --push
     build-docker-multiarch:
         name: build-docker-multiarch${{ matrix.modernity }}
-        runs-on: ubuntu-18.04
+        runs-on: ubuntu-22.04
         needs: [build-docker-single-arch, extract-version]
         strategy:
             matrix:
@@ -123,13 +123,13 @@ jobs:
                       --amend ${IMAGE_NAME}:${VERSION}-amd64${VERSION_SUFFIX}${{ matrix.modernity }};
                   docker manifest push ${IMAGE_NAME}:${VERSION}${VERSION_SUFFIX}${{ matrix.modernity }}
     build-docker-lcli:
-        runs-on: ubuntu-18.04
+        runs-on: ubuntu-22.04
         needs: [extract-version]
         env:
             VERSION: ${{ needs.extract-version.outputs.VERSION }}
             VERSION_SUFFIX: ${{ needs.extract-version.outputs.VERSION_SUFFIX }}
         steps:
-            - uses: actions/checkout@v2
+            - uses: actions/checkout@v3
             - name: Dockerhub login
               run: |
                   echo "${DOCKER_PASSWORD}" | docker login --username ${DOCKER_USERNAME} --password-stdin
diff --git a/.github/workflows/linkcheck.yml b/.github/workflows/linkcheck.yml
index 30a891feb..4d4e92ae1 100644
--- a/.github/workflows/linkcheck.yml
+++ b/.github/workflows/linkcheck.yml
@@ -15,7 +15,7 @@ jobs:
 
     steps:
       - name: Checkout code
-        uses: actions/checkout@v2
+        uses: actions/checkout@v3
 
       - name: Create docker network
         run: docker network create book
diff --git a/.github/workflows/local-testnet.yml b/.github/workflows/local-testnet.yml
index 170bd9e21..b916ffee6 100644
--- a/.github/workflows/local-testnet.yml
+++ b/.github/workflows/local-testnet.yml
@@ -12,11 +12,11 @@ jobs:
     strategy:
       matrix:
         os:
-          - ubuntu-18.04
-          - macos-latest
+          - ubuntu-22.04
+          - macos-12
     runs-on: ${{ matrix.os }}
     steps:
-      - uses: actions/checkout@v1
+      - uses: actions/checkout@v3
 
       - name: Get latest version of stable Rust
         run: rustup update stable
@@ -28,7 +28,7 @@ jobs:
         run: npm install ganache@latest --global
 
       # https://github.com/actions/cache/blob/main/examples.md#rust---cargo
-      - uses: actions/cache@v2
+      - uses: actions/cache@v3
         id: cache-cargo
         with:
           path: |
diff --git a/.github/workflows/publish-crate.yml b/.github/workflows/publish-crate.yml
index a7fda90f7..736057f78 100644
--- a/.github/workflows/publish-crate.yml
+++ b/.github/workflows/publish-crate.yml
@@ -19,7 +19,7 @@ jobs:
         runs-on: ubuntu-latest
         steps:
             - name: Extract tag
-              run: echo "::set-output name=TAG::$(echo ${GITHUB_REF#refs/tags/})"
+              run: echo "TAG=$(echo ${GITHUB_REF#refs/tags/})" >> $GITHUB_OUTPUT
               id: extract_tag
         outputs:
             TAG: ${{ steps.extract_tag.outputs.TAG }}
@@ -30,7 +30,7 @@ jobs:
         env:
             TAG: ${{ needs.extract-tag.outputs.TAG }}
         steps:
-            - uses: actions/checkout@v2
+            - uses: actions/checkout@v3
             - name: Update Rust
               run: rustup update stable
             - name: Cargo login
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 6edb1f76c..957d016dc 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -16,7 +16,7 @@ jobs:
         runs-on: ubuntu-latest
         steps:
             - name: Extract version
-              run: echo "::set-output name=VERSION::$(echo ${GITHUB_REF#refs/tags/})"
+              run: echo "VERSION=$(echo ${GITHUB_REF#refs/tags/})" >> $GITHUB_OUTPUT
               id: extract_version
         outputs:
             VERSION: ${{ steps.extract_version.outputs.VERSION }}
@@ -62,7 +62,7 @@ jobs:
         needs: extract-version
         steps:
             - name: Checkout sources
-              uses: actions/checkout@v2
+              uses: actions/checkout@v3
             - name: Build toolchain
               uses: actions-rs/toolchain@v1
               with:
@@ -199,7 +199,7 @@ jobs:
         steps:
             # This is necessary for generating the changelog. It has to come before "Download Artifacts" or else it deletes the artifacts.
             - name: Checkout sources
-              uses: actions/checkout@v2
+              uses: actions/checkout@v3
               with:
                   fetch-depth: 0
 
@@ -216,7 +216,7 @@ jobs:
 
             - name: Generate Full Changelog
               id: changelog
-              run: echo "::set-output name=CHANGELOG::$(git log --pretty=format:"- %s" $(git describe --tags --abbrev=0 ${{ env.VERSION }}^)..${{ env.VERSION }})"
+              run: echo "CHANGELOG=$(git log --pretty=format:"- %s" $(git describe --tags --abbrev=0 ${{ env.VERSION }}^)..${{ env.VERSION }})" >> $GITHUB_OUTPUT
 
             - name: Create Release Draft
               env:
diff --git a/.github/workflows/test-suite.yml b/.github/workflows/test-suite.yml
index a3e9625b5..d536869e4 100644
--- a/.github/workflows/test-suite.yml
+++ b/.github/workflows/test-suite.yml
@@ -24,12 +24,12 @@ jobs:
   extract-msrv:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v3
     - name: Extract Minimum Supported Rust Version (MSRV)
       run: |
         metadata=$(cargo metadata --no-deps --format-version 1)
         msrv=$(echo $metadata | jq -r '.packages | map(select(.name == "lighthouse")) | .[0].rust_version')
-        echo "::set-output name=MSRV::$msrv"
+        echo "MSRV=$msrv" >> $GITHUB_OUTPUT
       id: extract_msrv
     outputs:
       MSRV: ${{ steps.extract_msrv.outputs.MSRV }}
@@ -37,7 +37,7 @@ jobs:
     name: cargo-fmt
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v3
     - name: Get latest version of stable Rust
       run: rustup update stable
     - name: Check formatting with cargo fmt
@@ -47,11 +47,13 @@ jobs:
     runs-on: ubuntu-latest
     needs: cargo-fmt
     steps:
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v3
     - name: Get latest version of stable Rust
       run: rustup update stable
     - name: Install Protoc
       uses: arduino/setup-protoc@v1
+      with:
+        repo-token: ${{ secrets.GITHUB_TOKEN }}
     - name: Install ganache
       run: sudo npm install -g ganache
     - name: Run tests in release
@@ -61,7 +63,7 @@ jobs:
     runs-on: windows-2019
     needs: cargo-fmt
     steps:
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v3
     - name: Get latest version of stable Rust
       run: rustup update stable
     - name: Use Node.js
@@ -89,11 +91,13 @@ jobs:
     runs-on: ubuntu-latest
     needs: cargo-fmt
     steps:
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v3
     - name: Get latest version of stable Rust
       run: rustup update stable
     - name: Install Protoc
       uses: arduino/setup-protoc@v1
+      with:
+        repo-token: ${{ secrets.GITHUB_TOKEN }}
     - name: Run beacon_chain tests for all known forks
       run: make test-beacon-chain
   op-pool-tests:
@@ -101,11 +105,13 @@ jobs:
     runs-on: ubuntu-latest
     needs: cargo-fmt
     steps:
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v3
     - name: Get latest version of stable Rust
       run: rustup update stable
     - name: Install Protoc
       uses: arduino/setup-protoc@v1
+      with:
+        repo-token: ${{ secrets.GITHUB_TOKEN }}
     - name: Run operation_pool tests for all known forks
       run: make test-op-pool
   slasher-tests:
@@ -113,7 +119,7 @@ jobs:
     runs-on: ubuntu-latest
     needs: cargo-fmt
     steps:
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v3
     - name: Get latest version of stable Rust
       run: rustup update stable
     - name: Run slasher tests for all supported backends
@@ -123,11 +129,13 @@ jobs:
     runs-on: ubuntu-22.04
     needs: cargo-fmt
     steps:
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v3
     - name: Get latest version of stable Rust
       run: rustup update stable
     - name: Install Protoc
       uses: arduino/setup-protoc@v1
+      with:
+        repo-token: ${{ secrets.GITHUB_TOKEN }}
     - name: Install ganache
       run: sudo npm install -g ganache
     - name: Run tests in debug
@@ -137,11 +145,13 @@ jobs:
     runs-on: ubuntu-latest
     needs: cargo-fmt
     steps:
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v3
     - name: Get latest version of stable Rust
       run: rustup update stable
     - name: Install Protoc
       uses: arduino/setup-protoc@v1
+      with:
+        repo-token: ${{ secrets.GITHUB_TOKEN }}
     - name: Run state_transition_vectors in release.
       run: make run-state-transition-tests
   ef-tests-ubuntu:
@@ -149,11 +159,13 @@ jobs:
     runs-on: ubuntu-latest
     needs: cargo-fmt
     steps:
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v3
     - name: Get latest version of stable Rust
       run: rustup update stable
     - name: Install Protoc
       uses: arduino/setup-protoc@v1
+      with:
+        repo-token: ${{ secrets.GITHUB_TOKEN }}
     - name: Run consensus-spec-tests with blst, milagro and fake_crypto
       run: make test-ef
   dockerfile-ubuntu:
@@ -161,7 +173,7 @@ jobs:
     runs-on: ubuntu-latest
     needs: cargo-fmt
     steps:
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v3
     - name: Get latest version of stable Rust
       run: rustup update stable
     - name: Build the root Dockerfile
@@ -173,11 +185,13 @@ jobs:
     runs-on: ubuntu-latest
     needs: cargo-fmt
     steps:
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v3
     - name: Get latest version of stable Rust
       run: rustup update stable
     - name: Install Protoc
       uses: arduino/setup-protoc@v1
+      with:
+        repo-token: ${{ secrets.GITHUB_TOKEN }}
     - name: Install ganache
       run: sudo npm install -g ganache
     - name: Run the beacon chain sim that starts from an eth1 contract
@@ -187,11 +201,13 @@ jobs:
     runs-on: ubuntu-latest
     needs: cargo-fmt
     steps:
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v3
     - name: Get latest version of stable Rust
       run: rustup update stable
     - name: Install Protoc
       uses: arduino/setup-protoc@v1
+      with:
+        repo-token: ${{ secrets.GITHUB_TOKEN }}
     - name: Install ganache
       run: sudo npm install -g ganache
     - name: Run the beacon chain sim and go through the merge transition
@@ -201,11 +217,13 @@ jobs:
     runs-on: ubuntu-latest
     needs: cargo-fmt
     steps:
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v3
     - name: Get latest version of stable Rust
       run: rustup update stable
     - name: Install Protoc
       uses: arduino/setup-protoc@v1
+      with:
+        repo-token: ${{ secrets.GITHUB_TOKEN }}
     - name: Install ganache
       run: sudo npm install -g ganache
     - name: Run the beacon chain sim without an eth1 connection
@@ -215,11 +233,13 @@ jobs:
     runs-on: ubuntu-latest
     needs: cargo-fmt
     steps:
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v3
     - name: Get latest version of stable Rust
       run: rustup update stable
     - name: Install Protoc
       uses: arduino/setup-protoc@v1
+      with:
+        repo-token: ${{ secrets.GITHUB_TOKEN }}
     - name: Install ganache
       run: sudo npm install -g ganache
     - name: Run the syncing simulator
@@ -229,11 +249,13 @@ jobs:
     runs-on: ubuntu-latest
     needs: cargo-fmt
     steps:
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v3
     - name: Get latest version of stable Rust
       run: rustup update stable
     - name: Install Protoc
       uses: arduino/setup-protoc@v1
+      with:
+        repo-token: ${{ secrets.GITHUB_TOKEN }}
     - name: Install ganache
       run: sudo npm install -g ganache
     - name: Install lighthouse and lcli
@@ -253,17 +275,19 @@ jobs:
     runs-on: ubuntu-latest
     needs: cargo-fmt
     steps:
-    - uses: actions/checkout@v1
-    - uses: actions/setup-go@v2
+    - uses: actions/checkout@v3
+    - uses: actions/setup-go@v3
       with:
         go-version: '1.17'
-    - uses: actions/setup-dotnet@v1
+    - uses: actions/setup-dotnet@v3
       with:
         dotnet-version: '6.0.201'
     - name: Get latest version of stable Rust
       run: rustup update stable
     - name: Install Protoc
       uses: arduino/setup-protoc@v1
+      with:
+        repo-token: ${{ secrets.GITHUB_TOKEN }}
     - name: Run exec engine integration tests in release
       run: make test-exec-engine
   check-benchmarks:
@@ -271,11 +295,13 @@ jobs:
     runs-on: ubuntu-latest
     needs: cargo-fmt
     steps:
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v3
     - name: Get latest version of stable Rust
       run: rustup update stable
     - name: Install Protoc
       uses: arduino/setup-protoc@v1
+      with:
+        repo-token: ${{ secrets.GITHUB_TOKEN }}
     - name: Typecheck benchmark code without running it
       run: make check-benches
   check-consensus:
@@ -283,7 +309,7 @@ jobs:
     runs-on: ubuntu-latest
     needs: cargo-fmt
     steps:
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v3
     - name: Get latest version of stable Rust
       run: rustup update stable
     - name: Typecheck consensus code in strict mode
@@ -293,11 +319,13 @@ jobs:
     runs-on: ubuntu-latest
     needs: cargo-fmt
     steps:
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v3
     - name: Get latest version of stable Rust
       run: rustup update stable
     - name: Install Protoc
       uses: arduino/setup-protoc@v1
+      with:
+        repo-token: ${{ secrets.GITHUB_TOKEN }}
     - name: Lint code for quality and style with Clippy
       run: make lint
     - name: Certify Cargo.lock freshness
@@ -308,7 +336,7 @@ jobs:
     needs: cargo-fmt
     continue-on-error: true
     steps:
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v3
     - name: Install SigP Clippy fork
       run: |
         cd ..
@@ -319,6 +347,8 @@ jobs:
         cargo build --release --bin cargo-clippy --bin clippy-driver -Zunstable-options --out-dir $(rustc --print=sysroot)/bin
     - name: Install Protoc
       uses: arduino/setup-protoc@v1
+      with:
+        repo-token: ${{ secrets.GITHUB_TOKEN }}
     - name: Run Clippy with the disallowed-from-async lint
       run: make nightly-lint
   check-msrv:
@@ -326,11 +356,13 @@ jobs:
     runs-on: ubuntu-latest
     needs: [cargo-fmt, extract-msrv]
     steps:
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v3
     - name: Install Rust @ MSRV (${{ needs.extract-msrv.outputs.MSRV }})
       run: rustup override set ${{ needs.extract-msrv.outputs.MSRV }}
     - name: Install Protoc
       uses: arduino/setup-protoc@v1
+      with:
+        repo-token: ${{ secrets.GITHUB_TOKEN }}
     - name: Run cargo check
       run: cargo check --workspace
   arbitrary-check:
@@ -338,7 +370,7 @@ jobs:
     runs-on: ubuntu-latest
     needs: cargo-fmt
     steps:
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v3
     - name: Get latest version of stable Rust
       run: rustup update stable
     - name: Validate state_processing feature arbitrary-fuzz
@@ -348,7 +380,7 @@ jobs:
     runs-on: ubuntu-latest
     needs: cargo-fmt
     steps:
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v3
     - name: Get latest version of stable Rust
       run: rustup update stable
     - name: Run cargo audit to identify known security vulnerabilities reported to the RustSec Advisory Database
@@ -358,7 +390,7 @@ jobs:
     runs-on: ubuntu-latest
     needs: cargo-fmt
     steps:
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v3
     - name: Run cargo vendor to make sure dependencies can be vendored for packaging, reproducibility and archival purpose
       run:  CARGO_HOME=$(readlink -f $HOME) make vendor
   cargo-udeps:
@@ -366,13 +398,15 @@ jobs:
     runs-on: ubuntu-latest
     needs: cargo-fmt
     steps:
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v3
     - name: Install Rust (${{ env.PINNED_NIGHTLY }})
       run: rustup toolchain install $PINNED_NIGHTLY
     # NOTE: cargo-udeps version is pinned until this issue is resolved:
     # https://github.com/est31/cargo-udeps/issues/135
     - name: Install Protoc
       uses: arduino/setup-protoc@v1
+      with:
+        repo-token: ${{ secrets.GITHUB_TOKEN }}
     - name: Install cargo-udeps
       run: cargo install cargo-udeps --locked --force --version 0.1.30
     - name: Create Cargo config dir
@@ -384,3 +418,14 @@ jobs:
     env:
       # Allow warnings on Nightly
       RUSTFLAGS: ""
+  compile-with-beta-compiler:
+    name: compile-with-beta-compiler
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v3
+    - name: Install dependencies
+      run: sudo apt install -y git gcc g++ make cmake pkg-config llvm-dev libclang-dev clang protobuf-compiler
+    - name: Use Rust beta
+      run: rustup override set beta
+    - name: Run make
+      run: make
diff --git a/Cargo.lock b/Cargo.lock
index e98bd7a01..2555fb91b 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -111,16 +111,16 @@ version = "0.7.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "fcb51a0695d8f838b1ee009b3fbf66bda078cd64590202a864a8f3e8c4315c47"
 dependencies = [
- "getrandom 0.2.7",
+ "getrandom 0.2.8",
  "once_cell",
  "version_check",
 ]
 
 [[package]]
 name = "aho-corasick"
-version = "0.7.18"
+version = "0.7.19"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1e37cfd5e7657ada45f742d6e99ca5788580b5c529dc78faf11ece6dc702656f"
+checksum = "b4f55bd91a0978cbfd91c457a164bab8b4001c833b7f323132c0a4e1922dd44e"
 dependencies = [
  "memchr",
 ]
@@ -130,6 +130,15 @@ name = "amcl"
 version = "0.3.0"
 source = "git+https://github.com/sigp/milagro_bls?tag=v1.4.2#16655aa033175a90c10ef02aa144e2835de23aec"
 
+[[package]]
+name = "android_system_properties"
+version = "0.1.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "819e7219dbd41043ac279b19830f2efc897156490d7fd6ea916720117ee66311"
+dependencies = [
+ "libc",
+]
+
 [[package]]
 name = "ansi_term"
 version = "0.12.1"
@@ -141,24 +150,24 @@ dependencies = [
 
 [[package]]
 name = "anyhow"
-version = "1.0.58"
+version = "1.0.66"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "bb07d2053ccdbe10e2af2995a2f116c1330396493dc1269f6a91d0ae82e19704"
+checksum = "216261ddc8289130e551ddcd5ce8a064710c0d064a4d2895c67151c92b5443f6"
 
 [[package]]
 name = "arbitrary"
-version = "1.1.3"
+version = "1.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5a7924531f38b1970ff630f03eb20a2fde69db5c590c93b0f3482e95dcc5fd60"
+checksum = "29d47fbf90d5149a107494b15a7dc8d69b351be2db3bb9691740e88ec17fd880"
 dependencies = [
  "derive_arbitrary",
 ]
 
 [[package]]
 name = "arc-swap"
-version = "1.5.0"
+version = "1.5.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c5d78ce20460b82d3fa150275ed9d55e21064fc7951177baacf86a145c4a4b1f"
+checksum = "983cd8b9d4b02a6dc6ffa557262eb5858a27a0038ffffe21a0f133eaa819a164"
 
 [[package]]
 name = "arrayref"
@@ -201,9 +210,9 @@ dependencies = [
 
 [[package]]
 name = "async-trait"
-version = "0.1.56"
+version = "0.1.58"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "96cf8829f67d2eab0b2dfa42c5d0ef737e0724e4a82b01b3e292456202b19716"
+checksum = "1e805d94e6b5001b651426cf4cd446b1ab5f319d27bab5c644f61de0a804360c"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -285,9 +294,9 @@ checksum = "d468802bab17cbc0cc575e9b053f41e72aa36bfa6b7f55e3529ffa43161b97fa"
 
 [[package]]
 name = "axum"
-version = "0.5.16"
+version = "0.5.17"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c9e3356844c4d6a6d6467b8da2cffb4a2820be256f50a3a386c9d152bab31043"
+checksum = "acee9fd5073ab6b045a275b3e709c163dd36c90685219cb21804a147b58dba43"
 dependencies = [
  "async-trait",
  "axum-core",
@@ -297,7 +306,7 @@ dependencies = [
  "http",
  "http-body",
  "hyper",
- "itoa 1.0.2",
+ "itoa 1.0.4",
  "matchit",
  "memchr",
  "mime",
@@ -316,9 +325,9 @@ dependencies = [
 
 [[package]]
 name = "axum-core"
-version = "0.2.8"
+version = "0.2.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d9f0c0a60006f2a293d82d571f635042a72edf927539b7685bd62d361963839b"
+checksum = "37e5939e02c56fecd5c017c37df4238c0a839fa76b7f97acdd7efb804fd181cc"
 dependencies = [
  "async-trait",
  "bytes",
@@ -353,15 +362,15 @@ checksum = "349a06037c7bf932dd7e7d1f653678b2038b9ad46a74102f1fc7bd7872678cce"
 
 [[package]]
 name = "base64"
-version = "0.13.0"
+version = "0.13.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "904dfeac50f3cdaba28fc6f57fdcddb75f49ed61346676a78c4ffe55877802fd"
+checksum = "9e1b586273c5702936fe7b7d6896644d8be71e6314cfe09d3167c95f712589e8"
 
 [[package]]
 name = "base64ct"
-version = "1.5.1"
+version = "1.5.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3bdca834647821e0b13d9539a8634eb62d3501b6b6c2cec1722786ee6671b851"
+checksum = "b645a089122eccb6111b4f81cbc1a49f5900ac4666bb93ac027feaecf15607bf"
 
 [[package]]
 name = "beacon-api-client"
@@ -440,7 +449,7 @@ dependencies = [
 
 [[package]]
 name = "beacon_node"
-version = "3.2.1"
+version = "3.3.0"
 dependencies = [
  "beacon_chain",
  "clap",
@@ -536,7 +545,7 @@ version = "0.10.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b9cf849ee05b2ee5fba5e36f97ff8ec2533916700fc0758d40d92136a42f3388"
 dependencies = [
- "digest 0.10.3",
+ "digest 0.10.5",
 ]
 
 [[package]]
@@ -551,9 +560,9 @@ dependencies = [
 
 [[package]]
 name = "block-buffer"
-version = "0.10.2"
+version = "0.10.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0bf7fe51849ea569fd452f37822f606a5cabb684dc918707a0193fd4664ff324"
+checksum = "69cce20737498f97b993470a6e536b8523f0af7892a4f928cceb1ac5e52ebe7e"
 dependencies = [
  "generic-array",
 ]
@@ -598,7 +607,7 @@ dependencies = [
 
 [[package]]
 name = "boot_node"
-version = "3.2.1"
+version = "3.3.0"
 dependencies = [
  "beacon_node",
  "clap",
@@ -663,15 +672,15 @@ dependencies = [
 
 [[package]]
 name = "bumpalo"
-version = "3.10.0"
+version = "3.11.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "37ccbd214614c6783386c1af30caf03192f17891059cecc394b4fb119e363de3"
+checksum = "572f695136211188308f16ad2ca5c851a712c464060ae6974944458eb83880ba"
 
 [[package]]
 name = "byte-slice-cast"
-version = "1.2.1"
+version = "1.2.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "87c5fdd0166095e1d463fc6cc01aa8ce547ad77a4e84d42eb6762b084e28067e"
+checksum = "c3ac9f8b63eca6fd385229b3675f6cc0dc5c8a5c8a54a59d4f52ffd670d87b0c"
 
 [[package]]
 name = "byteorder"
@@ -681,9 +690,9 @@ checksum = "14c189c53d098945499cdfa7ecc63567cf3886b3332b312a5b4585d8d3a6a610"
 
 [[package]]
 name = "bytes"
-version = "1.2.0"
+version = "1.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f0b3de4a0c5e67e16066a0715723abd91edc2f9001d09c46e1dca929351e130e"
+checksum = "ec8a7b6a70fde80372154c65702f00a0f56f3e1c36abbc6c440484be248856db"
 dependencies = [
  "serde",
 ]
@@ -741,9 +750,9 @@ checksum = "37b2a672a2cb129a2e41c10b1224bb368f9f37a2b16b612598138befd7b37eb5"
 
 [[package]]
 name = "cc"
-version = "1.0.73"
+version = "1.0.74"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2fff2a6927b3bb87f9595d67196a70493f627687a71d87a0d692242c33f58c11"
+checksum = "581f5dba903aac52ea3feb5ec4810848460ee833876f1f9b0fdeab1f19091574"
 
 [[package]]
 name = "cexpr"
@@ -787,14 +796,16 @@ dependencies = [
 
 [[package]]
 name = "chrono"
-version = "0.4.19"
+version = "0.4.22"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "670ad68c9088c2a963aaa298cb369688cf3f9465ce5e2d4ca10e6e0098a1ce73"
+checksum = "bfd4d1b31faaa3a89d7934dbded3111da0d2ef28e3ebccdb4f0179f5929d1ef1"
 dependencies = [
- "libc",
+ "iana-time-zone",
+ "js-sys",
  "num-integer",
  "num-traits",
  "time 0.1.44",
+ "wasm-bindgen",
  "winapi",
 ]
 
@@ -809,9 +820,9 @@ dependencies = [
 
 [[package]]
 name = "clang-sys"
-version = "1.3.3"
+version = "1.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5a050e2153c5be08febd6734e29298e844fdb0fa21aeddd63b4eb7baa106c69b"
+checksum = "fa2e27ae6ab525c3d369ded447057bca5438d86dc3a68f6faafb8269ba82ebf3"
 dependencies = [
  "glob",
  "libc",
@@ -881,7 +892,7 @@ dependencies = [
  "slot_clock",
  "store",
  "task_executor",
- "time 0.3.11",
+ "time 0.3.16",
  "timer",
  "tokio",
  "types",
@@ -889,13 +900,23 @@ dependencies = [
 
 [[package]]
 name = "cmake"
-version = "0.1.48"
+version = "0.1.49"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e8ad8cef104ac57b68b89df3208164d228503abbdce70f6880ffa3d970e7443a"
+checksum = "db34956e100b30725f2eb215f90d4871051239535632f84fea3bc92722c66b7c"
 dependencies = [
  "cc",
 ]
 
+[[package]]
+name = "codespan-reporting"
+version = "0.11.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3538270d33cc669650c4b093848450d380def10c331d38c768e34cac80576e6e"
+dependencies = [
+ "termcolor",
+ "unicode-width",
+]
+
 [[package]]
 name = "compare_fields"
 version = "0.2.0"
@@ -1035,26 +1056,24 @@ dependencies = [
 
 [[package]]
 name = "crossbeam-epoch"
-version = "0.9.10"
+version = "0.9.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "045ebe27666471bb549370b4b0b3e51b07f56325befa4284db65fc89c02511b1"
+checksum = "f916dfc5d356b0ed9dae65f1db9fc9770aa2851d2662b988ccf4fe3516e86348"
 dependencies = [
  "autocfg 1.1.0",
  "cfg-if",
  "crossbeam-utils",
  "memoffset",
- "once_cell",
  "scopeguard",
 ]
 
 [[package]]
 name = "crossbeam-utils"
-version = "0.8.11"
+version = "0.8.12"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "51887d4adc7b564537b15adcfb307936f8075dfcd5f00dde9a9f1d29383682bc"
+checksum = "edbafec5fa1f196ca66527c1b12c2ec4745ca14b50f1ad8f9f6f720b55d11fac"
 dependencies = [
  "cfg-if",
- "once_cell",
 ]
 
 [[package]]
@@ -1065,12 +1084,12 @@ checksum = "7a81dae078cea95a014a339291cec439d2f232ebe854a9d672b796c6afafa9b7"
 
 [[package]]
 name = "crypto-bigint"
-version = "0.4.8"
+version = "0.4.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9f2b443d17d49dad5ef0ede301c3179cc923b8822f3393b4d2c28c269dd4a122"
+checksum = "ef2b4b23cddf68b89b8f8069890e8c270d54e2d5fe1b143820234805e4cb17ef"
 dependencies = [
  "generic-array",
- "rand_core 0.6.3",
+ "rand_core 0.6.4",
  "subtle",
  "zeroize",
 ]
@@ -1138,11 +1157,11 @@ dependencies = [
 
 [[package]]
 name = "ctrlc"
-version = "3.2.2"
+version = "3.2.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b37feaa84e6861e00a1f5e5aa8da3ee56d605c9992d33e082786754828e20865"
+checksum = "1d91974fbbe88ec1df0c24a4f00f99583667a7e2e6272b2b92d294d81e462173"
 dependencies = [
- "nix 0.24.2",
+ "nix 0.25.0",
  "winapi",
 ]
 
@@ -1167,11 +1186,55 @@ checksum = "4033478fbf70d6acf2655ac70da91ee65852d69daf7a67bf7a2f518fb47aafcf"
 dependencies = [
  "byteorder",
  "digest 0.9.0",
- "rand_core 0.6.3",
+ "rand_core 0.6.4",
  "subtle",
  "zeroize",
 ]
 
+[[package]]
+name = "cxx"
+version = "1.0.80"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6b7d4e43b25d3c994662706a1d4fcfc32aaa6afd287502c111b237093bb23f3a"
+dependencies = [
+ "cc",
+ "cxxbridge-flags",
+ "cxxbridge-macro",
+ "link-cplusplus",
+]
+
+[[package]]
+name = "cxx-build"
+version = "1.0.80"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "84f8829ddc213e2c1368e51a2564c552b65a8cb6a28f31e576270ac81d5e5827"
+dependencies = [
+ "cc",
+ "codespan-reporting",
+ "once_cell",
+ "proc-macro2",
+ "quote",
+ "scratch",
+ "syn",
+]
+
+[[package]]
+name = "cxxbridge-flags"
+version = "1.0.80"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e72537424b474af1460806647c41d4b6d35d09ef7fe031c5c2fa5766047cc56a"
+
+[[package]]
+name = "cxxbridge-macro"
+version = "1.0.80"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "309e4fb93eed90e1e14bea0da16b209f81813ba9fc7830c20ed151dd7bc0a4d7"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "darling"
 version = "0.13.4"
@@ -1259,9 +1322,9 @@ checksum = "b72465f46d518f6015d9cf07f7f3013a95dd6b9c2747c3d65ae0cce43929d14f"
 
 [[package]]
 name = "delay_map"
-version = "0.1.1"
+version = "0.1.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6716ce9729be9628979ae1ff63e8bc8b7ad53b5472a2633bf079607a55328d36"
+checksum = "9c4d75d3abfe4830dcbf9bcb1b926954e121669f74dd1ca7aa0183b1755d83f6"
 dependencies = [
  "futures",
  "tokio-util 0.6.10",
@@ -1276,7 +1339,7 @@ dependencies = [
  "hex",
  "reqwest",
  "serde_json",
- "sha2 0.10.2",
+ "sha2 0.10.6",
  "tree_hash",
  "types",
 ]
@@ -1304,9 +1367,9 @@ dependencies = [
 
 [[package]]
 name = "derive_arbitrary"
-version = "1.1.3"
+version = "1.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c9a577516173adb681466d517d39bd468293bc2c2a16439375ef0f35bba45f3d"
+checksum = "4903dff04948f22033ca30232ab8eca2c3fc4c913a8b6a34ee5199699814817f"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -1337,11 +1400,11 @@ dependencies = [
 
 [[package]]
 name = "digest"
-version = "0.10.3"
+version = "0.10.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f2fb860ca6fafa5552fb6d0e816a69c8e49f0908bf524e30a90d97c85892d506"
+checksum = "adfbc57365a37acbd2ebf2b64d7e69bb766e2fea813521ed536f5d0520dcf86c"
 dependencies = [
- "block-buffer 0.10.2",
+ "block-buffer 0.10.3",
  "crypto-common",
  "subtle",
 ]
@@ -1432,9 +1495,9 @@ dependencies = [
 
 [[package]]
 name = "dtoa"
-version = "1.0.2"
+version = "1.0.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5caaa75cbd2b960ff1e5392d2cfb1f44717fffe12fc1f32b7b5d1267f99732a6"
+checksum = "f8a6eee2d5d0d113f015688310da018bd1d864d86bd567c8fca9c266889e1bfa"
 
 [[package]]
 name = "ecdsa"
@@ -1504,9 +1567,9 @@ dependencies = [
 
 [[package]]
 name = "either"
-version = "1.7.0"
+version = "1.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3f107b87b6afc2a64fd13cac55fe06d6c8859f12d4b14cbcdd2c67d0976781be"
+checksum = "90e5c1c8368803113bf0c9584fc495a58b86dc8a29edbf8fe877d21d9507e797"
 
 [[package]]
 name = "elliptic-curve"
@@ -1517,12 +1580,12 @@ dependencies = [
  "base16ct",
  "crypto-bigint",
  "der",
- "digest 0.10.3",
+ "digest 0.10.5",
  "ff",
  "generic-array",
  "group",
  "pkcs8",
- "rand_core 0.6.3",
+ "rand_core 0.6.4",
  "sec1",
  "subtle",
  "zeroize",
@@ -1553,7 +1616,7 @@ dependencies = [
  "rand 0.8.5",
  "rlp",
  "serde",
- "sha3 0.10.1",
+ "sha3 0.10.6",
  "zeroize",
 ]
 
@@ -1581,9 +1644,9 @@ dependencies = [
 
 [[package]]
 name = "env_logger"
-version = "0.9.0"
+version = "0.9.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0b2cf0344971ee6c64c31be0d530793fba457d322dfec2810c453d0ef228f9c3"
+checksum = "c90bf5f19754d10198ccb95b70664fc925bd1fc090a0fd9a6ebc54acc8cd6272"
 dependencies = [
  "atty",
  "humantime",
@@ -1712,7 +1775,7 @@ dependencies = [
  "lazy_static",
  "ring",
  "rustc-hex",
- "sha2 0.10.2",
+ "sha2 0.10.6",
  "wasm-bindgen-test",
 ]
 
@@ -1739,7 +1802,7 @@ dependencies = [
  "hex",
  "num-bigint-dig",
  "ring",
- "sha2 0.10.2",
+ "sha2 0.10.6",
  "zeroize",
 ]
 
@@ -1869,9 +1932,9 @@ dependencies = [
 
 [[package]]
 name = "ethabi"
-version = "17.1.0"
+version = "17.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f186de076b3e77b8e6d73c99d1b52edc2a229e604f4b5eb6992c06c11d79d537"
+checksum = "e4966fba78396ff92db3b817ee71143eccd98acf0f876b8d600e585a670c5d1b"
 dependencies = [
  "ethereum-types 0.13.1",
  "hex",
@@ -1879,7 +1942,7 @@ dependencies = [
  "regex",
  "serde",
  "serde_json",
- "sha3 0.10.1",
+ "sha3 0.10.6",
  "thiserror",
  "uint",
 ]
@@ -1970,7 +2033,7 @@ dependencies = [
  "bytes",
  "chrono",
  "elliptic-curve",
- "ethabi 17.1.0",
+ "ethabi 17.2.0",
  "fastrlp",
  "generic-array",
  "hex",
@@ -2001,7 +2064,7 @@ dependencies = [
  "futures-core",
  "futures-timer",
  "futures-util",
- "getrandom 0.2.7",
+ "getrandom 0.2.8",
  "hashers",
  "hex",
  "http",
@@ -2138,9 +2201,9 @@ dependencies = [
 
 [[package]]
 name = "fastrlp-derive"
-version = "0.1.2"
+version = "0.1.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e1fa41ebc231af281098b11ad4a4f6182ec9096902afffe948034a20d4e1385a"
+checksum = "d9e9158c1d8f0a7a716c9191562eaabba70268ba64972ef4871ce8d66fd08872"
 dependencies = [
  "bytes",
  "proc-macro2",
@@ -2150,11 +2213,11 @@ dependencies = [
 
 [[package]]
 name = "ff"
-version = "0.12.0"
+version = "0.12.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "df689201f395c6b90dfe87127685f8dbfc083a5e779e613575d8bd7314300c3e"
+checksum = "d013fc25338cc558c5c2cfbad646908fb23591e2404481826742b651c9af7160"
 dependencies = [
- "rand_core 0.6.3",
+ "rand_core 0.6.4",
  "subtle",
 ]
 
@@ -2249,11 +2312,10 @@ dependencies = [
 
 [[package]]
 name = "form_urlencoded"
-version = "1.0.1"
+version = "1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5fc25a87fa4fd2094bffb06925852034d90a17f0d1e05197d4956d3555752191"
+checksum = "a9c384f161156f5260c24a097c56119f9be8c798586aecc13afbcbe7b7e26bf8"
 dependencies = [
- "matches",
  "percent-encoding",
 ]
 
@@ -2281,9 +2343,9 @@ checksum = "e6d5a32815ae3f33302d95fdcb2ce17862f8c65363dcfd29360480ba1001fc9c"
 
 [[package]]
 name = "futures"
-version = "0.3.21"
+version = "0.3.25"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f73fe65f54d1e12b726f517d3e2135ca3125a437b6d998caf1962961f7172d9e"
+checksum = "38390104763dc37a5145a53c29c63c1290b5d316d6086ec32c293f6736051bb0"
 dependencies = [
  "futures-channel",
  "futures-core",
@@ -2296,9 +2358,9 @@ dependencies = [
 
 [[package]]
 name = "futures-channel"
-version = "0.3.21"
+version = "0.3.25"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c3083ce4b914124575708913bca19bfe887522d6e2e6d0952943f5eac4a74010"
+checksum = "52ba265a92256105f45b719605a571ffe2d1f0fea3807304b522c1d778f79eed"
 dependencies = [
  "futures-core",
  "futures-sink",
@@ -2306,15 +2368,15 @@ dependencies = [
 
 [[package]]
 name = "futures-core"
-version = "0.3.21"
+version = "0.3.25"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0c09fd04b7e4073ac7156a9539b57a484a8ea920f79c7c675d05d289ab6110d3"
+checksum = "04909a7a7e4633ae6c4a9ab280aeb86da1236243a77b694a49eacd659a4bd3ac"
 
 [[package]]
 name = "futures-executor"
-version = "0.3.21"
+version = "0.3.25"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9420b90cfa29e327d0429f19be13e7ddb68fa1cccb09d65e5706b8c7a749b8a6"
+checksum = "7acc85df6714c176ab5edf386123fafe217be88c0840ec11f199441134a074e2"
 dependencies = [
  "futures-core",
  "futures-task",
@@ -2324,15 +2386,15 @@ dependencies = [
 
 [[package]]
 name = "futures-io"
-version = "0.3.21"
+version = "0.3.25"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "fc4045962a5a5e935ee2fdedaa4e08284547402885ab326734432bed5d12966b"
+checksum = "00f5fb52a06bdcadeb54e8d3671f8888a39697dcb0b81b23b55174030427f4eb"
 
 [[package]]
 name = "futures-macro"
-version = "0.3.21"
+version = "0.3.25"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "33c1e13800337f4d4d7a316bf45a567dbcb6ffe087f16424852d97e97a91f512"
+checksum = "bdfb8ce053d86b91919aad980c220b1fb8401a9394410e1c289ed7e66b61835d"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -2341,26 +2403,26 @@ dependencies = [
 
 [[package]]
 name = "futures-rustls"
-version = "0.22.1"
+version = "0.22.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e01fe9932a224b72b45336d96040aa86386d674a31d0af27d800ea7bc8ca97fe"
+checksum = "d2411eed028cdf8c8034eaf21f9915f956b6c3abec4d4c7949ee67f0721127bd"
 dependencies = [
  "futures-io",
- "rustls 0.20.6",
+ "rustls 0.20.7",
  "webpki 0.22.0",
 ]
 
 [[package]]
 name = "futures-sink"
-version = "0.3.21"
+version = "0.3.25"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "21163e139fa306126e6eedaf49ecdb4588f939600f0b1e770f4205ee4b7fa868"
+checksum = "39c15cf1a4aa79df40f1bb462fb39676d0ad9e366c2a33b590d7c66f4f81fcf9"
 
 [[package]]
 name = "futures-task"
-version = "0.3.21"
+version = "0.3.25"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "57c66a976bf5909d801bbef33416c41372779507e7a6b3a5e25e4749c58f776a"
+checksum = "2ffb393ac5d9a6eaa9d3fdf37ae2776656b706e200c8e16b1bdb227f5198e6ea"
 
 [[package]]
 name = "futures-timer"
@@ -2370,9 +2432,9 @@ checksum = "e64b03909df88034c26dc1547e8970b91f98bdb65165d6a4e9110d94263dbb2c"
 
 [[package]]
 name = "futures-util"
-version = "0.3.21"
+version = "0.3.25"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d8b7abd5d659d9b90c8cba917f6ec750a74e2dc23902ef9cd4cc8c8b22e6036a"
+checksum = "197676987abd2f9cadff84926f410af1c183608d36641465df73ae8211dc65d6"
 dependencies = [
  "futures-channel",
  "futures-core",
@@ -2397,9 +2459,9 @@ dependencies = [
 
 [[package]]
 name = "generic-array"
-version = "0.14.5"
+version = "0.14.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "fd48d33ec7f05fbfa152300fdad764757cbded343c1aa1cff2fbaf4134851803"
+checksum = "bff49e947297f3312447abdca79f45f4738097cc82b06e72054d2223f601f1b9"
 dependencies = [
  "typenum",
  "version_check",
@@ -2441,9 +2503,9 @@ dependencies = [
 
 [[package]]
 name = "getrandom"
-version = "0.2.7"
+version = "0.2.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4eb1a864a501629691edf6c15a593b7a51eebaa1e8468e9ddc623de7c9b58ec6"
+checksum = "c05aeb6a22b8f62540c194aac980f2115af067bfe15a0734d7277a768d396b31"
 dependencies = [
  "cfg-if",
  "js-sys",
@@ -2498,20 +2560,20 @@ checksum = "9b919933a397b79c37e33b77bb2aa3dc8eb6e165ad809e58ff75bc7db2e34574"
 
 [[package]]
 name = "group"
-version = "0.12.0"
+version = "0.12.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7391856def869c1c81063a03457c676fbcd419709c3dfb33d8d319de484b154d"
+checksum = "5dfbfb3a6cfbd390d5c9564ab283a0349b9b9fcd46a706c1eb10e0db70bfbac7"
 dependencies = [
  "ff",
- "rand_core 0.6.3",
+ "rand_core 0.6.4",
  "subtle",
 ]
 
 [[package]]
 name = "h2"
-version = "0.3.13"
+version = "0.3.15"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "37a82c6d637fc9515a4694bbf1cb2457b79d81ce52b3108bdeea58b07dd34a57"
+checksum = "5f9f29bc9dda355256b2916cf526ab02ce0aeaaaf2bad60d65ef3f12f11dd0f4"
 dependencies = [
  "bytes",
  "fnv",
@@ -2522,7 +2584,7 @@ dependencies = [
  "indexmap",
  "slab",
  "tokio",
- "tokio-util 0.7.3",
+ "tokio-util 0.7.4",
  "tracing",
 ]
 
@@ -2570,9 +2632,9 @@ dependencies = [
 
 [[package]]
 name = "headers"
-version = "0.3.7"
+version = "0.3.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4cff78e5788be1e0ab65b04d306b2ed5092c815ec97ec70f4ebd5aee158aa55d"
+checksum = "f3e372db8e5c0d213e0cd0b9be18be2aca3d44cf2fe30a9d46a65581cd454584"
 dependencies = [
  "base64",
  "bitflags",
@@ -2581,7 +2643,7 @@ dependencies = [
  "http",
  "httpdate",
  "mime",
- "sha-1 0.10.0",
+ "sha1",
 ]
 
 [[package]]
@@ -2655,7 +2717,7 @@ version = "0.12.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6c49c37c09c17a53d937dfbb742eb3a961d65a994e6bcdcf37e7399d0cc8ab5e"
 dependencies = [
- "digest 0.10.3",
+ "digest 0.10.5",
 ]
 
 [[package]]
@@ -2688,7 +2750,7 @@ checksum = "75f43d41e26995c17e71ee126451dd3941010b0514a81a9d11f3b341debc2399"
 dependencies = [
  "bytes",
  "fnv",
- "itoa 1.0.2",
+ "itoa 1.0.4",
 ]
 
 [[package]]
@@ -2714,6 +2776,7 @@ version = "0.1.0"
 dependencies = [
  "beacon_chain",
  "bs58",
+ "directory",
  "environment",
  "eth1",
  "eth2",
@@ -2738,6 +2801,8 @@ dependencies = [
  "slot_clock",
  "state_processing",
  "store",
+ "sysinfo",
+ "system_health",
  "task_executor",
  "tokio",
  "tokio-stream",
@@ -2771,9 +2836,9 @@ dependencies = [
 
 [[package]]
 name = "httparse"
-version = "1.7.1"
+version = "1.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "496ce29bb5a52785b44e0f7ca2847ae0bb839c9bd28f69acac9b99d461c0c04c"
+checksum = "d897f394bad6a705d5f4104762e116a75639e470d80901eed05a860a95cb1904"
 
 [[package]]
 name = "httpdate"
@@ -2789,9 +2854,9 @@ checksum = "9a3a5bfb195931eeb336b2a7b4d761daec841b97f947d34394601737a7bba5e4"
 
 [[package]]
 name = "hyper"
-version = "0.14.20"
+version = "0.14.22"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "02c929dc5c39e335a03c405292728118860721b10190d98c2a0f0efd5baafbac"
+checksum = "abfba89e19b959ca163c7752ba59d737c1ceea53a5d31a149c805446fc958064"
 dependencies = [
  "bytes",
  "futures-channel",
@@ -2802,7 +2867,7 @@ dependencies = [
  "http-body",
  "httparse",
  "httpdate",
- "itoa 1.0.2",
+ "itoa 1.0.4",
  "pin-project-lite 0.2.9",
  "socket2",
  "tokio",
@@ -2819,7 +2884,7 @@ checksum = "d87c48c02e0dc5e3b849a2041db3029fd066650f8f717c07bf8ed78ccb895cac"
 dependencies = [
  "http",
  "hyper",
- "rustls 0.20.6",
+ "rustls 0.20.7",
  "tokio",
  "tokio-rustls 0.23.4",
 ]
@@ -2837,6 +2902,30 @@ dependencies = [
  "tokio-native-tls",
 ]
 
+[[package]]
+name = "iana-time-zone"
+version = "0.1.53"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "64c122667b287044802d6ce17ee2ddf13207ed924c712de9a66a5814d5b64765"
+dependencies = [
+ "android_system_properties",
+ "core-foundation-sys",
+ "iana-time-zone-haiku",
+ "js-sys",
+ "wasm-bindgen",
+ "winapi",
+]
+
+[[package]]
+name = "iana-time-zone-haiku"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0703ae284fc167426161c2e3f1da3ea71d94b21bedbcc9494e92b28e334e3dca"
+dependencies = [
+ "cxx",
+ "cxx-build",
+]
+
 [[package]]
 name = "ident_case"
 version = "1.0.1"
@@ -2854,6 +2943,16 @@ dependencies = [
  "unicode-normalization",
 ]
 
+[[package]]
+name = "idna"
+version = "0.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e14ddfc70884202db2244c223200c204c2bda1bc6e0998d11b5e024d657209e6"
+dependencies = [
+ "unicode-bidi",
+ "unicode-normalization",
+]
+
 [[package]]
 name = "if-addrs"
 version = "0.6.7"
@@ -2913,7 +3012,7 @@ version = "0.6.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ba6a270039626615617f3f36d15fc827041df3b78c439da2cadfa47455a77f2f"
 dependencies = [
- "parity-scale-codec 3.1.5",
+ "parity-scale-codec 3.2.1",
 ]
 
 [[package]]
@@ -3005,9 +3104,9 @@ checksum = "879d54834c8c76457ef4293a689b2a8c59b076067ad77b15efafbb05f92a592b"
 
 [[package]]
 name = "itertools"
-version = "0.10.3"
+version = "0.10.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a9a9d19fa1e79b6215ff29b9d6880b706147f16e9b1dbb1e4e5947b5b02bc5e3"
+checksum = "b0fd2260e829bddf4cb6ea802289de2f86d6a7a690192fbe91b3f46e0f2c8473"
 dependencies = [
  "either",
 ]
@@ -3020,15 +3119,15 @@ checksum = "b71991ff56294aa922b450139ee08b3bfc70982c6b2c7562771375cf73542dd4"
 
 [[package]]
 name = "itoa"
-version = "1.0.2"
+version = "1.0.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "112c678d4050afce233f4f2852bb2eb519230b3cf12f33585275537d7e41578d"
+checksum = "4217ad341ebadf8d8e724e264f13e593e0648f5b3e94b3896a5df283be015ecc"
 
 [[package]]
 name = "js-sys"
-version = "0.3.59"
+version = "0.3.60"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "258451ab10b34f8af53416d1fdab72c22e805f0c92a1136d59470ec0b11138b2"
+checksum = "49409df3e3bf0856b916e2ceaca09ee28e6871cf7d9ce97a692cacfdb2a25a47"
 dependencies = [
  "wasm-bindgen",
 ]
@@ -3071,8 +3170,8 @@ dependencies = [
  "cfg-if",
  "ecdsa",
  "elliptic-curve",
- "sha2 0.10.2",
- "sha3 0.10.1",
+ "sha2 0.10.6",
+ "sha3 0.10.6",
 ]
 
 [[package]]
@@ -3116,7 +3215,7 @@ checksum = "830d08ce1d1d941e6b30645f1a0eb5643013d835ce3779a5fc208261dbe10f55"
 
 [[package]]
 name = "lcli"
-version = "3.2.1"
+version = "3.3.0"
 dependencies = [
  "account_utils",
  "beacon_chain",
@@ -3125,7 +3224,7 @@ dependencies = [
  "clap_utils",
  "deposit_contract",
  "directory",
- "env_logger 0.9.0",
+ "env_logger 0.9.1",
  "environment",
  "eth1_test_rig",
  "eth2",
@@ -3175,9 +3274,9 @@ dependencies = [
 
 [[package]]
 name = "libc"
-version = "0.2.126"
+version = "0.2.137"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "349d5a591cd28b49e1d1037471617a32ddcda5731b99419008085f72d5a53836"
+checksum = "fc7fcc620a3bff7cdd7a365be3376c97191aeaccc2a603e600951e452615bf89"
 
 [[package]]
 name = "libflate"
@@ -3211,9 +3310,9 @@ dependencies = [
 
 [[package]]
 name = "libm"
-version = "0.2.2"
+version = "0.2.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "33a33a362ce288760ec6a508b94caaec573ae7d3bbbd91b87aa0bad4456839db"
+checksum = "292a948cd991e376cf75541fe5b97a1081d713c618b4f1b9500f8844e49eb565"
 
 [[package]]
 name = "libmdbx"
@@ -3239,7 +3338,7 @@ dependencies = [
  "bytes",
  "futures",
  "futures-timer",
- "getrandom 0.2.7",
+ "getrandom 0.2.8",
  "instant",
  "lazy_static",
  "libp2p-core",
@@ -3289,7 +3388,7 @@ dependencies = [
  "prost-build",
  "rand 0.8.5",
  "rw-stream-sink",
- "sha2 0.10.2",
+ "sha2 0.10.6",
  "smallvec",
  "thiserror",
  "unsigned-varint 0.7.1",
@@ -3333,7 +3432,7 @@ dependencies = [
  "prost-build",
  "rand 0.7.3",
  "regex",
- "sha2 0.10.2",
+ "sha2 0.10.6",
  "smallvec",
  "unsigned-varint 0.7.1",
  "wasm-timer",
@@ -3406,7 +3505,7 @@ dependencies = [
  "prost",
  "prost-build",
  "rand 0.8.5",
- "sha2 0.10.2",
+ "sha2 0.10.6",
  "snow",
  "static_assertions",
  "x25519-dalek",
@@ -3452,9 +3551,9 @@ dependencies = [
 
 [[package]]
 name = "libp2p-swarm-derive"
-version = "0.30.0"
+version = "0.30.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1f02622b9dd150011b4eeec387f8bd013189a2f27da08ba363e7c6e606d77a48"
+checksum = "a0eddc4497a8b5a506013c40e8189864f9c3a00db2b25671f428ae9007f3ba32"
 dependencies = [
  "heck",
  "quote",
@@ -3582,7 +3681,7 @@ dependencies = [
 
 [[package]]
 name = "lighthouse"
-version = "3.2.1"
+version = "3.3.0"
 dependencies = [
  "account_manager",
  "account_utils",
@@ -3593,7 +3692,7 @@ dependencies = [
  "clap_utils",
  "database_manager",
  "directory",
- "env_logger 0.9.0",
+ "env_logger 0.9.1",
  "environment",
  "eth1",
  "eth2_hashing",
@@ -3657,7 +3756,7 @@ dependencies = [
  "regex",
  "serde",
  "serde_derive",
- "sha2 0.10.2",
+ "sha2 0.10.6",
  "slog",
  "slog-async",
  "slog-term",
@@ -3688,6 +3787,15 @@ dependencies = [
  "target_info",
 ]
 
+[[package]]
+name = "link-cplusplus"
+version = "1.0.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9272ab7b96c9046fbc5bc56c06c117cb639fe2d509df0c421cad82d2915cf369"
+dependencies = [
+ "cc",
+]
+
 [[package]]
 name = "linked-hash-map"
 version = "0.5.6"
@@ -3717,9 +3825,9 @@ dependencies = [
 
 [[package]]
 name = "lock_api"
-version = "0.4.7"
+version = "0.4.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "327fa5b6a6940e4699ec49a9beae1ea4845c6bab9314e4f84ac68742139d8c53"
+checksum = "435011366fe56583b16cf956f9df0095b405b82d76425bc8981c0e22e60ec4df"
 dependencies = [
  "autocfg 1.1.0",
  "scopeguard",
@@ -3920,23 +4028,23 @@ checksum = "68354c5c6bd36d73ff3feceb05efa59b6acb7626617f4962be322a825e61f79a"
 
 [[package]]
 name = "miniz_oxide"
-version = "0.5.3"
+version = "0.5.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6f5c75688da582b8ffc1f1799e9db273f32133c49e048f614d22ec3256773ccc"
+checksum = "96590ba8f175222643a85693f33d26e9c8a015f599c216509b1a6894af675d34"
 dependencies = [
  "adler",
 ]
 
 [[package]]
 name = "mio"
-version = "0.8.4"
+version = "0.8.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "57ee1c23c7c63b0c9250c339ffdc69255f110b298b901b9f6c82547b7b87caaf"
+checksum = "e5d732bc30207a6423068df043e3d02e0735b155ad7ce1a6f76fe2baa5b158de"
 dependencies = [
  "libc",
  "log",
  "wasi 0.11.0+wasi-snapshot-preview1",
- "windows-sys",
+ "windows-sys 0.42.0",
 ]
 
 [[package]]
@@ -3985,14 +4093,14 @@ dependencies = [
 
 [[package]]
 name = "multihash"
-version = "0.16.2"
+version = "0.16.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e3db354f401db558759dfc1e568d010a5d4146f4d3f637be1275ec4a3cf09689"
+checksum = "1c346cf9999c631f002d8f977c4eaeaa0e6386f16007202308d0b3757522c2cc"
 dependencies = [
  "core2",
- "digest 0.10.3",
+ "digest 0.10.5",
  "multihash-derive",
- "sha2 0.10.2",
+ "sha2 0.10.6",
  "unsigned-varint 0.7.1",
 ]
 
@@ -4125,10 +4233,11 @@ dependencies = [
 
 [[package]]
 name = "nix"
-version = "0.24.2"
+version = "0.25.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "195cdbc1741b8134346d515b3a56a1c94b0912758009cfd53f99ea0f57b065fc"
+checksum = "e322c04a9e3440c327fca7b6c8a63e6890a32fa2ad689db972425f07e0d22abb"
 dependencies = [
+ "autocfg 1.1.0",
  "bitflags",
  "cfg-if",
  "libc",
@@ -4171,6 +4280,25 @@ dependencies = [
  "minimal-lexical",
 ]
 
+[[package]]
+name = "ntapi"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bc51db7b362b205941f71232e56c625156eb9a929f8cf74a428fd5bc094a4afc"
+dependencies = [
+ "winapi",
+]
+
+[[package]]
+name = "nu-ansi-term"
+version = "0.46.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "77a8165726e8236064dbb45459242600304b42a5ea24ee2948e18e023bf7ba84"
+dependencies = [
+ "overload",
+ "winapi",
+]
+
 [[package]]
 name = "num-bigint"
 version = "0.4.3"
@@ -4261,9 +4389,9 @@ dependencies = [
 
 [[package]]
 name = "once_cell"
-version = "1.13.0"
+version = "1.16.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "18a6dbe30758c9f83eb00cbea4ac95966305f5a7772f3f42ebfc7fc7eddbd8e1"
+checksum = "86f0b0d4bf799edbc74508c1e8bf170ff5f41238e5f8225603ca7caaae2b7860"
 
 [[package]]
 name = "oneshot_broadcast"
@@ -4286,9 +4414,9 @@ checksum = "624a8340c38c1b80fd549087862da4ba43e08858af025b236e509b6649fc13d5"
 
 [[package]]
 name = "openssl"
-version = "0.10.41"
+version = "0.10.42"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "618febf65336490dfcf20b73f885f5651a0c89c64c2d4a8c3662585a70bf5bd0"
+checksum = "12fc0523e3bd51a692c8850d075d74dc062ccf251c0110668cbd921917118a13"
 dependencies = [
  "bitflags",
  "cfg-if",
@@ -4327,9 +4455,9 @@ dependencies = [
 
 [[package]]
 name = "openssl-sys"
-version = "0.9.75"
+version = "0.9.77"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e5f9bd0c2710541a3cda73d6f9ac4f1b240de4ae261065d309dbe73d9dceb42f"
+checksum = "b03b84c3b2d099b81f0953422b4d4ad58761589d0229b5506356afca05a3670a"
 dependencies = [
  "autocfg 1.1.0",
  "cc",
@@ -4362,6 +4490,12 @@ dependencies = [
  "types",
 ]
 
+[[package]]
+name = "overload"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b15813163c1d831bf4a13c3610c05c0d03b39feb07f7e09fa234dac9b15aaf39"
+
 [[package]]
 name = "p256"
 version = "0.11.1"
@@ -4370,7 +4504,7 @@ checksum = "51f44edd08f51e2ade572f141051021c5af22677e42b7dd28a88155151c33594"
 dependencies = [
  "ecdsa",
  "elliptic-curve",
- "sha2 0.10.2",
+ "sha2 0.10.6",
 ]
 
 [[package]]
@@ -4389,9 +4523,9 @@ dependencies = [
 
 [[package]]
 name = "parity-scale-codec"
-version = "3.1.5"
+version = "3.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9182e4a71cae089267ab03e67c99368db7cd877baf50f931e5d6d4b71e195ac0"
+checksum = "366e44391a8af4cfd6002ef6ba072bae071a96aafca98d7d448a34c5dca38b6a"
 dependencies = [
  "arrayvec",
  "bitvec 1.0.1",
@@ -4443,7 +4577,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3742b2c103b9f06bc9fff0a37ff4912935851bee6d36f3c02bcc755bcfec228f"
 dependencies = [
  "lock_api",
- "parking_lot_core 0.9.3",
+ "parking_lot_core 0.9.4",
 ]
 
 [[package]]
@@ -4462,22 +4596,22 @@ dependencies = [
 
 [[package]]
 name = "parking_lot_core"
-version = "0.9.3"
+version = "0.9.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "09a279cbf25cb0757810394fbc1e359949b59e348145c643a939a525692e6929"
+checksum = "4dc9e0dc2adc1c69d09143aff38d3d30c5c3f0df0dad82e6d25547af174ebec0"
 dependencies = [
  "cfg-if",
  "libc",
  "redox_syscall",
  "smallvec",
- "windows-sys",
+ "windows-sys 0.42.0",
 ]
 
 [[package]]
 name = "paste"
-version = "1.0.7"
+version = "1.0.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0c520e05135d6e763148b6426a837e239041653ba7becd2e538c076c738025fc"
+checksum = "b1de2e551fb905ac83f73f7aedf2f0cb4a0da7e35efa24a202a936269f1f18e1"
 
 [[package]]
 name = "pbkdf2"
@@ -4514,15 +4648,15 @@ dependencies = [
 
 [[package]]
 name = "percent-encoding"
-version = "2.1.0"
+version = "2.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d4fd5641d01c8f18a23da7b6fe29298ff4b55afcccdf78973b24cf3175fee32e"
+checksum = "478c572c3d73181ff3c2539045f6eb99e5491218eae919370993b890cdbdd98e"
 
 [[package]]
 name = "pest"
-version = "2.3.0"
+version = "2.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4b0560d531d1febc25a3c9398a62a71256c0178f2e3443baedd9ad4bb8c9deb4"
+checksum = "dbc7bc69c062e492337d74d59b120c274fd3d261b6bf6d3207d499b4b379c41a"
 dependencies = [
  "thiserror",
  "ucd-trie",
@@ -4550,18 +4684,18 @@ dependencies = [
 
 [[package]]
 name = "pin-project"
-version = "1.0.11"
+version = "1.0.12"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "78203e83c48cffbe01e4a2d35d566ca4de445d79a85372fc64e378bfc812a260"
+checksum = "ad29a609b6bcd67fee905812e544992d216af9d755757c05ed2d0e15a74c6ecc"
 dependencies = [
  "pin-project-internal",
 ]
 
 [[package]]
 name = "pin-project-internal"
-version = "1.0.11"
+version = "1.0.12"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "710faf75e1b33345361201d36d04e98ac1ed8909151a017ed384700836104c74"
+checksum = "069bdb1e05adc7a8990dce9cc75370895fbe4e3d58b9b73bf1aee56359344a55"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -4598,9 +4732,9 @@ dependencies = [
 
 [[package]]
 name = "pkg-config"
-version = "0.3.25"
+version = "0.3.26"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1df8c4ec4b0627e53bdf214615ad287367e482558cf84b109250b37464dc03ae"
+checksum = "6ac9a59f73473f1b8d852421e59e64809f025994837ef743615c6d0c5b305160"
 
 [[package]]
 name = "platforms"
@@ -4610,9 +4744,9 @@ checksum = "e8d0eef3571242013a0d5dc84861c3ae4a652e56e12adf8bdc26ff5f8cb34c94"
 
 [[package]]
 name = "plotters"
-version = "0.3.3"
+version = "0.3.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "716b4eeb6c4a1d3ecc956f75b43ec2e8e8ba80026413e70a3f41fd3313d3492b"
+checksum = "2538b639e642295546c50fcd545198c9d64ee2a38620a628724a3b266d5fbf97"
 dependencies = [
  "num-traits",
  "plotters-backend",
@@ -4629,9 +4763,9 @@ checksum = "193228616381fecdc1224c62e96946dfbc73ff4384fba576e052ff8c1bea8142"
 
 [[package]]
 name = "plotters-svg"
-version = "0.3.2"
+version = "0.3.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e0918736323d1baff32ee0eade54984f6f201ad7e97d5cfb5d6ab4a358529615"
+checksum = "f9a81d2759aae1dae668f783c308bc5c8ebd191ff4184aaa1b37f65a6ae5a56f"
 dependencies = [
  "plotters-backend",
 ]
@@ -4693,10 +4827,11 @@ dependencies = [
 
 [[package]]
 name = "proc-macro-crate"
-version = "1.1.3"
+version = "1.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e17d47ce914bf4de440332250b0edd23ce48c005f59fab39d3335866b114f11a"
+checksum = "eda0fc3b0fb7c975631757e14d9049da17374063edb6ebbcbc54d880d4fe94e9"
 dependencies = [
+ "once_cell",
  "thiserror",
  "toml",
 ]
@@ -4733,9 +4868,9 @@ checksum = "dbf0c48bc1d91375ae5c3cd81e3722dff1abcf81a30960240640d223f59fe0e5"
 
 [[package]]
 name = "proc-macro2"
-version = "1.0.42"
+version = "1.0.47"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c278e965f1d8cf32d6e0e96de3d3e79712178ae67986d9cf9151f51e95aac89b"
+checksum = "5ea3d908b0e36316caf9e9e2c4625cdde190a7e6f440d794667ed17a1855e725"
 dependencies = [
  "unicode-ident",
 ]
@@ -4754,9 +4889,9 @@ dependencies = [
 
 [[package]]
 name = "prometheus"
-version = "0.13.1"
+version = "0.13.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cface98dfa6d645ea4c789839f176e4b072265d085bfcc48eaa8d137f58d3c39"
+checksum = "449811d15fbdf5ceb5c1144416066429cf82316e2ec8ce0c1f6f8a02e7bbcf8c"
 dependencies = [
  "cfg-if",
  "fnv",
@@ -4769,12 +4904,12 @@ dependencies = [
 
 [[package]]
 name = "prometheus-client"
-version = "0.18.0"
+version = "0.18.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3c473049631c233933d6286c88bbb7be30e62ec534cf99a9ae0079211f7fa603"
+checksum = "83cd1b99916654a69008fd66b4f9397fbe08e6e51dfe23d4417acf5d3b8cb87c"
 dependencies = [
  "dtoa",
- "itoa 1.0.2",
+ "itoa 1.0.4",
  "parking_lot 0.12.1",
  "prometheus-client-derive-text-encode",
 ]
@@ -4870,9 +5005,9 @@ dependencies = [
 
 [[package]]
 name = "protobuf"
-version = "2.27.1"
+version = "2.28.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cf7e6d18738ecd0902d30d1ad232c9125985a3422929b16c65517b38adc14f96"
+checksum = "106dd99e98437432fed6519dedecfade6a06a73bb7b2a1e019fdd2bee5778d94"
 
 [[package]]
 name = "psutil"
@@ -4935,9 +5070,9 @@ dependencies = [
 
 [[package]]
 name = "quote"
-version = "1.0.20"
+version = "1.0.21"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3bcdf212e9776fbcb2d23ab029360416bb1706b1aea2d1a5ba002727cbcab804"
+checksum = "bbe448f377a7d6961e30f5955f9b8d106c3f5e449d493ee1b125c1d43c2b5179"
 dependencies = [
  "proc-macro2",
 ]
@@ -4996,7 +5131,7 @@ checksum = "34af8d1a0e25924bc5b7c43c079c942339d8f0a8b57c39049bef581b46327404"
 dependencies = [
  "libc",
  "rand_chacha 0.3.1",
- "rand_core 0.6.3",
+ "rand_core 0.6.4",
 ]
 
 [[package]]
@@ -5016,7 +5151,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e6c10a63a0fa32252be49d21e7709d4d4baf8d231c2dbce1eaa8141b9b127d88"
 dependencies = [
  "ppv-lite86",
- "rand_core 0.6.3",
+ "rand_core 0.6.4",
 ]
 
 [[package]]
@@ -5030,11 +5165,11 @@ dependencies = [
 
 [[package]]
 name = "rand_core"
-version = "0.6.3"
+version = "0.6.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d34f1408f55294453790c48b2f1ebbb1c5b4b7563eb1f418bcfcfdbb06ebb4e7"
+checksum = "ec0be4795e2f6a28069bec0b5ff3e2ac9bafc99e6a9a7dc3547996c5c816922c"
 dependencies = [
- "getrandom 0.2.7",
+ "getrandom 0.2.8",
 ]
 
 [[package]]
@@ -5052,7 +5187,7 @@ version = "0.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d25bf25ec5ae4a3f1b92f929810509a2f53d7dca2f50b794ff57e3face536c8f"
 dependencies = [
- "rand_core 0.6.3",
+ "rand_core 0.6.4",
 ]
 
 [[package]]
@@ -5094,7 +5229,7 @@ version = "0.4.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b033d837a7cf162d7993aded9304e30a83213c648b6e389db233191f891e5c2b"
 dependencies = [
- "getrandom 0.2.7",
+ "getrandom 0.2.8",
  "redox_syscall",
  "thiserror",
 ]
@@ -5136,9 +5271,9 @@ dependencies = [
 
 [[package]]
 name = "reqwest"
-version = "0.11.11"
+version = "0.11.12"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b75aa69a3f06bbcc66ede33af2af253c6f7a86b1ca0033f60c580a27074fbf92"
+checksum = "431949c384f4e2ae07605ccaa56d1d9d2ecdb5cadd4f9577ccfab29f2e5149fc"
 dependencies = [
  "base64",
  "bytes",
@@ -5153,13 +5288,13 @@ dependencies = [
  "hyper-tls",
  "ipnet",
  "js-sys",
- "lazy_static",
  "log",
  "mime",
  "native-tls",
+ "once_cell",
  "percent-encoding",
  "pin-project-lite 0.2.9",
- "rustls 0.20.6",
+ "rustls 0.20.7",
  "rustls-pemfile",
  "serde",
  "serde_json",
@@ -5167,7 +5302,7 @@ dependencies = [
  "tokio",
  "tokio-native-tls",
  "tokio-rustls 0.23.4",
- "tokio-util 0.7.3",
+ "tokio-util 0.7.4",
  "tower-service",
  "url",
  "wasm-bindgen",
@@ -5221,9 +5356,9 @@ checksum = "3582f63211428f83597b51b2ddb88e2a91a9d52d12831f9d08f5e624e8977422"
 
 [[package]]
 name = "rlp"
-version = "0.5.1"
+version = "0.5.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "999508abb0ae792aabed2460c45b89106d97fe4adac593bdaef433c2605847b5"
+checksum = "bb919243f34364b6bd2fc10ef797edbfa75f33c252e7998527479c6d6b47e1ec"
 dependencies = [
  "bytes",
  "rustc-hex",
@@ -5318,7 +5453,7 @@ version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "bfa0f585226d2e68097d4f95d113b15b83a82e819ab25717ec0590d9584ef366"
 dependencies = [
- "semver 1.0.12",
+ "semver 1.0.14",
 ]
 
 [[package]]
@@ -5336,9 +5471,9 @@ dependencies = [
 
 [[package]]
 name = "rustls"
-version = "0.20.6"
+version = "0.20.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5aab8ee6c7097ed6057f43c187a62418d0c05a4bd5f18b3571db50ee0f9ce033"
+checksum = "539a2bfe908f471bfa933876bd1eb6a19cf2176d375f82ef7f99530a40e48c2c"
 dependencies = [
  "log",
  "ring",
@@ -5348,18 +5483,18 @@ dependencies = [
 
 [[package]]
 name = "rustls-pemfile"
-version = "1.0.0"
+version = "1.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e7522c9de787ff061458fe9a829dc790a3f5b22dc571694fc5883f448b94d9a9"
+checksum = "0864aeff53f8c05aa08d86e5ef839d3dfcf07aeba2db32f12db0ef716e87bd55"
 dependencies = [
  "base64",
 ]
 
 [[package]]
 name = "rustversion"
-version = "1.0.8"
+version = "1.0.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "24c8ad4f0c00e1eb5bc7614d236a7f1300e3dbd76b68cac8e06fb00b015ad8d8"
+checksum = "97477e48b4cf8603ad5f7aaf897467cf42ab4218a38ef76fb14c2d6773a6d6a8"
 
 [[package]]
 name = "rw-stream-sink"
@@ -5374,9 +5509,9 @@ dependencies = [
 
 [[package]]
 name = "ryu"
-version = "1.0.10"
+version = "1.0.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f3f6f92acf49d1b98f7a81226834412ada05458b7364277387724a237f062695"
+checksum = "4501abdff3ae82a1c1b477a17252eb69cee9e66eb915c1abaa4f44d873df9f09"
 
 [[package]]
 name = "safe_arith"
@@ -5413,7 +5548,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "88d6731146462ea25d9244b2ed5fd1d716d25c52e4d54aa4fb0f3c4e9854dbe2"
 dependencies = [
  "lazy_static",
- "windows-sys",
+ "windows-sys 0.36.1",
 ]
 
 [[package]]
@@ -5427,9 +5562,9 @@ dependencies = [
 
 [[package]]
 name = "scoped-tls"
-version = "1.0.0"
+version = "1.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ea6a9290e3c9cf0f18145ef7ffa62d68ee0bf5fcd651017e586dc7fd5da448c2"
+checksum = "e1cf6437eb19a8f4a6cc0f7dca544973b0b78843adbfeb3683d1a94a0024a294"
 
 [[package]]
 name = "scopeguard"
@@ -5437,6 +5572,12 @@ version = "1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d29ab0c6d3fc0ee92fe66e2d99f700eab17a8d57d1c1d3b748380fb20baa78cd"
 
+[[package]]
+name = "scratch"
+version = "1.0.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9c8132065adcfd6e02db789d9285a0deb2f3fcb04002865ab67d5fb103533898"
+
 [[package]]
 name = "scrypt"
 version = "0.7.0"
@@ -5503,9 +5644,9 @@ dependencies = [
 
 [[package]]
 name = "security-framework"
-version = "2.6.1"
+version = "2.7.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2dc14f172faf8a0194a3aded622712b0de276821addc574fa54fc0a1167e10dc"
+checksum = "2bc1bb97804af6631813c55739f771071e0f2ed33ee20b68c86ec505d906356c"
 dependencies = [
  "bitflags",
  "core-foundation",
@@ -5544,9 +5685,9 @@ dependencies = [
 
 [[package]]
 name = "semver"
-version = "1.0.12"
+version = "1.0.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a2333e6df6d6598f2b1974829f853c2b4c5f4a6e503c10af918081aa6f8564e1"
+checksum = "e25dfac463d778e353db5be2449d1cce89bd6fd23c9f1ea21310ce6e5a1b29c4"
 
 [[package]]
 name = "semver-parser"
@@ -5579,13 +5720,22 @@ dependencies = [
 
 [[package]]
 name = "serde"
-version = "1.0.140"
+version = "1.0.147"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "fc855a42c7967b7c369eb5860f7164ef1f6f81c20c7cc1141f2a604e18723b03"
+checksum = "d193d69bae983fc11a79df82342761dfbf28a99fc8d203dca4c3c1b590948965"
 dependencies = [
  "serde_derive",
 ]
 
+[[package]]
+name = "serde-big-array"
+version = "0.3.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cd31f59f6fe2b0c055371bb2f16d7f0aa7d8881676c04a55b1596d1a17cd10a4"
+dependencies = [
+ "serde",
+]
+
 [[package]]
 name = "serde_array_query"
 version = "0.1.0"
@@ -5608,9 +5758,9 @@ dependencies = [
 
 [[package]]
 name = "serde_derive"
-version = "1.0.140"
+version = "1.0.147"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6f2122636b9fe3b81f1cb25099fcf2d3f542cdb1d45940d56c713158884a05da"
+checksum = "4f1d362ca8fc9c3e3a7484440752472d68a6caa98f1ab81d99b5dfe517cec852"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -5619,20 +5769,20 @@ dependencies = [
 
 [[package]]
 name = "serde_json"
-version = "1.0.82"
+version = "1.0.87"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "82c2c1fdcd807d1098552c5b9a36e425e42e9fbd7c6a37a8425f390f781f7fa7"
+checksum = "6ce777b7b150d76b9cf60d28b55f5847135a003f7d7350c6be7a773508ce7d45"
 dependencies = [
- "itoa 1.0.2",
+ "itoa 1.0.4",
  "ryu",
  "serde",
 ]
 
 [[package]]
 name = "serde_repr"
-version = "0.1.8"
+version = "0.1.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a2ad84e47328a31223de7fed7a4f5087f2d6ddfe586cf3ca25b7a165bc0a5aed"
+checksum = "1fe39d9fbb0ebf5eb2c7cb7e2a47e4f462fad1379f1166b8ae49ad9eae89a7ca"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -5646,7 +5796,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d3491c14715ca2294c4d6a88f15e84739788c1d030eed8c110436aafdaa2f3fd"
 dependencies = [
  "form_urlencoded",
- "itoa 1.0.2",
+ "itoa 1.0.4",
  "ryu",
  "serde",
 ]
@@ -5706,7 +5856,18 @@ checksum = "028f48d513f9678cda28f6e4064755b3fbb2af6acd672f2c209b62323f7aea0f"
 dependencies = [
  "cfg-if",
  "cpufeatures",
- "digest 0.10.3",
+ "digest 0.10.5",
+]
+
+[[package]]
+name = "sha1"
+version = "0.10.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f04293dc80c3993519f2d7f6f511707ee7094fe0c6d3406feb330cdb3540eba3"
+dependencies = [
+ "cfg-if",
+ "cpufeatures",
+ "digest 0.10.5",
 ]
 
 [[package]]
@@ -5724,13 +5885,13 @@ dependencies = [
 
 [[package]]
 name = "sha2"
-version = "0.10.2"
+version = "0.10.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "55deaec60f81eefe3cce0dc50bda92d6d8e88f2a27df7c5033b42afeb1ed2676"
+checksum = "82e6b795fe2e3b1e845bafcb27aa35405c4d47cdfc92af5fc8d3002f76cebdc0"
 dependencies = [
  "cfg-if",
  "cpufeatures",
- "digest 0.10.3",
+ "digest 0.10.5",
 ]
 
 [[package]]
@@ -5747,11 +5908,11 @@ dependencies = [
 
 [[package]]
 name = "sha3"
-version = "0.10.1"
+version = "0.10.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "881bf8156c87b6301fc5ca6b27f11eeb2761224c7081e69b409d5a1951a70c86"
+checksum = "bdf0c33fae925bdc080598b84bc15c55e7b9a4a43b3c704da051f977469691c9"
 dependencies = [
- "digest 0.10.3",
+ "digest 0.10.5",
  "keccak",
 ]
 
@@ -5781,12 +5942,12 @@ dependencies = [
 
 [[package]]
 name = "signature"
-version = "1.6.3"
+version = "1.6.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "deb766570a2825fa972bceff0d195727876a9cdf2460ab2e52d455dc2de47fd9"
+checksum = "74233d3b3b2f6d4b006dc19dee745e73e2a6bfb6f93607cd3b02bd5b00797d7c"
 dependencies = [
- "digest 0.10.3",
- "rand_core 0.6.3",
+ "digest 0.10.5",
+ "rand_core 0.6.4",
 ]
 
 [[package]]
@@ -5798,7 +5959,7 @@ dependencies = [
  "num-bigint",
  "num-traits",
  "thiserror",
- "time 0.3.11",
+ "time 0.3.16",
 ]
 
 [[package]]
@@ -5806,7 +5967,7 @@ name = "simulator"
 version = "0.2.0"
 dependencies = [
  "clap",
- "env_logger 0.9.0",
+ "env_logger 0.9.1",
  "eth1",
  "eth1_test_rig",
  "execution_layer",
@@ -5924,7 +6085,7 @@ dependencies = [
  "serde",
  "serde_json",
  "slog",
- "time 0.3.11",
+ "time 0.3.16",
 ]
 
 [[package]]
@@ -5969,7 +6130,7 @@ dependencies = [
  "slog",
  "term",
  "thread_local",
- "time 0.3.11",
+ "time 0.3.16",
 ]
 
 [[package]]
@@ -6008,9 +6169,9 @@ dependencies = [
 
 [[package]]
 name = "smallvec"
-version = "1.9.0"
+version = "1.10.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2fd0db749597d91ff862fd1d55ea87f7855a744a8425a64695b6fca237d1dad1"
+checksum = "a507befe795404456341dfab10cef66ead4c041f62b8b11bbb92bffe5d0953e0"
 
 [[package]]
 name = "snap"
@@ -6028,18 +6189,18 @@ dependencies = [
  "blake2",
  "chacha20poly1305",
  "curve25519-dalek 4.0.0-pre.1",
- "rand_core 0.6.3",
+ "rand_core 0.6.4",
  "ring",
  "rustc_version 0.4.0",
- "sha2 0.10.2",
+ "sha2 0.10.6",
  "subtle",
 ]
 
 [[package]]
 name = "socket2"
-version = "0.4.4"
+version = "0.4.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "66d72b759436ae32898a2af0a14218dbf55efde3feeb170eb623637db85ee1e0"
+checksum = "02e2d2db9033d13a1567121ddd7a095ee144db4e1ca1b1bda3419bc0da294ebd"
 dependencies = [
  "libc",
  "winapi",
@@ -6110,7 +6271,7 @@ dependencies = [
  "beacon_chain",
  "bls",
  "derivative",
- "env_logger 0.9.0",
+ "env_logger 0.9.1",
  "eth2_hashing",
  "eth2_ssz",
  "eth2_ssz_derive",
@@ -6195,9 +6356,9 @@ dependencies = [
 
 [[package]]
 name = "strum_macros"
-version = "0.24.2"
+version = "0.24.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4faebde00e8ff94316c01800f9054fd2ba77d30d9e922541913051d1d978918b"
+checksum = "1e385be0d24f186b4ce2f9982191e7101bb737312ad61c1f2f984f34bcf85d59"
 dependencies = [
  "heck",
  "proc-macro2",
@@ -6251,9 +6412,9 @@ dependencies = [
 
 [[package]]
 name = "syn"
-version = "1.0.98"
+version = "1.0.103"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c50aef8a904de4c23c788f104b7dddc7d6f79c647c7c8ce4cc8f73eb0ca773dd"
+checksum = "a864042229133ada95abf3b54fdc62ef5ccabe9515b64717bcb9a1919e59445d"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -6278,6 +6439,34 @@ dependencies = [
  "unicode-xid",
 ]
 
+[[package]]
+name = "sysinfo"
+version = "0.26.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c375d5fd899e32847b8566e10598d6e9f1d9b55ec6de3cdf9e7da4bdc51371bc"
+dependencies = [
+ "cfg-if",
+ "core-foundation-sys",
+ "libc",
+ "ntapi",
+ "once_cell",
+ "rayon",
+ "winapi",
+]
+
+[[package]]
+name = "system_health"
+version = "0.1.0"
+dependencies = [
+ "lighthouse_network",
+ "parking_lot 0.12.1",
+ "serde",
+ "serde_derive",
+ "serde_json",
+ "sysinfo",
+ "types",
+]
+
 [[package]]
 name = "take_mut"
 version = "0.2.2"
@@ -6377,18 +6566,18 @@ dependencies = [
 
 [[package]]
 name = "thiserror"
-version = "1.0.31"
+version = "1.0.37"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "bd829fe32373d27f76265620b5309d0340cb8550f523c1dda251d6298069069a"
+checksum = "10deb33631e3c9018b9baf9dcbbc4f737320d2b576bac10f6aefa048fa407e3e"
 dependencies = [
  "thiserror-impl",
 ]
 
 [[package]]
 name = "thiserror-impl"
-version = "1.0.31"
+version = "1.0.37"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0396bc89e626244658bef819e22d0cc459e795a5ebe878e6ec336d1674a8d79a"
+checksum = "982d17546b47146b28f7c22e3d08465f6b8903d0ea13c1660d9d84a6e7adcdbb"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -6426,21 +6615,32 @@ dependencies = [
 
 [[package]]
 name = "time"
-version = "0.3.11"
+version = "0.3.16"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "72c91f41dcb2f096c05f0873d667dceec1087ce5bcf984ec8ffb19acddbb3217"
+checksum = "0fab5c8b9980850e06d92ddbe3ab839c062c801f3927c0fb8abd6fc8e918fbca"
 dependencies = [
- "itoa 1.0.2",
+ "itoa 1.0.4",
  "libc",
  "num_threads",
+ "serde",
+ "time-core",
  "time-macros",
 ]
 
 [[package]]
-name = "time-macros"
-version = "0.2.4"
+name = "time-core"
+version = "0.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "42657b1a6f4d817cda8e7a0ace261fe0cc946cf3a80314390b22cc61ae080792"
+checksum = "2e153e1f1acaef8acc537e68b44906d2db6436e2b35ac2c6b42640fff91f00fd"
+
+[[package]]
+name = "time-macros"
+version = "0.2.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "65bb801831d812c562ae7d2bfb531f26e66e4e1f6b17307ba4149c5064710e5b"
+dependencies = [
+ "time-core",
+]
 
 [[package]]
 name = "timer"
@@ -6508,9 +6708,9 @@ checksum = "cda74da7e1a664f795bb1f8a87ec406fb89a02522cf6e50620d016add6dbbf5c"
 
 [[package]]
 name = "tokio"
-version = "1.20.1"
+version = "1.21.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7a8325f63a7d4774dd041e363b2409ed1c5cbbd0f867795e661df066b2b0a581"
+checksum = "a9e03c497dc955702ba729190dc4aac6f2a0ce97f913e5b1b5912fc5039d9099"
 dependencies = [
  "autocfg 1.1.0",
  "bytes",
@@ -6518,7 +6718,6 @@ dependencies = [
  "memchr",
  "mio",
  "num_cpus",
- "once_cell",
  "parking_lot 0.12.1",
  "pin-project-lite 0.2.9",
  "signal-hook-registry",
@@ -6575,21 +6774,21 @@ version = "0.23.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c43ee83903113e03984cb9e5cebe6c04a5116269e900e3ddba8f068a62adda59"
 dependencies = [
- "rustls 0.20.6",
+ "rustls 0.20.7",
  "tokio",
  "webpki 0.22.0",
 ]
 
 [[package]]
 name = "tokio-stream"
-version = "0.1.9"
+version = "0.1.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "df54d54117d6fdc4e4fea40fe1e4e566b3505700e148a6827e59b34b0d2600d9"
+checksum = "d660770404473ccd7bc9f8b28494a811bc18542b915c0855c51e8f419d5223ce"
 dependencies = [
  "futures-core",
  "pin-project-lite 0.2.9",
  "tokio",
- "tokio-util 0.7.3",
+ "tokio-util 0.7.4",
 ]
 
 [[package]]
@@ -6613,7 +6812,7 @@ checksum = "f714dd15bead90401d77e04243611caec13726c2408afd5b31901dfcdcb3b181"
 dependencies = [
  "futures-util",
  "log",
- "rustls 0.20.6",
+ "rustls 0.20.7",
  "tokio",
  "tokio-rustls 0.23.4",
  "tungstenite 0.17.3",
@@ -6639,9 +6838,9 @@ dependencies = [
 
 [[package]]
 name = "tokio-util"
-version = "0.7.3"
+version = "0.7.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cc463cd8deddc3770d20f9852143d50bf6094e640b485cb2e189a2099085ff45"
+checksum = "0bb2e075f03b3d66d8d8785356224ba688d2906a371015e225beeb65ca92c740"
 dependencies = [
  "bytes",
  "futures-core",
@@ -6697,9 +6896,9 @@ dependencies = [
 
 [[package]]
 name = "tower-layer"
-version = "0.3.1"
+version = "0.3.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "343bc9466d3fe6b0f960ef45960509f84480bf4fd96f92901afe7ff3df9d3a62"
+checksum = "c20c8dbed6283a09604c3e69b4b7eeb54e298b8a600d4d5ecb5ad39de609f1d0"
 
 [[package]]
 name = "tower-service"
@@ -6709,9 +6908,9 @@ checksum = "b6bc1c9ce2b5135ac7f93c72918fc37feb872bdc6a5533a8b85eb4b86bfdae52"
 
 [[package]]
 name = "tracing"
-version = "0.1.35"
+version = "0.1.37"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a400e31aa60b9d44a52a8ee0343b5b18566b03a8321e0d321f695cf56e940160"
+checksum = "8ce8c33a8d48bd45d624a6e523445fd21ec13d3653cd51f681abf67418f54eb8"
 dependencies = [
  "cfg-if",
  "log",
@@ -6722,9 +6921,9 @@ dependencies = [
 
 [[package]]
 name = "tracing-attributes"
-version = "0.1.22"
+version = "0.1.23"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "11c75893af559bc8e10716548bdef5cb2b983f8e637db9d0e15126b61b484ee2"
+checksum = "4017f8f45139870ca7e672686113917c71c7a6e02d4924eda67186083c03081a"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -6733,9 +6932,9 @@ dependencies = [
 
 [[package]]
 name = "tracing-core"
-version = "0.1.28"
+version = "0.1.30"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7b7358be39f2f274f322d2aaed611acc57f382e8eb1e5b48cb9ae30933495ce7"
+checksum = "24eb03ba0eab1fd845050058ce5e616558e8f8d8fca633e6b163fe25c797213a"
 dependencies = [
  "once_cell",
  "valuable",
@@ -6764,12 +6963,12 @@ dependencies = [
 
 [[package]]
 name = "tracing-subscriber"
-version = "0.3.15"
+version = "0.3.16"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "60db860322da191b40952ad9affe65ea23e7dd6a5c442c2c42865810c6ab8e6b"
+checksum = "a6176eae26dd70d0c919749377897b54a9276bd7061339665dd68777926b5a70"
 dependencies = [
- "ansi_term",
  "matchers",
+ "nu-ansi-term",
  "once_cell",
  "regex",
  "sharded-slab",
@@ -6836,7 +7035,7 @@ dependencies = [
  "futures-channel",
  "futures-io",
  "futures-util",
- "idna",
+ "idna 0.2.3",
  "ipnet",
  "lazy_static",
  "log",
@@ -6906,7 +7105,7 @@ dependencies = [
  "httparse",
  "log",
  "rand 0.8.5",
- "rustls 0.20.6",
+ "rustls 0.20.7",
  "sha-1 0.10.0",
  "thiserror",
  "url",
@@ -6955,6 +7154,7 @@ dependencies = [
  "lazy_static",
  "log",
  "maplit",
+ "merkle_proof",
  "parking_lot 0.12.1",
  "rand 0.8.5",
  "rand_xorshift",
@@ -6963,6 +7163,7 @@ dependencies = [
  "rusqlite",
  "safe_arith",
  "serde",
+ "serde-big-array",
  "serde_derive",
  "serde_json",
  "serde_with",
@@ -6981,15 +7182,15 @@ dependencies = [
 
 [[package]]
 name = "ucd-trie"
-version = "0.1.4"
+version = "0.1.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "89570599c4fe5585de2b388aab47e99f7fa4e9238a1399f707a02e356058141c"
+checksum = "9e79c4d996edb816c91e4308506774452e55e95c3c9de07b6729e17e15a5ef81"
 
 [[package]]
 name = "uint"
-version = "0.9.3"
+version = "0.9.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "12f03af7ccf01dd611cc450a0d10dbc9b745770d096473e2faf0ca6e2d66d1e0"
+checksum = "a45526d29728d135c2900b0d30573fe3ee79fceb12ef534c7bb30e810a91b601"
 dependencies = [
  "arbitrary",
  "byteorder",
@@ -7021,30 +7222,30 @@ checksum = "099b7128301d285f79ddd55b9a83d5e6b9e97c92e0ea0daebee7263e932de992"
 
 [[package]]
 name = "unicode-ident"
-version = "1.0.2"
+version = "1.0.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "15c61ba63f9235225a22310255a29b806b907c9b8c964bcbd0a2c70f3f2deea7"
+checksum = "6ceab39d59e4c9499d4e5a8ee0e2735b891bb7308ac83dfb4e80cad195c9f6f3"
 
 [[package]]
 name = "unicode-normalization"
-version = "0.1.21"
+version = "0.1.22"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "854cbdc4f7bc6ae19c820d44abdc3277ac3e1b2b93db20a636825d9322fb60e6"
+checksum = "5c5713f0fc4b5db668a2ac63cdb7bb4469d8c9fed047b1d0292cc7b0ce2ba921"
 dependencies = [
  "tinyvec",
 ]
 
 [[package]]
 name = "unicode-width"
-version = "0.1.9"
+version = "0.1.10"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3ed742d4ea2bd1176e236172c8429aaf54486e7ac098db29ffe6529e0ce50973"
+checksum = "c0edd1e5b14653f783770bce4a4dabb4a5108a5370a5f5d8cfe8710c361f6c8b"
 
 [[package]]
 name = "unicode-xid"
-version = "0.2.3"
+version = "0.2.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "957e51f3646910546462e67d5f7599b9e4fb8acdd304b087a6494730f9eebf04"
+checksum = "f962df74c8c05a667b5ee8bcf162993134c104e96440b663c8daa176dc772d8c"
 
 [[package]]
 name = "universal-hash"
@@ -7088,13 +7289,12 @@ version = "0.1.0"
 
 [[package]]
 name = "url"
-version = "2.2.2"
+version = "2.3.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a507c383b2d33b5fc35d1861e77e6b383d158b2da5e14fe51b83dfedf6fd578c"
+checksum = "0d68c799ae75762b8c3fe375feb6600ef5602c883c5d21eb51c09f22b83c4643"
 dependencies = [
  "form_urlencoded",
- "idna",
- "matches",
+ "idna 0.3.0",
  "percent-encoding",
 ]
 
@@ -7110,7 +7310,7 @@ version = "0.8.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "bc5cf98d8186244414c848017f0e2676b3fcb46807f6668a97dfe67359a3c4b7"
 dependencies = [
- "getrandom 0.2.7",
+ "getrandom 0.2.8",
  "serde",
 ]
 
@@ -7156,6 +7356,8 @@ dependencies = [
  "slashing_protection",
  "slog",
  "slot_clock",
+ "sysinfo",
+ "system_health",
  "task_executor",
  "tempfile",
  "tokio",
@@ -7303,9 +7505,9 @@ checksum = "9c8d87e72b64a3b4db28d11ce29237c246188f4f51057d65a7eab63b7987e423"
 
 [[package]]
 name = "wasm-bindgen"
-version = "0.2.82"
+version = "0.2.83"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "fc7652e3f6c4706c8d9cd54832c4a4ccb9b5336e2c3bd154d5cccfbf1c1f5f7d"
+checksum = "eaf9f5aceeec8be17c128b2e93e031fb8a4d469bb9c4ae2d7dc1888b26887268"
 dependencies = [
  "cfg-if",
  "wasm-bindgen-macro",
@@ -7313,9 +7515,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-backend"
-version = "0.2.82"
+version = "0.2.83"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "662cd44805586bd52971b9586b1df85cdbbd9112e4ef4d8f41559c334dc6ac3f"
+checksum = "4c8ffb332579b0557b52d268b91feab8df3615f265d5270fec2a8c95b17c1142"
 dependencies = [
  "bumpalo",
  "log",
@@ -7328,9 +7530,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-futures"
-version = "0.4.32"
+version = "0.4.33"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "fa76fb221a1f8acddf5b54ace85912606980ad661ac7a503b4570ffd3a624dad"
+checksum = "23639446165ca5a5de86ae1d8896b737ae80319560fbaa4c2887b7da6e7ebd7d"
 dependencies = [
  "cfg-if",
  "js-sys",
@@ -7340,9 +7542,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-macro"
-version = "0.2.82"
+version = "0.2.83"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b260f13d3012071dfb1512849c033b1925038373aea48ced3012c09df952c602"
+checksum = "052be0f94026e6cbc75cdefc9bae13fd6052cdcaf532fa6c45e7ae33a1e6c810"
 dependencies = [
  "quote",
  "wasm-bindgen-macro-support",
@@ -7350,9 +7552,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-macro-support"
-version = "0.2.82"
+version = "0.2.83"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5be8e654bdd9b79216c2929ab90721aa82faf65c48cdf08bdc4e7f51357b80da"
+checksum = "07bc0c051dc5f23e307b13285f9d75df86bfdf816c5721e573dec1f9b8aa193c"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -7363,15 +7565,15 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-shared"
-version = "0.2.82"
+version = "0.2.83"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6598dd0bd3c7d51095ff6531a5b23e02acdc81804e30d8f07afb77b7215a140a"
+checksum = "1c38c045535d93ec4f0b4defec448e4291638ee608530863b1e2ba115d4fff7f"
 
 [[package]]
 name = "wasm-bindgen-test"
-version = "0.3.32"
+version = "0.3.33"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "513df541345bb9fcc07417775f3d51bbb677daf307d8035c0afafd87dc2e6599"
+checksum = "09d2fff962180c3fadf677438054b1db62bee4aa32af26a45388af07d1287e1d"
 dependencies = [
  "console_error_panic_hook",
  "js-sys",
@@ -7383,9 +7585,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-test-macro"
-version = "0.3.32"
+version = "0.3.33"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6150d36a03e90a3cf6c12650be10626a9902d70c5270fd47d7a47e5389a10d56"
+checksum = "4683da3dfc016f704c9f82cf401520c4f1cb3ee440f7f52b3d6ac29506a49ca7"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -7408,9 +7610,9 @@ dependencies = [
 
 [[package]]
 name = "web-sys"
-version = "0.3.59"
+version = "0.3.60"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ed055ab27f941423197eb86b2035720b1a3ce40504df082cac2ecc6ed73335a1"
+checksum = "bcda906d8be16e728fd5adc5b729afad4e444e106ab28cd1c7256e54fa61510f"
 dependencies = [
  "js-sys",
  "wasm-bindgen",
@@ -7432,7 +7634,7 @@ dependencies = [
  "futures-timer",
  "headers",
  "hex",
- "idna",
+ "idna 0.2.3",
  "jsonrpc-core",
  "log",
  "once_cell",
@@ -7510,22 +7712,22 @@ dependencies = [
 
 [[package]]
 name = "webpki-roots"
-version = "0.22.4"
+version = "0.22.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f1c760f0d366a6c24a02ed7816e23e691f5d92291f94d15e836006fd11b04daf"
+checksum = "368bfe657969fb01238bb756d351dcade285e0f6fcbd36dcb23359a5169975be"
 dependencies = [
  "webpki 0.22.0",
 ]
 
 [[package]]
 name = "which"
-version = "4.2.5"
+version = "4.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5c4fb54e6113b6a8772ee41c3404fb0301ac79604489467e0a9ce1f3e97c24ae"
+checksum = "1c831fbbee9e129a8cf93e7747a82da9d95ba8e16621cae60ec2cdc849bacb7b"
 dependencies = [
  "either",
- "lazy_static",
  "libc",
+ "once_cell",
 ]
 
 [[package]]
@@ -7589,43 +7791,100 @@ version = "0.36.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ea04155a16a59f9eab786fe12a4a450e75cdb175f9e0d80da1e17db09f55b8d2"
 dependencies = [
- "windows_aarch64_msvc",
- "windows_i686_gnu",
- "windows_i686_msvc",
- "windows_x86_64_gnu",
- "windows_x86_64_msvc",
+ "windows_aarch64_msvc 0.36.1",
+ "windows_i686_gnu 0.36.1",
+ "windows_i686_msvc 0.36.1",
+ "windows_x86_64_gnu 0.36.1",
+ "windows_x86_64_msvc 0.36.1",
 ]
 
+[[package]]
+name = "windows-sys"
+version = "0.42.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5a3e1820f08b8513f676f7ab6c1f99ff312fb97b553d30ff4dd86f9f15728aa7"
+dependencies = [
+ "windows_aarch64_gnullvm",
+ "windows_aarch64_msvc 0.42.0",
+ "windows_i686_gnu 0.42.0",
+ "windows_i686_msvc 0.42.0",
+ "windows_x86_64_gnu 0.42.0",
+ "windows_x86_64_gnullvm",
+ "windows_x86_64_msvc 0.42.0",
+]
+
+[[package]]
+name = "windows_aarch64_gnullvm"
+version = "0.42.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "41d2aa71f6f0cbe00ae5167d90ef3cfe66527d6f613ca78ac8024c3ccab9a19e"
+
 [[package]]
 name = "windows_aarch64_msvc"
 version = "0.36.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9bb8c3fd39ade2d67e9874ac4f3db21f0d710bee00fe7cab16949ec184eeaa47"
 
+[[package]]
+name = "windows_aarch64_msvc"
+version = "0.42.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "dd0f252f5a35cac83d6311b2e795981f5ee6e67eb1f9a7f64eb4500fbc4dcdb4"
+
 [[package]]
 name = "windows_i686_gnu"
 version = "0.36.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "180e6ccf01daf4c426b846dfc66db1fc518f074baa793aa7d9b9aaeffad6a3b6"
 
+[[package]]
+name = "windows_i686_gnu"
+version = "0.42.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fbeae19f6716841636c28d695375df17562ca208b2b7d0dc47635a50ae6c5de7"
+
 [[package]]
 name = "windows_i686_msvc"
 version = "0.36.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e2e7917148b2812d1eeafaeb22a97e4813dfa60a3f8f78ebe204bcc88f12f024"
 
+[[package]]
+name = "windows_i686_msvc"
+version = "0.42.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "84c12f65daa39dd2babe6e442988fc329d6243fdce47d7d2d155b8d874862246"
+
 [[package]]
 name = "windows_x86_64_gnu"
 version = "0.36.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "4dcd171b8776c41b97521e5da127a2d86ad280114807d0b2ab1e462bc764d9e1"
 
+[[package]]
+name = "windows_x86_64_gnu"
+version = "0.42.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bf7b1b21b5362cbc318f686150e5bcea75ecedc74dd157d874d754a2ca44b0ed"
+
+[[package]]
+name = "windows_x86_64_gnullvm"
+version = "0.42.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "09d525d2ba30eeb3297665bd434a54297e4170c7f1a44cad4ef58095b4cd2028"
+
 [[package]]
 name = "windows_x86_64_msvc"
 version = "0.36.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c811ca4a8c853ef420abd8592ba53ddbbac90410fab6903b3e79972a631f7680"
 
+[[package]]
+name = "windows_x86_64_msvc"
+version = "0.42.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f40009d85759725a34da6d89a94e63d7bdc50a862acf0dbc7c8e488f1edcb6f5"
+
 [[package]]
 name = "winreg"
 version = "0.7.0"
@@ -7714,9 +7973,9 @@ dependencies = [
 
 [[package]]
 name = "yamux"
-version = "0.10.1"
+version = "0.10.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0c0608f53c1dc0bad505d03a34bbd49fbf2ad7b51eb036123e896365532745a1"
+checksum = "e5d9ba232399af1783a58d8eb26f6b5006fbefe2dc9ef36bd283324792d03ea5"
 dependencies = [
  "futures",
  "log",
diff --git a/Cargo.toml b/Cargo.toml
index d315d689f..f60db6455 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -37,6 +37,7 @@ members = [
     "common/oneshot_broadcast",
     "common/sensitive_url",
     "common/slot_clock",
+    "common/system_health",
     "common/task_executor",
     "common/target_check",
     "common/test_random_derive",
diff --git a/account_manager/src/validator/create.rs b/account_manager/src/validator/create.rs
index bbd2cbc99..da0112105 100644
--- a/account_manager/src/validator/create.rs
+++ b/account_manager/src/validator/create.rs
@@ -114,7 +114,7 @@ pub fn cli_app<'a, 'b>() -> App<'a, 'b> {
 
 pub fn cli_run<T: EthSpec>(
     matches: &ArgMatches,
-    mut env: Environment<T>,
+    env: Environment<T>,
     validator_dir: PathBuf,
 ) -> Result<(), String> {
     let spec = env.core_context().eth2_config.spec;
diff --git a/beacon_node/Cargo.toml b/beacon_node/Cargo.toml
index 18973cb9d..309d7a83f 100644
--- a/beacon_node/Cargo.toml
+++ b/beacon_node/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "beacon_node"
-version = "3.2.1"
+version = "3.3.0"
 authors = ["Paul Hauner <paul@paulhauner.com>", "Age Manning <Age@AgeManning.com"]
 edition = "2021"
 
diff --git a/beacon_node/beacon_chain/src/beacon_chain.rs b/beacon_node/beacon_chain/src/beacon_chain.rs
index 8c2cc8707..91f142686 100644
--- a/beacon_node/beacon_chain/src/beacon_chain.rs
+++ b/beacon_node/beacon_chain/src/beacon_chain.rs
@@ -20,8 +20,7 @@ use crate::errors::{BeaconChainError as Error, BlockProductionError};
 use crate::eth1_chain::{Eth1Chain, Eth1ChainBackend};
 use crate::eth1_finalization_cache::{Eth1FinalizationCache, Eth1FinalizationData};
 use crate::events::ServerSentEventHandler;
-use crate::execution_payload::get_execution_payload;
-use crate::execution_payload::PreparePayloadHandle;
+use crate::execution_payload::{get_execution_payload, NotifyExecutionLayer, PreparePayloadHandle};
 use crate::fork_choice_signal::{ForkChoiceSignalRx, ForkChoiceSignalTx, ForkChoiceWaitResult};
 use crate::head_tracker::HeadTracker;
 use crate::historical_blocks::HistoricalBlockError;
@@ -80,7 +79,7 @@ use ssz::Encode;
 #[cfg(feature = "withdrawals")]
 use state_processing::per_block_processing::get_expected_withdrawals;
 use state_processing::{
-    common::{get_attesting_indices_from_state, get_indexed_attestation},
+    common::get_attesting_indices_from_state,
     per_block_processing,
     per_block_processing::{
         errors::AttestationValidationError, verify_attestation_for_block_inclusion,
@@ -1047,6 +1046,46 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
         Ok(self.store.get_state(state_root, slot)?)
     }
 
+    /// Run a function with mutable access to a state for `block_root`.
+    ///
+    /// The primary purpose of this function is to borrow a state with its tree hash cache
+    /// from the snapshot cache *without moving it*. This means that calls to this function should
+    /// be kept to an absolute minimum, because holding the snapshot cache lock has the ability
+    /// to delay block import.
+    ///
+    /// If there is no appropriate state in the snapshot cache then one will be loaded from disk.
+    /// If no state is found on disk then `Ok(None)` will be returned.
+    ///
+    /// The 2nd parameter to the closure is a bool indicating whether the snapshot cache was used,
+    /// which can inform logging/metrics.
+    ///
+    /// NOTE: the medium-term plan is to delete this function and the snapshot cache in favour
+    /// of `tree-states`, where all caches are CoW and everything is good in the world.
+    pub fn with_mutable_state_for_block<F, V, Payload: AbstractExecPayload<T::EthSpec>>(
+        &self,
+        block: &SignedBeaconBlock<T::EthSpec, Payload>,
+        block_root: Hash256,
+        f: F,
+    ) -> Result<Option<V>, Error>
+    where
+        F: FnOnce(&mut BeaconState<T::EthSpec>, bool) -> Result<V, Error>,
+    {
+        if let Some(state) = self
+            .snapshot_cache
+            .try_write_for(BLOCK_PROCESSING_CACHE_LOCK_TIMEOUT)
+            .ok_or(Error::SnapshotCacheLockTimeout)?
+            .borrow_unadvanced_state_mut(block_root)
+        {
+            let cache_hit = true;
+            f(state, cache_hit).map(Some)
+        } else if let Some(mut state) = self.get_state(&block.state_root(), Some(block.slot()))? {
+            let cache_hit = false;
+            f(&mut state, cache_hit).map(Some)
+        } else {
+            Ok(None)
+        }
+    }
+
     /// Return the sync committee at `slot + 1` from the canonical chain.
     ///
     /// This is useful when dealing with sync committee messages, because messages are signed
@@ -2387,6 +2426,7 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
         self: &Arc<Self>,
         chain_segment: Vec<BlockWrapper<T::EthSpec>>,
         count_unrealized: CountUnrealized,
+        notify_execution_layer: NotifyExecutionLayer,
     ) -> ChainSegmentResult<T::EthSpec> {
         let mut imported_blocks = 0;
 
@@ -2455,6 +2495,7 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
                         signature_verified_block.block_root(),
                         signature_verified_block,
                         count_unrealized,
+                        notify_execution_layer,
                     )
                     .await
                 {
@@ -2543,6 +2584,7 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
         block_root: Hash256,
         unverified_block: B,
         count_unrealized: CountUnrealized,
+        notify_execution_layer: NotifyExecutionLayer,
     ) -> Result<Hash256, BlockError<T::EthSpec>> {
         // Start the Prometheus timer.
         let _full_timer = metrics::start_timer(&metrics::BLOCK_PROCESSING_TIMES);
@@ -2555,8 +2597,11 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
         // A small closure to group the verification and import errors.
         let chain = self.clone();
         let import_block = async move {
-            let execution_pending =
-                unverified_block.into_execution_pending_block(block_root, &chain)?;
+            let execution_pending = unverified_block.into_execution_pending_block(
+                block_root,
+                &chain,
+                notify_execution_layer,
+            )?;
             chain
                 .import_execution_pending_block(execution_pending, count_unrealized)
                 .await
@@ -2626,6 +2671,7 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
             confirmed_state_roots,
             payload_verification_handle,
             parent_eth1_finalization_data,
+            consensus_context,
         } = execution_pending_block;
 
         let PayloadVerificationOutcome {
@@ -2679,6 +2725,7 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
                         count_unrealized,
                         parent_block,
                         parent_eth1_finalization_data,
+                        consensus_context,
                     )
                 },
                 "payload_verification_handle",
@@ -2704,70 +2751,36 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
         count_unrealized: CountUnrealized,
         parent_block: SignedBlindedBeaconBlock<T::EthSpec>,
         parent_eth1_finalization_data: Eth1FinalizationData,
+        mut consensus_context: ConsensusContext<T::EthSpec>,
     ) -> Result<Hash256, BlockError<T::EthSpec>> {
+        // ----------------------------- BLOCK NOT YET ATTESTABLE ----------------------------------
+        // Everything in this initial section is on the hot path between processing the block and
+        // being able to attest to it. DO NOT add any extra processing in this initial section
+        // unless it must run before fork choice.
+        // -----------------------------------------------------------------------------------------
         let current_slot = self.slot()?;
         let current_epoch = current_slot.epoch(T::EthSpec::slots_per_epoch());
+        let block = signed_block.message();
+        let post_exec_timer = metrics::start_timer(&metrics::BLOCK_PROCESSING_POST_EXEC_PROCESSING);
 
-        let attestation_observation_timer =
-            metrics::start_timer(&metrics::BLOCK_PROCESSING_ATTESTATION_OBSERVATION);
-
-        // Iterate through the attestations in the block and register them as an "observed
-        // attestation". This will stop us from propagating them on the gossip network.
-        for a in signed_block.message().body().attestations() {
-            match self.observed_attestations.write().observe_item(a, None) {
-                // If the observation was successful or if the slot for the attestation was too
-                // low, continue.
-                //
-                // We ignore `SlotTooLow` since this will be very common whilst syncing.
-                Ok(_) | Err(AttestationObservationError::SlotTooLow { .. }) => {}
-                Err(e) => return Err(BlockError::BeaconChainError(e.into())),
-            }
-        }
-
-        metrics::stop_timer(attestation_observation_timer);
-
-        // If a slasher is configured, provide the attestations from the block.
-        if let Some(slasher) = self.slasher.as_ref() {
-            for attestation in signed_block.message().body().attestations() {
-                let committee =
-                    state.get_beacon_committee(attestation.data.slot, attestation.data.index)?;
-                let indexed_attestation = get_indexed_attestation(committee.committee, attestation)
-                    .map_err(|e| BlockError::BeaconChainError(e.into()))?;
-                slasher.accept_attestation(indexed_attestation);
-            }
-        }
+        // Check against weak subjectivity checkpoint.
+        self.check_block_against_weak_subjectivity_checkpoint(block, block_root, &state)?;
 
         // If there are new validators in this block, update our pubkey cache.
         //
-        // We perform this _before_ adding the block to fork choice because the pubkey cache is
-        // used by attestation processing which will only process an attestation if the block is
-        // known to fork choice. This ordering ensure that the pubkey cache is always up-to-date.
-        self.validator_pubkey_cache
+        // The only keys imported here will be ones for validators deposited in this block, because
+        // the cache *must* already have been updated for the parent block when it was imported.
+        // Newly deposited validators are not active and their keys are not required by other parts
+        // of block processing. The reason we do this here and not after making the block attestable
+        // is so we don't have to think about lock ordering with respect to the fork choice lock.
+        // There are a bunch of places where we lock both fork choice and the pubkey cache and it
+        // would be difficult to check that they all lock fork choice first.
+        let mut kv_store_ops = self
+            .validator_pubkey_cache
             .try_write_for(VALIDATOR_PUBKEY_CACHE_LOCK_TIMEOUT)
             .ok_or(Error::ValidatorPubkeyCacheLockTimeout)?
             .import_new_pubkeys(&state)?;
 
-        // For the current and next epoch of this state, ensure we have the shuffling from this
-        // block in our cache.
-        for relative_epoch in &[RelativeEpoch::Current, RelativeEpoch::Next] {
-            let shuffling_id = AttestationShufflingId::new(block_root, &state, *relative_epoch)?;
-
-            let shuffling_is_cached = self
-                .shuffling_cache
-                .try_read_for(ATTESTATION_CACHE_LOCK_TIMEOUT)
-                .ok_or(Error::AttestationCacheLockTimeout)?
-                .contains(&shuffling_id);
-
-            if !shuffling_is_cached {
-                state.build_committee_cache(*relative_epoch, &self.spec)?;
-                let committee_cache = state.committee_cache(*relative_epoch)?;
-                self.shuffling_cache
-                    .try_write_for(ATTESTATION_CACHE_LOCK_TIMEOUT)
-                    .ok_or(Error::AttestationCacheLockTimeout)?
-                    .insert_committee_cache(shuffling_id, committee_cache);
-            }
-        }
-
         // Apply the state to the attester cache, only if it is from the previous epoch or later.
         //
         // In a perfect scenario there should be no need to add previous-epoch states to the cache.
@@ -2779,52 +2792,7 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
                 .map_err(BeaconChainError::from)?;
         }
 
-        // Alias for readability.
-        let block = signed_block.message();
-
-        // Only perform the weak subjectivity check if it was configured.
-        if let Some(wss_checkpoint) = self.config.weak_subjectivity_checkpoint {
-            // Note: we're using the finalized checkpoint from the head state, rather than fork
-            // choice.
-            //
-            // We are doing this to ensure that we detect changes in finalization. It's possible
-            // that fork choice has already been updated to the finalized checkpoint in the block
-            // we're importing.
-            let current_head_finalized_checkpoint =
-                self.canonical_head.cached_head().finalized_checkpoint();
-            // Compare the existing finalized checkpoint with the incoming block's finalized checkpoint.
-            let new_finalized_checkpoint = state.finalized_checkpoint();
-
-            // This ensures we only perform the check once.
-            if (current_head_finalized_checkpoint.epoch < wss_checkpoint.epoch)
-                && (wss_checkpoint.epoch <= new_finalized_checkpoint.epoch)
-            {
-                if let Err(e) =
-                    self.verify_weak_subjectivity_checkpoint(wss_checkpoint, block_root, &state)
-                {
-                    let mut shutdown_sender = self.shutdown_sender();
-                    crit!(
-                        self.log,
-                        "Weak subjectivity checkpoint verification failed while importing block!";
-                        "block_root" => ?block_root,
-                        "parent_root" => ?block.parent_root(),
-                        "old_finalized_epoch" => ?current_head_finalized_checkpoint.epoch,
-                        "new_finalized_epoch" => ?new_finalized_checkpoint.epoch,
-                        "weak_subjectivity_epoch" => ?wss_checkpoint.epoch,
-                        "error" => ?e,
-                    );
-                    crit!(self.log, "You must use the `--purge-db` flag to clear the database and restart sync. You may be on a hostile network.");
-                    shutdown_sender
-                        .try_send(ShutdownReason::Failure(
-                            "Weak subjectivity checkpoint verification failed. Provided block root is not a checkpoint."
-                        ))
-                        .map_err(|err| BlockError::BeaconChainError(BeaconChainError::WeakSubjectivtyShutdownError(err)))?;
-                    return Err(BlockError::WeakSubjectivityConflict);
-                }
-            }
-        }
-
-        // Take an exclusive write-lock on fork choice. It's very important prevent deadlocks by
+        // Take an exclusive write-lock on fork choice. It's very important to prevent deadlocks by
         // avoiding taking other locks whilst holding this lock.
         let mut fork_choice = self.canonical_head.fork_choice_write_lock();
 
@@ -2855,77 +2823,6 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
                 .map_err(|e| BlockError::BeaconChainError(e.into()))?;
         }
 
-        // Allow the validator monitor to learn about a new valid state.
-        self.validator_monitor
-            .write()
-            .process_valid_state(current_slot.epoch(T::EthSpec::slots_per_epoch()), &state);
-        let validator_monitor = self.validator_monitor.read();
-
-        // Register each attester slashing in the block with fork choice.
-        for attester_slashing in block.body().attester_slashings() {
-            fork_choice.on_attester_slashing(attester_slashing);
-        }
-
-        // Register each attestation in the block with the fork choice service.
-        for attestation in block.body().attestations() {
-            let _fork_choice_attestation_timer =
-                metrics::start_timer(&metrics::FORK_CHOICE_PROCESS_ATTESTATION_TIMES);
-            let attestation_target_epoch = attestation.data.target.epoch;
-
-            let committee =
-                state.get_beacon_committee(attestation.data.slot, attestation.data.index)?;
-            let indexed_attestation = get_indexed_attestation(committee.committee, attestation)
-                .map_err(|e| BlockError::BeaconChainError(e.into()))?;
-
-            match fork_choice.on_attestation(
-                current_slot,
-                &indexed_attestation,
-                AttestationFromBlock::True,
-                &self.spec,
-            ) {
-                Ok(()) => Ok(()),
-                // Ignore invalid attestations whilst importing attestations from a block. The
-                // block might be very old and therefore the attestations useless to fork choice.
-                Err(ForkChoiceError::InvalidAttestation(_)) => Ok(()),
-                Err(e) => Err(BlockError::BeaconChainError(e.into())),
-            }?;
-
-            // To avoid slowing down sync, only register attestations for the
-            // `observed_block_attesters` if they are from the previous epoch or later.
-            if attestation_target_epoch + 1 >= current_epoch {
-                let mut observed_block_attesters = self.observed_block_attesters.write();
-                for &validator_index in &indexed_attestation.attesting_indices {
-                    if let Err(e) = observed_block_attesters
-                        .observe_validator(attestation_target_epoch, validator_index as usize)
-                    {
-                        debug!(
-                            self.log,
-                            "Failed to register observed block attester";
-                            "error" => ?e,
-                            "epoch" => attestation_target_epoch,
-                            "validator_index" => validator_index,
-                        )
-                    }
-                }
-            }
-
-            // Only register this with the validator monitor when the block is sufficiently close to
-            // the current slot.
-            if VALIDATOR_MONITOR_HISTORIC_EPOCHS as u64 * T::EthSpec::slots_per_epoch()
-                + block.slot().as_u64()
-                >= current_slot.as_u64()
-            {
-                match fork_choice.get_block(&block.parent_root()) {
-                    Some(parent_block) => validator_monitor.register_attestation_in_block(
-                        &indexed_attestation,
-                        parent_block.slot,
-                        &self.spec,
-                    ),
-                    None => warn!(self.log, "Failed to get parent block"; "slot" => %block.slot()),
-                }
-            }
-        }
-
         // If the block is recent enough and it was not optimistically imported, check to see if it
         // becomes the head block. If so, apply it to the early attester cache. This will allow
         // attestations to the block without waiting for the block and state to be inserted to the
@@ -2974,56 +2871,28 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
                 ),
             }
         }
+        drop(post_exec_timer);
 
-        // Register sync aggregate with validator monitor
-        if let Ok(sync_aggregate) = block.body().sync_aggregate() {
-            // `SyncCommittee` for the sync_aggregate should correspond to the duty slot
-            let duty_epoch = block.slot().epoch(T::EthSpec::slots_per_epoch());
-            let sync_committee = self.sync_committee_at_epoch(duty_epoch)?;
-            let participant_pubkeys = sync_committee
-                .pubkeys
-                .iter()
-                .zip(sync_aggregate.sync_committee_bits.iter())
-                .filter_map(|(pubkey, bit)| bit.then_some(pubkey))
-                .collect::<Vec<_>>();
+        // ---------------------------- BLOCK PROBABLY ATTESTABLE ----------------------------------
+        // Most blocks are now capable of being attested to thanks to the `early_attester_cache`
+        // cache above. Resume non-essential processing.
+        // -----------------------------------------------------------------------------------------
 
-            validator_monitor.register_sync_aggregate_in_block(
-                block.slot(),
-                block.parent_root(),
-                participant_pubkeys,
-            );
-        }
-
-        for exit in block.body().voluntary_exits() {
-            validator_monitor.register_block_voluntary_exit(&exit.message)
-        }
-
-        for slashing in block.body().attester_slashings() {
-            validator_monitor.register_block_attester_slashing(slashing)
-        }
-
-        for slashing in block.body().proposer_slashings() {
-            validator_monitor.register_block_proposer_slashing(slashing)
-        }
-
-        drop(validator_monitor);
-
-        // Only present some metrics for blocks from the previous epoch or later.
-        //
-        // This helps avoid noise in the metrics during sync.
-        if block.slot().epoch(T::EthSpec::slots_per_epoch()) + 1 >= self.epoch()? {
-            metrics::observe(
-                &metrics::OPERATIONS_PER_BLOCK_ATTESTATION,
-                block.body().attestations().len() as f64,
-            );
-
-            if let Ok(sync_aggregate) = block.body().sync_aggregate() {
-                metrics::set_gauge(
-                    &metrics::BLOCK_SYNC_AGGREGATE_SET_BITS,
-                    sync_aggregate.num_set_bits() as i64,
-                );
-            }
-        }
+        self.import_block_update_shuffling_cache(block_root, &mut state)?;
+        self.import_block_observe_attestations(
+            block,
+            &state,
+            &mut consensus_context,
+            current_epoch,
+        );
+        self.import_block_update_validator_monitor(
+            block,
+            &state,
+            &mut consensus_context,
+            current_slot,
+            parent_block.slot(),
+        );
+        self.import_block_update_slasher(block, &state, &mut consensus_context);
 
         let db_write_timer = metrics::start_timer(&metrics::BLOCK_PROCESSING_DB_WRITE);
 
@@ -3046,7 +2915,9 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
         };
         let txn_lock = self.store.hot_db.begin_rw_transaction();
 
-        if let Err(e) = self.store.do_atomically(ops) {
+        kv_store_ops.extend(self.store.convert_to_kv_batch(ops)?);
+
+        if let Err(e) = self.store.hot_db.do_atomically(kv_store_ops) {
             error!(
                 self.log,
                 "Database write failed!";
@@ -3054,6 +2925,10 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
                 "error" => ?e,
             );
 
+            // Clear the early attester cache to prevent attestations which we would later be unable
+            // to verify due to the failure.
+            self.early_attester_cache.clear();
+
             // Since the write failed, try to revert the canonical head back to what was stored
             // in the database. This attempts to prevent inconsistency between the database and
             // fork choice.
@@ -3096,6 +2971,7 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
             eth1_deposit_index: state.eth1_deposit_index(),
         };
         let current_finalized_checkpoint = state.finalized_checkpoint();
+
         self.snapshot_cache
             .try_write_for(BLOCK_PROCESSING_CACHE_LOCK_TIMEOUT)
             .ok_or(Error::SnapshotCacheLockTimeout)
@@ -3103,7 +2979,7 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
                 snapshot_cache.insert(
                     BeaconSnapshot {
                         beacon_state: state,
-                        beacon_block: signed_block,
+                        beacon_block: signed_block.clone(),
                         beacon_block_root: block_root,
                     },
                     None,
@@ -3122,22 +2998,312 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
         self.head_tracker
             .register_block(block_root, parent_root, slot);
 
-        // Send an event to the `events` endpoint after fully processing the block.
-        if let Some(event_handler) = self.event_handler.as_ref() {
-            if event_handler.has_block_subscribers() {
-                event_handler.register(EventKind::Block(SseBlock {
-                    slot,
-                    block: block_root,
-                    execution_optimistic: payload_verification_status.is_optimistic(),
-                }));
-            }
-        }
-
         metrics::stop_timer(db_write_timer);
 
         metrics::inc_counter(&metrics::BLOCK_PROCESSING_SUCCESSES);
 
-        let block_delay_total = get_slot_delay_ms(block_time_imported, slot, &self.slot_clock);
+        // Update the deposit contract cache.
+        self.import_block_update_deposit_contract_finalization(
+            block,
+            block_root,
+            current_epoch,
+            current_finalized_checkpoint,
+            current_eth1_finalization_data,
+            parent_eth1_finalization_data,
+            parent_block.slot(),
+        );
+
+        // Inform the unknown block cache, in case it was waiting on this block.
+        self.pre_finalization_block_cache
+            .block_processed(block_root);
+
+        self.import_block_update_metrics_and_events(
+            block,
+            block_root,
+            block_time_imported,
+            payload_verification_status,
+            current_slot,
+        );
+
+        Ok(block_root)
+    }
+
+    /// Check block's consistentency with any configured weak subjectivity checkpoint.
+    fn check_block_against_weak_subjectivity_checkpoint(
+        &self,
+        block: BeaconBlockRef<T::EthSpec>,
+        block_root: Hash256,
+        state: &BeaconState<T::EthSpec>,
+    ) -> Result<(), BlockError<T::EthSpec>> {
+        // Only perform the weak subjectivity check if it was configured.
+        let wss_checkpoint = if let Some(checkpoint) = self.config.weak_subjectivity_checkpoint {
+            checkpoint
+        } else {
+            return Ok(());
+        };
+        // Note: we're using the finalized checkpoint from the head state, rather than fork
+        // choice.
+        //
+        // We are doing this to ensure that we detect changes in finalization. It's possible
+        // that fork choice has already been updated to the finalized checkpoint in the block
+        // we're importing.
+        let current_head_finalized_checkpoint =
+            self.canonical_head.cached_head().finalized_checkpoint();
+        // Compare the existing finalized checkpoint with the incoming block's finalized checkpoint.
+        let new_finalized_checkpoint = state.finalized_checkpoint();
+
+        // This ensures we only perform the check once.
+        if current_head_finalized_checkpoint.epoch < wss_checkpoint.epoch
+            && wss_checkpoint.epoch <= new_finalized_checkpoint.epoch
+        {
+            if let Err(e) =
+                self.verify_weak_subjectivity_checkpoint(wss_checkpoint, block_root, state)
+            {
+                let mut shutdown_sender = self.shutdown_sender();
+                crit!(
+                    self.log,
+                    "Weak subjectivity checkpoint verification failed while importing block!";
+                    "block_root" => ?block_root,
+                    "parent_root" => ?block.parent_root(),
+                    "old_finalized_epoch" => ?current_head_finalized_checkpoint.epoch,
+                    "new_finalized_epoch" => ?new_finalized_checkpoint.epoch,
+                    "weak_subjectivity_epoch" => ?wss_checkpoint.epoch,
+                    "error" => ?e
+                );
+                crit!(
+                    self.log,
+                    "You must use the `--purge-db` flag to clear the database and restart sync. \
+                         You may be on a hostile network."
+                );
+                shutdown_sender
+                    .try_send(ShutdownReason::Failure(
+                        "Weak subjectivity checkpoint verification failed. \
+                             Provided block root is not a checkpoint.",
+                    ))
+                    .map_err(|err| {
+                        BlockError::BeaconChainError(
+                            BeaconChainError::WeakSubjectivtyShutdownError(err),
+                        )
+                    })?;
+                return Err(BlockError::WeakSubjectivityConflict);
+            }
+        }
+        Ok(())
+    }
+
+    /// Process a block for the validator monitor, including all its constituent messages.
+    fn import_block_update_validator_monitor(
+        &self,
+        block: BeaconBlockRef<T::EthSpec>,
+        state: &BeaconState<T::EthSpec>,
+        ctxt: &mut ConsensusContext<T::EthSpec>,
+        current_slot: Slot,
+        parent_block_slot: Slot,
+    ) {
+        // Only register blocks with the validator monitor when the block is sufficiently close to
+        // the current slot.
+        if VALIDATOR_MONITOR_HISTORIC_EPOCHS as u64 * T::EthSpec::slots_per_epoch()
+            + block.slot().as_u64()
+            < current_slot.as_u64()
+        {
+            return;
+        }
+
+        // Allow the validator monitor to learn about a new valid state.
+        self.validator_monitor
+            .write()
+            .process_valid_state(current_slot.epoch(T::EthSpec::slots_per_epoch()), state);
+
+        let validator_monitor = self.validator_monitor.read();
+
+        // Sync aggregate.
+        if let Ok(sync_aggregate) = block.body().sync_aggregate() {
+            // `SyncCommittee` for the sync_aggregate should correspond to the duty slot
+            let duty_epoch = block.slot().epoch(T::EthSpec::slots_per_epoch());
+
+            match self.sync_committee_at_epoch(duty_epoch) {
+                Ok(sync_committee) => {
+                    let participant_pubkeys = sync_committee
+                        .pubkeys
+                        .iter()
+                        .zip(sync_aggregate.sync_committee_bits.iter())
+                        .filter_map(|(pubkey, bit)| bit.then_some(pubkey))
+                        .collect::<Vec<_>>();
+
+                    validator_monitor.register_sync_aggregate_in_block(
+                        block.slot(),
+                        block.parent_root(),
+                        participant_pubkeys,
+                    );
+                }
+                Err(e) => {
+                    warn!(
+                        self.log,
+                        "Unable to fetch sync committee";
+                        "epoch" => duty_epoch,
+                        "purpose" => "validator monitor",
+                        "error" => ?e,
+                    );
+                }
+            }
+        }
+
+        // Attestations.
+        for attestation in block.body().attestations() {
+            let indexed_attestation = match ctxt.get_indexed_attestation(state, attestation) {
+                Ok(indexed) => indexed,
+                Err(e) => {
+                    debug!(
+                        self.log,
+                        "Failed to get indexed attestation";
+                        "purpose" => "validator monitor",
+                        "attestation_slot" => attestation.data.slot,
+                        "error" => ?e,
+                    );
+                    continue;
+                }
+            };
+            validator_monitor.register_attestation_in_block(
+                indexed_attestation,
+                parent_block_slot,
+                &self.spec,
+            );
+        }
+
+        for exit in block.body().voluntary_exits() {
+            validator_monitor.register_block_voluntary_exit(&exit.message)
+        }
+
+        for slashing in block.body().attester_slashings() {
+            validator_monitor.register_block_attester_slashing(slashing)
+        }
+
+        for slashing in block.body().proposer_slashings() {
+            validator_monitor.register_block_proposer_slashing(slashing)
+        }
+    }
+
+    /// Iterate through the attestations in the block and register them as "observed".
+    ///
+    /// This will stop us from propagating them on the gossip network.
+    fn import_block_observe_attestations(
+        &self,
+        block: BeaconBlockRef<T::EthSpec>,
+        state: &BeaconState<T::EthSpec>,
+        ctxt: &mut ConsensusContext<T::EthSpec>,
+        current_epoch: Epoch,
+    ) {
+        // To avoid slowing down sync, only observe attestations if the block is from the
+        // previous epoch or later.
+        if state.current_epoch() + 1 < current_epoch {
+            return;
+        }
+
+        let _timer = metrics::start_timer(&metrics::BLOCK_PROCESSING_ATTESTATION_OBSERVATION);
+
+        for a in block.body().attestations() {
+            match self.observed_attestations.write().observe_item(a, None) {
+                // If the observation was successful or if the slot for the attestation was too
+                // low, continue.
+                //
+                // We ignore `SlotTooLow` since this will be very common whilst syncing.
+                Ok(_) | Err(AttestationObservationError::SlotTooLow { .. }) => {}
+                Err(e) => {
+                    debug!(
+                        self.log,
+                        "Failed to register observed attestation";
+                        "error" => ?e,
+                        "epoch" => a.data.target.epoch
+                    );
+                }
+            }
+
+            let indexed_attestation = match ctxt.get_indexed_attestation(state, a) {
+                Ok(indexed) => indexed,
+                Err(e) => {
+                    debug!(
+                        self.log,
+                        "Failed to get indexed attestation";
+                        "purpose" => "observation",
+                        "attestation_slot" => a.data.slot,
+                        "error" => ?e,
+                    );
+                    continue;
+                }
+            };
+
+            let mut observed_block_attesters = self.observed_block_attesters.write();
+
+            for &validator_index in &indexed_attestation.attesting_indices {
+                if let Err(e) = observed_block_attesters
+                    .observe_validator(a.data.target.epoch, validator_index as usize)
+                {
+                    debug!(
+                        self.log,
+                        "Failed to register observed block attester";
+                        "error" => ?e,
+                        "epoch" => a.data.target.epoch,
+                        "validator_index" => validator_index,
+                    )
+                }
+            }
+        }
+    }
+
+    /// If a slasher is configured, provide the attestations from the block.
+    fn import_block_update_slasher(
+        &self,
+        block: BeaconBlockRef<T::EthSpec>,
+        state: &BeaconState<T::EthSpec>,
+        ctxt: &mut ConsensusContext<T::EthSpec>,
+    ) {
+        if let Some(slasher) = self.slasher.as_ref() {
+            for attestation in block.body().attestations() {
+                let indexed_attestation = match ctxt.get_indexed_attestation(state, attestation) {
+                    Ok(indexed) => indexed,
+                    Err(e) => {
+                        debug!(
+                            self.log,
+                            "Failed to get indexed attestation";
+                            "purpose" => "slasher",
+                            "attestation_slot" => attestation.data.slot,
+                            "error" => ?e,
+                        );
+                        continue;
+                    }
+                };
+                slasher.accept_attestation(indexed_attestation.clone());
+            }
+        }
+    }
+
+    fn import_block_update_metrics_and_events(
+        &self,
+        block: BeaconBlockRef<T::EthSpec>,
+        block_root: Hash256,
+        block_time_imported: Duration,
+        payload_verification_status: PayloadVerificationStatus,
+        current_slot: Slot,
+    ) {
+        // Only present some metrics for blocks from the previous epoch or later.
+        //
+        // This helps avoid noise in the metrics during sync.
+        if block.slot() + 2 * T::EthSpec::slots_per_epoch() >= current_slot {
+            metrics::observe(
+                &metrics::OPERATIONS_PER_BLOCK_ATTESTATION,
+                block.body().attestations().len() as f64,
+            );
+
+            if let Ok(sync_aggregate) = block.body().sync_aggregate() {
+                metrics::set_gauge(
+                    &metrics::BLOCK_SYNC_AGGREGATE_SET_BITS,
+                    sync_aggregate.num_set_bits() as i64,
+                );
+            }
+        }
+
+        let block_delay_total =
+            get_slot_delay_ms(block_time_imported, block.slot(), &self.slot_clock);
 
         // Do not write to the cache for blocks older than 2 epochs, this helps reduce writes to
         // the cache during sync.
@@ -3169,62 +3335,105 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
             );
         }
 
-        // Do not write to eth1 finalization cache for blocks older than 5 epochs
-        // this helps reduce noise during sync
-        if block_delay_total
-            < self.slot_clock.slot_duration() * 5 * (T::EthSpec::slots_per_epoch() as u32)
-        {
-            let parent_block_epoch = parent_block.slot().epoch(T::EthSpec::slots_per_epoch());
-            if parent_block_epoch < current_epoch {
-                // we've crossed epoch boundary, store Eth1FinalizationData
-                let (checkpoint, eth1_finalization_data) =
-                    if current_slot % T::EthSpec::slots_per_epoch() == 0 {
-                        // current block is the checkpoint
-                        (
-                            Checkpoint {
-                                epoch: current_epoch,
-                                root: block_root,
-                            },
-                            current_eth1_finalization_data,
-                        )
-                    } else {
-                        // parent block is the checkpoint
-                        (
-                            Checkpoint {
-                                epoch: current_epoch,
-                                root: parent_block.canonical_root(),
-                            },
-                            parent_eth1_finalization_data,
-                        )
-                    };
+        if let Some(event_handler) = self.event_handler.as_ref() {
+            if event_handler.has_block_subscribers() {
+                event_handler.register(EventKind::Block(SseBlock {
+                    slot: block.slot(),
+                    block: block_root,
+                    execution_optimistic: payload_verification_status.is_optimistic(),
+                }));
+            }
+        }
+    }
 
-                if let Some(finalized_eth1_data) = self
-                    .eth1_finalization_cache
-                    .try_write_for(ETH1_FINALIZATION_CACHE_LOCK_TIMEOUT)
-                    .and_then(|mut cache| {
-                        cache.insert(checkpoint, eth1_finalization_data);
-                        cache.finalize(&current_finalized_checkpoint)
-                    })
-                {
-                    if let Some(eth1_chain) = self.eth1_chain.as_ref() {
-                        let finalized_deposit_count = finalized_eth1_data.deposit_count;
-                        eth1_chain.finalize_eth1_data(finalized_eth1_data);
-                        debug!(
-                            self.log,
-                            "called eth1_chain.finalize_eth1_data()";
-                            "epoch" => current_finalized_checkpoint.epoch,
-                            "deposit count" => finalized_deposit_count,
-                        );
-                    }
+    fn import_block_update_shuffling_cache(
+        &self,
+        block_root: Hash256,
+        state: &mut BeaconState<T::EthSpec>,
+    ) -> Result<(), BlockError<T::EthSpec>> {
+        // For the current and next epoch of this state, ensure we have the shuffling from this
+        // block in our cache.
+        for relative_epoch in [RelativeEpoch::Current, RelativeEpoch::Next] {
+            let shuffling_id = AttestationShufflingId::new(block_root, state, relative_epoch)?;
+
+            let shuffling_is_cached = self
+                .shuffling_cache
+                .try_read_for(ATTESTATION_CACHE_LOCK_TIMEOUT)
+                .ok_or(Error::AttestationCacheLockTimeout)?
+                .contains(&shuffling_id);
+
+            if !shuffling_is_cached {
+                state.build_committee_cache(relative_epoch, &self.spec)?;
+                let committee_cache = state.committee_cache(relative_epoch)?;
+                self.shuffling_cache
+                    .try_write_for(ATTESTATION_CACHE_LOCK_TIMEOUT)
+                    .ok_or(Error::AttestationCacheLockTimeout)?
+                    .insert_committee_cache(shuffling_id, committee_cache);
+            }
+        }
+        Ok(())
+    }
+
+    #[allow(clippy::too_many_arguments)]
+    fn import_block_update_deposit_contract_finalization(
+        &self,
+        block: BeaconBlockRef<T::EthSpec>,
+        block_root: Hash256,
+        current_epoch: Epoch,
+        current_finalized_checkpoint: Checkpoint,
+        current_eth1_finalization_data: Eth1FinalizationData,
+        parent_eth1_finalization_data: Eth1FinalizationData,
+        parent_block_slot: Slot,
+    ) {
+        // Do not write to eth1 finalization cache for blocks older than 5 epochs.
+        if block.slot().epoch(T::EthSpec::slots_per_epoch()) + 5 < current_epoch {
+            return;
+        }
+
+        let parent_block_epoch = parent_block_slot.epoch(T::EthSpec::slots_per_epoch());
+        if parent_block_epoch < current_epoch {
+            // we've crossed epoch boundary, store Eth1FinalizationData
+            let (checkpoint, eth1_finalization_data) =
+                if block.slot() % T::EthSpec::slots_per_epoch() == 0 {
+                    // current block is the checkpoint
+                    (
+                        Checkpoint {
+                            epoch: current_epoch,
+                            root: block_root,
+                        },
+                        current_eth1_finalization_data,
+                    )
+                } else {
+                    // parent block is the checkpoint
+                    (
+                        Checkpoint {
+                            epoch: current_epoch,
+                            root: block.parent_root(),
+                        },
+                        parent_eth1_finalization_data,
+                    )
+                };
+
+            if let Some(finalized_eth1_data) = self
+                .eth1_finalization_cache
+                .try_write_for(ETH1_FINALIZATION_CACHE_LOCK_TIMEOUT)
+                .and_then(|mut cache| {
+                    cache.insert(checkpoint, eth1_finalization_data);
+                    cache.finalize(&current_finalized_checkpoint)
+                })
+            {
+                if let Some(eth1_chain) = self.eth1_chain.as_ref() {
+                    let finalized_deposit_count = finalized_eth1_data.deposit_count;
+                    eth1_chain.finalize_eth1_data(finalized_eth1_data);
+                    debug!(
+                        self.log,
+                        "called eth1_chain.finalize_eth1_data()";
+                        "epoch" => current_finalized_checkpoint.epoch,
+                        "deposit count" => finalized_deposit_count,
+                    );
                 }
             }
         }
-
-        // Inform the unknown block cache, in case it was waiting on this block.
-        self.pre_finalization_block_cache
-            .block_processed(block_root);
-
-        Ok(block_root)
     }
 
     /// If configured, wait for the fork choice run at the start of the slot to complete.
@@ -3613,10 +3822,12 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
         // This will be a lot slower but guards against bugs in block production and can be
         // quickly rolled out without a release.
         if self.config.paranoid_block_proposal {
+            let mut tmp_ctxt = ConsensusContext::new(state.slot());
             attestations.retain(|att| {
                 verify_attestation_for_block_inclusion(
                     &state,
                     att,
+                    &mut tmp_ctxt,
                     VerifySignatures::True,
                     &self.spec,
                 )
@@ -4265,19 +4476,20 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
         .map(|withdrawals_opt| withdrawals_opt.map(|w| w.into()))
         .map_err(Error::PrepareProposerFailed)?;
 
-        let payload_attributes = PayloadAttributes::V2(PayloadAttributesV2 {
-            timestamp: self
-                .slot_clock
+        let payload_attributes = PayloadAttributes::new(
+            self.slot_clock
                 .start_of(prepare_slot)
                 .ok_or(Error::InvalidSlot(prepare_slot))?
                 .as_secs(),
-            prev_randao: head_random,
-            suggested_fee_recipient: execution_layer
+            head_random,
+            execution_layer
                 .get_suggested_fee_recipient(proposer as u64)
                 .await,
             #[cfg(feature = "withdrawals")]
             withdrawals,
-        });
+            #[cfg(not(feature = "withdrawals"))]
+            None,
+        );
 
         debug!(
             self.log,
diff --git a/beacon_node/beacon_chain/src/block_verification.rs b/beacon_node/beacon_chain/src/block_verification.rs
index 3396a3607..589c0656d 100644
--- a/beacon_node/beacon_chain/src/block_verification.rs
+++ b/beacon_node/beacon_chain/src/block_verification.rs
@@ -46,7 +46,7 @@ use crate::blob_verification::{validate_blob_for_gossip, BlobError};
 use crate::eth1_finalization_cache::Eth1FinalizationData;
 use crate::execution_payload::{
     is_optimistic_candidate_block, validate_execution_payload_for_gossip, validate_merge_block,
-    AllowOptimisticImport, PayloadNotifier,
+    AllowOptimisticImport, NotifyExecutionLayer, PayloadNotifier,
 };
 use crate::kzg_utils;
 use crate::snapshot_cache::PreProcessingSnapshot;
@@ -55,15 +55,15 @@ use crate::validator_pubkey_cache::ValidatorPubkeyCache;
 use crate::BlockError::BlobValidation;
 use crate::{
     beacon_chain::{
-        BeaconForkChoice, BLOCK_PROCESSING_CACHE_LOCK_TIMEOUT, MAXIMUM_GOSSIP_CLOCK_DISPARITY,
-        VALIDATOR_PUBKEY_CACHE_LOCK_TIMEOUT,
+        BeaconForkChoice, ForkChoiceError, BLOCK_PROCESSING_CACHE_LOCK_TIMEOUT,
+        MAXIMUM_GOSSIP_CLOCK_DISPARITY, VALIDATOR_PUBKEY_CACHE_LOCK_TIMEOUT,
     },
     metrics, BeaconChain, BeaconChainError, BeaconChainTypes,
 };
 use derivative::Derivative;
 use eth2::types::EventKind;
 use execution_layer::PayloadStatus;
-use fork_choice::PayloadVerificationStatus;
+use fork_choice::{AttestationFromBlock, PayloadVerificationStatus};
 use parking_lot::RwLockReadGuard;
 use proto_array::Block as ProtoBlock;
 use safe_arith::ArithError;
@@ -71,7 +71,7 @@ use slog::{debug, error, warn, Logger};
 use slot_clock::SlotClock;
 use ssz::Encode;
 use state_processing::per_block_processing::eip4844::eip4844::verify_kzg_commitments_against_transactions;
-use state_processing::per_block_processing::is_merge_transition_block;
+use state_processing::per_block_processing::{errors::IntoWithIndex, is_merge_transition_block};
 use state_processing::{
     block_signature_verifier::{BlockSignatureVerifier, Error as BlockSignatureVerifierError},
     per_block_processing, per_slot_processing,
@@ -576,8 +576,24 @@ pub fn signature_verify_chain_segment<T: BeaconChainTypes>(
     let pubkey_cache = get_validator_pubkey_cache(chain)?;
     let mut signature_verifier = get_signature_verifier(&state, &pubkey_cache, &chain.spec);
 
+    let mut signature_verified_blocks = Vec::with_capacity(chain_segment.len());
+
     for (block_root, block) in &chain_segment {
-        signature_verifier.include_all_signatures(block.block(), Some(*block_root), None)?;
+        let mut consensus_context = ConsensusContext::new(block.slot())
+            .set_current_block_root(*block_root)
+            //FIXME(sean) Consider removing this is we pass the blob wrapper everywhere
+            .set_blobs_sidecar(block.blobs_sidecar());
+
+        signature_verifier.include_all_signatures(block.block(), &mut consensus_context)?;
+
+        // Save the block and its consensus context. The context will have had its proposer index
+        // and attesting indices filled in, which can be used to accelerate later block processing.
+        signature_verified_blocks.push(SignatureVerifiedBlock {
+            block: block.clone(),
+            block_root: *block_root,
+            parent: None,
+            consensus_context,
+        });
     }
 
     if signature_verifier.verify().is_err() {
@@ -586,23 +602,6 @@ pub fn signature_verify_chain_segment<T: BeaconChainTypes>(
 
     drop(pubkey_cache);
 
-    let mut signature_verified_blocks = chain_segment
-        .into_iter()
-        .map(|(block_root, block)| {
-            // Proposer index has already been verified above during signature verification.
-            let consensus_context = ConsensusContext::new(block.slot())
-                .set_current_block_root(block_root)
-                .set_proposer_index(block.block().message().proposer_index())
-                .set_blobs_sidecar(block.blobs_sidecar());
-            SignatureVerifiedBlock {
-                block,
-                block_root,
-                parent: None,
-                consensus_context,
-            }
-        })
-        .collect::<Vec<_>>();
-
     if let Some(signature_verified_block) = signature_verified_blocks.first_mut() {
         signature_verified_block.parent = Some(parent);
     }
@@ -653,6 +652,7 @@ pub struct ExecutionPendingBlock<T: BeaconChainTypes> {
     pub parent_block: SignedBeaconBlock<T::EthSpec, BlindedPayload<T::EthSpec>>,
     pub parent_eth1_finalization_data: Eth1FinalizationData,
     pub confirmed_state_roots: Vec<Hash256>,
+    pub consensus_context: ConsensusContext<T::EthSpec>,
     pub payload_verification_handle: PayloadVerificationHandle<T::EthSpec>,
 }
 
@@ -664,8 +664,9 @@ pub trait IntoExecutionPendingBlock<T: BeaconChainTypes>: Sized {
         self,
         block_root: Hash256,
         chain: &Arc<BeaconChain<T>>,
+        notify_execution_layer: NotifyExecutionLayer,
     ) -> Result<ExecutionPendingBlock<T>, BlockError<T::EthSpec>> {
-        self.into_execution_pending_block_slashable(block_root, chain)
+        self.into_execution_pending_block_slashable(block_root, chain, notify_execution_layer)
             .map(|execution_pending| {
                 // Supply valid block to slasher.
                 if let Some(slasher) = chain.slasher.as_ref() {
@@ -682,6 +683,7 @@ pub trait IntoExecutionPendingBlock<T: BeaconChainTypes>: Sized {
         self,
         block_root: Hash256,
         chain: &Arc<BeaconChain<T>>,
+        notify_execution_layer: NotifyExecutionLayer,
     ) -> Result<ExecutionPendingBlock<T>, BlockSlashInfo<BlockError<T::EthSpec>>>;
 
     fn block(&self) -> &SignedBeaconBlock<T::EthSpec>;
@@ -956,10 +958,15 @@ impl<T: BeaconChainTypes> IntoExecutionPendingBlock<T> for GossipVerifiedBlock<T
         self,
         block_root: Hash256,
         chain: &Arc<BeaconChain<T>>,
+        notify_execution_layer: NotifyExecutionLayer,
     ) -> Result<ExecutionPendingBlock<T>, BlockSlashInfo<BlockError<T::EthSpec>>> {
         let execution_pending =
             SignatureVerifiedBlock::from_gossip_verified_block_check_slashable(self, chain)?;
-        execution_pending.into_execution_pending_block_slashable(block_root, chain)
+        execution_pending.into_execution_pending_block_slashable(
+            block_root,
+            chain,
+            notify_execution_layer,
+        )
     }
 
     fn block(&self) -> &SignedBeaconBlock<T::EthSpec> {
@@ -1002,14 +1009,15 @@ impl<T: BeaconChainTypes> SignatureVerifiedBlock<T> {
 
         let mut signature_verifier = get_signature_verifier(&state, &pubkey_cache, &chain.spec);
 
-        signature_verifier.include_all_signatures(block.block(), Some(block_root), None)?;
+        let mut consensus_context = ConsensusContext::new(block.slot())
+            .set_current_block_root(block_root)
+            .set_blobs_sidecar(block.blobs_sidecar());
+
+        signature_verifier.include_all_signatures(block.block(), &mut consensus_context)?;
 
         if signature_verifier.verify().is_ok() {
             Ok(Self {
-                consensus_context: ConsensusContext::new(block.slot())
-                    .set_current_block_root(block_root)
-                    .set_proposer_index(block.message().proposer_index())
-                    .set_blobs_sidecar(block.blobs_sidecar()),
+                consensus_context,
                 block,
                 block_root,
                 parent: Some(parent),
@@ -1054,16 +1062,16 @@ impl<T: BeaconChainTypes> SignatureVerifiedBlock<T> {
 
         // Gossip verification has already checked the proposer index. Use it to check the RANDAO
         // signature.
-        let verified_proposer_index = Some(block.message().proposer_index());
+        let mut consensus_context = from.consensus_context;
         signature_verifier
-            .include_all_signatures_except_proposal(block.block(), verified_proposer_index)?;
+            .include_all_signatures_except_proposal(block.block(), &mut consensus_context)?;
 
         if signature_verifier.verify().is_ok() {
             Ok(Self {
                 block,
                 block_root: from.block_root,
                 parent: Some(parent),
-                consensus_context: from.consensus_context,
+                consensus_context,
             })
         } else {
             Err(BlockError::InvalidSignature)
@@ -1091,6 +1099,7 @@ impl<T: BeaconChainTypes> IntoExecutionPendingBlock<T> for SignatureVerifiedBloc
         self,
         block_root: Hash256,
         chain: &Arc<BeaconChain<T>>,
+        notify_execution_layer: NotifyExecutionLayer,
     ) -> Result<ExecutionPendingBlock<T>, BlockSlashInfo<BlockError<T::EthSpec>>> {
         let header = self.block.block().signed_block_header();
         let (parent, block) = if let Some(parent) = self.parent {
@@ -1106,6 +1115,7 @@ impl<T: BeaconChainTypes> IntoExecutionPendingBlock<T> for SignatureVerifiedBloc
             parent,
             self.consensus_context,
             chain,
+            notify_execution_layer,
         )
         .map_err(|e| BlockSlashInfo::SignatureValid(header, e))
     }
@@ -1122,6 +1132,7 @@ impl<T: BeaconChainTypes> IntoExecutionPendingBlock<T> for Arc<SignedBeaconBlock
         self,
         block_root: Hash256,
         chain: &Arc<BeaconChain<T>>,
+        notify_execution_layer: NotifyExecutionLayer,
     ) -> Result<ExecutionPendingBlock<T>, BlockSlashInfo<BlockError<T::EthSpec>>> {
         // Perform an early check to prevent wasting time on irrelevant blocks.
         let block_root = check_block_relevancy(&self, block_root, chain)
@@ -1132,7 +1143,7 @@ impl<T: BeaconChainTypes> IntoExecutionPendingBlock<T> for Arc<SignedBeaconBlock
             block_root,
             chain,
         )?
-        .into_execution_pending_block_slashable(block_root, chain)
+        .into_execution_pending_block_slashable(block_root, chain, notify_execution_layer)
     }
 
     fn block(&self) -> &SignedBeaconBlock<T::EthSpec> {
@@ -1147,6 +1158,7 @@ impl<T: BeaconChainTypes> IntoExecutionPendingBlock<T> for BlockWrapper<T::EthSp
         self,
         block_root: Hash256,
         chain: &Arc<BeaconChain<T>>,
+        notify_execution_layer: NotifyExecutionLayer,
     ) -> Result<ExecutionPendingBlock<T>, BlockSlashInfo<BlockError<T::EthSpec>>> {
         // Perform an early check to prevent wasting time on irrelevant blocks.
         let block_root = check_block_relevancy(self.block(), block_root, chain).map_err(|e| {
@@ -1154,7 +1166,7 @@ impl<T: BeaconChainTypes> IntoExecutionPendingBlock<T> for BlockWrapper<T::EthSp
         })?;
 
         SignatureVerifiedBlock::check_slashable(self, block_root, chain)?
-            .into_execution_pending_block_slashable(block_root, chain)
+            .into_execution_pending_block_slashable(block_root, chain, notify_execution_layer)
     }
 
     fn block(&self) -> &SignedBeaconBlock<T::EthSpec> {
@@ -1176,6 +1188,7 @@ impl<T: BeaconChainTypes> ExecutionPendingBlock<T> {
         parent: PreProcessingSnapshot<T::EthSpec>,
         mut consensus_context: ConsensusContext<T::EthSpec>,
         chain: &Arc<BeaconChain<T>>,
+        notify_execution_layer: NotifyExecutionLayer,
     ) -> Result<Self, BlockError<T::EthSpec>> {
         if let Some(parent) = chain
             .canonical_head
@@ -1212,6 +1225,79 @@ impl<T: BeaconChainTypes> ExecutionPendingBlock<T> {
 
         check_block_relevancy(block.block(), block_root, chain)?;
 
+        // Define a future that will verify the execution payload with an execution engine.
+        //
+        // We do this as early as possible so that later parts of this function can run in parallel
+        // with the payload verification.
+        let payload_notifier = PayloadNotifier::new(
+            chain.clone(),
+            block.block_cloned(),
+            &parent.pre_state,
+            notify_execution_layer,
+        )?;
+        let is_valid_merge_transition_block =
+            is_merge_transition_block(&parent.pre_state, block.message().body());
+        let payload_verification_future = async move {
+            let chain = payload_notifier.chain.clone();
+            let block = payload_notifier.block.clone();
+
+            // If this block triggers the merge, check to ensure that it references valid execution
+            // blocks.
+            //
+            // The specification defines this check inside `on_block` in the fork-choice specification,
+            // however we perform the check here for two reasons:
+            //
+            // - There's no point in importing a block that will fail fork choice, so it's best to fail
+            //   early.
+            // - Doing the check here means we can keep our fork-choice implementation "pure". I.e., no
+            //   calls to remote servers.
+            if is_valid_merge_transition_block {
+                validate_merge_block(&chain, block.message(), AllowOptimisticImport::Yes).await?;
+            };
+
+            // The specification declares that this should be run *inside* `per_block_processing`,
+            // however we run it here to keep `per_block_processing` pure (i.e., no calls to external
+            // servers).
+            let payload_verification_status = payload_notifier.notify_new_payload().await?;
+
+            // If the payload did not validate or invalidate the block, check to see if this block is
+            // valid for optimistic import.
+            if payload_verification_status.is_optimistic() {
+                let block_hash_opt = block
+                    .message()
+                    .body()
+                    .execution_payload()
+                    .map(|full_payload| full_payload.block_hash());
+
+                // Ensure the block is a candidate for optimistic import.
+                if !is_optimistic_candidate_block(&chain, block.slot(), block.parent_root()).await?
+                {
+                    warn!(
+                        chain.log,
+                        "Rejecting optimistic block";
+                        "block_hash" => ?block_hash_opt,
+                        "msg" => "the execution engine is not synced"
+                    );
+                    return Err(ExecutionPayloadError::UnverifiedNonOptimisticCandidate.into());
+                }
+            }
+
+            Ok(PayloadVerificationOutcome {
+                payload_verification_status,
+                is_valid_merge_transition_block,
+            })
+        };
+        // Spawn the payload verification future as a new task, but don't wait for it to complete.
+        // The `payload_verification_future` will be awaited later to ensure verification completed
+        // successfully.
+        let payload_verification_handle = chain
+            .task_executor
+            .spawn_handle(
+                payload_verification_future,
+                "execution_payload_verification",
+            )
+            .ok_or(BeaconChainError::RuntimeShutdown)?;
+
         /*
          * Advance the given `parent.beacon_state` to the slot of the given `block`.
          */
@@ -1316,79 +1402,11 @@ impl<T: BeaconChainTypes> ExecutionPendingBlock<T> {
                 summaries.push(summary);
             }
         }
+        metrics::stop_timer(catchup_timer);
 
         let block_slot = block.slot();
         let state_current_epoch = state.current_epoch();
 
-        // Define a future that will verify the execution payload with an execution engine (but
-        // don't execute it yet).
-        let payload_notifier = PayloadNotifier::new(chain.clone(), block.block_cloned(), &state)?;
-        let is_valid_merge_transition_block =
-            is_merge_transition_block(&state, block.message().body());
-        let payload_verification_future = async move {
-            let chain = payload_notifier.chain.clone();
-            let block = payload_notifier.block.clone();
-
-            // If this block triggers the merge, check to ensure that it references valid execution
-            // blocks.
-            //
-            // The specification defines this check inside `on_block` in the fork-choice specification,
-            // however we perform the check here for two reasons:
-            //
-            // - There's no point in importing a block that will fail fork choice, so it's best to fail
-            //   early.
-            // - Doing the check here means we can keep our fork-choice implementation "pure". I.e., no
-            //   calls to remote servers.
-            if is_valid_merge_transition_block {
-                validate_merge_block(&chain, block.message(), AllowOptimisticImport::Yes).await?;
-            };
-
-            // The specification declares that this should be run *inside* `per_block_processing`,
-            // however we run it here to keep `per_block_processing` pure (i.e., no calls to external
-            // servers).
-            //
-            // It is important that this function is called *after* `per_slot_processing`, since the
-            // `randao` may change.
-            let payload_verification_status = payload_notifier.notify_new_payload().await?;
-
-            // If the payload did not validate or invalidate the block, check to see if this block is
-            // valid for optimistic import.
-            if payload_verification_status.is_optimistic() {
-                let block_hash_opt = block
-                    .message()
-                    .body()
-                    .execution_payload()
-                    .map(|full_payload| full_payload.block_hash());
-
-                // Ensure the block is a candidate for optimistic import.
-                if !is_optimistic_candidate_block(&chain, block.slot(), block.parent_root()).await?
-                {
-                    warn!(
-                        chain.log,
-                        "Rejecting optimistic block";
-                        "block_hash" => ?block_hash_opt,
-                        "msg" => "the execution engine is not synced"
-                    );
-                    return Err(ExecutionPayloadError::UnverifiedNonOptimisticCandidate.into());
-                }
-            }
-
-            Ok(PayloadVerificationOutcome {
-                payload_verification_status,
-                is_valid_merge_transition_block,
-            })
-        };
-        // Spawn the payload verification future as a new task, but don't wait for it to complete.
-        // The `payload_verification_future` will be awaited later to ensure verification completed
-        // successfully.
-        let payload_verification_handle = chain
-            .task_executor
-            .spawn_handle(
-                payload_verification_future,
-                "execution_payload_verification",
-            )
-            .ok_or(BeaconChainError::RuntimeShutdown)?;
-
         // If the block is sufficiently recent, notify the validator monitor.
         if let Some(slot) = chain.slot_clock.now() {
             let epoch = slot.epoch(T::EthSpec::slots_per_epoch());
@@ -1415,8 +1433,6 @@ impl<T: BeaconChainTypes> ExecutionPendingBlock<T> {
             }
         }
 
-        metrics::stop_timer(catchup_timer);
-
         /*
          * Build the committee caches on the state.
          */
@@ -1506,9 +1522,48 @@ impl<T: BeaconChainTypes> ExecutionPendingBlock<T> {
             });
         }
 
+        /*
+         * Apply the block's attestations to fork choice.
+         *
+         * We're running in parallel with the payload verification at this point, so this is
+         * free real estate.
+         */
+        let current_slot = chain.slot()?;
+        let mut fork_choice = chain.canonical_head.fork_choice_write_lock();
+
+        // Register each attester slashing in the block with fork choice.
+        for attester_slashing in block.message().body().attester_slashings() {
+            fork_choice.on_attester_slashing(attester_slashing);
+        }
+
+        // Register each attestation in the block with fork choice.
+        for (i, attestation) in block.message().body().attestations().iter().enumerate() {
+            let _fork_choice_attestation_timer =
+                metrics::start_timer(&metrics::FORK_CHOICE_PROCESS_ATTESTATION_TIMES);
+
+            let indexed_attestation = consensus_context
+                .get_indexed_attestation(&state, attestation)
+                .map_err(|e| BlockError::PerBlockProcessingError(e.into_with_index(i)))?;
+
+            match fork_choice.on_attestation(
+                current_slot,
+                indexed_attestation,
+                AttestationFromBlock::True,
+                &chain.spec,
+            ) {
+                Ok(()) => Ok(()),
+                // Ignore invalid attestations whilst importing attestations from a block. The
+                // block might be very old and therefore the attestations useless to fork choice.
+                Err(ForkChoiceError::InvalidAttestation(_)) => Ok(()),
+                Err(e) => Err(BlockError::BeaconChainError(e.into())),
+            }?;
+        }
+        drop(fork_choice);
+
         /*
          * Verify kzg proofs and kzg commitments against transactions if required
          */
+        //FIXME(sean) should this be prior to applying attestions to fork choice above? done in parallel?
         if let Some(ref sidecar) = consensus_context.blobs_sidecar() {
             if let Some(data_availability_boundary) = chain.data_availability_boundary() {
                 if block_slot.epoch(T::EthSpec::slots_per_epoch()) > data_availability_boundary {
@@ -1562,6 +1617,7 @@ impl<T: BeaconChainTypes> ExecutionPendingBlock<T> {
             parent_block: parent.beacon_block,
             parent_eth1_finalization_data,
             confirmed_state_roots,
+            consensus_context,
             payload_verification_handle,
         })
     }
diff --git a/beacon_node/beacon_chain/src/chain_config.rs b/beacon_node/beacon_chain/src/chain_config.rs
index 5e16a29cf..286cc17a9 100644
--- a/beacon_node/beacon_chain/src/chain_config.rs
+++ b/beacon_node/beacon_chain/src/chain_config.rs
@@ -45,6 +45,8 @@ pub struct ChainConfig {
     pub paranoid_block_proposal: bool,
     /// Whether to strictly count unrealized justified votes.
     pub count_unrealized_full: CountUnrealizedFull,
+    /// Optionally set timeout for calls to checkpoint sync endpoint.
+    pub checkpoint_sync_url_timeout: u64,
 }
 
 impl Default for ChainConfig {
@@ -65,6 +67,7 @@ impl Default for ChainConfig {
             always_reset_payload_statuses: false,
             paranoid_block_proposal: false,
             count_unrealized_full: CountUnrealizedFull::default(),
+            checkpoint_sync_url_timeout: 60,
         }
     }
 }
diff --git a/beacon_node/beacon_chain/src/execution_payload.rs b/beacon_node/beacon_chain/src/execution_payload.rs
index 85aedc659..1982bdbf0 100644
--- a/beacon_node/beacon_chain/src/execution_payload.rs
+++ b/beacon_node/beacon_chain/src/execution_payload.rs
@@ -12,7 +12,7 @@ use crate::{
     BeaconChain, BeaconChainError, BeaconChainTypes, BlockError, BlockProductionError,
     ExecutionPayloadError,
 };
-use execution_layer::{BlockProposalContents, BuilderParams, PayloadStatus};
+use execution_layer::{BlockProposalContents, BuilderParams, PayloadAttributes, PayloadStatus};
 use fork_choice::{InvalidationOperation, PayloadVerificationStatus};
 use proto_array::{Block as ProtoBlock, ExecutionStatus};
 use slog::debug;
@@ -38,6 +38,16 @@ pub enum AllowOptimisticImport {
     No,
 }
 
+/// Signal whether the execution payloads of new blocks should be
+/// immediately verified with the EL or imported optimistically without
+/// any EL communication.
+#[derive(Default, Clone, Copy)]
+pub enum NotifyExecutionLayer {
+    #[default]
+    Yes,
+    No,
+}
+
 /// Used to await the result of executing payload with a remote EE.
 pub struct PayloadNotifier<T: BeaconChainTypes> {
     pub chain: Arc<BeaconChain<T>>,
@@ -50,21 +60,28 @@ impl<T: BeaconChainTypes> PayloadNotifier<T> {
         chain: Arc<BeaconChain<T>>,
         block: Arc<SignedBeaconBlock<T::EthSpec>>,
         state: &BeaconState<T::EthSpec>,
+        notify_execution_layer: NotifyExecutionLayer,
     ) -> Result<Self, BlockError<T::EthSpec>> {
-        let payload_verification_status = if is_execution_enabled(state, block.message().body()) {
-            // Perform the initial stages of payload verification.
-            //
-            // We will duplicate these checks again during `per_block_processing`, however these checks
-            // are cheap and doing them here ensures we protect the execution engine from junk.
-            partially_verify_execution_payload::<T::EthSpec, FullPayload<T::EthSpec>>(
-                state,
-                block.message().execution_payload()?,
-                &chain.spec,
-            )
-            .map_err(BlockError::PerBlockProcessingError)?;
-            None
-        } else {
-            Some(PayloadVerificationStatus::Irrelevant)
+        let payload_verification_status = match notify_execution_layer {
+            NotifyExecutionLayer::No => Some(PayloadVerificationStatus::Optimistic),
+            NotifyExecutionLayer::Yes => {
+                if is_execution_enabled(state, block.message().body()) {
+                    // Perform the initial stages of payload verification.
+                    //
+                    // We will duplicate these checks again during `per_block_processing`, however these checks
+                    // are cheap and doing them here ensures we protect the execution engine from junk.
+                    partially_verify_execution_payload::<T::EthSpec, FullPayload<T::EthSpec>>(
+                        state,
+                        block.slot(),
+                        block.message().execution_payload()?,
+                        &chain.spec,
+                    )
+                    .map_err(BlockError::PerBlockProcessingError)?;
+                    None
+                } else {
+                    Some(PayloadVerificationStatus::Irrelevant)
+                }
+            }
         };
 
         Ok(Self {
@@ -360,7 +377,8 @@ pub fn get_execution_payload<
     let spec = &chain.spec;
     let current_epoch = state.current_epoch();
     let is_merge_transition_complete = is_merge_transition_complete(state);
-    let timestamp = compute_timestamp_at_slot(state, spec).map_err(BeaconStateError::from)?;
+    let timestamp =
+        compute_timestamp_at_slot(state, state.slot(), spec).map_err(BeaconStateError::from)?;
     let random = *state.get_randao_mix(current_epoch)?;
     let latest_execution_payload_header_block_hash =
         state.latest_execution_payload_header()?.block_hash();
@@ -483,20 +501,29 @@ where
         .await
         .map_err(BlockProductionError::BeaconChain)?;
 
+    let suggested_fee_recipient = execution_layer
+        .get_suggested_fee_recipient(proposer_index)
+        .await;
+    let payload_attributes = PayloadAttributes::new(
+        timestamp,
+        random,
+        suggested_fee_recipient,
+        #[cfg(feature = "withdrawals")]
+        withdrawals,
+        #[cfg(not(feature = "withdrawals"))]
+        None,
+    );
+
     // Note: the suggested_fee_recipient is stored in the `execution_layer`, it will add this parameter.
     //
     // This future is not executed here, it's up to the caller to await it.
     let block_contents = execution_layer
         .get_payload::<Payload>(
             parent_hash,
-            timestamp,
-            random,
-            proposer_index,
+            &payload_attributes,
             forkchoice_update_params,
             builder_params,
             fork,
-            #[cfg(feature = "withdrawals")]
-            withdrawals,
             &chain.spec,
         )
         .await
diff --git a/beacon_node/beacon_chain/src/lib.rs b/beacon_node/beacon_chain/src/lib.rs
index e1831078d..497aa76d5 100644
--- a/beacon_node/beacon_chain/src/lib.rs
+++ b/beacon_node/beacon_chain/src/lib.rs
@@ -66,6 +66,7 @@ pub use canonical_head::{CachedHead, CanonicalHead, CanonicalHeadRwLock};
 pub use eth1_chain::{Eth1Chain, Eth1ChainBackend};
 pub use events::ServerSentEventHandler;
 pub use execution_layer::EngineState;
+pub use execution_payload::NotifyExecutionLayer;
 pub use fork_choice::{ExecutionStatus, ForkchoiceUpdateParameters};
 pub use metrics::scrape_for_metrics;
 pub use parking_lot;
diff --git a/beacon_node/beacon_chain/src/metrics.rs b/beacon_node/beacon_chain/src/metrics.rs
index f8accec14..6eefc569f 100644
--- a/beacon_node/beacon_chain/src/metrics.rs
+++ b/beacon_node/beacon_chain/src/metrics.rs
@@ -64,6 +64,11 @@ lazy_static! {
         "beacon_block_processing_state_root_seconds",
         "Time spent calculating the state root when processing a block."
     );
+    pub static ref BLOCK_PROCESSING_POST_EXEC_PROCESSING: Result<Histogram> = try_create_histogram_with_buckets(
+        "beacon_block_processing_post_exec_pre_attestable_seconds",
+        "Time between finishing execution processing and the block becoming attestable",
+        linear_buckets(5e-3, 5e-3, 10)
+    );
     pub static ref BLOCK_PROCESSING_DB_WRITE: Result<Histogram> = try_create_histogram(
         "beacon_block_processing_db_write_seconds",
         "Time spent writing a newly processed block and state to DB"
diff --git a/beacon_node/beacon_chain/src/snapshot_cache.rs b/beacon_node/beacon_chain/src/snapshot_cache.rs
index 40b73451c..33447bc2e 100644
--- a/beacon_node/beacon_chain/src/snapshot_cache.rs
+++ b/beacon_node/beacon_chain/src/snapshot_cache.rs
@@ -298,6 +298,27 @@ impl<T: EthSpec> SnapshotCache<T> {
             })
     }
 
+    /// Borrow the state corresponding to `block_root` if it exists in the cache *unadvanced*.
+    ///
+    /// Care must be taken not to mutate the state in an invalid way. This function should only
+    /// be used to mutate the *caches* of the state, for example the tree hash cache when
+    /// calculating a light client merkle proof.
+    pub fn borrow_unadvanced_state_mut(
+        &mut self,
+        block_root: Hash256,
+    ) -> Option<&mut BeaconState<T>> {
+        self.snapshots
+            .iter_mut()
+            .find(|snapshot| {
+                // If the pre-state exists then state advance has already taken the state for
+                // `block_root` and mutated its tree hash cache. Rather than re-building it while
+                // holding the snapshot cache lock (>1 second), prefer to return `None` from this
+                // function and force the caller to load it from disk.
+                snapshot.beacon_block_root == block_root && snapshot.pre_state.is_none()
+            })
+            .map(|snapshot| &mut snapshot.beacon_state)
+    }
+
     /// If there is a snapshot with `block_root`, clone it and return the clone.
     pub fn get_cloned(
         &self,
diff --git a/beacon_node/beacon_chain/src/test_utils.rs b/beacon_node/beacon_chain/src/test_utils.rs
index a1c7acf17..b88966b41 100644
--- a/beacon_node/beacon_chain/src/test_utils.rs
+++ b/beacon_node/beacon_chain/src/test_utils.rs
@@ -2,7 +2,7 @@ pub use crate::persisted_beacon_chain::PersistedBeaconChain;
 pub use crate::{
     beacon_chain::{BEACON_CHAIN_DB_KEY, ETH1_CACHE_DB_KEY, FORK_CHOICE_DB_KEY, OP_POOL_DB_KEY},
     migrate::MigratorConfig,
-    BeaconChainError, ProduceBlockVerification,
+    BeaconChainError, NotifyExecutionLayer, ProduceBlockVerification,
 };
 use crate::{
     builder::{BeaconChainBuilder, Witness},
@@ -586,7 +586,7 @@ where
 
     pub fn get_timestamp_at_slot(&self) -> u64 {
         let state = self.get_current_state();
-        compute_timestamp_at_slot(&state, &self.spec).unwrap()
+        compute_timestamp_at_slot(&state, state.slot(), &self.spec).unwrap()
     }
 
     pub fn get_current_state_and_root(&self) -> (BeaconState<E>, Hash256) {
@@ -1460,7 +1460,12 @@ where
         self.set_current_slot(slot);
         let block_hash: SignedBeaconBlockHash = self
             .chain
-            .process_block(block_root, Arc::new(block), CountUnrealized::True)
+            .process_block(
+                block_root,
+                Arc::new(block),
+                CountUnrealized::True,
+                NotifyExecutionLayer::Yes,
+            )
             .await?
             .into();
         self.chain.recompute_head_at_current_slot().await;
@@ -1477,6 +1482,7 @@ where
                 block.canonical_root(),
                 Arc::new(block),
                 CountUnrealized::True,
+                NotifyExecutionLayer::Yes,
             )
             .await?
             .into();
diff --git a/beacon_node/beacon_chain/src/validator_monitor.rs b/beacon_node/beacon_chain/src/validator_monitor.rs
index 95f4aadce..f9203f74b 100644
--- a/beacon_node/beacon_chain/src/validator_monitor.rs
+++ b/beacon_node/beacon_chain/src/validator_monitor.rs
@@ -109,6 +109,11 @@ impl EpochSummary {
         }
     }
 
+    pub fn register_block(&mut self, delay: Duration) {
+        self.blocks += 1;
+        Self::update_if_lt(&mut self.block_min_delay, delay);
+    }
+
     pub fn register_unaggregated_attestation(&mut self, delay: Duration) {
         self.attestations += 1;
         Self::update_if_lt(&mut self.attestation_min_delay, delay);
@@ -613,13 +618,6 @@ impl<T: EthSpec> ValidatorMonitor<T> {
         Ok(())
     }
 
-    fn get_validator_id(&self, validator_index: u64) -> Option<&str> {
-        self.indices
-            .get(&validator_index)
-            .and_then(|pubkey| self.validators.get(pubkey))
-            .map(|validator| validator.id.as_str())
-    }
-
     fn get_validator(&self, validator_index: u64) -> Option<&MonitoredValidator> {
         self.indices
             .get(&validator_index)
@@ -685,7 +683,9 @@ impl<T: EthSpec> ValidatorMonitor<T> {
         block_root: Hash256,
         slot_clock: &S,
     ) {
-        if let Some(id) = self.get_validator_id(block.proposer_index()) {
+        let epoch = block.slot().epoch(T::slots_per_epoch());
+        if let Some(validator) = self.get_validator(block.proposer_index()) {
+            let id = &validator.id;
             let delay = get_block_delay_ms(seen_timestamp, block, slot_clock);
 
             metrics::inc_counter_vec(&metrics::VALIDATOR_MONITOR_BEACON_BLOCK_TOTAL, &[src, id]);
@@ -704,6 +704,8 @@ impl<T: EthSpec> ValidatorMonitor<T> {
                 "src" => src,
                 "validator" => %id,
             );
+
+            validator.with_epoch_summary(epoch, |summary| summary.register_block(delay));
         }
     }
 
diff --git a/beacon_node/beacon_chain/src/validator_pubkey_cache.rs b/beacon_node/beacon_chain/src/validator_pubkey_cache.rs
index 60fdb607c..26aea2d27 100644
--- a/beacon_node/beacon_chain/src/validator_pubkey_cache.rs
+++ b/beacon_node/beacon_chain/src/validator_pubkey_cache.rs
@@ -3,7 +3,8 @@ use crate::{BeaconChainTypes, BeaconStore};
 use ssz::{Decode, Encode};
 use std::collections::HashMap;
 use std::convert::TryInto;
-use store::{DBColumn, Error as StoreError, StoreItem};
+use std::marker::PhantomData;
+use store::{DBColumn, Error as StoreError, KeyValueStore, KeyValueStoreOp, StoreItem};
 use types::{BeaconState, Hash256, PublicKey, PublicKeyBytes};
 
 /// Provides a mapping of `validator_index -> validator_publickey`.
@@ -14,21 +15,17 @@ use types::{BeaconState, Hash256, PublicKey, PublicKeyBytes};
 /// 2. To reduce the amount of public key _decompression_ required. A `BeaconState` stores public
 ///    keys in compressed form and they are needed in decompressed form for signature verification.
 ///    Decompression is expensive when many keys are involved.
-///
-/// The cache has a `backing` that it uses to maintain a persistent, on-disk
-/// copy of itself. This allows it to be restored between process invocations.
 pub struct ValidatorPubkeyCache<T: BeaconChainTypes> {
     pubkeys: Vec<PublicKey>,
     indices: HashMap<PublicKeyBytes, usize>,
     pubkey_bytes: Vec<PublicKeyBytes>,
-    store: BeaconStore<T>,
+    _phantom: PhantomData<T>,
 }
 
 impl<T: BeaconChainTypes> ValidatorPubkeyCache<T> {
     /// Create a new public key cache using the keys in `state.validators`.
     ///
-    /// Also creates a new persistence file, returning an error if there is already a file at
-    /// `persistence_path`.
+    /// The new cache will be updated with the keys from `state` and immediately written to disk.
     pub fn new(
         state: &BeaconState<T::EthSpec>,
         store: BeaconStore<T>,
@@ -37,10 +34,11 @@ impl<T: BeaconChainTypes> ValidatorPubkeyCache<T> {
             pubkeys: vec![],
             indices: HashMap::new(),
             pubkey_bytes: vec![],
-            store,
+            _phantom: PhantomData,
         };
 
-        cache.import_new_pubkeys(state)?;
+        let store_ops = cache.import_new_pubkeys(state)?;
+        store.hot_db.do_atomically(store_ops)?;
 
         Ok(cache)
     }
@@ -69,17 +67,19 @@ impl<T: BeaconChainTypes> ValidatorPubkeyCache<T> {
             pubkeys,
             indices,
             pubkey_bytes,
-            store,
+            _phantom: PhantomData,
         })
     }
 
     /// Scan the given `state` and add any new validator public keys.
     ///
     /// Does not delete any keys from `self` if they don't appear in `state`.
+    ///
+    /// NOTE: The caller *must* commit the returned I/O batch as part of the block import process.
     pub fn import_new_pubkeys(
         &mut self,
         state: &BeaconState<T::EthSpec>,
-    ) -> Result<(), BeaconChainError> {
+    ) -> Result<Vec<KeyValueStoreOp>, BeaconChainError> {
         if state.validators().len() > self.pubkeys.len() {
             self.import(
                 state.validators()[self.pubkeys.len()..]
@@ -87,12 +87,12 @@ impl<T: BeaconChainTypes> ValidatorPubkeyCache<T> {
                     .map(|v| v.pubkey),
             )
         } else {
-            Ok(())
+            Ok(vec![])
         }
     }
 
     /// Adds zero or more validators to `self`.
-    fn import<I>(&mut self, validator_keys: I) -> Result<(), BeaconChainError>
+    fn import<I>(&mut self, validator_keys: I) -> Result<Vec<KeyValueStoreOp>, BeaconChainError>
     where
         I: Iterator<Item = PublicKeyBytes> + ExactSizeIterator,
     {
@@ -100,6 +100,7 @@ impl<T: BeaconChainTypes> ValidatorPubkeyCache<T> {
         self.pubkeys.reserve(validator_keys.len());
         self.indices.reserve(validator_keys.len());
 
+        let mut store_ops = Vec::with_capacity(validator_keys.len());
         for pubkey in validator_keys {
             let i = self.pubkeys.len();
 
@@ -107,17 +108,11 @@ impl<T: BeaconChainTypes> ValidatorPubkeyCache<T> {
                 return Err(BeaconChainError::DuplicateValidatorPublicKey);
             }
 
-            // The item is written to disk _before_ it is written into
-            // the local struct.
-            //
-            // This means that a pubkey cache read from disk will always be equivalent to or
-            // _later than_ the cache that was running in the previous instance of Lighthouse.
-            //
-            // The motivation behind this ordering is that we do not want to have states that
-            // reference a pubkey that is not in our cache. However, it's fine to have pubkeys
-            // that are never referenced in a state.
-            self.store
-                .put_item(&DatabasePubkey::key_for_index(i), &DatabasePubkey(pubkey))?;
+            // Stage the new validator key for writing to disk.
+            // It will be committed atomically when the block that introduced it is written to disk.
+            // Notably it is NOT written while the write lock on the cache is held.
+            // See: https://github.com/sigp/lighthouse/issues/2327
+            store_ops.push(DatabasePubkey(pubkey).as_kv_store_op(DatabasePubkey::key_for_index(i)));
 
             self.pubkeys.push(
                 (&pubkey)
@@ -129,7 +124,7 @@ impl<T: BeaconChainTypes> ValidatorPubkeyCache<T> {
             self.indices.insert(pubkey, i);
         }
 
-        Ok(())
+        Ok(store_ops)
     }
 
     /// Get the public key for a validator with index `i`.
@@ -296,9 +291,10 @@ mod test {
 
         // Add some more keypairs.
         let (state, keypairs) = get_state(12);
-        cache
+        let ops = cache
             .import_new_pubkeys(&state)
             .expect("should import pubkeys");
+        store.hot_db.do_atomically(ops).unwrap();
         check_cache_get(&cache, &keypairs[..]);
         drop(cache);
 
diff --git a/beacon_node/beacon_chain/tests/block_verification.rs b/beacon_node/beacon_chain/tests/block_verification.rs
index 998f22f77..38a55e221 100644
--- a/beacon_node/beacon_chain/tests/block_verification.rs
+++ b/beacon_node/beacon_chain/tests/block_verification.rs
@@ -3,7 +3,7 @@
 use beacon_chain::test_utils::{
     AttestationStrategy, BeaconChainHarness, BlockStrategy, EphemeralHarnessType,
 };
-use beacon_chain::{BeaconSnapshot, BlockError, ChainSegmentResult};
+use beacon_chain::{BeaconSnapshot, BlockError, ChainSegmentResult, NotifyExecutionLayer};
 use fork_choice::CountUnrealized;
 use lazy_static::lazy_static;
 use logging::test_logger;
@@ -147,14 +147,18 @@ async fn chain_segment_full_segment() {
     // Sneak in a little check to ensure we can process empty chain segments.
     harness
         .chain
-        .process_chain_segment(vec![], CountUnrealized::True)
+        .process_chain_segment(vec![], CountUnrealized::True, NotifyExecutionLayer::Yes)
         .await
         .into_block_error()
         .expect("should import empty chain segment");
 
     harness
         .chain
-        .process_chain_segment(blocks.clone(), CountUnrealized::True)
+        .process_chain_segment(
+            blocks.clone(),
+            CountUnrealized::True,
+            NotifyExecutionLayer::Yes,
+        )
         .await
         .into_block_error()
         .expect("should import chain segment");
@@ -183,7 +187,11 @@ async fn chain_segment_varying_chunk_size() {
         for chunk in blocks.chunks(*chunk_size) {
             harness
                 .chain
-                .process_chain_segment(chunk.to_vec(), CountUnrealized::True)
+                .process_chain_segment(
+                    chunk.to_vec(),
+                    CountUnrealized::True,
+                    NotifyExecutionLayer::Yes,
+                )
                 .await
                 .into_block_error()
                 .unwrap_or_else(|_| panic!("should import chain segment of len {}", chunk_size));
@@ -219,7 +227,7 @@ async fn chain_segment_non_linear_parent_roots() {
         matches!(
             harness
                 .chain
-                .process_chain_segment(blocks, CountUnrealized::True)
+                .process_chain_segment(blocks, CountUnrealized::True, NotifyExecutionLayer::Yes)
                 .await
                 .into_block_error(),
             Err(BlockError::NonLinearParentRoots)
@@ -239,7 +247,7 @@ async fn chain_segment_non_linear_parent_roots() {
         matches!(
             harness
                 .chain
-                .process_chain_segment(blocks, CountUnrealized::True)
+                .process_chain_segment(blocks, CountUnrealized::True, NotifyExecutionLayer::Yes)
                 .await
                 .into_block_error(),
             Err(BlockError::NonLinearParentRoots)
@@ -270,7 +278,7 @@ async fn chain_segment_non_linear_slots() {
         matches!(
             harness
                 .chain
-                .process_chain_segment(blocks, CountUnrealized::True)
+                .process_chain_segment(blocks, CountUnrealized::True, NotifyExecutionLayer::Yes)
                 .await
                 .into_block_error(),
             Err(BlockError::NonLinearSlots)
@@ -291,7 +299,7 @@ async fn chain_segment_non_linear_slots() {
         matches!(
             harness
                 .chain
-                .process_chain_segment(blocks, CountUnrealized::True)
+                .process_chain_segment(blocks, CountUnrealized::True, NotifyExecutionLayer::Yes)
                 .await
                 .into_block_error(),
             Err(BlockError::NonLinearSlots)
@@ -317,7 +325,7 @@ async fn assert_invalid_signature(
         matches!(
             harness
                 .chain
-                .process_chain_segment(blocks, CountUnrealized::True)
+                .process_chain_segment(blocks, CountUnrealized::True, NotifyExecutionLayer::Yes)
                 .await
                 .into_block_error(),
             Err(BlockError::InvalidSignature)
@@ -339,7 +347,11 @@ async fn assert_invalid_signature(
     // imported prior to this test.
     let _ = harness
         .chain
-        .process_chain_segment(ancestor_blocks, CountUnrealized::True)
+        .process_chain_segment(
+            ancestor_blocks,
+            CountUnrealized::True,
+            NotifyExecutionLayer::Yes,
+        )
         .await;
     harness.chain.recompute_head_at_current_slot().await;
 
@@ -349,6 +361,7 @@ async fn assert_invalid_signature(
             snapshots[block_index].beacon_block.canonical_root(),
             snapshots[block_index].beacon_block.clone(),
             CountUnrealized::True,
+            NotifyExecutionLayer::Yes,
         )
         .await;
     assert!(
@@ -400,7 +413,11 @@ async fn invalid_signature_gossip_block() {
             .collect();
         harness
             .chain
-            .process_chain_segment(ancestor_blocks, CountUnrealized::True)
+            .process_chain_segment(
+                ancestor_blocks,
+                CountUnrealized::True,
+                NotifyExecutionLayer::Yes,
+            )
             .await
             .into_block_error()
             .expect("should import all blocks prior to the one being tested");
@@ -412,7 +429,8 @@ async fn invalid_signature_gossip_block() {
                     .process_block(
                         signed_block.canonical_root(),
                         Arc::new(signed_block),
-                        CountUnrealized::True
+                        CountUnrealized::True,
+                        NotifyExecutionLayer::Yes,
                     )
                     .await,
                 Err(BlockError::InvalidSignature)
@@ -446,7 +464,7 @@ async fn invalid_signature_block_proposal() {
             matches!(
                 harness
                     .chain
-                    .process_chain_segment(blocks, CountUnrealized::True)
+                    .process_chain_segment(blocks, CountUnrealized::True, NotifyExecutionLayer::Yes)
                     .await
                     .into_block_error(),
                 Err(BlockError::InvalidSignature)
@@ -644,7 +662,7 @@ async fn invalid_signature_deposit() {
             !matches!(
                 harness
                     .chain
-                    .process_chain_segment(blocks, CountUnrealized::True)
+                    .process_chain_segment(blocks, CountUnrealized::True, NotifyExecutionLayer::Yes)
                     .await
                     .into_block_error(),
                 Err(BlockError::InvalidSignature)
@@ -725,6 +743,7 @@ async fn block_gossip_verification() {
                 gossip_verified.block_root,
                 gossip_verified,
                 CountUnrealized::True,
+                NotifyExecutionLayer::Yes,
             )
             .await
             .expect("should import valid gossip verified block");
@@ -996,6 +1015,7 @@ async fn verify_block_for_gossip_slashing_detection() {
             verified_block.block_root,
             verified_block,
             CountUnrealized::True,
+            NotifyExecutionLayer::Yes,
         )
         .await
         .unwrap();
@@ -1035,6 +1055,7 @@ async fn verify_block_for_gossip_doppelganger_detection() {
             verified_block.block_root,
             verified_block,
             CountUnrealized::True,
+            NotifyExecutionLayer::Yes,
         )
         .await
         .unwrap();
@@ -1180,7 +1201,8 @@ async fn add_base_block_to_altair_chain() {
             .process_block(
                 base_block.canonical_root(),
                 Arc::new(base_block.clone()),
-                CountUnrealized::True
+                CountUnrealized::True,
+                NotifyExecutionLayer::Yes,
             )
             .await
             .err()
@@ -1195,7 +1217,11 @@ async fn add_base_block_to_altair_chain() {
     assert!(matches!(
         harness
             .chain
-            .process_chain_segment(vec![Arc::new(base_block)], CountUnrealized::True)
+            .process_chain_segment(
+                vec![Arc::new(base_block)],
+                CountUnrealized::True,
+                NotifyExecutionLayer::Yes,
+            )
             .await,
         ChainSegmentResult::Failed {
             imported_blocks: 0,
@@ -1313,7 +1339,8 @@ async fn add_altair_block_to_base_chain() {
             .process_block(
                 altair_block.canonical_root(),
                 Arc::new(altair_block.clone()),
-                CountUnrealized::True
+                CountUnrealized::True,
+                NotifyExecutionLayer::Yes,
             )
             .await
             .err()
@@ -1328,7 +1355,11 @@ async fn add_altair_block_to_base_chain() {
     assert!(matches!(
         harness
             .chain
-            .process_chain_segment(vec![Arc::new(altair_block)], CountUnrealized::True)
+            .process_chain_segment(
+                vec![Arc::new(altair_block)],
+                CountUnrealized::True,
+                NotifyExecutionLayer::Yes
+            )
             .await,
         ChainSegmentResult::Failed {
             imported_blocks: 0,
diff --git a/beacon_node/beacon_chain/tests/merge.rs b/beacon_node/beacon_chain/tests/merge.rs
index 19e8902a3..ea4e7cb88 100644
--- a/beacon_node/beacon_chain/tests/merge.rs
+++ b/beacon_node/beacon_chain/tests/merge.rs
@@ -12,17 +12,17 @@ fn verify_execution_payload_chain<T: EthSpec>(chain: &[FullPayload<T>]) {
     let mut prev_ep: Option<FullPayload<T>> = None;
 
     for ep in chain {
-        assert!(*ep != FullPayload::default());
+        assert!(!ep.is_default_with_empty_roots());
         assert!(ep.block_hash() != ExecutionBlockHash::zero());
 
         // Check against previous `ExecutionPayload`.
         if let Some(prev_ep) = prev_ep {
-            assert_eq!(prev_ep.block_hash(), ep.execution_payload.parent_hash);
+            assert_eq!(prev_ep.block_hash(), ep.execution_payload().parent_hash());
             assert_eq!(
-                prev_ep.execution_payload.block_number + 1,
-                ep.execution_payload.block_number
+                prev_ep.execution_payload().block_number() + 1,
+                ep.execution_payload().block_number()
             );
-            assert!(ep.execution_payload.timestamp > prev_ep.execution_payload.timestamp);
+            assert!(ep.execution_payload().timestamp() > prev_ep.execution_payload().timestamp());
         }
         prev_ep = Some(ep.clone());
     }
@@ -88,7 +88,7 @@ async fn merge_with_terminal_block_hash_override() {
         if i == 0 {
             assert_eq!(execution_payload.block_hash(), genesis_pow_block_hash);
         }
-        execution_payloads.push(execution_payload);
+        execution_payloads.push(execution_payload.into());
     }
 
     verify_execution_payload_chain(execution_payloads.as_slice());
@@ -139,9 +139,14 @@ async fn base_altair_merge_with_terminal_block_after_fork() {
     let merge_head = &harness.chain.head_snapshot().beacon_block;
     assert!(merge_head.as_merge().is_ok());
     assert_eq!(merge_head.slot(), merge_fork_slot);
-    assert_eq!(
-        *merge_head.message().body().execution_payload().unwrap(),
-        FullPayload::default()
+    assert!(
+        merge_head
+            .message()
+            .body()
+            .execution_payload()
+            .unwrap()
+            .is_default_with_empty_roots(),
+        "Merge head is default payload"
     );
 
     /*
@@ -151,13 +156,14 @@ async fn base_altair_merge_with_terminal_block_after_fork() {
     harness.extend_slots(1).await;
 
     let one_after_merge_head = &harness.chain.head_snapshot().beacon_block;
-    assert_eq!(
-        *one_after_merge_head
+    assert!(
+        one_after_merge_head
             .message()
             .body()
             .execution_payload()
-            .unwrap(),
-        FullPayload::default()
+            .unwrap()
+            .is_default_with_empty_roots(),
+        "One after merge head is default payload"
     );
     assert_eq!(one_after_merge_head.slot(), merge_fork_slot + 1);
 
@@ -184,25 +190,34 @@ async fn base_altair_merge_with_terminal_block_after_fork() {
     harness.extend_slots(1).await;
 
     let one_after_merge_head = &harness.chain.head_snapshot().beacon_block;
-    assert_eq!(
-        *one_after_merge_head
+    // FIXME: why is this being tested twice?
+    assert!(
+        one_after_merge_head
             .message()
             .body()
             .execution_payload()
-            .unwrap(),
-        FullPayload::default()
+            .unwrap()
+            .is_default_with_empty_roots(),
+        "One after merge head is default payload"
     );
     assert_eq!(one_after_merge_head.slot(), merge_fork_slot + 2);
 
     /*
      * Next merge block should include an exec payload.
      */
-
     for _ in 0..4 {
         harness.extend_slots(1).await;
 
         let block = &harness.chain.head_snapshot().beacon_block;
-        execution_payloads.push(block.message().body().execution_payload().unwrap().clone());
+        execution_payloads.push(
+            block
+                .message()
+                .body()
+                .execution_payload()
+                .unwrap()
+                .clone()
+                .into(),
+        );
     }
 
     verify_execution_payload_chain(execution_payloads.as_slice());
diff --git a/beacon_node/beacon_chain/tests/payload_invalidation.rs b/beacon_node/beacon_chain/tests/payload_invalidation.rs
index 611b20988..35065a442 100644
--- a/beacon_node/beacon_chain/tests/payload_invalidation.rs
+++ b/beacon_node/beacon_chain/tests/payload_invalidation.rs
@@ -7,12 +7,12 @@ use beacon_chain::otb_verification_service::{
 use beacon_chain::{
     canonical_head::{CachedHead, CanonicalHead},
     test_utils::{BeaconChainHarness, EphemeralHarnessType},
-    BeaconChainError, BlockError, ExecutionPayloadError, StateSkipConfig, WhenSlotSkipped,
-    INVALID_FINALIZED_MERGE_TRANSITION_BLOCK_SHUTDOWN_REASON,
+    BeaconChainError, BlockError, ExecutionPayloadError, NotifyExecutionLayer, StateSkipConfig,
+    WhenSlotSkipped, INVALID_FINALIZED_MERGE_TRANSITION_BLOCK_SHUTDOWN_REASON,
     INVALID_JUSTIFIED_PAYLOAD_SHUTDOWN_REASON,
 };
 use execution_layer::{
-    json_structures::{JsonForkchoiceStateV1, JsonPayloadAttributesV1},
+    json_structures::{JsonForkchoiceStateV1, JsonPayloadAttributes, JsonPayloadAttributesV1},
     test_utils::ExecutionBlockGenerator,
     ExecutionLayer, ForkchoiceState, PayloadAttributes,
 };
@@ -133,7 +133,10 @@ impl InvalidPayloadRig {
         let attributes: JsonPayloadAttributesV1 =
             serde_json::from_value(payload_param_json.clone()).unwrap();
 
-        (fork_choice_state.into(), attributes.into())
+        (
+            fork_choice_state.into(),
+            JsonPayloadAttributes::V1(attributes).into(),
+        )
     }
 
     fn previous_payload_attributes(&self) -> PayloadAttributes {
@@ -693,6 +696,7 @@ async fn invalidates_all_descendants() {
             fork_block.canonical_root(),
             Arc::new(fork_block),
             CountUnrealized::True,
+            NotifyExecutionLayer::Yes,
         )
         .await
         .unwrap();
@@ -789,6 +793,7 @@ async fn switches_heads() {
             fork_block.canonical_root(),
             Arc::new(fork_block),
             CountUnrealized::True,
+            NotifyExecutionLayer::Yes,
         )
         .await
         .unwrap();
@@ -982,20 +987,22 @@ async fn payload_preparation() {
         .await
         .unwrap();
 
-    let payload_attributes = PayloadAttributes {
-        timestamp: rig
-            .harness
+    let payload_attributes = PayloadAttributes::new(
+        rig.harness
             .chain
             .slot_clock
             .start_of(next_slot)
             .unwrap()
             .as_secs(),
-        prev_randao: *head
+        *head
             .beacon_state
             .get_randao_mix(head.beacon_state.current_epoch())
             .unwrap(),
-        suggested_fee_recipient: fee_recipient,
-    };
+        fee_recipient,
+        None,
+    )
+    .downgrade_to_v1()
+    .unwrap();
     assert_eq!(rig.previous_payload_attributes(), payload_attributes);
 }
 
@@ -1035,7 +1042,7 @@ async fn invalid_parent() {
 
     // Ensure the block built atop an invalid payload is invalid for import.
     assert!(matches!(
-        rig.harness.chain.process_block(block.canonical_root(), block.clone(), CountUnrealized::True).await,
+        rig.harness.chain.process_block(block.canonical_root(), block.clone(), CountUnrealized::True, NotifyExecutionLayer::Yes).await,
         Err(BlockError::ParentExecutionPayloadInvalid { parent_root: invalid_root })
         if invalid_root == parent_root
     ));
@@ -1125,7 +1132,7 @@ async fn payload_preparation_before_transition_block() {
 
     let (fork_choice_state, payload_attributes) = rig.previous_forkchoice_update_params();
     let latest_block_hash = rig.latest_execution_block_hash();
-    assert_eq!(payload_attributes.suggested_fee_recipient, fee_recipient);
+    assert_eq!(payload_attributes.suggested_fee_recipient(), fee_recipient);
     assert_eq!(fork_choice_state.head_block_hash, latest_block_hash);
 }
 
@@ -1317,7 +1324,12 @@ async fn build_optimistic_chain(
     for block in blocks {
         rig.harness
             .chain
-            .process_block(block.canonical_root(), block, CountUnrealized::True)
+            .process_block(
+                block.canonical_root(),
+                block,
+                CountUnrealized::True,
+                NotifyExecutionLayer::Yes,
+            )
             .await
             .unwrap();
     }
@@ -1367,18 +1379,16 @@ async fn build_optimistic_chain(
             .body()
             .execution_payload()
             .unwrap()
-            .execution_payload
-            == <_>::default(),
+            .is_default_with_empty_roots(),
         "the block *has not* undergone the merge transition"
     );
     assert!(
-        post_transition_block
+        !post_transition_block
             .message()
             .body()
             .execution_payload()
             .unwrap()
-            .execution_payload
-            != <_>::default(),
+            .is_default_with_empty_roots(),
         "the block *has* undergone the merge transition"
     );
 
@@ -1879,6 +1889,7 @@ async fn recover_from_invalid_head_by_importing_blocks() {
             fork_block.canonical_root(),
             fork_block.clone(),
             CountUnrealized::True,
+            NotifyExecutionLayer::Yes,
         )
         .await
         .unwrap();
diff --git a/beacon_node/beacon_chain/tests/store_tests.rs b/beacon_node/beacon_chain/tests/store_tests.rs
index b1907bc96..b2fc7a640 100644
--- a/beacon_node/beacon_chain/tests/store_tests.rs
+++ b/beacon_node/beacon_chain/tests/store_tests.rs
@@ -7,8 +7,8 @@ use beacon_chain::test_utils::{
 };
 use beacon_chain::{
     historical_blocks::HistoricalBlockError, migrate::MigratorConfig, BeaconChain,
-    BeaconChainError, BeaconChainTypes, BeaconSnapshot, ChainConfig, ServerSentEventHandler,
-    WhenSlotSkipped,
+    BeaconChainError, BeaconChainTypes, BeaconSnapshot, ChainConfig, NotifyExecutionLayer,
+    ServerSentEventHandler, WhenSlotSkipped,
 };
 use fork_choice::CountUnrealized;
 use lazy_static::lazy_static;
@@ -2148,6 +2148,7 @@ async fn weak_subjectivity_sync() {
                 full_block.canonical_root(),
                 Arc::new(full_block),
                 CountUnrealized::True,
+                NotifyExecutionLayer::Yes,
             )
             .await
             .unwrap();
diff --git a/beacon_node/beacon_chain/tests/tests.rs b/beacon_node/beacon_chain/tests/tests.rs
index a13946bf2..d80db132e 100644
--- a/beacon_node/beacon_chain/tests/tests.rs
+++ b/beacon_node/beacon_chain/tests/tests.rs
@@ -6,7 +6,7 @@ use beacon_chain::{
         AttestationStrategy, BeaconChainHarness, BlockStrategy, EphemeralHarnessType,
         OP_POOL_DB_KEY,
     },
-    BeaconChain, StateSkipConfig, WhenSlotSkipped,
+    BeaconChain, NotifyExecutionLayer, StateSkipConfig, WhenSlotSkipped,
 };
 use fork_choice::CountUnrealized;
 use lazy_static::lazy_static;
@@ -687,7 +687,8 @@ async fn run_skip_slot_test(skip_slots: u64) {
             .process_block(
                 harness_a.chain.head_snapshot().beacon_block_root,
                 harness_a.chain.head_snapshot().beacon_block.clone(),
-                CountUnrealized::True
+                CountUnrealized::True,
+                NotifyExecutionLayer::Yes,
             )
             .await
             .unwrap(),
diff --git a/beacon_node/client/src/builder.rs b/beacon_node/client/src/builder.rs
index 150afeacb..edd2815f8 100644
--- a/beacon_node/client/src/builder.rs
+++ b/beacon_node/client/src/builder.rs
@@ -40,9 +40,6 @@ use types::{
 /// Interval between polling the eth1 node for genesis information.
 pub const ETH1_GENESIS_UPDATE_INTERVAL_MILLIS: u64 = 7_000;
 
-/// Timeout for checkpoint sync HTTP requests.
-pub const CHECKPOINT_SYNC_HTTP_TIMEOUT: Duration = Duration::from_secs(60);
-
 /// Builds a `Client` instance.
 ///
 /// ## Notes
@@ -279,8 +276,12 @@ where
                     "remote_url" => %url,
                 );
 
-                let remote =
-                    BeaconNodeHttpClient::new(url, Timeouts::set_all(CHECKPOINT_SYNC_HTTP_TIMEOUT));
+                let remote = BeaconNodeHttpClient::new(
+                    url,
+                    Timeouts::set_all(Duration::from_secs(
+                        config.chain.checkpoint_sync_url_timeout,
+                    )),
+                );
                 let slots_per_epoch = TEthSpec::slots_per_epoch();
 
                 let deposit_snapshot = if config.sync_eth1_chain {
diff --git a/beacon_node/client/src/config.rs b/beacon_node/client/src/config.rs
index 3a8b2db3e..e3c0ccd52 100644
--- a/beacon_node/client/src/config.rs
+++ b/beacon_node/client/src/config.rs
@@ -42,7 +42,7 @@ pub enum ClientGenesis {
 /// The core configuration of a Lighthouse beacon node.
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct Config {
-    pub data_dir: PathBuf,
+    data_dir: PathBuf,
     /// Name of the directory inside the data directory where the main "hot" DB is located.
     pub db_name: String,
     /// Path where the freezer database will be located.
@@ -105,6 +105,17 @@ impl Default for Config {
 }
 
 impl Config {
+    /// Updates the data directory for the Client.
+    pub fn set_data_dir(&mut self, data_dir: PathBuf) {
+        self.data_dir = data_dir.clone();
+        self.http_api.data_dir = data_dir;
+    }
+
+    /// Gets the config's data_dir.
+    pub fn data_dir(&self) -> &PathBuf {
+        &self.data_dir
+    }
+
     /// Get the database path without initialising it.
     pub fn get_db_path(&self) -> PathBuf {
         self.get_data_dir().join(&self.db_name)
diff --git a/beacon_node/eth1/src/service.rs b/beacon_node/eth1/src/service.rs
index f24b746cd..31082394b 100644
--- a/beacon_node/eth1/src/service.rs
+++ b/beacon_node/eth1/src/service.rs
@@ -751,10 +751,11 @@ impl Service {
             let deposit_count_to_finalize = eth1data_to_finalize.deposit_count;
             if deposit_count_to_finalize > already_finalized {
                 match self.finalize_deposits(eth1data_to_finalize) {
-                    Err(e) => error!(
+                    Err(e) => warn!(
                         self.log,
                         "Failed to finalize deposit cache";
                         "error" => ?e,
+                        "info" => "this should resolve on its own"
                     ),
                     Ok(()) => info!(
                         self.log,
@@ -814,9 +815,10 @@ impl Service {
             .block_by_hash(&eth1_data.block_hash)
             .cloned()
             .ok_or_else(|| {
-                Error::FailedToFinalizeDeposit(
-                    "Finalized block not found in block cache".to_string(),
-                )
+                Error::FailedToFinalizeDeposit(format!(
+                    "Finalized block not found in block cache: {:?}",
+                    eth1_data.block_hash
+                ))
             })?;
         self.inner
             .deposit_cache
diff --git a/beacon_node/execution_layer/src/engine_api.rs b/beacon_node/execution_layer/src/engine_api.rs
index b1a3cfa41..988b04826 100644
--- a/beacon_node/execution_layer/src/engine_api.rs
+++ b/beacon_node/execution_layer/src/engine_api.rs
@@ -7,11 +7,9 @@ use reqwest::StatusCode;
 use serde::{Deserialize, Serialize};
 use strum::IntoStaticStr;
 use superstruct::superstruct;
-#[cfg(feature = "withdrawals")]
-use types::Withdrawal;
 pub use types::{
     Address, EthSpec, ExecutionBlockHash, ExecutionPayload, ExecutionPayloadHeader, FixedVector,
-    ForkName, Hash256, Uint256, VariableList,
+    ForkName, Hash256, Uint256, VariableList, Withdrawal,
 };
 
 pub mod auth;
@@ -245,11 +243,11 @@ impl<T: EthSpec> From<ExecutionPayload<T>> for ExecutionBlockWithTransactions<T>
 
 #[superstruct(
     variants(V1, V2),
-    variant_attributes(derive(Clone, Debug, PartialEq),),
+    variant_attributes(derive(Clone, Debug, Eq, Hash, PartialEq),),
     cast_error(ty = "Error", expr = "Error::IncorrectStateVariant"),
     partial_getter_error(ty = "Error", expr = "Error::IncorrectStateVariant")
 )]
-#[derive(Clone, Debug, PartialEq)]
+#[derive(Clone, Debug, Eq, Hash, PartialEq)]
 pub struct PayloadAttributes {
     #[superstruct(getter(copy))]
     pub timestamp: u64,
@@ -257,20 +255,33 @@ pub struct PayloadAttributes {
     pub prev_randao: Hash256,
     #[superstruct(getter(copy))]
     pub suggested_fee_recipient: Address,
-    #[cfg(feature = "withdrawals")]
     #[superstruct(only(V2))]
     pub withdrawals: Option<Vec<Withdrawal>>,
 }
 
 impl PayloadAttributes {
+    pub fn new(
+        timestamp: u64,
+        prev_randao: Hash256,
+        suggested_fee_recipient: Address,
+        withdrawals: Option<Vec<Withdrawal>>,
+    ) -> Self {
+        // this should always return the highest version
+        PayloadAttributes::V2(PayloadAttributesV2 {
+            timestamp,
+            prev_randao,
+            suggested_fee_recipient,
+            withdrawals,
+        })
+    }
+
     pub fn downgrade_to_v1(self) -> Result<Self, Error> {
         match self {
             PayloadAttributes::V1(_) => Ok(self),
             PayloadAttributes::V2(v2) => {
-                #[cfg(features = "withdrawals")]
                 if v2.withdrawals.is_some() {
                     return Err(Error::BadConversion(
-                        "Downgrading from PayloadAttributesV2 with non-null withdrawaals"
+                        "Downgrading from PayloadAttributesV2 with non-null withdrawals"
                             .to_string(),
                     ));
                 }
diff --git a/beacon_node/execution_layer/src/engine_api/json_structures.rs b/beacon_node/execution_layer/src/engine_api/json_structures.rs
index dae0d8e5d..9b729167b 100644
--- a/beacon_node/execution_layer/src/engine_api/json_structures.rs
+++ b/beacon_node/execution_layer/src/engine_api/json_structures.rs
@@ -375,8 +375,9 @@ pub struct JsonPayloadAttributes {
     pub timestamp: u64,
     pub prev_randao: Hash256,
     pub suggested_fee_recipient: Address,
-    #[cfg(feature = "withdrawals")]
     #[superstruct(only(V2))]
+    #[serde(skip_serializing_if = "Option::is_none")]
+    #[serde(default)]
     pub withdrawals: Option<Vec<JsonWithdrawal>>,
 }
 
@@ -392,7 +393,6 @@ impl From<PayloadAttributes> for JsonPayloadAttributes {
                 timestamp: pa.timestamp,
                 prev_randao: pa.prev_randao,
                 suggested_fee_recipient: pa.suggested_fee_recipient,
-                #[cfg(feature = "withdrawals")]
                 withdrawals: pa
                     .withdrawals
                     .map(|w| w.into_iter().map(Into::into).collect()),
@@ -413,7 +413,6 @@ impl From<JsonPayloadAttributes> for PayloadAttributes {
                 timestamp: jpa.timestamp,
                 prev_randao: jpa.prev_randao,
                 suggested_fee_recipient: jpa.suggested_fee_recipient,
-                #[cfg(feature = "withdrawals")]
                 withdrawals: jpa
                     .withdrawals
                     .map(|jw| jw.into_iter().map(Into::into).collect()),
diff --git a/beacon_node/execution_layer/src/engines.rs b/beacon_node/execution_layer/src/engines.rs
index 264303b5d..b5792e383 100644
--- a/beacon_node/execution_layer/src/engines.rs
+++ b/beacon_node/execution_layer/src/engines.rs
@@ -16,6 +16,7 @@ use types::{Address, ExecutionBlockHash, Hash256};
 /// The number of payload IDs that will be stored for each `Engine`.
 ///
 /// Since the size of each value is small (~100 bytes) a large number is used for safety.
+/// FIXME: check this assumption now that the key includes entire payload attributes which now includes withdrawals
 const PAYLOAD_ID_LRU_CACHE_SIZE: usize = 512;
 
 /// Stores the remembered state of a engine.
@@ -97,9 +98,7 @@ pub struct ForkchoiceState {
 #[derive(Hash, PartialEq, std::cmp::Eq)]
 struct PayloadIdCacheKey {
     pub head_block_hash: ExecutionBlockHash,
-    pub timestamp: u64,
-    pub prev_randao: Hash256,
-    pub suggested_fee_recipient: Address,
+    pub payload_attributes: PayloadAttributes,
 }
 
 #[derive(Debug)]
@@ -142,20 +141,13 @@ impl Engine {
 
     pub async fn get_payload_id(
         &self,
-        head_block_hash: ExecutionBlockHash,
-        timestamp: u64,
-        prev_randao: Hash256,
-        suggested_fee_recipient: Address,
+        head_block_hash: &ExecutionBlockHash,
+        payload_attributes: &PayloadAttributes,
     ) -> Option<PayloadId> {
         self.payload_id_cache
             .lock()
             .await
-            .get(&PayloadIdCacheKey {
-                head_block_hash,
-                timestamp,
-                prev_randao,
-                suggested_fee_recipient,
-            })
+            .get(&PayloadIdCacheKey::new(head_block_hash, payload_attributes))
             .cloned()
     }
 
@@ -171,8 +163,8 @@ impl Engine {
             .await?;
 
         if let Some(payload_id) = response.payload_id {
-            if let Some(key) =
-                payload_attributes.map(|pa| PayloadIdCacheKey::new(&forkchoice_state, &pa))
+            if let Some(key) = payload_attributes
+                .map(|pa| PayloadIdCacheKey::new(&forkchoice_state.head_block_hash, &pa))
             {
                 self.payload_id_cache.lock().await.put(key, payload_id);
             } else {
@@ -347,14 +339,11 @@ impl Engine {
     }
 }
 
-// TODO: revisit this - do we need to key on withdrawals as well here?
 impl PayloadIdCacheKey {
-    fn new(state: &ForkchoiceState, attributes: &PayloadAttributes) -> Self {
+    fn new(head_block_hash: &ExecutionBlockHash, attributes: &PayloadAttributes) -> Self {
         Self {
-            head_block_hash: state.head_block_hash,
-            timestamp: attributes.timestamp(),
-            prev_randao: attributes.prev_randao(),
-            suggested_fee_recipient: attributes.suggested_fee_recipient(),
+            head_block_hash: head_block_hash.clone(),
+            payload_attributes: attributes.clone(),
         }
     }
 }
diff --git a/beacon_node/execution_layer/src/lib.rs b/beacon_node/execution_layer/src/lib.rs
index 3975e5b54..0f4f5cab2 100644
--- a/beacon_node/execution_layer/src/lib.rs
+++ b/beacon_node/execution_layer/src/lib.rs
@@ -12,6 +12,7 @@ pub use engine_api::*;
 pub use engine_api::{http, http::deposit_methods, http::HttpJsonRpc};
 use engines::{Engine, EngineError};
 pub use engines::{EngineState, ForkchoiceState};
+use eth2::types::{builder_bid::SignedBuilderBid, ForkVersionedResponse};
 use fork_choice::ForkchoiceUpdateParameters;
 use lru::LruCache;
 use payload_status::process_payload_status;
@@ -21,11 +22,13 @@ use serde::{Deserialize, Serialize};
 use slog::{crit, debug, error, info, trace, warn, Logger};
 use slot_clock::SlotClock;
 use std::collections::HashMap;
+use std::fmt;
 use std::future::Future;
 use std::io::Write;
 use std::path::PathBuf;
 use std::sync::Arc;
-use std::time::{Duration, SystemTime, UNIX_EPOCH};
+use std::time::{Duration, Instant, SystemTime, UNIX_EPOCH};
+use strum::AsRefStr;
 use task_executor::TaskExecutor;
 use tokio::{
     sync::{Mutex, MutexGuard, RwLock},
@@ -34,12 +37,14 @@ use tokio::{
 use tokio_stream::wrappers::WatchStream;
 #[cfg(feature = "withdrawals")]
 use types::Withdrawal;
-use types::{AbstractExecPayload, Blob, ExecPayload, ExecutionPayloadEip4844, KzgCommitment};
+use types::{AbstractExecPayload, Blob, ExecPayload, KzgCommitment};
 use types::{
     BlindedPayload, BlockType, ChainSpec, Epoch, ExecutionBlockHash, ForkName,
-    ProposerPreparationData, PublicKeyBytes, SignedBeaconBlock, Slot,
+    ProposerPreparationData, PublicKeyBytes, Signature, SignedBeaconBlock, Slot, Uint256,
+};
+use types::{
+    ExecutionPayload, ExecutionPayloadCapella, ExecutionPayloadEip4844, ExecutionPayloadMerge,
 };
-use types::{ExecutionPayload, ExecutionPayloadCapella, ExecutionPayloadMerge};
 
 mod engine_api;
 mod engines;
@@ -70,6 +75,14 @@ const DEFAULT_SUGGESTED_FEE_RECIPIENT: [u8; 20] =
 
 const CONFIG_POLL_INTERVAL: Duration = Duration::from_secs(60);
 
+/// A payload alongside some information about where it came from.
+enum ProvenancedPayload<P> {
+    /// A good ol' fashioned farm-to-table payload from your local EE.
+    Local(P),
+    /// A payload from a builder (e.g. mev-boost).
+    Builder(P),
+}
+
 #[derive(Debug)]
 pub enum Error {
     NoEngine,
@@ -77,6 +90,7 @@ pub enum Error {
     ApiError(ApiError),
     Builder(builder_client::Error),
     NoHeaderFromBuilder,
+    CannotProduceHeader,
     EngineError(Box<EngineError>),
     NotSynced,
     ShuttingDown,
@@ -602,22 +616,16 @@ impl<T: EthSpec> ExecutionLayer<T> {
     ///
     /// The result will be returned from the first node that returns successfully. No more nodes
     /// will be contacted.
-    #[allow(clippy::too_many_arguments)]
     pub async fn get_payload<Payload: AbstractExecPayload<T>>(
         &self,
         parent_hash: ExecutionBlockHash,
-        timestamp: u64,
-        prev_randao: Hash256,
-        proposer_index: u64,
+        payload_attributes: &PayloadAttributes,
         forkchoice_update_params: ForkchoiceUpdateParameters,
         builder_params: BuilderParams,
         current_fork: ForkName,
-        #[cfg(feature = "withdrawals")] withdrawals: Option<Vec<Withdrawal>>,
         spec: &ChainSpec,
     ) -> Result<BlockProposalContents<T, Payload>, Error> {
-        let suggested_fee_recipient = self.get_suggested_fee_recipient(proposer_index).await;
-
-        match Payload::block_type() {
+        let payload_result = match Payload::block_type() {
             BlockType::Blinded => {
                 let _timer = metrics::start_timer_vec(
                     &metrics::EXECUTION_LAYER_REQUEST_TIMES,
@@ -625,14 +633,10 @@ impl<T: EthSpec> ExecutionLayer<T> {
                 );
                 self.get_blinded_payload(
                     parent_hash,
-                    timestamp,
-                    prev_randao,
-                    suggested_fee_recipient,
+                    payload_attributes,
                     forkchoice_update_params,
                     builder_params,
                     current_fork,
-                    #[cfg(feature = "withdrawals")]
-                    withdrawals,
                     spec,
                 )
                 .await
@@ -644,32 +648,58 @@ impl<T: EthSpec> ExecutionLayer<T> {
                 );
                 self.get_full_payload(
                     parent_hash,
-                    timestamp,
-                    prev_randao,
-                    suggested_fee_recipient,
+                    payload_attributes,
                     forkchoice_update_params,
                     current_fork,
-                    #[cfg(feature = "withdrawals")]
-                    withdrawals,
                 )
                 .await
+                .map(ProvenancedPayload::Local)
+            }
+        };
+
+        // Track some metrics and return the result.
+        match payload_result {
+            Ok(ProvenancedPayload::Local(block_proposal_contents)) => {
+                metrics::inc_counter_vec(
+                    &metrics::EXECUTION_LAYER_GET_PAYLOAD_OUTCOME,
+                    &[metrics::SUCCESS],
+                );
+                metrics::inc_counter_vec(
+                    &metrics::EXECUTION_LAYER_GET_PAYLOAD_SOURCE,
+                    &[metrics::LOCAL],
+                );
+                Ok(block_proposal_contents)
+            }
+            Ok(ProvenancedPayload::Builder(block_proposal_contents)) => {
+                metrics::inc_counter_vec(
+                    &metrics::EXECUTION_LAYER_GET_PAYLOAD_OUTCOME,
+                    &[metrics::SUCCESS],
+                );
+                metrics::inc_counter_vec(
+                    &metrics::EXECUTION_LAYER_GET_PAYLOAD_SOURCE,
+                    &[metrics::BUILDER],
+                );
+                Ok(block_proposal_contents)
+            }
+            Err(e) => {
+                metrics::inc_counter_vec(
+                    &metrics::EXECUTION_LAYER_GET_PAYLOAD_OUTCOME,
+                    &[metrics::FAILURE],
+                );
+                Err(e)
             }
         }
     }
 
-    #[allow(clippy::too_many_arguments)]
     async fn get_blinded_payload<Payload: AbstractExecPayload<T>>(
         &self,
         parent_hash: ExecutionBlockHash,
-        timestamp: u64,
-        prev_randao: Hash256,
-        suggested_fee_recipient: Address,
+        payload_attributes: &PayloadAttributes,
         forkchoice_update_params: ForkchoiceUpdateParameters,
         builder_params: BuilderParams,
         current_fork: ForkName,
-        #[cfg(feature = "withdrawals")] withdrawals: Option<Vec<Withdrawal>>,
         spec: &ChainSpec,
-    ) -> Result<BlockProposalContents<T, Payload>, Error> {
+    ) -> Result<ProvenancedPayload<BlockProposalContents<T, Payload>>, Error> {
         if let Some(builder) = self.builder() {
             let slot = builder_params.slot;
             let pubkey = builder_params.pubkey;
@@ -683,173 +713,238 @@ impl<T: EthSpec> ExecutionLayer<T> {
                         "pubkey" => ?pubkey,
                         "parent_hash" => ?parent_hash,
                     );
-                    let (relay_result, local_result) = tokio::join!(
-                        builder.get_builder_header::<T, Payload>(slot, parent_hash, &pubkey),
-                        self.get_full_payload_caching(
-                            parent_hash,
-                            timestamp,
-                            prev_randao,
-                            suggested_fee_recipient,
-                            forkchoice_update_params,
-                            current_fork,
-                            #[cfg(feature = "withdrawals")]
-                            withdrawals,
-                        )
+
+                    // Wait for the builder *and* local EL to produce a payload (or return an error).
+                    let ((relay_result, relay_duration), (local_result, local_duration)) = tokio::join!(
+                        timed_future(metrics::GET_BLINDED_PAYLOAD_BUILDER, async {
+                            builder
+                                .get_builder_header::<T, Payload>(slot, parent_hash, &pubkey)
+                                .await
+                        }),
+                        timed_future(metrics::GET_BLINDED_PAYLOAD_LOCAL, async {
+                            self.get_full_payload_caching::<Payload>(
+                                parent_hash,
+                                payload_attributes,
+                                forkchoice_update_params,
+                                current_fork,
+                            )
+                            .await
+                        })
+                    );
+
+                    info!(
+                        self.log(),
+                        "Requested blinded execution payload";
+                        "relay_fee_recipient" => match &relay_result {
+                            Ok(Some(r)) => format!("{:?}", r.data.message.header.fee_recipient()),
+                            Ok(None) => "empty response".to_string(),
+                            Err(_) => "request failed".to_string(),
+                        },
+                        "relay_response_ms" => relay_duration.as_millis(),
+                        "local_fee_recipient" => match &local_result {
+                            Ok(proposal_contents) => format!("{:?}", proposal_contents.payload().fee_recipient()),
+                            Err(_) => "request failed".to_string()
+                        },
+                        "local_response_ms" => local_duration.as_millis(),
+                        "parent_hash" => ?parent_hash,
                     );
 
                     return match (relay_result, local_result) {
                         (Err(e), Ok(local)) => {
                             warn!(
                                 self.log(),
-                                "Unable to retrieve a payload from a connected \
-                                builder, falling back to the local execution client: {e:?}"
+                                "Builder error when requesting payload";
+                                "info" => "falling back to local execution client",
+                                "relay_error" => ?e,
+                                "local_block_hash" => ?local.payload().block_hash(),
+                                "parent_hash" => ?parent_hash,
                             );
-                            Ok(local)
+                            Ok(ProvenancedPayload::Local(local))
                         }
                         (Ok(None), Ok(local)) => {
                             info!(
                                 self.log(),
-                                "No payload provided by connected builder. \
-                                Attempting to propose through local execution engine"
+                                "Builder did not return a payload";
+                                "info" => "falling back to local execution client",
+                                "local_block_hash" => ?local.payload().block_hash(),
+                                "parent_hash" => ?parent_hash,
                             );
-                            Ok(local)
+                            Ok(ProvenancedPayload::Local(local))
                         }
                         (Ok(Some(relay)), Ok(local)) => {
-                            let local_payload = local.payload();
-                            let is_signature_valid = relay.data.verify_signature(spec);
-                            let header = relay.data.message.header;
+                            let header = &relay.data.message.header;
 
                             info!(
                                 self.log(),
-                                "Received a payload header from the connected builder";
-                                "block_hash" => ?header.block_hash(),
+                                "Received local and builder payloads";
+                                "relay_block_hash" => ?header.block_hash(),
+                                "local_block_hash" => ?local.payload().block_hash(),
+                                "parent_hash" => ?parent_hash,
                             );
 
-                            let relay_value = relay.data.message.value;
-                            let configured_value = self.inner.builder_profit_threshold;
-                            if relay_value < configured_value {
-                                info!(
-                                        self.log(),
-                                        "The value offered by the connected builder does not meet \
-                                        the configured profit threshold. Using local payload.";
-                                        "configured_value" => ?configured_value, "relay_value" => ?relay_value
-                                    );
-                                Ok(local)
-                            } else if header.parent_hash() != parent_hash {
-                                warn!(
-                                    self.log(),
-                                    "Invalid parent hash from connected builder, \
-                                    falling back to local execution engine."
-                                );
-                                Ok(local)
-                            } else if header.prev_randao() != prev_randao {
-                                warn!(
-                                    self.log(),
-                                    "Invalid prev randao from connected builder, \
-                                    falling back to local execution engine."
-                                );
-                                Ok(local)
-                            } else if header.timestamp() != local_payload.timestamp() {
-                                warn!(
-                                    self.log(),
-                                    "Invalid timestamp from connected builder, \
-                                    falling back to local execution engine."
-                                );
-                                Ok(local)
-                            } else if header.block_number() != local_payload.block_number() {
-                                warn!(
-                                    self.log(),
-                                    "Invalid block number from connected builder, \
-                                    falling back to local execution engine."
-                                );
-                                Ok(local)
-                            } else if !matches!(relay.version, Some(ForkName::Merge)) {
-                                // Once fork information is added to the payload, we will need to
-                                // check that the local and relay payloads match. At this point, if
-                                // we are requesting a payload at all, we have to assume this is
-                                // the Bellatrix fork.
-                                warn!(
-                                    self.log(),
-                                    "Invalid fork from connected builder, falling \
-                                    back to local execution engine."
-                                );
-                                Ok(local)
-                            } else if !is_signature_valid {
-                                let pubkey_bytes = relay.data.message.pubkey;
-                                warn!(self.log(), "Invalid signature for pubkey {pubkey_bytes} on \
-                                    bid from connected builder, falling back to local execution engine.");
-                                Ok(local)
-                            } else {
-                                if header.fee_recipient() != suggested_fee_recipient {
+                            match verify_builder_bid(
+                                &relay,
+                                parent_hash,
+                                payload_attributes.prev_randao(),
+                                payload_attributes.timestamp(),
+                                Some(local.payload().block_number()),
+                                self.inner.builder_profit_threshold,
+                                spec,
+                            ) {
+                                Ok(()) => Ok(ProvenancedPayload::Builder(
+                                    //FIXME(sean) the builder API needs to be updated
+                                    // NOTE       the comment above was removed in the
+                                    //            rebase with unstable.. I think it goes
+                                    //            here now?
+                                    BlockProposalContents::Payload(relay.data.message.header),
+                                )),
+                                Err(reason) if !reason.payload_invalid() => {
                                     info!(
                                         self.log(),
-                                        "Fee recipient from connected builder does \
-                                        not match, using it anyways."
+                                        "Builder payload ignored";
+                                        "info" => "using local payload",
+                                        "reason" => %reason,
+                                        "relay_block_hash" => ?header.block_hash(),
+                                        "parent_hash" => ?parent_hash,
                                     );
+                                    Ok(ProvenancedPayload::Local(local))
+                                }
+                                Err(reason) => {
+                                    metrics::inc_counter_vec(
+                                        &metrics::EXECUTION_LAYER_GET_PAYLOAD_BUILDER_REJECTIONS,
+                                        &[reason.as_ref().as_ref()],
+                                    );
+                                    warn!(
+                                        self.log(),
+                                        "Builder returned invalid payload";
+                                        "info" => "using local payload",
+                                        "reason" => %reason,
+                                        "relay_block_hash" => ?header.block_hash(),
+                                        "parent_hash" => ?parent_hash,
+                                    );
+                                    Ok(ProvenancedPayload::Local(local))
                                 }
-                                //FIXME(sean) the builder API needs to be updated
-                                Ok(BlockProposalContents::Payload(header))
                             }
                         }
-                        (relay_result, Err(local_error)) => {
-                            warn!(self.log(), "Failure from local execution engine. Attempting to \
-                                propose through connected builder"; "error" => ?local_error);
-                            relay_result
-                                .map_err(Error::Builder)?
-                                .ok_or(Error::NoHeaderFromBuilder)
-                                .map(|d| {
+                        (Ok(Some(relay)), Err(local_error)) => {
+                            let header = &relay.data.message.header;
+
+                            info!(
+                                self.log(),
+                                "Received builder payload with local error";
+                                "relay_block_hash" => ?header.block_hash(),
+                                "local_error" => ?local_error,
+                                "parent_hash" => ?parent_hash,
+                            );
+
+                            match verify_builder_bid(
+                                &relay,
+                                parent_hash,
+                                payload_attributes.prev_randao(),
+                                payload_attributes.timestamp(),
+                                None,
+                                self.inner.builder_profit_threshold,
+                                spec,
+                            ) {
+                                Ok(()) => Ok(ProvenancedPayload::Builder(
                                     //FIXME(sean) the builder API needs to be updated
-                                    BlockProposalContents::Payload(d.data.message.header)
-                                })
+                                    // NOTE       the comment above was removed in the
+                                    //            rebase with unstable.. I think it goes
+                                    //            here now?
+                                    BlockProposalContents::Payload(relay.data.message.header),
+                                )),
+                                // If the payload is valid then use it. The local EE failed
+                                // to produce a payload so we have no alternative.
+                                Err(e) if !e.payload_invalid() => Ok(ProvenancedPayload::Builder(
+                                    //FIXME(sean) the builder API needs to be updated
+                                    // NOTE       the comment above was removed in the
+                                    //            rebase with unstable.. I think it goes
+                                    //            here now?
+                                    BlockProposalContents::Payload(relay.data.message.header),
+                                )),
+                                Err(reason) => {
+                                    metrics::inc_counter_vec(
+                                        &metrics::EXECUTION_LAYER_GET_PAYLOAD_BUILDER_REJECTIONS,
+                                        &[reason.as_ref().as_ref()],
+                                    );
+                                    crit!(
+                                        self.log(),
+                                        "Builder returned invalid payload";
+                                        "info" => "no local payload either - unable to propose block",
+                                        "reason" => %reason,
+                                        "relay_block_hash" => ?header.block_hash(),
+                                        "parent_hash" => ?parent_hash,
+                                    );
+                                    Err(Error::CannotProduceHeader)
+                                }
+                            }
+                        }
+                        (Err(relay_error), Err(local_error)) => {
+                            crit!(
+                                self.log(),
+                                "Unable to produce execution payload";
+                                "info" => "the local EL and builder both failed - unable to propose block",
+                                "relay_error" => ?relay_error,
+                                "local_error" => ?local_error,
+                                "parent_hash" => ?parent_hash,
+                            );
+
+                            Err(Error::CannotProduceHeader)
+                        }
+                        (Ok(None), Err(local_error)) => {
+                            crit!(
+                                self.log(),
+                                "Unable to produce execution payload";
+                                "info" => "the local EL failed and the builder returned nothing - \
+                                    the block proposal will be missed",
+                                "local_error" => ?local_error,
+                                "parent_hash" => ?parent_hash,
+                            );
+
+                            Err(Error::CannotProduceHeader)
                         }
                     };
                 }
-                ChainHealth::Unhealthy(condition) => {
-                    info!(self.log(), "Due to poor chain health the local execution engine will be used \
-                                        for payload construction. To adjust chain health conditions \
-                                        Use `builder-fallback` prefixed flags";
-                        "failed_condition" => ?condition)
-                }
+                ChainHealth::Unhealthy(condition) => info!(
+                    self.log(),
+                    "Chain is unhealthy, using local payload";
+                    "info" => "this helps protect the network. the --builder-fallback flags \
+                        can adjust the expected health conditions.",
+                    "failed_condition" => ?condition
+                ),
                 // Intentional no-op, so we never attempt builder API proposals pre-merge.
                 ChainHealth::PreMerge => (),
-                ChainHealth::Optimistic => info!(self.log(), "The local execution engine is syncing \
-                                            so the builder network cannot safely be used. Attempting \
-                                            to build a block with the local execution engine"),
+                ChainHealth::Optimistic => info!(
+                    self.log(),
+                    "Chain is optimistic; can't build payload";
+                    "info" => "the local execution engine is syncing and the builder network \
+                        cannot safely be used - unable to propose block"
+                ),
             }
         }
         self.get_full_payload_caching(
             parent_hash,
-            timestamp,
-            prev_randao,
-            suggested_fee_recipient,
+            payload_attributes,
             forkchoice_update_params,
             current_fork,
-            #[cfg(feature = "withdrawals")]
-            withdrawals,
         )
         .await
+        .map(ProvenancedPayload::Local)
     }
 
     /// Get a full payload without caching its result in the execution layer's payload cache.
     async fn get_full_payload<Payload: AbstractExecPayload<T>>(
         &self,
         parent_hash: ExecutionBlockHash,
-        timestamp: u64,
-        prev_randao: Hash256,
-        suggested_fee_recipient: Address,
+        payload_attributes: &PayloadAttributes,
         forkchoice_update_params: ForkchoiceUpdateParameters,
         current_fork: ForkName,
-        #[cfg(feature = "withdrawals")] withdrawals: Option<Vec<Withdrawal>>,
     ) -> Result<BlockProposalContents<T, Payload>, Error> {
         self.get_full_payload_with(
             parent_hash,
-            timestamp,
-            prev_randao,
-            suggested_fee_recipient,
+            payload_attributes,
             forkchoice_update_params,
             current_fork,
-            #[cfg(feature = "withdrawals")]
-            withdrawals,
             noop,
         )
         .await
@@ -859,22 +954,15 @@ impl<T: EthSpec> ExecutionLayer<T> {
     async fn get_full_payload_caching<Payload: AbstractExecPayload<T>>(
         &self,
         parent_hash: ExecutionBlockHash,
-        timestamp: u64,
-        prev_randao: Hash256,
-        suggested_fee_recipient: Address,
+        payload_attributes: &PayloadAttributes,
         forkchoice_update_params: ForkchoiceUpdateParameters,
         current_fork: ForkName,
-        #[cfg(feature = "withdrawals")] withdrawals: Option<Vec<Withdrawal>>,
     ) -> Result<BlockProposalContents<T, Payload>, Error> {
         self.get_full_payload_with(
             parent_hash,
-            timestamp,
-            prev_randao,
-            suggested_fee_recipient,
+            payload_attributes,
             forkchoice_update_params,
             current_fork,
-            #[cfg(feature = "withdrawals")]
-            withdrawals,
             Self::cache_payload,
         )
         .await
@@ -883,20 +971,15 @@ impl<T: EthSpec> ExecutionLayer<T> {
     async fn get_full_payload_with<Payload: AbstractExecPayload<T>>(
         &self,
         parent_hash: ExecutionBlockHash,
-        timestamp: u64,
-        prev_randao: Hash256,
-        suggested_fee_recipient: Address,
+        payload_attributes: &PayloadAttributes,
         forkchoice_update_params: ForkchoiceUpdateParameters,
         current_fork: ForkName,
-        #[cfg(feature = "withdrawals")] withdrawals: Option<Vec<Withdrawal>>,
         f: fn(&ExecutionLayer<T>, &ExecutionPayload<T>) -> Option<ExecutionPayload<T>>,
     ) -> Result<BlockProposalContents<T, Payload>, Error> {
-        #[cfg(feature = "withdrawals")]
-        let withdrawals_ref = &withdrawals;
         self.engine()
             .request(move |engine| async move {
                 let payload_id = if let Some(id) = engine
-                    .get_payload_id(parent_hash, timestamp, prev_randao, suggested_fee_recipient)
+                    .get_payload_id(&parent_hash, payload_attributes)
                     .await
                 {
                     // The payload id has been cached for this engine.
@@ -921,20 +1004,11 @@ impl<T: EthSpec> ExecutionLayer<T> {
                             .finalized_hash
                             .unwrap_or_else(ExecutionBlockHash::zero),
                     };
-                    // This must always be the latest PayloadAttributes
-                    // FIXME: How to non-capella EIP4844 testnets handle this?
-                    let payload_attributes = PayloadAttributes::V2(PayloadAttributesV2 {
-                        timestamp,
-                        prev_randao,
-                        suggested_fee_recipient,
-                        #[cfg(feature = "withdrawals")]
-                        withdrawals: withdrawals_ref.clone(),
-                    });
 
                     let response = engine
                         .notify_forkchoice_updated(
                             fork_choice_state,
-                            Some(payload_attributes),
+                            Some(payload_attributes.clone()),
                             self.log(),
                         )
                         .await?;
@@ -963,9 +1037,9 @@ impl<T: EthSpec> ExecutionLayer<T> {
                             debug!(
                                 self.log(),
                                 "Issuing engine_getBlobsBundle";
-                                "suggested_fee_recipient" => ?suggested_fee_recipient,
-                                "prev_randao" => ?prev_randao,
-                                "timestamp" => timestamp,
+                                "suggested_fee_recipient" => ?payload_attributes.suggested_fee_recipient(),
+                                "prev_randao" => ?payload_attributes.prev_randao(),
+                                "timestamp" => payload_attributes.timestamp(),
                                 "parent_hash" => ?parent_hash,
                             );
                             Some(engine.api.get_blobs_bundle_v1::<T>(payload_id).await)
@@ -976,16 +1050,16 @@ impl<T: EthSpec> ExecutionLayer<T> {
                     debug!(
                         self.log(),
                         "Issuing engine_getPayload";
-                        "suggested_fee_recipient" => ?suggested_fee_recipient,
-                        "prev_randao" => ?prev_randao,
-                        "timestamp" => timestamp,
+                        "suggested_fee_recipient" => ?payload_attributes.suggested_fee_recipient(),
+                        "prev_randao" => ?payload_attributes.prev_randao(),
+                        "timestamp" => payload_attributes.timestamp(),
                         "parent_hash" => ?parent_hash,
                     );
                     engine.api.get_payload::<T>(current_fork, payload_id).await
                 };
                 let (blob, payload) = tokio::join!(blob_fut, payload_fut);
                 let payload = payload.map(|full_payload| {
-                    if full_payload.fee_recipient() != suggested_fee_recipient {
+                    if full_payload.fee_recipient() != payload_attributes.suggested_fee_recipient() {
                         error!(
                             self.log(),
                             "Inconsistent fee recipient";
@@ -995,7 +1069,7 @@ impl<T: EthSpec> ExecutionLayer<T> {
                             ensure that the value of suggested_fee_recipient is set correctly and \
                             that the Execution Engine is trusted.",
                             "fee_recipient" => ?full_payload.fee_recipient(),
-                            "suggested_fee_recipient" => ?suggested_fee_recipient,
+                            "suggested_fee_recipient" => ?payload_attributes.suggested_fee_recipient(),
                         );
                     }
                     if f(self, &full_payload).is_some() {
@@ -1597,18 +1671,223 @@ impl<T: EthSpec> ExecutionLayer<T> {
             "Sending block to builder";
             "root" => ?block_root,
         );
+
         if let Some(builder) = self.builder() {
-            builder
-                .post_builder_blinded_blocks(block)
-                .await
-                .map_err(Error::Builder)
-                .map(|d| d.data)
+            let (payload_result, duration) =
+                timed_future(metrics::POST_BLINDED_PAYLOAD_BUILDER, async {
+                    builder
+                        .post_builder_blinded_blocks(block)
+                        .await
+                        .map_err(Error::Builder)
+                        .map(|d| d.data)
+                })
+                .await;
+
+            match &payload_result {
+                Ok(payload) => {
+                    metrics::inc_counter_vec(
+                        &metrics::EXECUTION_LAYER_BUILDER_REVEAL_PAYLOAD_OUTCOME,
+                        &[metrics::SUCCESS],
+                    );
+                    info!(
+                        self.log(),
+                        "Builder successfully revealed payload";
+                        "relay_response_ms" => duration.as_millis(),
+                        "block_root" => ?block_root,
+                        "fee_recipient" => ?payload.fee_recipient(),
+                        "block_hash" => ?payload.block_hash(),
+                        "parent_hash" => ?payload.parent_hash()
+                    )
+                }
+                Err(e) => {
+                    metrics::inc_counter_vec(
+                        &metrics::EXECUTION_LAYER_BUILDER_REVEAL_PAYLOAD_OUTCOME,
+                        &[metrics::FAILURE],
+                    );
+                    crit!(
+                        self.log(),
+                        "Builder failed to reveal payload";
+                        "info" => "this relay failure may cause a missed proposal",
+                        "error" => ?e,
+                        "relay_response_ms" => duration.as_millis(),
+                        "block_root" => ?block_root,
+                        "parent_hash" => ?block
+                            .message()
+                            .execution_payload()
+                            .map(|payload| format!("{}", payload.parent_hash()))
+                            .unwrap_or_else(|_| "unknown".to_string())
+                    )
+                }
+            }
+
+            payload_result
         } else {
             Err(Error::NoPayloadBuilder)
         }
     }
 }
 
+#[derive(AsRefStr)]
+#[strum(serialize_all = "snake_case")]
+enum InvalidBuilderPayload {
+    LowValue {
+        profit_threshold: Uint256,
+        payload_value: Uint256,
+    },
+    ParentHash {
+        payload: ExecutionBlockHash,
+        expected: ExecutionBlockHash,
+    },
+    PrevRandao {
+        payload: Hash256,
+        expected: Hash256,
+    },
+    Timestamp {
+        payload: u64,
+        expected: u64,
+    },
+    BlockNumber {
+        payload: u64,
+        expected: Option<u64>,
+    },
+    Fork {
+        payload: Option<ForkName>,
+        expected: ForkName,
+    },
+    Signature {
+        signature: Signature,
+        pubkey: PublicKeyBytes,
+    },
+}
+
+impl InvalidBuilderPayload {
+    /// Returns `true` if a payload is objectively invalid and should never be included on chain.
+    fn payload_invalid(&self) -> bool {
+        match self {
+            // A low-value payload isn't invalid, it should just be avoided if possible.
+            InvalidBuilderPayload::LowValue { .. } => false,
+            InvalidBuilderPayload::ParentHash { .. } => true,
+            InvalidBuilderPayload::PrevRandao { .. } => true,
+            InvalidBuilderPayload::Timestamp { .. } => true,
+            InvalidBuilderPayload::BlockNumber { .. } => true,
+            InvalidBuilderPayload::Fork { .. } => true,
+            InvalidBuilderPayload::Signature { .. } => true,
+        }
+    }
+}
+
+impl fmt::Display for InvalidBuilderPayload {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match self {
+            InvalidBuilderPayload::LowValue {
+                profit_threshold,
+                payload_value,
+            } => write!(
+                f,
+                "payload value of {} does not meet user-configured profit-threshold of {}",
+                payload_value, profit_threshold
+            ),
+            InvalidBuilderPayload::ParentHash { payload, expected } => {
+                write!(f, "payload block hash was {} not {}", payload, expected)
+            }
+            InvalidBuilderPayload::PrevRandao { payload, expected } => {
+                write!(f, "payload prev randao was {} not {}", payload, expected)
+            }
+            InvalidBuilderPayload::Timestamp { payload, expected } => {
+                write!(f, "payload timestamp was {} not {}", payload, expected)
+            }
+            InvalidBuilderPayload::BlockNumber { payload, expected } => {
+                write!(f, "payload block number was {} not {:?}", payload, expected)
+            }
+            InvalidBuilderPayload::Fork { payload, expected } => {
+                write!(f, "payload fork was {:?} not {}", payload, expected)
+            }
+            InvalidBuilderPayload::Signature { signature, pubkey } => write!(
+                f,
+                "invalid payload signature {} for pubkey {}",
+                signature, pubkey
+            ),
+        }
+    }
+}
+
+/// Perform some cursory, non-exhaustive validation of the bid returned from the builder.
+fn verify_builder_bid<T: EthSpec, Payload: AbstractExecPayload<T>>(
+    bid: &ForkVersionedResponse<SignedBuilderBid<T, Payload>>,
+    parent_hash: ExecutionBlockHash,
+    prev_randao: Hash256,
+    timestamp: u64,
+    block_number: Option<u64>,
+    profit_threshold: Uint256,
+    spec: &ChainSpec,
+) -> Result<(), Box<InvalidBuilderPayload>> {
+    let is_signature_valid = bid.data.verify_signature(spec);
+    let header = &bid.data.message.header;
+    let payload_value = bid.data.message.value;
+
+    // Avoid logging values that we can't represent with our Prometheus library.
+    let payload_value_gwei = bid.data.message.value / 1_000_000_000;
+    if payload_value_gwei <= Uint256::from(i64::max_value()) {
+        metrics::set_gauge_vec(
+            &metrics::EXECUTION_LAYER_PAYLOAD_BIDS,
+            &[metrics::BUILDER],
+            payload_value_gwei.low_u64() as i64,
+        );
+    }
+
+    if payload_value < profit_threshold {
+        Err(Box::new(InvalidBuilderPayload::LowValue {
+            profit_threshold,
+            payload_value,
+        }))
+    } else if header.parent_hash() != parent_hash {
+        Err(Box::new(InvalidBuilderPayload::ParentHash {
+            payload: header.parent_hash(),
+            expected: parent_hash,
+        }))
+    } else if header.prev_randao() != prev_randao {
+        Err(Box::new(InvalidBuilderPayload::PrevRandao {
+            payload: header.prev_randao(),
+            expected: prev_randao,
+        }))
+    } else if header.timestamp() != timestamp {
+        Err(Box::new(InvalidBuilderPayload::Timestamp {
+            payload: header.timestamp(),
+            expected: timestamp,
+        }))
+    } else if block_number.map_or(false, |n| n != header.block_number()) {
+        Err(Box::new(InvalidBuilderPayload::BlockNumber {
+            payload: header.block_number(),
+            expected: block_number,
+        }))
+    } else if !matches!(bid.version, Some(ForkName::Merge)) {
+        // Once fork information is added to the payload, we will need to
+        // check that the local and relay payloads match. At this point, if
+        // we are requesting a payload at all, we have to assume this is
+        // the Bellatrix fork.
+        Err(Box::new(InvalidBuilderPayload::Fork {
+            payload: bid.version,
+            expected: ForkName::Merge,
+        }))
+    } else if !is_signature_valid {
+        Err(Box::new(InvalidBuilderPayload::Signature {
+            signature: bid.data.signature.clone(),
+            pubkey: bid.data.message.pubkey,
+        }))
+    } else {
+        Ok(())
+    }
+}
+
+/// A helper function to record the time it takes to execute a future.
+async fn timed_future<F: Future<Output = T>, T>(metric: &str, future: F) -> (T, Duration) {
+    let start = Instant::now();
+    let result = future.await;
+    let duration = start.elapsed();
+    metrics::observe_timer_vec(&metrics::EXECUTION_LAYER_REQUEST_TIMES, &[metric], duration);
+    (result, duration)
+}
+
 #[cfg(test)]
 mod test {
     use super::*;
diff --git a/beacon_node/execution_layer/src/metrics.rs b/beacon_node/execution_layer/src/metrics.rs
index 9b00193a4..bb5a1088d 100644
--- a/beacon_node/execution_layer/src/metrics.rs
+++ b/beacon_node/execution_layer/src/metrics.rs
@@ -4,10 +4,17 @@ pub const HIT: &str = "hit";
 pub const MISS: &str = "miss";
 pub const GET_PAYLOAD: &str = "get_payload";
 pub const GET_BLINDED_PAYLOAD: &str = "get_blinded_payload";
+pub const GET_BLINDED_PAYLOAD_LOCAL: &str = "get_blinded_payload_local";
+pub const GET_BLINDED_PAYLOAD_BUILDER: &str = "get_blinded_payload_builder";
+pub const POST_BLINDED_PAYLOAD_BUILDER: &str = "post_blinded_payload_builder";
 pub const NEW_PAYLOAD: &str = "new_payload";
 pub const FORKCHOICE_UPDATED: &str = "forkchoice_updated";
 pub const GET_TERMINAL_POW_BLOCK_HASH: &str = "get_terminal_pow_block_hash";
 pub const IS_VALID_TERMINAL_POW_BLOCK_HASH: &str = "is_valid_terminal_pow_block_hash";
+pub const LOCAL: &str = "local";
+pub const BUILDER: &str = "builder";
+pub const SUCCESS: &str = "success";
+pub const FAILURE: &str = "failure";
 
 lazy_static::lazy_static! {
     pub static ref EXECUTION_LAYER_PROPOSER_INSERTED: Result<IntCounter> = try_create_int_counter(
@@ -18,9 +25,11 @@ lazy_static::lazy_static! {
         "execution_layer_proposer_data_updated",
         "Count of times new proposer data is supplied",
     );
-    pub static ref EXECUTION_LAYER_REQUEST_TIMES: Result<HistogramVec> = try_create_histogram_vec(
+    pub static ref EXECUTION_LAYER_REQUEST_TIMES: Result<HistogramVec> =
+        try_create_histogram_vec_with_buckets(
         "execution_layer_request_times",
         "Duration of calls to ELs",
+        decimal_buckets(-2, 1),
         &["method"]
     );
     pub static ref EXECUTION_LAYER_PAYLOAD_ATTRIBUTES_LOOKAHEAD: Result<Histogram> = try_create_histogram(
@@ -41,4 +50,29 @@ lazy_static::lazy_static! {
         "Indicates the payload status returned for a particular method",
         &["method", "status"]
     );
+    pub static ref EXECUTION_LAYER_GET_PAYLOAD_OUTCOME: Result<IntCounterVec> = try_create_int_counter_vec(
+        "execution_layer_get_payload_outcome",
+        "The success/failure outcomes from calling get_payload",
+        &["outcome"]
+    );
+    pub static ref EXECUTION_LAYER_BUILDER_REVEAL_PAYLOAD_OUTCOME: Result<IntCounterVec> = try_create_int_counter_vec(
+        "execution_layer_builder_reveal_payload_outcome",
+        "The success/failure outcomes from a builder un-blinding a payload",
+        &["outcome"]
+    );
+    pub static ref EXECUTION_LAYER_GET_PAYLOAD_SOURCE: Result<IntCounterVec> = try_create_int_counter_vec(
+        "execution_layer_get_payload_source",
+        "The source of each payload returned from get_payload",
+        &["source"]
+    );
+    pub static ref EXECUTION_LAYER_GET_PAYLOAD_BUILDER_REJECTIONS: Result<IntCounterVec> = try_create_int_counter_vec(
+        "execution_layer_get_payload_builder_rejections",
+        "The reasons why a payload from a builder was rejected",
+        &["reason"]
+    );
+    pub static ref EXECUTION_LAYER_PAYLOAD_BIDS: Result<IntGaugeVec> = try_create_int_gauge_vec(
+        "execution_layer_payload_bids",
+        "The gwei bid value of payloads received by local EEs or builders. Only shows values up to i64::max_value.",
+        &["source"]
+    );
 }
diff --git a/beacon_node/execution_layer/src/test_utils/mock_builder.rs b/beacon_node/execution_layer/src/test_utils/mock_builder.rs
index 5c69fffbf..06b5e81eb 100644
--- a/beacon_node/execution_layer/src/test_utils/mock_builder.rs
+++ b/beacon_node/execution_layer/src/test_utils/mock_builder.rs
@@ -1,5 +1,5 @@
 use crate::test_utils::DEFAULT_JWT_SECRET;
-use crate::{Config, ExecutionLayer, PayloadAttributes, PayloadAttributesV1};
+use crate::{Config, ExecutionLayer, PayloadAttributes};
 use async_trait::async_trait;
 use eth2::types::{BlockId, StateId, ValidatorId};
 use eth2::{BeaconNodeHttpClient, Timeouts};
@@ -289,11 +289,8 @@ impl<E: EthSpec> mev_build_rs::BlindedBlockProvider for MockBuilder<E> {
             .map_err(convert_err)?;
 
         // FIXME: think about proper fork here
-        let payload_attributes = PayloadAttributes::V1(PayloadAttributesV1 {
-            timestamp,
-            prev_randao: *prev_randao,
-            suggested_fee_recipient: fee_recipient,
-        });
+        let payload_attributes =
+            PayloadAttributes::new(timestamp, *prev_randao, fee_recipient, None);
 
         self.el
             .insert_proposer(slot, head_block_root, val_index, payload_attributes)
@@ -306,18 +303,17 @@ impl<E: EthSpec> mev_build_rs::BlindedBlockProvider for MockBuilder<E> {
             finalized_hash: Some(finalized_execution_hash),
         };
 
+        let payload_attributes =
+            PayloadAttributes::new(timestamp, *prev_randao, fee_recipient, None);
+
         let payload = self
             .el
             .get_full_payload_caching::<BlindedPayload<E>>(
                 head_execution_hash,
-                timestamp,
-                *prev_randao,
-                fee_recipient,
+                &payload_attributes,
                 forkchoice_update_params,
                 // TODO: do we need to write a test for this if this is Capella fork?
                 ForkName::Merge,
-                #[cfg(feature = "withdrawals")]
-                None,
             )
             .await
             .map_err(convert_err)?
diff --git a/beacon_node/execution_layer/src/test_utils/mock_execution_layer.rs b/beacon_node/execution_layer/src/test_utils/mock_execution_layer.rs
index cadeec1b3..e6da676a8 100644
--- a/beacon_node/execution_layer/src/test_utils/mock_execution_layer.rs
+++ b/beacon_node/execution_layer/src/test_utils/mock_execution_layer.rs
@@ -98,33 +98,16 @@ impl<T: EthSpec> MockExecutionLayer<T> {
             justified_hash: None,
             finalized_hash: None,
         };
-
-        // FIXME: this is just best guess for how to deal with forks here..
-        let payload_attributes = match &latest_execution_block {
-            &Block::PoS(ref pos_block) => match pos_block {
-                &ExecutionPayload::Merge(_) => PayloadAttributes::V1(PayloadAttributesV1 {
-                    timestamp,
-                    prev_randao,
-                    suggested_fee_recipient: Address::repeat_byte(42),
-                }),
-                &ExecutionPayload::Capella(_) | &ExecutionPayload::Eip4844(_) => {
-                    PayloadAttributes::V2(PayloadAttributesV2 {
-                        timestamp,
-                        prev_randao,
-                        suggested_fee_recipient: Address::repeat_byte(42),
-                        // FIXME: think about adding withdrawals here..
-                        #[cfg(feature = "withdrawals")]
-                        withdrawals: Some(vec![]),
-                    })
-                }
-            },
-            // I guess a PoW blocks means we should use Merge?
-            &Block::PoW(_) => PayloadAttributes::V1(PayloadAttributesV1 {
-                timestamp,
-                prev_randao,
-                suggested_fee_recipient: Address::repeat_byte(42),
-            }),
-        };
+        let payload_attributes = PayloadAttributes::new(
+            timestamp,
+            prev_randao,
+            Address::repeat_byte(42),
+            // FIXME: think about how to handle different forks / withdrawals here..
+            #[cfg(feature = "withdrawals")]
+            Some(vec![]),
+            #[cfg(not(feature = "withdrawals"))]
+            None,
+        );
 
         // Insert a proposer to ensure the fork choice updated command works.
         let slot = Slot::new(0);
@@ -150,19 +133,18 @@ impl<T: EthSpec> MockExecutionLayer<T> {
             slot,
             chain_health: ChainHealth::Healthy,
         };
+        let suggested_fee_recipient = self.el.get_suggested_fee_recipient(validator_index).await;
+        let payload_attributes =
+            PayloadAttributes::new(timestamp, prev_randao, suggested_fee_recipient, None);
         let payload: ExecutionPayload<T> = self
             .el
             .get_payload::<FullPayload<T>>(
                 parent_hash,
-                timestamp,
-                prev_randao,
-                validator_index,
+                &payload_attributes,
                 forkchoice_update_params,
                 builder_params,
                 // FIXME: do we need to consider other forks somehow? What about withdrawals?
                 ForkName::Merge,
-                #[cfg(feature = "withdrawals")]
-                Some(vec![]),
                 &self.spec,
             )
             .await
@@ -186,19 +168,18 @@ impl<T: EthSpec> MockExecutionLayer<T> {
             slot,
             chain_health: ChainHealth::Healthy,
         };
+        let suggested_fee_recipient = self.el.get_suggested_fee_recipient(validator_index).await;
+        let payload_attributes =
+            PayloadAttributes::new(timestamp, prev_randao, suggested_fee_recipient, None);
         let payload_header = self
             .el
             .get_payload::<BlindedPayload<T>>(
                 parent_hash,
-                timestamp,
-                prev_randao,
-                validator_index,
+                &payload_attributes,
                 forkchoice_update_params,
                 builder_params,
                 // FIXME: do we need to consider other forks somehow? What about withdrawals?
                 ForkName::Merge,
-                #[cfg(feature = "withdrawals")]
-                Some(vec![]),
                 &self.spec,
             )
             .await
diff --git a/beacon_node/genesis/tests/tests.rs b/beacon_node/genesis/tests/tests.rs
index 58f28702b..aaf6a7bea 100644
--- a/beacon_node/genesis/tests/tests.rs
+++ b/beacon_node/genesis/tests/tests.rs
@@ -24,7 +24,7 @@ pub fn new_env() -> Environment<MinimalEthSpec> {
 
 #[test]
 fn basic() {
-    let mut env = new_env();
+    let env = new_env();
     let log = env.core_context().log().clone();
     let mut spec = env.eth2_config().spec.clone();
 
diff --git a/beacon_node/http_api/Cargo.toml b/beacon_node/http_api/Cargo.toml
index cfd572083..e8a97fd0b 100644
--- a/beacon_node/http_api/Cargo.toml
+++ b/beacon_node/http_api/Cargo.toml
@@ -36,6 +36,9 @@ safe_arith = {path = "../../consensus/safe_arith"}
 task_executor = { path = "../../common/task_executor" }
 lru = "0.7.7"
 tree_hash = "0.4.1"
+sysinfo = "0.26.5"
+system_health = { path = "../../common/system_health" }
+directory = { path = "../../common/directory" }
 
 [dev-dependencies]
 store = { path = "../store" }
diff --git a/beacon_node/http_api/src/lib.rs b/beacon_node/http_api/src/lib.rs
index e5e8a543b..d313fcc2b 100644
--- a/beacon_node/http_api/src/lib.rs
+++ b/beacon_node/http_api/src/lib.rs
@@ -26,12 +26,14 @@ use beacon_chain::{
     BeaconChainTypes, ProduceBlockVerification, WhenSlotSkipped,
 };
 pub use block_id::BlockId;
+use directory::DEFAULT_ROOT_DIR;
 use eth2::types::{
     self as api_types, EndpointVersion, SkipRandaoVerification, ValidatorId, ValidatorStatus,
 };
 use lighthouse_network::{types::SyncState, EnrExt, NetworkGlobals, PeerId, PubsubMessage};
 use lighthouse_version::version_with_platform;
 use network::{NetworkMessage, NetworkSenders, ValidatorSubscriptionMessage};
+use parking_lot::RwLock;
 use serde::{Deserialize, Serialize};
 use slog::{crit, debug, error, info, warn, Logger};
 use slot_clock::SlotClock;
@@ -43,6 +45,8 @@ use std::net::{IpAddr, Ipv4Addr, SocketAddr};
 use std::path::PathBuf;
 use std::pin::Pin;
 use std::sync::Arc;
+use sysinfo::{System, SystemExt};
+use system_health::observe_system_health_bn;
 use tokio::sync::mpsc::{Sender, UnboundedSender};
 use tokio_stream::{wrappers::BroadcastStream, StreamExt};
 use types::{
@@ -110,6 +114,7 @@ pub struct Config {
     pub tls_config: Option<TlsConfig>,
     pub allow_sync_stalled: bool,
     pub spec_fork_name: Option<ForkName>,
+    pub data_dir: PathBuf,
 }
 
 impl Default for Config {
@@ -122,6 +127,7 @@ impl Default for Config {
             tls_config: None,
             allow_sync_stalled: false,
             spec_fork_name: None,
+            data_dir: PathBuf::from(DEFAULT_ROOT_DIR),
         }
     }
 }
@@ -323,6 +329,10 @@ pub fn serve<T: BeaconChainTypes>(
             }
         });
 
+    // Create a `warp` filter for the data_dir.
+    let inner_data_dir = ctx.config.data_dir.clone();
+    let data_dir_filter = warp::any().map(move || inner_data_dir.clone());
+
     // Create a `warp` filter that provides access to the beacon chain.
     let inner_ctx = ctx.clone();
     let chain_filter =
@@ -431,6 +441,37 @@ pub fn serve<T: BeaconChainTypes>(
     let inner_ctx = ctx.clone();
     let log_filter = warp::any().map(move || inner_ctx.log.clone());
 
+    // Create a `warp` filter that provides access to local system information.
+    let system_info = Arc::new(RwLock::new(sysinfo::System::new()));
+    {
+        // grab write access for initialisation
+        let mut system_info = system_info.write();
+        system_info.refresh_disks_list();
+        system_info.refresh_networks_list();
+        system_info.refresh_cpu_specifics(sysinfo::CpuRefreshKind::everything());
+        system_info.refresh_cpu();
+    } // end lock
+
+    let system_info_filter =
+        warp::any()
+            .map(move || system_info.clone())
+            .map(|sysinfo: Arc<RwLock<System>>| {
+                {
+                    // refresh stats
+                    let mut sysinfo_lock = sysinfo.write();
+                    sysinfo_lock.refresh_memory();
+                    sysinfo_lock.refresh_cpu_specifics(sysinfo::CpuRefreshKind::everything());
+                    sysinfo_lock.refresh_cpu();
+                    sysinfo_lock.refresh_system();
+                    sysinfo_lock.refresh_networks();
+                    sysinfo_lock.refresh_disks();
+                } // end lock
+                sysinfo
+            });
+
+    let app_start = std::time::Instant::now();
+    let app_start_filter = warp::any().map(move || app_start);
+
     /*
      *
      * Start of HTTP method definitions.
@@ -891,6 +932,37 @@ pub fn serve<T: BeaconChainTypes>(
             },
         );
 
+    // GET beacon/states/{state_id}/randao?epoch
+    let get_beacon_state_randao = beacon_states_path
+        .clone()
+        .and(warp::path("randao"))
+        .and(warp::query::<api_types::RandaoQuery>())
+        .and(warp::path::end())
+        .and_then(
+            |state_id: StateId, chain: Arc<BeaconChain<T>>, query: api_types::RandaoQuery| {
+                blocking_json_task(move || {
+                    let (randao, execution_optimistic) = state_id
+                        .map_state_and_execution_optimistic(
+                            &chain,
+                            |state, execution_optimistic| {
+                                let epoch = query.epoch.unwrap_or_else(|| state.current_epoch());
+                                let randao = *state.get_randao_mix(epoch).map_err(|e| {
+                                    warp_utils::reject::custom_bad_request(format!(
+                                        "epoch out of range: {e:?}"
+                                    ))
+                                })?;
+                                Ok((randao, execution_optimistic))
+                            },
+                        )?;
+
+                    Ok(
+                        api_types::GenericResponse::from(api_types::RandaoMix { randao })
+                            .add_execution_optimistic(execution_optimistic),
+                    )
+                })
+            },
+        );
+
     // GET beacon/headers
     //
     // Note: this endpoint only returns information about blocks in the canonical chain. Given that
@@ -1168,6 +1240,51 @@ pub fn serve<T: BeaconChainTypes>(
             })
         });
 
+    // GET beacon/blinded_blocks/{block_id}
+    let get_beacon_blinded_block = eth_v1
+        .and(warp::path("beacon"))
+        .and(warp::path("blinded_blocks"))
+        .and(block_id_or_err)
+        .and(chain_filter.clone())
+        .and(warp::path::end())
+        .and(warp::header::optional::<api_types::Accept>("accept"))
+        .and_then(
+            |block_id: BlockId,
+             chain: Arc<BeaconChain<T>>,
+             accept_header: Option<api_types::Accept>| {
+                blocking_task(move || {
+                    let (block, execution_optimistic) = block_id.blinded_block(&chain)?;
+                    let fork_name = block
+                        .fork_name(&chain.spec)
+                        .map_err(inconsistent_fork_rejection)?;
+
+                    match accept_header {
+                        Some(api_types::Accept::Ssz) => Response::builder()
+                            .status(200)
+                            .header("Content-Type", "application/octet-stream")
+                            .body(block.as_ssz_bytes().into())
+                            .map_err(|e| {
+                                warp_utils::reject::custom_server_error(format!(
+                                    "failed to create response: {}",
+                                    e
+                                ))
+                            }),
+                        _ => {
+                            // Post as a V2 endpoint so we return the fork version.
+                            execution_optimistic_fork_versioned_response(
+                                V2,
+                                fork_name,
+                                execution_optimistic,
+                                block,
+                            )
+                            .map(|res| warp::reply::json(&res).into_response())
+                        }
+                    }
+                    .map(|resp| add_consensus_version_header(resp, fork_name))
+                })
+            },
+        );
+
     /*
      * beacon/pool
      */
@@ -2681,7 +2798,12 @@ pub fn serve<T: BeaconChainTypes>(
                     .await
                     .map(|resp| warp::reply::json(&resp))
                     .map_err(|e| {
-                        error!(log, "Error from connected relay"; "error" => ?e);
+                        error!(
+                            log,
+                            "Relay error when registering validator(s)";
+                            "num_registrations" => filtered_registration_data.len(),
+                            "error" => ?e
+                        );
                         // Forward the HTTP status code if we are able to, otherwise fall back
                         // to a server error.
                         if let eth2::Error::ServerMessage(message) = e {
@@ -2795,6 +2917,29 @@ pub fn serve<T: BeaconChainTypes>(
             })
         });
 
+    // GET lighthouse/ui/health
+    let get_lighthouse_ui_health = warp::path("lighthouse")
+        .and(warp::path("ui"))
+        .and(warp::path("health"))
+        .and(warp::path::end())
+        .and(system_info_filter)
+        .and(app_start_filter)
+        .and(data_dir_filter)
+        .and(network_globals.clone())
+        .and_then(
+            |sysinfo, app_start: std::time::Instant, data_dir, network_globals| {
+                blocking_json_task(move || {
+                    let app_uptime = app_start.elapsed().as_secs() as u64;
+                    Ok(api_types::GenericResponse::from(observe_system_health_bn(
+                        sysinfo,
+                        data_dir,
+                        app_uptime,
+                        network_globals,
+                    )))
+                })
+            },
+        );
+
     // GET lighthouse/syncing
     let get_lighthouse_syncing = warp::path("lighthouse")
         .and(warp::path("syncing"))
@@ -3213,10 +3358,12 @@ pub fn serve<T: BeaconChainTypes>(
                 .or(get_beacon_state_validators.boxed())
                 .or(get_beacon_state_committees.boxed())
                 .or(get_beacon_state_sync_committees.boxed())
+                .or(get_beacon_state_randao.boxed())
                 .or(get_beacon_headers.boxed())
                 .or(get_beacon_headers_block_id.boxed())
                 .or(get_beacon_block.boxed())
                 .or(get_beacon_block_attestations.boxed())
+                .or(get_beacon_blinded_block.boxed())
                 .or(get_beacon_block_root.boxed())
                 .or(get_beacon_pool_attestations.boxed())
                 .or(get_beacon_pool_attester_slashings.boxed())
@@ -3243,6 +3390,7 @@ pub fn serve<T: BeaconChainTypes>(
                 .or(get_validator_aggregate_attestation.boxed())
                 .or(get_validator_sync_committee_contribution.boxed())
                 .or(get_lighthouse_health.boxed())
+                .or(get_lighthouse_ui_health.boxed())
                 .or(get_lighthouse_syncing.boxed())
                 .or(get_lighthouse_nat.boxed())
                 .or(get_lighthouse_peers.boxed())
@@ -3262,6 +3410,7 @@ pub fn serve<T: BeaconChainTypes>(
                 .or(get_lighthouse_merge_readiness.boxed())
                 .or(get_events.boxed()),
         )
+        .boxed()
         .or(warp::post().and(
             post_beacon_blocks
                 .boxed()
diff --git a/beacon_node/http_api/src/publish_blocks.rs b/beacon_node/http_api/src/publish_blocks.rs
index 5b63c460b..9b06c2bd4 100644
--- a/beacon_node/http_api/src/publish_blocks.rs
+++ b/beacon_node/http_api/src/publish_blocks.rs
@@ -1,5 +1,6 @@
 use crate::metrics;
 use beacon_chain::validator_monitor::{get_block_delay_ms, timestamp_now};
+use beacon_chain::NotifyExecutionLayer;
 use beacon_chain::{BeaconChain, BeaconChainTypes, BlockError, CountUnrealized};
 use lighthouse_network::PubsubMessage;
 use network::NetworkMessage;
@@ -53,7 +54,12 @@ pub async fn publish_block<T: BeaconChainTypes>(
     metrics::observe_duration(&metrics::HTTP_API_BLOCK_BROADCAST_DELAY_TIMES, delay);
 
     match chain
-        .process_block(block_root, block.clone(), CountUnrealized::True)
+        .process_block(
+            block_root,
+            block.clone(),
+            CountUnrealized::True,
+            NotifyExecutionLayer::Yes,
+        )
         .await
     {
         Ok(root) => {
diff --git a/beacon_node/http_api/tests/common.rs b/beacon_node/http_api/tests/common.rs
index eaf91ce9d..ec1448df7 100644
--- a/beacon_node/http_api/tests/common.rs
+++ b/beacon_node/http_api/tests/common.rs
@@ -2,6 +2,7 @@ use beacon_chain::{
     test_utils::{BeaconChainHarness, EphemeralHarnessType},
     BeaconChain, BeaconChainTypes,
 };
+use directory::DEFAULT_ROOT_DIR;
 use eth2::{BeaconNodeHttpClient, Timeouts};
 use http_api::{Config, Context};
 use lighthouse_network::{
@@ -142,6 +143,7 @@ pub async fn create_api_server_on_port<T: BeaconChainTypes>(
             allow_origin: None,
             tls_config: None,
             allow_sync_stalled: false,
+            data_dir: std::path::PathBuf::from(DEFAULT_ROOT_DIR),
             spec_fork_name: None,
         },
         chain: Some(chain.clone()),
diff --git a/beacon_node/http_api/tests/tests.rs b/beacon_node/http_api/tests/tests.rs
index ff664d6ff..2e795e522 100644
--- a/beacon_node/http_api/tests/tests.rs
+++ b/beacon_node/http_api/tests/tests.rs
@@ -745,6 +745,36 @@ impl ApiTester {
         self
     }
 
+    pub async fn test_beacon_states_randao(self) -> Self {
+        for state_id in self.interesting_state_ids() {
+            let mut state_opt = state_id
+                .state(&self.chain)
+                .ok()
+                .map(|(state, _execution_optimistic)| state);
+
+            let epoch_opt = state_opt.as_ref().map(|state| state.current_epoch());
+            let result = self
+                .client
+                .get_beacon_states_randao(state_id.0, epoch_opt)
+                .await
+                .unwrap()
+                .map(|res| res.data);
+
+            if result.is_none() && state_opt.is_none() {
+                continue;
+            }
+
+            let state = state_opt.as_mut().expect("result should be none");
+            let randao_mix = state
+                .get_randao_mix(state.slot().epoch(E::slots_per_epoch()))
+                .unwrap();
+
+            assert_eq!(result.unwrap().randao, *randao_mix);
+        }
+
+        self
+    }
+
     pub async fn test_beacon_headers_all_slots(self) -> Self {
         for slot in 0..CHAIN_LENGTH {
             let slot = Slot::from(slot);
@@ -1016,6 +1046,82 @@ impl ApiTester {
         self
     }
 
+    pub async fn test_beacon_blinded_blocks(self) -> Self {
+        for block_id in self.interesting_block_ids() {
+            let expected = block_id
+                .blinded_block(&self.chain)
+                .ok()
+                .map(|(block, _execution_optimistic)| block);
+
+            if let CoreBlockId::Slot(slot) = block_id.0 {
+                if expected.is_none() {
+                    assert!(SKIPPED_SLOTS.contains(&slot.as_u64()));
+                } else {
+                    assert!(!SKIPPED_SLOTS.contains(&slot.as_u64()));
+                }
+            }
+
+            // Check the JSON endpoint.
+            let json_result = self
+                .client
+                .get_beacon_blinded_blocks(block_id.0)
+                .await
+                .unwrap();
+
+            if let (Some(json), Some(expected)) = (&json_result, &expected) {
+                assert_eq!(&json.data, expected, "{:?}", block_id);
+                assert_eq!(
+                    json.version,
+                    Some(expected.fork_name(&self.chain.spec).unwrap())
+                );
+            } else {
+                assert_eq!(json_result, None);
+                assert_eq!(expected, None);
+            }
+
+            // Check the SSZ endpoint.
+            let ssz_result = self
+                .client
+                .get_beacon_blinded_blocks_ssz(block_id.0, &self.chain.spec)
+                .await
+                .unwrap();
+            assert_eq!(ssz_result.as_ref(), expected.as_ref(), "{:?}", block_id);
+
+            // Check that version headers are provided.
+            let url = self
+                .client
+                .get_beacon_blinded_blocks_path(block_id.0)
+                .unwrap();
+
+            let builders: Vec<fn(RequestBuilder) -> RequestBuilder> = vec![
+                |b| b,
+                |b| b.accept(Accept::Ssz),
+                |b| b.accept(Accept::Json),
+                |b| b.accept(Accept::Any),
+            ];
+
+            for req_builder in builders {
+                let raw_res = self
+                    .client
+                    .get_response(url.clone(), req_builder)
+                    .await
+                    .optional()
+                    .unwrap();
+                if let (Some(raw_res), Some(expected)) = (&raw_res, &expected) {
+                    assert_eq!(
+                        raw_res.fork_name_from_header().unwrap(),
+                        Some(expected.fork_name(&self.chain.spec).unwrap())
+                    );
+                } else {
+                    assert!(raw_res.is_none());
+                    assert_eq!(expected, None);
+                }
+            }
+        }
+
+        self
+    }
+
     pub async fn test_beacon_blocks_attestations(self) -> Self {
         for block_id in self.interesting_block_ids() {
             let result = self
@@ -3696,6 +3802,8 @@ async fn beacon_get() {
         .await
         .test_beacon_states_validator_id()
         .await
+        .test_beacon_states_randao()
+        .await
         .test_beacon_headers_all_slots()
         .await
         .test_beacon_headers_all_parents()
@@ -3704,6 +3812,8 @@ async fn beacon_get() {
         .await
         .test_beacon_blocks()
         .await
+        .test_beacon_blinded_blocks()
+        .await
         .test_beacon_blocks_attestations()
         .await
         .test_beacon_blocks_root()
diff --git a/beacon_node/lighthouse_network/src/config.rs b/beacon_node/lighthouse_network/src/config.rs
index 046167d5d..32712e32a 100644
--- a/beacon_node/lighthouse_network/src/config.rs
+++ b/beacon_node/lighthouse_network/src/config.rs
@@ -130,6 +130,9 @@ pub struct Config {
 
     /// Whether metrics are enabled.
     pub metrics_enabled: bool,
+
+    /// Whether light client protocols should be enabled.
+    pub enable_light_client_server: bool,
 }
 
 impl Default for Config {
@@ -207,6 +210,7 @@ impl Default for Config {
             shutdown_after_sync: false,
             topics: Vec::new(),
             metrics_enabled: false,
+            enable_light_client_server: false,
         }
     }
 }
@@ -284,9 +288,11 @@ impl From<u8> for NetworkLoad {
 /// Return a Lighthouse specific `GossipsubConfig` where the `message_id_fn` depends on the current fork.
 pub fn gossipsub_config(network_load: u8, fork_context: Arc<ForkContext>) -> GossipsubConfig {
     // The function used to generate a gossipsub message id
-    // We use the first 8 bytes of SHA256(data) for content addressing
-    let fast_gossip_message_id =
-        |message: &RawGossipsubMessage| FastMessageId::from(&Sha256::digest(&message.data)[..8]);
+    // We use the first 8 bytes of SHA256(topic, data) for content addressing
+    let fast_gossip_message_id = |message: &RawGossipsubMessage| {
+        let data = [message.topic.as_str().as_bytes(), &message.data].concat();
+        FastMessageId::from(&Sha256::digest(data)[..8])
+    };
     fn prefix(
         prefix: [u8; 4],
         message: &GossipsubMessage,
diff --git a/beacon_node/lighthouse_network/src/discovery/mod.rs b/beacon_node/lighthouse_network/src/discovery/mod.rs
index 3535c6bd9..8e528f09d 100644
--- a/beacon_node/lighthouse_network/src/discovery/mod.rs
+++ b/beacon_node/lighthouse_network/src/discovery/mod.rs
@@ -834,6 +834,17 @@ impl<TSpec: EthSpec> Discovery<TSpec> {
 
                         // Map each subnet query's min_ttl to the set of ENR's returned for that subnet.
                         queries.iter().for_each(|query| {
+                            let query_str = match query.subnet {
+                                Subnet::Attestation(_) => "attestation",
+                                Subnet::SyncCommittee(_) => "sync_committee",
+                            };
+
+                            if let Some(v) = metrics::get_int_counter(
+                                &metrics::TOTAL_SUBNET_QUERIES,
+                                &[query_str],
+                            ) {
+                                v.inc();
+                            }
                             // A subnet query has completed. Add back to the queue, incrementing retries.
                             self.add_subnet_query(query.subnet, query.min_ttl, query.retries + 1);
 
@@ -845,6 +856,12 @@ impl<TSpec: EthSpec> Discovery<TSpec> {
                                 .filter(|enr| subnet_predicate(enr))
                                 .map(|enr| enr.peer_id())
                                 .for_each(|peer_id| {
+                                    if let Some(v) = metrics::get_int_counter(
+                                        &metrics::SUBNET_PEERS_FOUND,
+                                        &[query_str],
+                                    ) {
+                                        v.inc();
+                                    }
                                     let other_min_ttl = mapped_results.get_mut(&peer_id);
 
                                     // map peer IDs to the min_ttl furthest in the future
diff --git a/beacon_node/lighthouse_network/src/metrics.rs b/beacon_node/lighthouse_network/src/metrics.rs
index 66d7a1f74..2ee224d5e 100644
--- a/beacon_node/lighthouse_network/src/metrics.rs
+++ b/beacon_node/lighthouse_network/src/metrics.rs
@@ -112,6 +112,19 @@ lazy_static! {
             &["client"]
         );
 
+    pub static ref SUBNET_PEERS_FOUND: Result<IntCounterVec> =
+        try_create_int_counter_vec(
+            "discovery_query_peers_found",
+            "Total number of peers found in attestation subnets and sync subnets",
+            &["type"]
+        );
+    pub static ref TOTAL_SUBNET_QUERIES: Result<IntCounterVec> =
+        try_create_int_counter_vec(
+            "discovery_total_queries",
+            "Total number of discovery subnet queries",
+            &["type"]
+        );
+
     /*
      * Inbound/Outbound peers
      */
diff --git a/beacon_node/lighthouse_network/src/peer_manager/mod.rs b/beacon_node/lighthouse_network/src/peer_manager/mod.rs
index 0ad1264d6..f85ec980d 100644
--- a/beacon_node/lighthouse_network/src/peer_manager/mod.rs
+++ b/beacon_node/lighthouse_network/src/peer_manager/mod.rs
@@ -405,7 +405,7 @@ impl<TSpec: EthSpec> PeerManager<TSpec> {
                 debug!(self.log, "Identified Peer"; "peer" => %peer_id,
                     "protocol_version" => &info.protocol_version,
                     "agent_version" => &info.agent_version,
-                    "listening_ addresses" => ?info.listen_addrs,
+                    "listening_addresses" => ?info.listen_addrs,
                     "observed_address" => ?info.observed_addr,
                     "protocols" => ?info.protocols
                 );
@@ -502,6 +502,7 @@ impl<TSpec: EthSpec> PeerManager<TSpec> {
                     Protocol::BlocksByRange => PeerAction::MidToleranceError,
                     Protocol::BlocksByRoot => PeerAction::MidToleranceError,
                     Protocol::BlobsByRange => PeerAction::MidToleranceError,
+                    Protocol::LightClientBootstrap => PeerAction::LowToleranceError,
                     Protocol::BlobsByRoot => PeerAction::MidToleranceError,
                     Protocol::Goodbye => PeerAction::LowToleranceError,
                     Protocol::MetaData => PeerAction::LowToleranceError,
@@ -521,6 +522,7 @@ impl<TSpec: EthSpec> PeerManager<TSpec> {
                     Protocol::BlobsByRange => return,
                     Protocol::BlobsByRoot => return,
                     Protocol::Goodbye => return,
+                    Protocol::LightClientBootstrap => return,
                     Protocol::MetaData => PeerAction::LowToleranceError,
                     Protocol::Status => PeerAction::LowToleranceError,
                 }
@@ -537,6 +539,7 @@ impl<TSpec: EthSpec> PeerManager<TSpec> {
                     Protocol::BlocksByRoot => PeerAction::MidToleranceError,
                     Protocol::BlobsByRange => PeerAction::MidToleranceError,
                     Protocol::BlobsByRoot => PeerAction::MidToleranceError,
+                    Protocol::LightClientBootstrap => return,
                     Protocol::Goodbye => return,
                     Protocol::MetaData => return,
                     Protocol::Status => return,
diff --git a/beacon_node/lighthouse_network/src/peer_manager/network_behaviour.rs b/beacon_node/lighthouse_network/src/peer_manager/network_behaviour.rs
index c84e368f1..175dfaf01 100644
--- a/beacon_node/lighthouse_network/src/peer_manager/network_behaviour.rs
+++ b/beacon_node/lighthouse_network/src/peer_manager/network_behaviour.rs
@@ -139,7 +139,7 @@ impl<TSpec: EthSpec> NetworkBehaviour for PeerManager<TSpec> {
             // TODO: directly emit the ban event?
             BanResult::BadScore => {
                 // This is a faulty state
-                error!(self.log, "Connected to a banned peer, re-banning"; "peer_id" => %peer_id);
+                error!(self.log, "Connected to a banned peer. Re-banning"; "peer_id" => %peer_id);
                 // Reban the peer
                 self.goodbye_peer(peer_id, GoodbyeReason::Banned, ReportSource::PeerManager);
                 return;
diff --git a/beacon_node/lighthouse_network/src/rpc/codec/ssz_snappy.rs b/beacon_node/lighthouse_network/src/rpc/codec/ssz_snappy.rs
index 4538d8389..a70aac349 100644
--- a/beacon_node/lighthouse_network/src/rpc/codec/ssz_snappy.rs
+++ b/beacon_node/lighthouse_network/src/rpc/codec/ssz_snappy.rs
@@ -15,10 +15,11 @@ use std::io::{Read, Write};
 use std::marker::PhantomData;
 use std::sync::Arc;
 use tokio_util::codec::{Decoder, Encoder};
+use types::light_client_bootstrap::LightClientBootstrap;
 use types::{
-    BlobsSidecar, EthSpec, ForkContext, ForkName, SignedBeaconBlock, SignedBeaconBlockAltair,
-    SignedBeaconBlockAndBlobsSidecar, SignedBeaconBlockBase, SignedBeaconBlockCapella,
-    SignedBeaconBlockEip4844, SignedBeaconBlockMerge,
+    BlobsSidecar, EthSpec, ForkContext, ForkName, Hash256, SignedBeaconBlock,
+    SignedBeaconBlockAltair, SignedBeaconBlockAndBlobsSidecar, SignedBeaconBlockBase,
+    SignedBeaconBlockCapella, SignedBeaconBlockEip4844, SignedBeaconBlockMerge,
 };
 use unsigned_varint::codec::Uvi;
 
@@ -73,6 +74,7 @@ impl<TSpec: EthSpec> Encoder<RPCCodedResponse<TSpec>> for SSZSnappyInboundCodec<
                 RPCResponse::BlocksByRoot(res) => res.as_ssz_bytes(),
                 RPCResponse::BlobsByRange(res) => res.as_ssz_bytes(),
                 RPCResponse::BlobsByRoot(res) => res.as_ssz_bytes(),
+                RPCResponse::LightClientBootstrap(res) => res.as_ssz_bytes(),
                 RPCResponse::Pong(res) => res.data.as_ssz_bytes(),
                 RPCResponse::MetaData(res) =>
                 // Encode the correct version of the MetaData response based on the negotiated version.
@@ -235,6 +237,7 @@ impl<TSpec: EthSpec> Encoder<OutboundRequest<TSpec>> for SSZSnappyOutboundCodec<
             OutboundRequest::BlobsByRoot(req) => req.block_roots.as_ssz_bytes(),
             OutboundRequest::Ping(req) => req.as_ssz_bytes(),
             OutboundRequest::MetaData(_) => return Ok(()), // no metadata to encode
+            OutboundRequest::LightClientBootstrap(req) => req.as_ssz_bytes(),
         };
         // SSZ encoded bytes should be within `max_packet_size`
         if bytes.len() > self.max_packet_size {
@@ -495,7 +498,11 @@ fn handle_v1_request<T: EthSpec>(
         Protocol::Ping => Ok(Some(InboundRequest::Ping(Ping {
             data: u64::from_ssz_bytes(decoded_buffer)?,
         }))),
-
+        Protocol::LightClientBootstrap => Ok(Some(InboundRequest::LightClientBootstrap(
+            LightClientBootstrapRequest {
+                root: Hash256::from_ssz_bytes(decoded_buffer)?,
+            },
+        ))),
         // MetaData requests return early from InboundUpgrade and do not reach the decoder.
         // Handle this case just for completeness.
         Protocol::MetaData => {
@@ -605,6 +612,9 @@ fn handle_v1_response<T: EthSpec>(
         Protocol::MetaData => Ok(Some(RPCResponse::MetaData(MetaData::V1(
             MetaDataV1::from_ssz_bytes(decoded_buffer)?,
         )))),
+        Protocol::LightClientBootstrap => Ok(Some(RPCResponse::LightClientBootstrap(
+            LightClientBootstrap::from_ssz_bytes(decoded_buffer)?,
+        ))),
     }
 }
 
@@ -966,6 +976,9 @@ mod tests {
                 OutboundRequest::MetaData(metadata) => {
                     assert_eq!(decoded, InboundRequest::MetaData(metadata))
                 }
+                OutboundRequest::LightClientBootstrap(bootstrap) => {
+                    assert_eq!(decoded, InboundRequest::LightClientBootstrap(bootstrap))
+                }
             }
         }
     }
diff --git a/beacon_node/lighthouse_network/src/rpc/handler.rs b/beacon_node/lighthouse_network/src/rpc/handler.rs
index 9ac062adc..9d6229eb3 100644
--- a/beacon_node/lighthouse_network/src/rpc/handler.rs
+++ b/beacon_node/lighthouse_network/src/rpc/handler.rs
@@ -285,7 +285,7 @@ where
         } else {
             if !matches!(response, RPCCodedResponse::StreamTermination(..)) {
                 // the stream is closed after sending the expected number of responses
-                trace!(self.log, "Inbound stream has expired, response not sent";
+                trace!(self.log, "Inbound stream has expired. Response not sent";
                     "response" => %response, "id" => inbound_id);
             }
             return;
diff --git a/beacon_node/lighthouse_network/src/rpc/methods.rs b/beacon_node/lighthouse_network/src/rpc/methods.rs
index 1f9df0a0b..7b7786aa0 100644
--- a/beacon_node/lighthouse_network/src/rpc/methods.rs
+++ b/beacon_node/lighthouse_network/src/rpc/methods.rs
@@ -12,9 +12,11 @@ use std::ops::Deref;
 use std::sync::Arc;
 use strum::IntoStaticStr;
 use superstruct::superstruct;
-use types::blobs_sidecar::BlobsSidecar;
 use types::SignedBeaconBlockAndBlobsSidecar;
-use types::{Epoch, EthSpec, Hash256, SignedBeaconBlock, Slot};
+use types::{
+    blobs_sidecar::BlobsSidecar, light_client_bootstrap::LightClientBootstrap, Epoch, EthSpec,
+    Hash256, SignedBeaconBlock, Slot,
+};
 
 /// Maximum number of blocks in a single request.
 pub type MaxRequestBlocks = U1024;
@@ -268,6 +270,9 @@ pub enum RPCResponse<T: EthSpec> {
     /// A response to a get BLOBS_BY_RANGE request
     BlobsByRange(Arc<BlobsSidecar<T>>),
 
+    /// A response to a get LIGHTCLIENT_BOOTSTRAP request.
+    LightClientBootstrap(LightClientBootstrap<T>),
+
     /// A response to a get BLOBS_BY_ROOT request.
     BlobsByRoot(Arc<SignedBeaconBlockAndBlobsSidecar<T>>),
 
@@ -307,6 +312,12 @@ pub enum RPCCodedResponse<T: EthSpec> {
     StreamTermination(ResponseTermination),
 }
 
+/// Request a light_client_bootstrap for lightclients peers.
+#[derive(Encode, Decode, Clone, Debug, PartialEq)]
+pub struct LightClientBootstrapRequest {
+    pub root: Hash256,
+}
+
 /// The code assigned to an erroneous `RPCResponse`.
 #[derive(Debug, Clone, Copy, PartialEq, IntoStaticStr)]
 #[strum(serialize_all = "snake_case")]
@@ -357,6 +368,7 @@ impl<T: EthSpec> RPCCodedResponse<T> {
                 RPCResponse::BlobsByRoot(_) => true,
                 RPCResponse::Pong(_) => false,
                 RPCResponse::MetaData(_) => false,
+                RPCResponse::LightClientBootstrap(_) => false,
             },
             RPCCodedResponse::Error(_, _) => true,
             // Stream terminations are part of responses that have chunks
@@ -393,6 +405,7 @@ impl<T: EthSpec> RPCResponse<T> {
             RPCResponse::BlobsByRoot(_) => Protocol::BlobsByRoot,
             RPCResponse::Pong(_) => Protocol::Ping,
             RPCResponse::MetaData(_) => Protocol::MetaData,
+            RPCResponse::LightClientBootstrap(_) => Protocol::LightClientBootstrap,
         }
     }
 }
@@ -438,6 +451,9 @@ impl<T: EthSpec> std::fmt::Display for RPCResponse<T> {
             }
             RPCResponse::Pong(ping) => write!(f, "Pong: {}", ping.data),
             RPCResponse::MetaData(metadata) => write!(f, "Metadata: {}", metadata.seq_number()),
+            RPCResponse::LightClientBootstrap(bootstrap) => {
+                write!(f, "LightClientBootstrap Slot: {}", bootstrap.header.slot)
+            }
         }
     }
 }
diff --git a/beacon_node/lighthouse_network/src/rpc/mod.rs b/beacon_node/lighthouse_network/src/rpc/mod.rs
index ca41fb2bd..9d2aeb0eb 100644
--- a/beacon_node/lighthouse_network/src/rpc/mod.rs
+++ b/beacon_node/lighthouse_network/src/rpc/mod.rs
@@ -27,8 +27,8 @@ pub(crate) use protocol::{InboundRequest, RPCProtocol};
 use crate::rpc::methods::MAX_REQUEST_BLOBS_SIDECARS;
 pub use handler::SubstreamId;
 pub use methods::{
-    BlocksByRangeRequest, BlocksByRootRequest, GoodbyeReason, MaxRequestBlocks,
-    RPCResponseErrorCode, ResponseTermination, StatusMessage, MAX_REQUEST_BLOCKS,
+    BlocksByRangeRequest, BlocksByRootRequest, GoodbyeReason, LightClientBootstrapRequest,
+    MaxRequestBlocks, RPCResponseErrorCode, ResponseTermination, StatusMessage, MAX_REQUEST_BLOCKS,
 };
 pub(crate) use outbound::OutboundRequest;
 pub use protocol::{max_rpc_size, Protocol, RPCError};
@@ -109,18 +109,24 @@ pub struct RPC<Id: ReqId, TSpec: EthSpec> {
     /// Queue of events to be processed.
     events: Vec<NetworkBehaviourAction<RPCMessage<Id, TSpec>, RPCHandler<Id, TSpec>>>,
     fork_context: Arc<ForkContext>,
+    enable_light_client_server: bool,
     /// Slog logger for RPC behaviour.
     log: slog::Logger,
 }
 
 impl<Id: ReqId, TSpec: EthSpec> RPC<Id, TSpec> {
-    pub fn new(fork_context: Arc<ForkContext>, log: slog::Logger) -> Self {
+    pub fn new(
+        fork_context: Arc<ForkContext>,
+        enable_light_client_server: bool,
+        log: slog::Logger,
+    ) -> Self {
         let log = log.new(o!("service" => "libp2p_rpc"));
         let limiter = RPCRateLimiterBuilder::new()
             .n_every(Protocol::MetaData, 2, Duration::from_secs(5))
             .n_every(Protocol::Ping, 2, Duration::from_secs(10))
             .n_every(Protocol::Status, 5, Duration::from_secs(15))
             .one_every(Protocol::Goodbye, Duration::from_secs(10))
+            .one_every(Protocol::LightClientBootstrap, Duration::from_secs(10))
             .n_every(
                 Protocol::BlocksByRange,
                 methods::MAX_REQUEST_BLOCKS,
@@ -139,6 +145,7 @@ impl<Id: ReqId, TSpec: EthSpec> RPC<Id, TSpec> {
             limiter,
             events: Vec::new(),
             fork_context,
+            enable_light_client_server,
             log,
         }
     }
@@ -195,6 +202,7 @@ where
                 RPCProtocol {
                     fork_context: self.fork_context.clone(),
                     max_rpc_size: max_rpc_size(&self.fork_context),
+                    enable_light_client_server: self.enable_light_client_server,
                     phantom: PhantomData,
                 },
                 (),
diff --git a/beacon_node/lighthouse_network/src/rpc/outbound.rs b/beacon_node/lighthouse_network/src/rpc/outbound.rs
index 8d301fdc1..090db77ec 100644
--- a/beacon_node/lighthouse_network/src/rpc/outbound.rs
+++ b/beacon_node/lighthouse_network/src/rpc/outbound.rs
@@ -40,6 +40,7 @@ pub enum OutboundRequest<TSpec: EthSpec> {
     BlocksByRoot(BlocksByRootRequest),
     BlobsByRange(BlobsByRangeRequest),
     BlobsByRoot(BlobsByRootRequest),
+    LightClientBootstrap(LightClientBootstrapRequest),
     Ping(Ping),
     MetaData(PhantomData<TSpec>),
 }
@@ -96,9 +97,12 @@ impl<TSpec: EthSpec> OutboundRequest<TSpec> {
                 ProtocolId::new(Protocol::MetaData, Version::V2, Encoding::SSZSnappy),
                 ProtocolId::new(Protocol::MetaData, Version::V1, Encoding::SSZSnappy),
             ],
+            // Note: This match arm is technically unreachable as we only respond to light client requests
+            // that we generate from the beacon state.
+            // We do not make light client rpc requests from the beacon node
+            OutboundRequest::LightClientBootstrap(_) => vec![],
         }
     }
-
     /* These functions are used in the handler for stream management */
 
     /// Number of responses expected for this request.
@@ -112,6 +116,7 @@ impl<TSpec: EthSpec> OutboundRequest<TSpec> {
             OutboundRequest::BlobsByRoot(req) => req.block_roots.len() as u64,
             OutboundRequest::Ping(_) => 1,
             OutboundRequest::MetaData(_) => 1,
+            OutboundRequest::LightClientBootstrap(_) => 1,
         }
     }
 
@@ -126,6 +131,7 @@ impl<TSpec: EthSpec> OutboundRequest<TSpec> {
             OutboundRequest::BlobsByRoot(_) => Protocol::BlobsByRoot,
             OutboundRequest::Ping(_) => Protocol::Ping,
             OutboundRequest::MetaData(_) => Protocol::MetaData,
+            OutboundRequest::LightClientBootstrap(_) => Protocol::LightClientBootstrap,
         }
     }
 
@@ -139,6 +145,7 @@ impl<TSpec: EthSpec> OutboundRequest<TSpec> {
             OutboundRequest::BlocksByRoot(_) => ResponseTermination::BlocksByRoot,
             OutboundRequest::BlobsByRange(_) => ResponseTermination::BlobsByRange,
             OutboundRequest::BlobsByRoot(_) => ResponseTermination::BlobsByRoot,
+            OutboundRequest::LightClientBootstrap(_) => unreachable!(),
             OutboundRequest::Status(_) => unreachable!(),
             OutboundRequest::Goodbye(_) => unreachable!(),
             OutboundRequest::Ping(_) => unreachable!(),
@@ -198,6 +205,9 @@ impl<TSpec: EthSpec> std::fmt::Display for OutboundRequest<TSpec> {
             OutboundRequest::BlobsByRoot(req) => write!(f, "Blobs by root: {:?}", req),
             OutboundRequest::Ping(ping) => write!(f, "Ping: {}", ping.data),
             OutboundRequest::MetaData(_) => write!(f, "MetaData request"),
+            OutboundRequest::LightClientBootstrap(bootstrap) => {
+                write!(f, "Lightclient Bootstrap: {}", bootstrap.root)
+            }
         }
     }
 }
diff --git a/beacon_node/lighthouse_network/src/rpc/protocol.rs b/beacon_node/lighthouse_network/src/rpc/protocol.rs
index c95a6a0ca..549a0e720 100644
--- a/beacon_node/lighthouse_network/src/rpc/protocol.rs
+++ b/beacon_node/lighthouse_network/src/rpc/protocol.rs
@@ -181,6 +181,8 @@ pub enum Protocol {
     Ping,
     /// The `MetaData` protocol name.
     MetaData,
+    /// The `LightClientBootstrap` protocol name.
+    LightClientBootstrap,
 }
 
 /// RPC Versions
@@ -209,6 +211,7 @@ impl std::fmt::Display for Protocol {
             Protocol::BlobsByRoot => "beacon_block_and_blobs_sidecar_by_root",
             Protocol::Ping => "ping",
             Protocol::MetaData => "metadata",
+            Protocol::LightClientBootstrap => "light_client_bootstrap",
         };
         f.write_str(repr)
     }
@@ -237,6 +240,7 @@ impl std::fmt::Display for Version {
 pub struct RPCProtocol<TSpec: EthSpec> {
     pub fork_context: Arc<ForkContext>,
     pub max_rpc_size: usize,
+    pub enable_light_client_server: bool,
     pub phantom: PhantomData<TSpec>,
 }
 
@@ -246,7 +250,7 @@ impl<TSpec: EthSpec> UpgradeInfo for RPCProtocol<TSpec> {
 
     /// The list of supported RPC protocols for Lighthouse.
     fn protocol_info(&self) -> Self::InfoIter {
-        vec![
+        let mut supported_protocols = vec![
             ProtocolId::new(Protocol::Status, Version::V1, Encoding::SSZSnappy),
             ProtocolId::new(Protocol::Goodbye, Version::V1, Encoding::SSZSnappy),
             // V2 variants have higher preference then V1
@@ -257,7 +261,15 @@ impl<TSpec: EthSpec> UpgradeInfo for RPCProtocol<TSpec> {
             ProtocolId::new(Protocol::Ping, Version::V1, Encoding::SSZSnappy),
             ProtocolId::new(Protocol::MetaData, Version::V2, Encoding::SSZSnappy),
             ProtocolId::new(Protocol::MetaData, Version::V1, Encoding::SSZSnappy),
-        ]
+        ];
+        if self.enable_light_client_server {
+            supported_protocols.push(ProtocolId::new(
+                Protocol::LightClientBootstrap,
+                Version::V1,
+                Encoding::SSZSnappy,
+            ));
+        }
+        supported_protocols
     }
 }
 
@@ -326,6 +338,10 @@ impl ProtocolId {
                 <Ping as Encode>::ssz_fixed_len(),
                 <Ping as Encode>::ssz_fixed_len(),
             ),
+            Protocol::LightClientBootstrap => RpcLimits::new(
+                <LightClientBootstrapRequest as Encode>::ssz_fixed_len(),
+                <LightClientBootstrapRequest as Encode>::ssz_fixed_len(),
+            ),
             Protocol::MetaData => RpcLimits::new(0, 0), // Metadata requests are empty
         }
     }
@@ -353,6 +369,10 @@ impl ProtocolId {
                 <MetaDataV1<T> as Encode>::ssz_fixed_len(),
                 <MetaDataV2<T> as Encode>::ssz_fixed_len(),
             ),
+            Protocol::LightClientBootstrap => RpcLimits::new(
+                <LightClientBootstrapRequest as Encode>::ssz_fixed_len(),
+                <LightClientBootstrapRequest as Encode>::ssz_fixed_len(),
+            ),
         }
     }
 
@@ -460,67 +480,13 @@ pub enum InboundRequest<TSpec: EthSpec> {
     BlocksByRoot(BlocksByRootRequest),
     BlobsByRange(BlobsByRangeRequest),
     BlobsByRoot(BlobsByRootRequest),
+    LightClientBootstrap(LightClientBootstrapRequest),
     Ping(Ping),
     MetaData(PhantomData<TSpec>),
 }
 
-impl<TSpec: EthSpec> UpgradeInfo for InboundRequest<TSpec> {
-    type Info = ProtocolId;
-    type InfoIter = Vec<Self::Info>;
-
-    // add further protocols as we support more encodings/versions
-    fn protocol_info(&self) -> Self::InfoIter {
-        self.supported_protocols()
-    }
-}
-
 /// Implements the encoding per supported protocol for `RPCRequest`.
 impl<TSpec: EthSpec> InboundRequest<TSpec> {
-    pub fn supported_protocols(&self) -> Vec<ProtocolId> {
-        match self {
-            // add more protocols when versions/encodings are supported
-            InboundRequest::Status(_) => vec![ProtocolId::new(
-                Protocol::Status,
-                Version::V1,
-                Encoding::SSZSnappy,
-            )],
-            InboundRequest::Goodbye(_) => vec![ProtocolId::new(
-                Protocol::Goodbye,
-                Version::V1,
-                Encoding::SSZSnappy,
-            )],
-            InboundRequest::BlocksByRange(_) => vec![
-                // V2 has higher preference when negotiating a stream
-                ProtocolId::new(Protocol::BlocksByRange, Version::V2, Encoding::SSZSnappy),
-                ProtocolId::new(Protocol::BlocksByRange, Version::V1, Encoding::SSZSnappy),
-            ],
-            InboundRequest::BlocksByRoot(_) => vec![
-                // V2 has higher preference when negotiating a stream
-                ProtocolId::new(Protocol::BlocksByRoot, Version::V2, Encoding::SSZSnappy),
-                ProtocolId::new(Protocol::BlocksByRoot, Version::V1, Encoding::SSZSnappy),
-            ],
-            InboundRequest::BlobsByRange(_) => vec![ProtocolId::new(
-                Protocol::BlobsByRange,
-                Version::V1,
-                Encoding::SSZSnappy,
-            )],
-            InboundRequest::BlobsByRoot(_) => vec![ProtocolId::new(
-                Protocol::BlobsByRoot,
-                Version::V1,
-                Encoding::SSZSnappy,
-            )],
-            InboundRequest::Ping(_) => vec![ProtocolId::new(
-                Protocol::Ping,
-                Version::V1,
-                Encoding::SSZSnappy,
-            )],
-            InboundRequest::MetaData(_) => vec![
-                ProtocolId::new(Protocol::MetaData, Version::V2, Encoding::SSZSnappy),
-                ProtocolId::new(Protocol::MetaData, Version::V1, Encoding::SSZSnappy),
-            ],
-        }
-    }
-
     /* These functions are used in the handler for stream management */
 
     /// Number of responses expected for this request.
@@ -534,6 +500,7 @@ impl<TSpec: EthSpec> InboundRequest<TSpec> {
             InboundRequest::BlobsByRoot(req) => req.block_roots.len() as u64,
             InboundRequest::Ping(_) => 1,
             InboundRequest::MetaData(_) => 1,
+            InboundRequest::LightClientBootstrap(_) => 1,
         }
     }
 
@@ -548,6 +515,7 @@ impl<TSpec: EthSpec> InboundRequest<TSpec> {
             InboundRequest::BlobsByRoot(_) => Protocol::BlobsByRoot,
             InboundRequest::Ping(_) => Protocol::Ping,
             InboundRequest::MetaData(_) => Protocol::MetaData,
+            InboundRequest::LightClientBootstrap(_) => Protocol::LightClientBootstrap,
         }
     }
 
@@ -565,6 +533,7 @@ impl<TSpec: EthSpec> InboundRequest<TSpec> {
             InboundRequest::Goodbye(_) => unreachable!(),
             InboundRequest::Ping(_) => unreachable!(),
             InboundRequest::MetaData(_) => unreachable!(),
+            InboundRequest::LightClientBootstrap(_) => unreachable!(),
         }
     }
 }
@@ -670,6 +639,9 @@ impl<TSpec: EthSpec> std::fmt::Display for InboundRequest<TSpec> {
             InboundRequest::BlobsByRoot(req) => write!(f, "Blobs by root: {:?}", req),
             InboundRequest::Ping(ping) => write!(f, "Ping: {}", ping.data),
             InboundRequest::MetaData(_) => write!(f, "MetaData request"),
+            InboundRequest::LightClientBootstrap(bootstrap) => {
+                write!(f, "LightClientBootstrap: {}", bootstrap.root)
+            }
         }
     }
 }
diff --git a/beacon_node/lighthouse_network/src/rpc/rate_limiter.rs b/beacon_node/lighthouse_network/src/rpc/rate_limiter.rs
index 21f4dca7b..d021afcea 100644
--- a/beacon_node/lighthouse_network/src/rpc/rate_limiter.rs
+++ b/beacon_node/lighthouse_network/src/rpc/rate_limiter.rs
@@ -77,6 +77,8 @@ pub struct RPCRateLimiter {
     blbrange_rl: Limiter<PeerId>,
     /// BlobsByRoot rate limiter.
     blbroot_rl: Limiter<PeerId>,
+    /// LightClientBootstrap rate limiter.
+    lcbootstrap_rl: Limiter<PeerId>,
 }
 
 /// Error type for non conformant requests
@@ -106,6 +108,8 @@ pub struct RPCRateLimiterBuilder {
     blbrange_quota: Option<Quota>,
     /// Quota for the BlobsByRoot protocol.
     blbroot_quota: Option<Quota>,
+    /// Quota for the LightClientBootstrap protocol.
+    lcbootstrap_quota: Option<Quota>,
 }
 
 impl RPCRateLimiterBuilder {
@@ -126,6 +130,7 @@ impl RPCRateLimiterBuilder {
             Protocol::BlocksByRoot => self.bbroots_quota = q,
             Protocol::BlobsByRange => self.blbrange_quota = q,
             Protocol::BlobsByRoot => self.blbroot_quota = q,
+            Protocol::LightClientBootstrap => self.lcbootstrap_quota = q,
         }
         self
     }
@@ -165,6 +170,9 @@ impl RPCRateLimiterBuilder {
         let bbrange_quota = self
             .bbrange_quota
             .ok_or("BlocksByRange quota not specified")?;
+        let lcbootstrap_quote = self
+            .lcbootstrap_quota
+            .ok_or("LightClientBootstrap quota not specified")?;
 
         let blbrange_quota = self
             .blbrange_quota
@@ -183,6 +191,7 @@ impl RPCRateLimiterBuilder {
         let bbrange_rl = Limiter::from_quota(bbrange_quota)?;
         let blbrange_rl = Limiter::from_quota(blbrange_quota)?;
         let blbroot_rl = Limiter::from_quota(blbroots_quota)?;
+        let lcbootstrap_rl = Limiter::from_quota(lcbootstrap_quote)?;
 
         // check for peers to prune every 30 seconds, starting in 30 seconds
         let prune_every = tokio::time::Duration::from_secs(30);
@@ -198,6 +207,7 @@ impl RPCRateLimiterBuilder {
             bbrange_rl,
             blbrange_rl,
             blbroot_rl,
+            lcbootstrap_rl,
             init_time: Instant::now(),
         })
     }
@@ -223,6 +233,7 @@ impl RPCRateLimiter {
             Protocol::BlocksByRoot => &mut self.bbroots_rl,
             Protocol::BlobsByRange => &mut self.blbrange_rl,
             Protocol::BlobsByRoot => &mut self.blbroot_rl,
+            Protocol::LightClientBootstrap => &mut self.lcbootstrap_rl,
         };
         check(limiter)
     }
diff --git a/beacon_node/lighthouse_network/src/service/api_types.rs b/beacon_node/lighthouse_network/src/service/api_types.rs
index b9360aeac..b6a033020 100644
--- a/beacon_node/lighthouse_network/src/service/api_types.rs
+++ b/beacon_node/lighthouse_network/src/service/api_types.rs
@@ -1,13 +1,14 @@
 use std::sync::Arc;
 
 use libp2p::core::connection::ConnectionId;
+use types::light_client_bootstrap::LightClientBootstrap;
 use types::{BlobsSidecar, EthSpec, SignedBeaconBlock};
 
 use crate::rpc::methods::{BlobsByRangeRequest, BlobsByRootRequest};
 use crate::rpc::{
     methods::{
-        BlocksByRangeRequest, BlocksByRootRequest, OldBlocksByRangeRequest, RPCCodedResponse,
-        RPCResponse, ResponseTermination, StatusMessage,
+        BlocksByRangeRequest, BlocksByRootRequest, LightClientBootstrapRequest,
+        OldBlocksByRangeRequest, RPCCodedResponse, RPCResponse, ResponseTermination, StatusMessage,
     },
     OutboundRequest, SubstreamId,
 };
@@ -38,6 +39,8 @@ pub enum Request {
     BlobsByRange(BlobsByRangeRequest),
     /// A request blocks root request.
     BlocksByRoot(BlocksByRootRequest),
+    // light client bootstrap request
+    LightClientBootstrap(LightClientBootstrapRequest),
     /// A request blobs root request.
     BlobsByRoot(BlobsByRootRequest),
 }
@@ -54,6 +57,7 @@ impl<TSpec: EthSpec> std::convert::From<Request> for OutboundRequest<TSpec> {
                 })
             }
             Request::BlobsByRange(r) => OutboundRequest::BlobsByRange(r),
+            Request::LightClientBootstrap(b) => OutboundRequest::LightClientBootstrap(b),
             Request::BlobsByRoot(r) => OutboundRequest::BlobsByRoot(r),
             Request::Status(s) => OutboundRequest::Status(s),
         }
@@ -76,6 +80,8 @@ pub enum Response<TSpec: EthSpec> {
     BlobsByRange(Option<Arc<BlobsSidecar<TSpec>>>),
     /// A response to a get BLOCKS_BY_ROOT request.
     BlocksByRoot(Option<Arc<SignedBeaconBlock<TSpec>>>),
+    /// A response to a LightClientUpdate request.
+    LightClientBootstrap(LightClientBootstrap<TSpec>),
     /// A response to a get BLOBS_BY_ROOT request.
     BlobsByRoot(Option<Arc<SignedBeaconBlockAndBlobsSidecar<TSpec>>>),
 }
@@ -100,6 +106,9 @@ impl<TSpec: EthSpec> std::convert::From<Response<TSpec>> for RPCCodedResponse<TS
                 None => RPCCodedResponse::StreamTermination(ResponseTermination::BlobsByRange),
             },
             Response::Status(s) => RPCCodedResponse::Success(RPCResponse::Status(s)),
+            Response::LightClientBootstrap(b) => {
+                RPCCodedResponse::Success(RPCResponse::LightClientBootstrap(b))
+            }
         }
     }
 }
diff --git a/beacon_node/lighthouse_network/src/service/behaviour.rs b/beacon_node/lighthouse_network/src/service/behaviour.rs
index 8327293a7..3adc940a6 100644
--- a/beacon_node/lighthouse_network/src/service/behaviour.rs
+++ b/beacon_node/lighthouse_network/src/service/behaviour.rs
@@ -8,7 +8,6 @@ use libp2p::gossipsub::subscription_filter::{
 };
 use libp2p::gossipsub::Gossipsub as BaseGossipsub;
 use libp2p::identify::Identify;
-use libp2p::swarm::NetworkBehaviour;
 use libp2p::NetworkBehaviour;
 use types::EthSpec;
 
diff --git a/beacon_node/lighthouse_network/src/service/mod.rs b/beacon_node/lighthouse_network/src/service/mod.rs
index 2c6eb56b2..aaa7036fa 100644
--- a/beacon_node/lighthouse_network/src/service/mod.rs
+++ b/beacon_node/lighthouse_network/src/service/mod.rs
@@ -262,7 +262,11 @@ impl<AppReqId: ReqId, TSpec: EthSpec> Network<AppReqId, TSpec> {
             (gossipsub, update_gossipsub_scores)
         };
 
-        let eth2_rpc = RPC::new(ctx.fork_context.clone(), log.clone());
+        let eth2_rpc = RPC::new(
+            ctx.fork_context.clone(),
+            config.enable_light_client_server,
+            log.clone(),
+        );
 
         let discovery = {
             // Build and start the discovery sub-behaviour
@@ -981,6 +985,9 @@ impl<AppReqId: ReqId, TSpec: EthSpec> Network<AppReqId, TSpec> {
             Request::Status(_) => {
                 metrics::inc_counter_vec(&metrics::TOTAL_RPC_REQUESTS, &["status"])
             }
+            Request::LightClientBootstrap(_) => {
+                metrics::inc_counter_vec(&metrics::TOTAL_RPC_REQUESTS, &["light_client_bootstrap"])
+            }
             Request::BlocksByRange { .. } => {
                 metrics::inc_counter_vec(&metrics::TOTAL_RPC_REQUESTS, &["blocks_by_range"])
             }
@@ -1269,6 +1276,14 @@ impl<AppReqId: ReqId, TSpec: EthSpec> Network<AppReqId, TSpec> {
                             self.build_request(peer_request_id, peer_id, Request::BlobsByRoot(req));
                         Some(event)
                     }
+                    InboundRequest::LightClientBootstrap(req) => {
+                        let event = self.build_request(
+                            peer_request_id,
+                            peer_id,
+                            Request::LightClientBootstrap(req),
+                        );
+                        Some(event)
+                    }
                 }
             }
             Ok(RPCReceived::Response(id, resp)) => {
@@ -1302,6 +1317,10 @@ impl<AppReqId: ReqId, TSpec: EthSpec> Network<AppReqId, TSpec> {
                     RPCResponse::BlobsByRoot(resp) => {
                         self.build_response(id, peer_id, Response::BlobsByRoot(Some(resp)))
                     }
+                    // Should never be reached
+                    RPCResponse::LightClientBootstrap(bootstrap) => {
+                        self.build_response(id, peer_id, Response::LightClientBootstrap(bootstrap))
+                    }
                 }
             }
             Ok(RPCReceived::EndOfStream(id, termination)) => {
diff --git a/beacon_node/lighthouse_network/src/types/sync_state.rs b/beacon_node/lighthouse_network/src/types/sync_state.rs
index ce03f61ff..5f09aec27 100644
--- a/beacon_node/lighthouse_network/src/types/sync_state.rs
+++ b/beacon_node/lighthouse_network/src/types/sync_state.rs
@@ -74,6 +74,17 @@ impl SyncState {
         }
     }
 
+    pub fn is_syncing_finalized(&self) -> bool {
+        match self {
+            SyncState::SyncingFinalized { .. } => true,
+            SyncState::SyncingHead { .. } => false,
+            SyncState::SyncTransition => false,
+            SyncState::BackFillSyncing { .. } => false,
+            SyncState::Synced => false,
+            SyncState::Stalled => false,
+        }
+    }
+
     /// Returns true if the node is synced.
     ///
     /// NOTE: We consider the node synced if it is fetching old historical blocks.
diff --git a/beacon_node/network/src/beacon_processor/mod.rs b/beacon_node/network/src/beacon_processor/mod.rs
index e018fdf76..b002e6469 100644
--- a/beacon_node/network/src/beacon_processor/mod.rs
+++ b/beacon_node/network/src/beacon_processor/mod.rs
@@ -41,11 +41,12 @@
 use crate::sync::manager::BlockProcessType;
 use crate::{metrics, service::NetworkMessage, sync::SyncMessage};
 use beacon_chain::parking_lot::Mutex;
-use beacon_chain::{BeaconChain, BeaconChainTypes, GossipVerifiedBlock};
+use beacon_chain::{BeaconChain, BeaconChainTypes, GossipVerifiedBlock, NotifyExecutionLayer};
 use derivative::Derivative;
 use futures::stream::{Stream, StreamExt};
 use futures::task::Poll;
 use lighthouse_network::rpc::methods::{BlobsByRangeRequest, BlobsByRootRequest};
+use lighthouse_network::rpc::LightClientBootstrapRequest;
 use lighthouse_network::{
     rpc::{BlocksByRangeRequest, BlocksByRootRequest, StatusMessage},
     Client, MessageId, NetworkGlobals, PeerId, PeerRequestId,
@@ -171,6 +172,10 @@ const MAX_BLOCK_AND_BLOBS_BY_ROOTS_QUEUE_LEN: usize = 1_024;
 /// is activated.
 const MAX_BLS_TO_EXECUTION_CHANGE_QUEUE_LEN: usize = 16_384;
 
+/// The maximum number of queued `LightClientBootstrapRequest` objects received from the network RPC that
+/// will be stored before we start dropping them.
+const MAX_LIGHT_CLIENT_BOOTSTRAP_QUEUE_LEN: usize = 1_024;
+
 /// The name of the manager tokio task.
 const MANAGER_TASK_NAME: &str = "beacon_processor_manager";
 
@@ -213,6 +218,7 @@ pub const BLOCKS_BY_RANGE_REQUEST: &str = "blocks_by_range_request";
 pub const BLOCKS_BY_ROOTS_REQUEST: &str = "blocks_by_roots_request";
 pub const BLOBS_BY_RANGE_REQUEST: &str = "blobs_by_range_request";
 pub const BLOBS_BY_ROOTS_REQUEST: &str = "blobs_by_roots_request";
+pub const LIGHT_CLIENT_BOOTSTRAP_REQUEST: &str = "light_client_bootstrap";
 pub const UNKNOWN_BLOCK_ATTESTATION: &str = "unknown_block_attestation";
 pub const UNKNOWN_BLOCK_AGGREGATE: &str = "unknown_block_aggregate";
 pub const GOSSIP_BLS_TO_EXECUTION_CHANGE: &str = "gossip_bls_to_execution_change";
@@ -627,6 +633,22 @@ impl<T: BeaconChainTypes> WorkEvent<T> {
         }
     }
 
+    /// Create a new work event to process `LightClientBootstrap`s from the RPC network.
+    pub fn lightclient_bootstrap_request(
+        peer_id: PeerId,
+        request_id: PeerRequestId,
+        request: LightClientBootstrapRequest,
+    ) -> Self {
+        Self {
+            drop_during_sync: true,
+            work: Work::LightClientBootstrapRequest {
+                peer_id,
+                request_id,
+                request,
+            },
+        }
+    }
+
     pub fn blobs_by_root_request(
         peer_id: PeerId,
         request_id: PeerRequestId,
@@ -835,6 +857,11 @@ pub enum Work<T: BeaconChainTypes> {
         peer_id: PeerId,
         bls_to_execution_change: Box<SignedBlsToExecutionChange>,
     },
+    LightClientBootstrapRequest {
+        peer_id: PeerId,
+        request_id: PeerRequestId,
+        request: LightClientBootstrapRequest,
+    },
     BlobsByRootsRequest {
         peer_id: PeerId,
         request_id: PeerRequestId,
@@ -865,6 +892,7 @@ impl<T: BeaconChainTypes> Work<T> {
             Work::BlocksByRootsRequest { .. } => BLOCKS_BY_ROOTS_REQUEST,
             Work::BlobsByRangeRequest { .. } => BLOBS_BY_RANGE_REQUEST,
             Work::BlobsByRootsRequest { .. } => BLOBS_BY_ROOTS_REQUEST,
+            Work::LightClientBootstrapRequest { .. } => LIGHT_CLIENT_BOOTSTRAP_REQUEST,
             Work::UnknownBlockAttestation { .. } => UNKNOWN_BLOCK_ATTESTATION,
             Work::UnknownBlockAggregate { .. } => UNKNOWN_BLOCK_AGGREGATE,
             Work::GossipBlsToExecutionChange { .. } => GOSSIP_BLS_TO_EXECUTION_CHANGE,
@@ -1017,6 +1045,7 @@ impl<T: BeaconChainTypes> BeaconProcessor<T> {
         let mut gossip_bls_to_execution_change_queue =
             FifoQueue::new(MAX_BLS_TO_EXECUTION_CHANGE_QUEUE_LEN);
 
+        let mut lcbootstrap_queue = FifoQueue::new(MAX_LIGHT_CLIENT_BOOTSTRAP_QUEUE_LEN);
         // Channels for sending work to the re-process scheduler (`work_reprocessing_tx`) and to
         // receive them back once they are ready (`ready_work_rx`).
         let (ready_work_tx, ready_work_rx) = mpsc::channel(MAX_SCHEDULED_WORK_QUEUE_LEN);
@@ -1266,6 +1295,8 @@ impl<T: BeaconChainTypes> BeaconProcessor<T> {
                         } else if let Some(item) = backfill_chain_segment.pop() {
                             self.spawn_worker(item, toolbox);
                         // This statement should always be the final else statement.
+                        } else if let Some(item) = lcbootstrap_queue.pop() {
+                            self.spawn_worker(item, toolbox);
                         } else {
                             // Let the journal know that a worker is freed and there's nothing else
                             // for it to do.
@@ -1372,6 +1403,9 @@ impl<T: BeaconChainTypes> BeaconProcessor<T> {
                             Work::BlobsByRangeRequest { .. } => {
                                 blbrange_queue.push(work, work_id, &self.log)
                             }
+                            Work::LightClientBootstrapRequest { .. } => {
+                                lcbootstrap_queue.push(work, work_id, &self.log)
+                            }
                             Work::UnknownBlockAttestation { .. } => {
                                 unknown_block_attestation_queue.push(work)
                             }
@@ -1735,8 +1769,24 @@ impl<T: BeaconChainTypes> BeaconProcessor<T> {
             /*
              * Verification for a chain segment (multiple blocks).
              */
-            Work::ChainSegment { process_id, blocks } => task_spawner
-                .spawn_async(async move { worker.process_chain_segment(process_id, blocks).await }),
+            Work::ChainSegment { process_id, blocks } => {
+                let notify_execution_layer = if self
+                    .network_globals
+                    .sync_state
+                    .read()
+                    .is_syncing_finalized()
+                {
+                    NotifyExecutionLayer::No
+                } else {
+                    NotifyExecutionLayer::Yes
+                };
+
+                task_spawner.spawn_async(async move {
+                    worker
+                        .process_chain_segment(process_id, blocks, notify_execution_layer)
+                        .await
+                })
+            }
             /*
              * Processing of Status Messages.
              */
@@ -1775,7 +1825,6 @@ impl<T: BeaconChainTypes> BeaconProcessor<T> {
                     request,
                 )
             }),
-
             Work::BlobsByRangeRequest {
                 peer_id,
                 request_id,
@@ -1804,6 +1853,16 @@ impl<T: BeaconChainTypes> BeaconProcessor<T> {
                 )
             }),
 
+            /*
+             * Processing of lightclient bootstrap requests from other peers.
+             */
+            Work::LightClientBootstrapRequest {
+                peer_id,
+                request_id,
+                request,
+            } => task_spawner.spawn_blocking(move || {
+                worker.handle_light_client_bootstrap(peer_id, request_id, request)
+            }),
             Work::UnknownBlockAttestation {
                 message_id,
                 peer_id,
diff --git a/beacon_node/network/src/beacon_processor/worker/gossip_methods.rs b/beacon_node/network/src/beacon_processor/worker/gossip_methods.rs
index d175b4924..80a8e1179 100644
--- a/beacon_node/network/src/beacon_processor/worker/gossip_methods.rs
+++ b/beacon_node/network/src/beacon_processor/worker/gossip_methods.rs
@@ -8,7 +8,7 @@ use beacon_chain::{
     sync_committee_verification::{self, Error as SyncCommitteeError},
     validator_monitor::get_block_delay_ms,
     BeaconChainError, BeaconChainTypes, BlockError, CountUnrealized, ForkChoiceError,
-    GossipVerifiedBlock,
+    GossipVerifiedBlock, NotifyExecutionLayer,
 };
 use lighthouse_network::{Client, MessageAcceptance, MessageId, PeerAction, PeerId, ReportSource};
 use slog::{crit, debug, error, info, trace, warn};
@@ -797,7 +797,7 @@ impl<T: BeaconChainTypes> Worker<T> {
             | Err(e @ BlockError::BlockIsAlreadyKnown)
             | Err(e @ BlockError::RepeatProposal { .. })
             | Err(e @ BlockError::NotFinalizedDescendant { .. }) => {
-                debug!(self.log, "Could not verify block for gossip, ignoring the block";
+                debug!(self.log, "Could not verify block for gossip. Ignoring the block";
                             "error" => %e);
                 // Prevent recurring behaviour by penalizing the peer slightly.
                 self.gossip_penalize_peer(
@@ -809,7 +809,7 @@ impl<T: BeaconChainTypes> Worker<T> {
                 return None;
             }
             Err(ref e @ BlockError::ExecutionPayloadError(ref epe)) if !epe.penalize_peer() => {
-                debug!(self.log, "Could not verify block for gossip, ignoring the block";
+                debug!(self.log, "Could not verify block for gossip. Ignoring the block";
                             "error" => %e);
                 self.propagate_validation_result(message_id, peer_id, MessageAcceptance::Ignore);
                 return None;
@@ -831,7 +831,7 @@ impl<T: BeaconChainTypes> Worker<T> {
             // TODO(merge): reconsider peer scoring for this event.
             | Err(e @ BlockError::ParentExecutionPayloadInvalid { .. })
             | Err(e @ BlockError::GenesisBlock) => {
-                warn!(self.log, "Could not verify block for gossip, rejecting the block";
+                warn!(self.log, "Could not verify block for gossip. Rejecting the block";
                             "error" => %e);
                 self.propagate_validation_result(message_id, peer_id, MessageAcceptance::Reject);
                 self.gossip_penalize_peer(
@@ -939,7 +939,12 @@ impl<T: BeaconChainTypes> Worker<T> {
 
         match self
             .chain
-            .process_block(block_root, verified_block, CountUnrealized::True)
+            .process_block(
+                block_root,
+                verified_block,
+                CountUnrealized::True,
+                NotifyExecutionLayer::Yes,
+            )
             .await
         {
             Ok(block_root) => {
diff --git a/beacon_node/network/src/beacon_processor/worker/mod.rs b/beacon_node/network/src/beacon_processor/worker/mod.rs
index f907c49b7..1cbc64b63 100644
--- a/beacon_node/network/src/beacon_processor/worker/mod.rs
+++ b/beacon_node/network/src/beacon_processor/worker/mod.rs
@@ -38,7 +38,7 @@ impl<T: BeaconChainTypes> Worker<T> {
     /// Creates a log if there is an internal error.
     fn send_network_message(&self, message: NetworkMessage<T::EthSpec>) {
         self.network_tx.send(message).unwrap_or_else(|e| {
-            debug!(self.log, "Could not send message to the network service, likely shutdown";
+            debug!(self.log, "Could not send message to the network service. Likely shutdown";
                 "error" => %e)
         });
     }
diff --git a/beacon_node/network/src/beacon_processor/worker/rpc_methods.rs b/beacon_node/network/src/beacon_processor/worker/rpc_methods.rs
index e95bd4e85..87e8a3fc4 100644
--- a/beacon_node/network/src/beacon_processor/worker/rpc_methods.rs
+++ b/beacon_node/network/src/beacon_processor/worker/rpc_methods.rs
@@ -15,6 +15,7 @@ use slot_clock::SlotClock;
 use ssz_types::VariableList;
 use std::sync::Arc;
 use task_executor::TaskExecutor;
+use types::light_client_bootstrap::LightClientBootstrap;
 use types::{Epoch, EthSpec, Hash256, SignedBeaconBlockAndBlobsSidecar, Slot};
 
 use super::Worker;
@@ -308,6 +309,79 @@ impl<T: BeaconChainTypes> Worker<T> {
         )
     }
 
+    /// Handle a `BlocksByRoot` request from the peer.
+    pub fn handle_light_client_bootstrap(
+        self,
+        peer_id: PeerId,
+        request_id: PeerRequestId,
+        request: LightClientBootstrapRequest,
+    ) {
+        let block_root = request.root;
+        let state_root = match self.chain.get_blinded_block(&block_root) {
+            Ok(signed_block) => match signed_block {
+                Some(signed_block) => signed_block.state_root(),
+                None => {
+                    self.send_error_response(
+                        peer_id,
+                        RPCResponseErrorCode::ResourceUnavailable,
+                        "Bootstrap not avaiable".into(),
+                        request_id,
+                    );
+                    return;
+                }
+            },
+            Err(_) => {
+                self.send_error_response(
+                    peer_id,
+                    RPCResponseErrorCode::ResourceUnavailable,
+                    "Bootstrap not avaiable".into(),
+                    request_id,
+                );
+                return;
+            }
+        };
+        let mut beacon_state = match self.chain.get_state(&state_root, None) {
+            Ok(beacon_state) => match beacon_state {
+                Some(state) => state,
+                None => {
+                    self.send_error_response(
+                        peer_id,
+                        RPCResponseErrorCode::ResourceUnavailable,
+                        "Bootstrap not avaiable".into(),
+                        request_id,
+                    );
+                    return;
+                }
+            },
+            Err(_) => {
+                self.send_error_response(
+                    peer_id,
+                    RPCResponseErrorCode::ResourceUnavailable,
+                    "Bootstrap not avaiable".into(),
+                    request_id,
+                );
+                return;
+            }
+        };
+        let bootstrap = match LightClientBootstrap::from_beacon_state(&mut beacon_state) {
+            Ok(bootstrap) => bootstrap,
+            Err(_) => {
+                self.send_error_response(
+                    peer_id,
+                    RPCResponseErrorCode::ResourceUnavailable,
+                    "Bootstrap not avaiable".into(),
+                    request_id,
+                );
+                return;
+            }
+        };
+        self.send_response(
+            peer_id,
+            Response::LightClientBootstrap(bootstrap),
+            request_id,
+        )
+    }
+
     /// Handle a `BlocksByRange` request from the peer.
     pub fn handle_blocks_by_range_request(
         self,
diff --git a/beacon_node/network/src/beacon_processor/worker/sync_methods.rs b/beacon_node/network/src/beacon_processor/worker/sync_methods.rs
index 05a4fb75a..dafc00bdd 100644
--- a/beacon_node/network/src/beacon_processor/worker/sync_methods.rs
+++ b/beacon_node/network/src/beacon_processor/worker/sync_methods.rs
@@ -10,6 +10,7 @@ use crate::sync::{BatchProcessResult, ChainId};
 use beacon_chain::CountUnrealized;
 use beacon_chain::{
     BeaconChainError, BeaconChainTypes, BlockError, ChainSegmentResult, HistoricalBlockError,
+    NotifyExecutionLayer,
 };
 use lighthouse_network::PeerAction;
 use slog::{debug, error, info, warn};
@@ -89,7 +90,12 @@ impl<T: BeaconChainTypes> Worker<T> {
         let slot = block.slot();
         let result = self
             .chain
-            .process_block(block_root, block, CountUnrealized::True)
+            .process_block(
+                block_root,
+                block,
+                CountUnrealized::True,
+                NotifyExecutionLayer::Yes,
+            )
             .await;
 
         metrics::inc_counter(&metrics::BEACON_PROCESSOR_RPC_BLOCK_IMPORTED_TOTAL);
@@ -131,6 +137,7 @@ impl<T: BeaconChainTypes> Worker<T> {
         &self,
         sync_type: ChainSegmentProcessId,
         downloaded_blocks: Vec<BlockWrapper<T::EthSpec>>,
+        notify_execution_layer: NotifyExecutionLayer,
     ) {
         let result = match sync_type {
             // this a request from the range sync
@@ -140,7 +147,11 @@ impl<T: BeaconChainTypes> Worker<T> {
                 let sent_blocks = downloaded_blocks.len();
 
                 match self
-                    .process_blocks(downloaded_blocks.iter(), count_unrealized)
+                    .process_blocks(
+                        downloaded_blocks.iter(),
+                        count_unrealized,
+                        notify_execution_layer,
+                    )
                     .await
                 {
                     (_, Ok(_)) => {
@@ -230,7 +241,11 @@ impl<T: BeaconChainTypes> Worker<T> {
                 // parent blocks are ordered from highest slot to lowest, so we need to process in
                 // reverse
                 match self
-                    .process_blocks(downloaded_blocks.iter().rev(), CountUnrealized::True)
+                    .process_blocks(
+                        downloaded_blocks.iter().rev(),
+                        CountUnrealized::True,
+                        notify_execution_layer,
+                    )
                     .await
                 {
                     (imported_blocks, Err(e)) => {
@@ -261,11 +276,12 @@ impl<T: BeaconChainTypes> Worker<T> {
         &self,
         downloaded_blocks: impl Iterator<Item = &'a BlockWrapper<T::EthSpec>>,
         count_unrealized: CountUnrealized,
+        notify_execution_layer: NotifyExecutionLayer,
     ) -> (usize, Result<(), ChainSegmentFailed>) {
         let blocks: Vec<_> = downloaded_blocks.cloned().collect();
         match self
             .chain
-            .process_chain_segment(blocks, count_unrealized)
+            .process_chain_segment(blocks, count_unrealized, notify_execution_layer)
             .await
         {
             ChainSegmentResult::Successful { imported_blocks } => {
@@ -443,7 +459,7 @@ impl<T: BeaconChainTypes> Worker<T> {
                 } else {
                     // The block is in the future, but not too far.
                     debug!(
-                        self.log, "Block is slightly ahead of our slot clock, ignoring.";
+                        self.log, "Block is slightly ahead of our slot clock. Ignoring.";
                         "present_slot" => present_slot,
                         "block_slot" => block_slot,
                         "FUTURE_SLOT_TOLERANCE" => FUTURE_SLOT_TOLERANCE,
diff --git a/beacon_node/network/src/router/mod.rs b/beacon_node/network/src/router/mod.rs
index 428dc00b2..95c9a10ba 100644
--- a/beacon_node/network/src/router/mod.rs
+++ b/beacon_node/network/src/router/mod.rs
@@ -174,6 +174,9 @@ impl<T: BeaconChainTypes> Router<T> {
             Request::BlobsByRoot(request) => self
                 .processor
                 .on_blobs_by_root_request(peer_id, id, request),
+            Request::LightClientBootstrap(request) => self
+                .processor
+                .on_lightclient_bootstrap(peer_id, id, request),
         }
     }
 
@@ -206,6 +209,7 @@ impl<T: BeaconChainTypes> Router<T> {
                 self.processor
                     .on_blobs_by_root_response(peer_id, request_id, beacon_blob);
             }
+            Response::LightClientBootstrap(_) => unreachable!(),
         }
     }
 
diff --git a/beacon_node/network/src/router/processor.rs b/beacon_node/network/src/router/processor.rs
index e4e2f26c4..f4d371783 100644
--- a/beacon_node/network/src/router/processor.rs
+++ b/beacon_node/network/src/router/processor.rs
@@ -185,6 +185,18 @@ impl<T: BeaconChainTypes> Processor<T> {
         ))
     }
 
+    /// Handle a `LightClientBootstrap` request from the peer.
+    pub fn on_lightclient_bootstrap(
+        &mut self,
+        peer_id: PeerId,
+        request_id: PeerRequestId,
+        request: LightClientBootstrapRequest,
+    ) {
+        self.send_beacon_processor_work(BeaconWorkEvent::lightclient_bootstrap_request(
+            peer_id, request_id, request,
+        ))
+    }
+
     /// Handle a `BlocksByRange` request from the peer.
     pub fn on_blocks_by_range_request(
         &mut self,
diff --git a/beacon_node/network/src/sync/block_lookups/mod.rs b/beacon_node/network/src/sync/block_lookups/mod.rs
index abd332f3d..3b0600775 100644
--- a/beacon_node/network/src/sync/block_lookups/mod.rs
+++ b/beacon_node/network/src/sync/block_lookups/mod.rs
@@ -1,4 +1,5 @@
 use std::collections::hash_map::Entry;
+use std::collections::HashMap;
 use std::time::Duration;
 
 use beacon_chain::{BeaconChainTypes, BlockError};
@@ -16,6 +17,7 @@ use types::signed_block_and_blobs::BlockWrapper;
 use crate::beacon_processor::{ChainSegmentProcessId, WorkEvent};
 use crate::metrics;
 
+use self::parent_lookup::PARENT_FAIL_TOLERANCE;
 use self::{
     parent_lookup::{ParentLookup, VerifyError},
     single_block_lookup::SingleBlockRequest,
@@ -39,8 +41,11 @@ const FAILED_CHAINS_CACHE_EXPIRY_SECONDS: u64 = 60;
 const SINGLE_BLOCK_LOOKUP_MAX_ATTEMPTS: u8 = 3;
 
 pub(crate) struct BlockLookups<T: BeaconChainTypes> {
-    /// A collection of parent block lookups.
-    parent_queue: SmallVec<[ParentLookup<T>; 3]>,
+    /// Parent chain lookups being downloaded.
+    parent_lookups: SmallVec<[ParentLookup<T>; 3]>,
+
+    processing_parent_lookups:
+        HashMap<Hash256, (Vec<Hash256>, SingleBlockRequest<PARENT_FAIL_TOLERANCE>)>,
 
     /// A cache of failed chain lookups to prevent duplicate searches.
     failed_chains: LRUTimeCache<Hash256>,
@@ -58,7 +63,8 @@ pub(crate) struct BlockLookups<T: BeaconChainTypes> {
 impl<T: BeaconChainTypes> BlockLookups<T> {
     pub fn new(log: Logger) -> Self {
         Self {
-            parent_queue: Default::default(),
+            parent_lookups: Default::default(),
+            processing_parent_lookups: Default::default(),
             failed_chains: LRUTimeCache::new(Duration::from_secs(
                 FAILED_CHAINS_CACHE_EXPIRY_SECONDS,
             )),
@@ -81,6 +87,23 @@ impl<T: BeaconChainTypes> BlockLookups<T> {
             return;
         }
 
+        if self.parent_lookups.iter_mut().any(|parent_req| {
+            parent_req.add_peer(&hash, &peer_id) || parent_req.contains_block(&hash)
+        }) {
+            // If the block was already downloaded, or is being downloaded in this moment, do not
+            // request it.
+            return;
+        }
+
+        if self
+            .processing_parent_lookups
+            .values()
+            .any(|(hashes, _last_parent_request)| hashes.contains(&hash))
+        {
+            // we are already processing this block, ignore it.
+            return;
+        }
+
         debug!(
             self.log,
             "Searching for block";
@@ -123,8 +146,8 @@ impl<T: BeaconChainTypes> BlockLookups<T> {
 
         // Make sure this block is not already downloaded, and that neither it or its parent is
         // being searched for.
-        if self.parent_queue.iter_mut().any(|parent_req| {
-            parent_req.contains_block(block.block())
+        if self.parent_lookups.iter_mut().any(|parent_req| {
+            parent_req.contains_block(&block_root)
                 || parent_req.add_peer(&block_root, &peer_id)
                 || parent_req.add_peer(&parent_root, &peer_id)
         }) {
@@ -132,6 +155,15 @@ impl<T: BeaconChainTypes> BlockLookups<T> {
             return;
         }
 
+        if self
+            .processing_parent_lookups
+            .values()
+            .any(|(hashes, _peers)| hashes.contains(&block_root) || hashes.contains(&parent_root))
+        {
+            // we are already processing this block, ignore it.
+            return;
+        }
+
         let parent_lookup = ParentLookup::new(block_root, block, peer_id);
         self.request_parent(parent_lookup, cx);
     }
@@ -212,11 +244,11 @@ impl<T: BeaconChainTypes> BlockLookups<T> {
         cx: &mut SyncNetworkContext<T>,
     ) {
         let mut parent_lookup = if let Some(pos) = self
-            .parent_queue
+            .parent_lookups
             .iter()
             .position(|request| request.pending_response(id))
         {
-            self.parent_queue.remove(pos)
+            self.parent_lookups.remove(pos)
         } else {
             if block.is_some() {
                 debug!(self.log, "Response for a parent lookup request that was not found"; "peer_id" => %peer_id);
@@ -238,13 +270,13 @@ impl<T: BeaconChainTypes> BlockLookups<T> {
                     )
                     .is_ok()
                 {
-                    self.parent_queue.push(parent_lookup)
+                    self.parent_lookups.push(parent_lookup)
                 }
             }
             Ok(None) => {
                 // Request finished successfully, nothing else to do. It will be removed after the
                 // processing result arrives.
-                self.parent_queue.push(parent_lookup);
+                self.parent_lookups.push(parent_lookup);
             }
             Err(e) => match e {
                 VerifyError::RootMismatch
@@ -281,7 +313,7 @@ impl<T: BeaconChainTypes> BlockLookups<T> {
 
         metrics::set_gauge(
             &metrics::SYNC_PARENT_BLOCK_LOOKUPS,
-            self.parent_queue.len() as i64,
+            self.parent_lookups.len() as i64,
         );
     }
 
@@ -329,11 +361,11 @@ impl<T: BeaconChainTypes> BlockLookups<T> {
 
         /* Check disconnection for parent lookups */
         while let Some(pos) = self
-            .parent_queue
+            .parent_lookups
             .iter_mut()
             .position(|req| req.check_peer_disconnected(peer_id).is_err())
         {
-            let parent_lookup = self.parent_queue.remove(pos);
+            let parent_lookup = self.parent_lookups.remove(pos);
             trace!(self.log, "Parent lookup's peer disconnected"; &parent_lookup);
             self.request_parent(parent_lookup, cx);
         }
@@ -347,11 +379,11 @@ impl<T: BeaconChainTypes> BlockLookups<T> {
         cx: &mut SyncNetworkContext<T>,
     ) {
         if let Some(pos) = self
-            .parent_queue
+            .parent_lookups
             .iter()
             .position(|request| request.pending_response(id))
         {
-            let mut parent_lookup = self.parent_queue.remove(pos);
+            let mut parent_lookup = self.parent_lookups.remove(pos);
             parent_lookup.download_failed();
             trace!(self.log, "Parent lookup request failed"; &parent_lookup);
             self.request_parent(parent_lookup, cx);
@@ -360,7 +392,7 @@ impl<T: BeaconChainTypes> BlockLookups<T> {
         };
         metrics::set_gauge(
             &metrics::SYNC_PARENT_BLOCK_LOOKUPS,
-            self.parent_queue.len() as i64,
+            self.parent_lookups.len() as i64,
         );
     }
 
@@ -475,7 +507,7 @@ impl<T: BeaconChainTypes> BlockLookups<T> {
         cx: &mut SyncNetworkContext<T>,
     ) {
         let (mut parent_lookup, peer_id) = if let Some((pos, peer)) = self
-            .parent_queue
+            .parent_lookups
             .iter()
             .enumerate()
             .find_map(|(pos, request)| {
@@ -483,7 +515,7 @@ impl<T: BeaconChainTypes> BlockLookups<T> {
                     .get_processing_peer(chain_hash)
                     .map(|peer| (pos, peer))
             }) {
-            (self.parent_queue.remove(pos), peer)
+            (self.parent_lookups.remove(pos), peer)
         } else {
             return debug!(self.log, "Process response for a parent lookup request that was not found"; "chain_hash" => %chain_hash);
         };
@@ -525,15 +557,15 @@ impl<T: BeaconChainTypes> BlockLookups<T> {
                         );
                     }
                 };
-                let chain_hash = parent_lookup.chain_hash();
-                let blocks = parent_lookup.chain_blocks();
+                let (chain_hash, blocks, hashes, request) = parent_lookup.parts_for_processing();
                 let process_id = ChainSegmentProcessId::ParentLookup(chain_hash);
 
                 let work = WorkEvent::chain_segment(process_id, blocks);
 
                 match beacon_processor_send.try_send(work) {
                     Ok(_) => {
-                        self.parent_queue.push(parent_lookup);
+                        self.processing_parent_lookups
+                            .insert(chain_hash, (hashes, request));
                     }
                     Err(e) => {
                         error!(
@@ -587,7 +619,7 @@ impl<T: BeaconChainTypes> BlockLookups<T> {
 
         metrics::set_gauge(
             &metrics::SYNC_PARENT_BLOCK_LOOKUPS,
-            self.parent_queue.len() as i64,
+            self.parent_lookups.len() as i64,
         );
     }
 
@@ -597,14 +629,11 @@ impl<T: BeaconChainTypes> BlockLookups<T> {
         result: BatchProcessResult,
         cx: &mut SyncNetworkContext<T>,
     ) {
-        let parent_lookup = if let Some(pos) = self
-            .parent_queue
-            .iter()
-            .position(|request| request.chain_hash() == chain_hash)
-        {
-            self.parent_queue.remove(pos)
-        } else {
-            return debug!(self.log, "Chain process response for a parent lookup request that was not found"; "chain_hash" => %chain_hash);
+        let request = match self.processing_parent_lookups.remove(&chain_hash) {
+            Some((_hashes, request)) => request,
+            None => {
+                return debug!(self.log, "Chain process response for a parent lookup request that was not found"; "chain_hash" => %chain_hash, "result" => ?result)
+            }
         };
 
         debug!(self.log, "Parent chain processed"; "chain_hash" => %chain_hash, "result" => ?result);
@@ -616,8 +645,8 @@ impl<T: BeaconChainTypes> BlockLookups<T> {
                 imported_blocks: _,
                 penalty,
             } => {
-                self.failed_chains.insert(parent_lookup.chain_hash());
-                for &peer_id in parent_lookup.used_peers() {
+                self.failed_chains.insert(chain_hash);
+                for peer_id in request.used_peers {
                     cx.report_peer(peer_id, penalty, "parent_chain_failure")
                 }
             }
@@ -628,7 +657,7 @@ impl<T: BeaconChainTypes> BlockLookups<T> {
 
         metrics::set_gauge(
             &metrics::SYNC_PARENT_BLOCK_LOOKUPS,
-            self.parent_queue.len() as i64,
+            self.parent_lookups.len() as i64,
         );
     }
 
@@ -704,14 +733,14 @@ impl<T: BeaconChainTypes> BlockLookups<T> {
             }
             Ok(_) => {
                 debug!(self.log, "Requesting parent"; &parent_lookup);
-                self.parent_queue.push(parent_lookup)
+                self.parent_lookups.push(parent_lookup)
             }
         }
 
         // We remove and add back again requests so we want this updated regardless of outcome.
         metrics::set_gauge(
             &metrics::SYNC_PARENT_BLOCK_LOOKUPS,
-            self.parent_queue.len() as i64,
+            self.parent_lookups.len() as i64,
         );
     }
 
@@ -722,6 +751,6 @@ impl<T: BeaconChainTypes> BlockLookups<T> {
 
     /// Drops all the parent chain requests and returns how many requests were dropped.
     pub fn drop_parent_chain_requests(&mut self) -> usize {
-        self.parent_queue.drain(..).len()
+        self.parent_lookups.drain(..).len()
     }
 }
diff --git a/beacon_node/network/src/sync/block_lookups/parent_lookup.rs b/beacon_node/network/src/sync/block_lookups/parent_lookup.rs
index 4a26e78fc..0e9036cee 100644
--- a/beacon_node/network/src/sync/block_lookups/parent_lookup.rs
+++ b/beacon_node/network/src/sync/block_lookups/parent_lookup.rs
@@ -25,7 +25,7 @@ pub(crate) struct ParentLookup<T: BeaconChainTypes> {
     /// The root of the block triggering this parent request.
     chain_hash: Hash256,
     /// The blocks that have currently been downloaded.
-    downloaded_blocks: Vec<BlockWrapper<T::EthSpec>>,
+    downloaded_blocks: Vec<RootBlockTuple<T::EthSpec>>,
     /// Request of the last parent.
     current_parent_request: SingleBlockRequest<PARENT_FAIL_TOLERANCE>,
     /// Id of the last parent request.
@@ -54,10 +54,10 @@ pub enum RequestError {
 }
 
 impl<T: BeaconChainTypes> ParentLookup<T> {
-    pub fn contains_block(&self, block: &SignedBeaconBlock<T::EthSpec>) -> bool {
+    pub fn contains_block(&self, block_root: &Hash256) -> bool {
         self.downloaded_blocks
             .iter()
-            .any(|d_block| d_block.block() == block)
+            .any(|(root, _d_block)| root == block_root)
     }
 
     pub fn new(block_root: Hash256, block: BlockWrapper<T::EthSpec>, peer_id: PeerId) -> Self {
@@ -65,7 +65,7 @@ impl<T: BeaconChainTypes> ParentLookup<T> {
 
         Self {
             chain_hash: block_root,
-            downloaded_blocks: vec![block],
+            downloaded_blocks: vec![(block_root, block)],
             current_parent_request,
             current_parent_request_id: None,
         }
@@ -97,7 +97,8 @@ impl<T: BeaconChainTypes> ParentLookup<T> {
 
     pub fn add_block(&mut self, block: BlockWrapper<T::EthSpec>) {
         let next_parent = block.parent_root();
-        self.downloaded_blocks.push(block);
+        let current_root = self.current_parent_request.hash;
+        self.downloaded_blocks.push((current_root, block));
         self.current_parent_request.hash = next_parent;
         self.current_parent_request.state = single_block_lookup::State::AwaitingDownload;
         self.current_parent_request_id = None;
@@ -107,6 +108,32 @@ impl<T: BeaconChainTypes> ParentLookup<T> {
         self.current_parent_request_id == Some(req_id)
     }
 
+    /// Consumes the parent request and destructures it into it's parts.
+    #[allow(clippy::type_complexity)]
+    pub fn parts_for_processing(
+        self,
+    ) -> (
+        Hash256,
+        Vec<BlockWrapper<T::EthSpec>>,
+        Vec<Hash256>,
+        SingleBlockRequest<PARENT_FAIL_TOLERANCE>,
+    ) {
+        let ParentLookup {
+            chain_hash,
+            downloaded_blocks,
+            current_parent_request,
+            current_parent_request_id: _,
+        } = self;
+        let block_count = downloaded_blocks.len();
+        let mut blocks = Vec::with_capacity(block_count);
+        let mut hashes = Vec::with_capacity(block_count);
+        for (hash, block) in downloaded_blocks {
+            blocks.push(block);
+            hashes.push(hash);
+        }
+        (chain_hash, blocks, hashes, current_parent_request)
+    }
+
     /// Get the parent lookup's chain hash.
     pub fn chain_hash(&self) -> Hash256 {
         self.chain_hash
@@ -122,10 +149,6 @@ impl<T: BeaconChainTypes> ParentLookup<T> {
         self.current_parent_request_id = None;
     }
 
-    pub fn chain_blocks(&mut self) -> Vec<BlockWrapper<T::EthSpec>> {
-        std::mem::take(&mut self.downloaded_blocks)
-    }
-
     /// Verifies that the received block is what we requested. If so, parent lookup now waits for
     /// the processing result of the block.
     pub fn verify_block(
diff --git a/beacon_node/network/src/sync/block_lookups/tests.rs b/beacon_node/network/src/sync/block_lookups/tests.rs
index 47b1830b1..06dfdcdf4 100644
--- a/beacon_node/network/src/sync/block_lookups/tests.rs
+++ b/beacon_node/network/src/sync/block_lookups/tests.rs
@@ -255,7 +255,7 @@ fn test_single_block_lookup_becomes_parent_request() {
     assert_eq!(bl.single_block_lookups.len(), 0);
     rig.expect_parent_request();
     rig.expect_empty_network();
-    assert_eq!(bl.parent_queue.len(), 1);
+    assert_eq!(bl.parent_lookups.len(), 1);
 }
 
 #[test]
@@ -283,7 +283,7 @@ fn test_parent_lookup_happy_path() {
         was_non_empty: true,
     };
     bl.parent_chain_processed(chain_hash, process_result, &mut cx);
-    assert_eq!(bl.parent_queue.len(), 0);
+    assert_eq!(bl.parent_lookups.len(), 0);
 }
 
 #[test]
@@ -320,7 +320,7 @@ fn test_parent_lookup_wrong_response() {
         was_non_empty: true,
     };
     bl.parent_chain_processed(chain_hash, process_result, &mut cx);
-    assert_eq!(bl.parent_queue.len(), 0);
+    assert_eq!(bl.parent_lookups.len(), 0);
 }
 
 #[test]
@@ -352,7 +352,7 @@ fn test_parent_lookup_empty_response() {
         was_non_empty: true,
     };
     bl.parent_chain_processed(chain_hash, process_result, &mut cx);
-    assert_eq!(bl.parent_queue.len(), 0);
+    assert_eq!(bl.parent_lookups.len(), 0);
 }
 
 #[test]
@@ -383,7 +383,7 @@ fn test_parent_lookup_rpc_failure() {
         was_non_empty: true,
     };
     bl.parent_chain_processed(chain_hash, process_result, &mut cx);
-    assert_eq!(bl.parent_queue.len(), 0);
+    assert_eq!(bl.parent_lookups.len(), 0);
 }
 
 #[test]
@@ -415,11 +415,11 @@ fn test_parent_lookup_too_many_attempts() {
             }
         }
         if i < parent_lookup::PARENT_FAIL_TOLERANCE {
-            assert_eq!(bl.parent_queue[0].failed_attempts(), dbg!(i));
+            assert_eq!(bl.parent_lookups[0].failed_attempts(), dbg!(i));
         }
     }
 
-    assert_eq!(bl.parent_queue.len(), 0);
+    assert_eq!(bl.parent_lookups.len(), 0);
 }
 
 #[test]
@@ -446,11 +446,11 @@ fn test_parent_lookup_too_many_download_attempts_no_blacklist() {
             rig.expect_penalty();
         }
         if i < parent_lookup::PARENT_FAIL_TOLERANCE {
-            assert_eq!(bl.parent_queue[0].failed_attempts(), dbg!(i));
+            assert_eq!(bl.parent_lookups[0].failed_attempts(), dbg!(i));
         }
     }
 
-    assert_eq!(bl.parent_queue.len(), 0);
+    assert_eq!(bl.parent_lookups.len(), 0);
     assert!(!bl.failed_chains.contains(&block_hash));
     assert!(!bl.failed_chains.contains(&parent.canonical_root()));
 }
@@ -487,7 +487,7 @@ fn test_parent_lookup_too_many_processing_attempts_must_blacklist() {
     }
 
     assert!(bl.failed_chains.contains(&block_hash));
-    assert_eq!(bl.parent_queue.len(), 0);
+    assert_eq!(bl.parent_lookups.len(), 0);
 }
 
 #[test]
@@ -541,7 +541,7 @@ fn test_parent_lookup_disconnection() {
         &mut cx,
     );
     bl.peer_disconnected(&peer_id, &mut cx);
-    assert!(bl.parent_queue.is_empty());
+    assert!(bl.parent_lookups.is_empty());
 }
 
 #[test]
@@ -594,5 +594,78 @@ fn test_parent_lookup_ignored_response() {
     // Return an Ignored result. The request should be dropped
     bl.parent_block_processed(chain_hash, BlockProcessResult::Ignored, &mut cx);
     rig.expect_empty_network();
-    assert_eq!(bl.parent_queue.len(), 0);
+    assert_eq!(bl.parent_lookups.len(), 0);
+}
+
+/// This is a regression test.
+#[test]
+fn test_same_chain_race_condition() {
+    let (mut bl, mut cx, mut rig) = TestRig::test_setup(Some(Level::Debug));
+
+    #[track_caller]
+    fn parent_lookups_consistency(bl: &BlockLookups<T>) {
+        let hashes: Vec<_> = bl
+            .parent_lookups
+            .iter()
+            .map(|req| req.chain_hash())
+            .collect();
+        let expected = hashes.len();
+        assert_eq!(
+            expected,
+            hashes
+                .into_iter()
+                .collect::<std::collections::HashSet<_>>()
+                .len(),
+            "duplicated chain hashes in parent queue"
+        )
+    }
+    // if we use one or two blocks it will match on the hash or the parent hash, so make a longer
+    // chain.
+    let depth = 4;
+    let mut blocks = Vec::<Arc<SignedBeaconBlock<E>>>::with_capacity(depth);
+    while blocks.len() < depth {
+        let parent = blocks
+            .last()
+            .map(|b| b.canonical_root())
+            .unwrap_or_else(Hash256::random);
+        let block = Arc::new(rig.block_with_parent(parent));
+        blocks.push(block);
+    }
+
+    let peer_id = PeerId::random();
+    let trigger_block = blocks.pop().unwrap();
+    let chain_hash = trigger_block.canonical_root();
+    bl.search_parent(chain_hash, trigger_block.clone(), peer_id, &mut cx);
+
+    for (i, block) in blocks.into_iter().rev().enumerate() {
+        let id = rig.expect_parent_request();
+        // the block
+        bl.parent_lookup_response(id, peer_id, Some(block.clone()), D, &mut cx);
+        // the stream termination
+        bl.parent_lookup_response(id, peer_id, None, D, &mut cx);
+        // the processing request
+        rig.expect_block_process();
+        // the processing result
+        if i + 2 == depth {
+            // one block was removed
+            bl.parent_block_processed(chain_hash, BlockError::BlockIsAlreadyKnown.into(), &mut cx)
+        } else {
+            bl.parent_block_processed(chain_hash, BlockError::ParentUnknown(block).into(), &mut cx)
+        }
+        parent_lookups_consistency(&bl)
+    }
+
+    // Processing succeeds, now the rest of the chain should be sent for processing.
+    rig.expect_parent_chain_process();
+
+    // Try to get this block again while the chain is being processed. We should not request it again.
+    let peer_id = PeerId::random();
+    bl.search_parent(chain_hash, trigger_block, peer_id, &mut cx);
+    parent_lookups_consistency(&bl);
+
+    let process_result = BatchProcessResult::Success {
+        was_non_empty: true,
+    };
+    bl.parent_chain_processed(chain_hash, process_result, &mut cx);
+    assert_eq!(bl.parent_lookups.len(), 0);
 }
diff --git a/beacon_node/network/src/sync/manager.rs b/beacon_node/network/src/sync/manager.rs
index 9a072f430..67efa3163 100644
--- a/beacon_node/network/src/sync/manager.rs
+++ b/beacon_node/network/src/sync/manager.rs
@@ -710,7 +710,7 @@ impl<T: BeaconChainTypes> SyncManager<T> {
 
                 // Some logs.
                 if dropped_single_blocks_requests > 0 || dropped_parent_chain_requests > 0 {
-                    debug!(self.log, "Execution engine not online, dropping active requests.";
+                    debug!(self.log, "Execution engine not online. Dropping active requests.";
                         "dropped_single_blocks_requests" => dropped_single_blocks_requests,
                         "dropped_parent_chain_requests" => dropped_parent_chain_requests,
                     );
diff --git a/beacon_node/network/src/sync/network_context.rs b/beacon_node/network/src/sync/network_context.rs
index adefb89dd..d7d48be74 100644
--- a/beacon_node/network/src/sync/network_context.rs
+++ b/beacon_node/network/src/sync/network_context.rs
@@ -525,7 +525,7 @@ impl<T: BeaconChainTypes> SyncNetworkContext<T> {
                 source: ReportSource::SyncService,
             })
             .unwrap_or_else(|_| {
-                warn!(self.log, "Could not report peer, channel failed");
+                warn!(self.log, "Could not report peer: channel failed");
             });
     }
 
@@ -540,7 +540,7 @@ impl<T: BeaconChainTypes> SyncNetworkContext<T> {
                 msg,
             })
             .unwrap_or_else(|e| {
-                warn!(self.log, "Could not report peer, channel failed"; "error"=> %e);
+                warn!(self.log, "Could not report peer: channel failed"; "error"=> %e);
             });
     }
 
diff --git a/beacon_node/src/cli.rs b/beacon_node/src/cli.rs
index 24bc06c7b..f1180e3f9 100644
--- a/beacon_node/src/cli.rs
+++ b/beacon_node/src/cli.rs
@@ -725,6 +725,14 @@ pub fn cli_app<'a, 'b>() -> App<'a, 'b> {
                 .takes_value(true)
                 .conflicts_with("checkpoint-state")
         )
+        .arg(
+            Arg::with_name("checkpoint-sync-url-timeout")
+                .long("checkpoint-sync-url-timeout")
+                .help("Set the timeout for checkpoint sync calls to remote beacon node HTTP endpoint.")
+                .value_name("SECONDS")
+                .takes_value(true)
+                .default_value("60")
+        )
         .arg(
             Arg::with_name("reconstruct-historic-states")
                 .long("reconstruct-historic-states")
@@ -871,4 +879,19 @@ pub fn cli_app<'a, 'b>() -> App<'a, 'b> {
                       Useful if you intend to run a non-validating beacon node.")
                 .takes_value(false)
         )
+        .arg(
+            Arg::with_name("light-client-server")
+                .long("light-client-server")
+                .help("Act as a full node supporting light clients on the p2p network \
+                       [experimental]")
+                .takes_value(false)
+        )
+        .arg(
+            Arg::with_name("gui")
+                .long("gui")
+                .hidden(true)
+                .help("Enable the graphical user interface and all its requirements. \
+                      This is equivalent to --http and --validator-monitor-auto.")
+                .takes_value(false)
+        )
 }
diff --git a/beacon_node/src/config.rs b/beacon_node/src/config.rs
index af33fdf28..66333a7ed 100644
--- a/beacon_node/src/config.rs
+++ b/beacon_node/src/config.rs
@@ -14,6 +14,7 @@ use std::cmp::max;
 use std::fmt::Debug;
 use std::fmt::Write;
 use std::fs;
+use std::net::Ipv6Addr;
 use std::net::{IpAddr, Ipv4Addr, ToSocketAddrs};
 use std::path::{Path, PathBuf};
 use std::str::FromStr;
@@ -34,13 +35,13 @@ pub fn get_config<E: EthSpec>(
     let spec = &context.eth2_config.spec;
     let log = context.log();
 
-    let mut client_config = ClientConfig {
-        data_dir: get_data_dir(cli_args),
-        ..Default::default()
-    };
+    let mut client_config = ClientConfig::default();
+
+    // Update the client's data directory
+    client_config.set_data_dir(get_data_dir(cli_args));
 
     // If necessary, remove any existing database and configuration
-    if client_config.data_dir.exists() && cli_args.is_present("purge-db") {
+    if client_config.data_dir().exists() && cli_args.is_present("purge-db") {
         // Remove the chain_db.
         let chain_db = client_config.get_db_path();
         if chain_db.exists() {
@@ -57,11 +58,11 @@ pub fn get_config<E: EthSpec>(
     }
 
     // Create `datadir` and any non-existing parent directories.
-    fs::create_dir_all(&client_config.data_dir)
+    fs::create_dir_all(client_config.data_dir())
         .map_err(|e| format!("Failed to create data dir: {}", e))?;
 
     // logs the chosen data directory
-    let mut log_dir = client_config.data_dir.clone();
+    let mut log_dir = client_config.data_dir().clone();
     // remove /beacon from the end
     log_dir.pop();
     info!(log, "Data directory initialised"; "datadir" => log_dir.into_os_string().into_string().expect("Datadir should be a valid os string"));
@@ -69,10 +70,13 @@ pub fn get_config<E: EthSpec>(
     /*
      * Networking
      */
+
+    let data_dir_ref = client_config.data_dir().clone();
+
     set_network_config(
         &mut client_config.network,
         cli_args,
-        &client_config.data_dir,
+        &data_dir_ref,
         log,
         false,
     )?;
@@ -303,7 +307,7 @@ pub fn get_config<E: EthSpec>(
         } else if let Some(jwt_secret_key) = cli_args.value_of("execution-jwt-secret-key") {
             use std::fs::File;
             use std::io::Write;
-            secret_file = client_config.data_dir.join(DEFAULT_JWT_FILE);
+            secret_file = client_config.data_dir().join(DEFAULT_JWT_FILE);
             let mut jwt_secret_key_file = File::create(secret_file.clone())
                 .map_err(|e| format!("Error while creating jwt_secret_key file: {:?}", e))?;
             jwt_secret_key_file
@@ -332,7 +336,7 @@ pub fn get_config<E: EthSpec>(
             clap_utils::parse_optional(cli_args, "suggested-fee-recipient")?;
         el_config.jwt_id = clap_utils::parse_optional(cli_args, "execution-jwt-id")?;
         el_config.jwt_version = clap_utils::parse_optional(cli_args, "execution-jwt-version")?;
-        el_config.default_datadir = client_config.data_dir.clone();
+        el_config.default_datadir = client_config.data_dir().clone();
         el_config.builder_profit_threshold =
             clap_utils::parse_required(cli_args, "builder-profit-threshold")?;
         let execution_timeout_multiplier =
@@ -446,6 +450,8 @@ pub fn get_config<E: EthSpec>(
                 .extend_from_slice(boot_nodes)
         }
     }
+    client_config.chain.checkpoint_sync_url_timeout =
+        clap_utils::parse_required::<u64>(cli_args, "checkpoint-sync-url-timeout")?;
 
     client_config.genesis = if let Some(genesis_state_bytes) =
         eth2_network_config.genesis_state_bytes.clone()
@@ -576,7 +582,7 @@ pub fn get_config<E: EthSpec>(
         let slasher_dir = if let Some(slasher_dir) = cli_args.value_of("slasher-dir") {
             PathBuf::from(slasher_dir)
         } else {
-            client_config.data_dir.join("slasher_db")
+            client_config.data_dir().join("slasher_db")
         };
 
         let mut slasher_config = slasher::Config::new(slasher_dir);
@@ -708,6 +714,12 @@ pub fn get_config<E: EthSpec>(
     client_config.chain.builder_fallback_disable_checks =
         cli_args.is_present("builder-fallback-disable-checks");
 
+    // Graphical user interface config.
+    if cli_args.is_present("gui") {
+        client_config.http_api.enabled = true;
+        client_config.validator_monitor_auto = true;
+    }
+
     Ok(client_config)
 }
 
@@ -837,9 +849,11 @@ pub fn set_network_config(
     }
 
     if cli_args.is_present("enr-match") {
-        // set the enr address to localhost if the address is 0.0.0.0
-        if config.listen_address == "0.0.0.0".parse::<IpAddr>().expect("valid ip addr") {
-            config.enr_address = Some("127.0.0.1".parse::<IpAddr>().expect("valid ip addr"));
+        // set the enr address to localhost if the address is unspecified
+        if config.listen_address == IpAddr::V4(Ipv4Addr::UNSPECIFIED) {
+            config.enr_address = Some(IpAddr::V4(Ipv4Addr::LOCALHOST));
+        } else if config.listen_address == IpAddr::V6(Ipv6Addr::UNSPECIFIED) {
+            config.enr_address = Some(IpAddr::V6(Ipv6Addr::LOCALHOST));
         } else {
             config.enr_address = Some(config.listen_address);
         }
@@ -919,6 +933,9 @@ pub fn set_network_config(
         config.discv5_config.table_filter = |_| true;
     }
 
+    // Light client server config.
+    config.enable_light_client_server = cli_args.is_present("light-client-server");
+
     Ok(())
 }
 
diff --git a/beacon_node/store/src/errors.rs b/beacon_node/store/src/errors.rs
index bbcc043e7..8a0b44197 100644
--- a/beacon_node/store/src/errors.rs
+++ b/beacon_node/store/src/errors.rs
@@ -3,7 +3,7 @@ use crate::config::StoreConfigError;
 use crate::hot_cold_store::HotColdDBError;
 use ssz::DecodeError;
 use state_processing::BlockReplayError;
-use types::{BeaconStateError, Hash256, Slot};
+use types::{BeaconStateError, Hash256, InconsistentFork, Slot};
 
 pub type Result<T> = std::result::Result<T, Error>;
 
@@ -47,6 +47,7 @@ pub enum Error {
     ResyncRequiredForExecutionPayloadSeparation,
     SlotClockUnavailableForMigration,
     V9MigrationFailure(Hash256),
+    InconsistentFork(InconsistentFork),
 }
 
 pub trait HandleUnavailable<T> {
@@ -105,6 +106,12 @@ impl From<BlockReplayError> for Error {
     }
 }
 
+impl From<InconsistentFork> for Error {
+    fn from(e: InconsistentFork) -> Error {
+        Error::InconsistentFork(e)
+    }
+}
+
 #[derive(Debug)]
 pub struct DBError {
     pub message: String,
diff --git a/beacon_node/store/src/hot_cold_store.rs b/beacon_node/store/src/hot_cold_store.rs
index 3df7d337e..af8c4647c 100644
--- a/beacon_node/store/src/hot_cold_store.rs
+++ b/beacon_node/store/src/hot_cold_store.rs
@@ -362,7 +362,8 @@ impl<E: EthSpec, Hot: ItemStore<E>, Cold: ItemStore<E>> HotColdDB<E, Hot, Cold>
         } else if !self.config.prune_payloads {
             // If payload pruning is disabled there's a chance we may have the payload of
             // this finalized block. Attempt to load it but don't error in case it's missing.
-            if let Some(payload) = self.get_execution_payload(block_root)? {
+            let fork_name = blinded_block.fork_name(&self.spec)?;
+            if let Some(payload) = self.get_execution_payload(block_root, fork_name)? {
                 DatabaseBlock::Full(
                     blinded_block
                         .try_into_full_block(Some(payload))
@@ -411,8 +412,9 @@ impl<E: EthSpec, Hot: ItemStore<E>, Cold: ItemStore<E>> HotColdDB<E, Hot, Cold>
         blinded_block: SignedBeaconBlock<E, BlindedPayload<E>>,
     ) -> Result<SignedBeaconBlock<E>, Error> {
         if blinded_block.message().execution_payload().is_ok() {
+            let fork_name = blinded_block.fork_name(&self.spec)?;
             let execution_payload = self
-                .get_execution_payload(block_root)?
+                .get_execution_payload(block_root, fork_name)?
                 .ok_or(HotColdDBError::MissingExecutionPayload(*block_root))?;
             blinded_block.try_into_full_block(Some(execution_payload))
         } else {
@@ -455,9 +457,26 @@ impl<E: EthSpec, Hot: ItemStore<E>, Cold: ItemStore<E>> HotColdDB<E, Hot, Cold>
     }
 
     /// Load the execution payload for a block from disk.
+    /// This method deserializes with the proper fork.
     pub fn get_execution_payload(
         &self,
         block_root: &Hash256,
+        fork_name: ForkName,
+    ) -> Result<Option<ExecutionPayload<E>>, Error> {
+        let column = ExecutionPayload::<E>::db_column().into();
+        let key = block_root.as_bytes();
+
+        match self.hot_db.get_bytes(column, key)? {
+            Some(bytes) => Ok(Some(ExecutionPayload::from_ssz_bytes(&bytes, fork_name)?)),
+            None => Ok(None),
+        }
+    }
+
+    /// Load the execution payload for a block from disk.
+    /// DANGEROUS: this method just guesses the fork.
+    pub fn get_execution_payload_dangerous_fork_agnostic(
+        &self,
+        block_root: &Hash256,
     ) -> Result<Option<ExecutionPayload<E>>, Error> {
         self.get_item(block_root)
     }
diff --git a/book/src/SUMMARY.md b/book/src/SUMMARY.md
index d05677465..a43fa10e6 100644
--- a/book/src/SUMMARY.md
+++ b/book/src/SUMMARY.md
@@ -1,9 +1,6 @@
 # Summary
 
 * [Introduction](./intro.md)
-* [Become a Validator](./mainnet-validator.md)
-    * [Become a Testnet Validator](./testnet-validator.md)
-* [Merge Migration](./merge-migration.md)
 * [Installation](./installation.md)
     * [System Requirements](./system-requirements.md)
     * [Pre-Built Binaries](./installation-binaries.md)
@@ -13,6 +10,9 @@
     * [Cross-Compiling](./cross-compiling.md)
     * [Homebrew](./homebrew.md)
     * [Update Priorities](./installation-priorities.md)
+* [Run a Node](./run_a_node.md)
+* [Become a Validator](./mainnet-validator.md)
+    * [Become a Testnet Validator](./testnet-validator.md)
 * [Key Management](./key-management.md)
     * [Create a wallet](./wallet-create.md)
     * [Create a validator](./validator-create.md)
@@ -46,6 +46,7 @@
     * [Pre-Releases](./advanced-pre-releases.md)
     * [Release Candidates](./advanced-release-candidates.md)
     * [MEV and Lighthouse](./builders.md)
+    * [Merge Migration](./merge-migration.md)
 * [Contributing](./contributing.md)
     * [Development Environment](./setup.md)
 * [FAQs](./faq.md)
diff --git a/book/src/api-lighthouse.md b/book/src/api-lighthouse.md
index d9c8080b4..c1ba6a2dc 100644
--- a/book/src/api-lighthouse.md
+++ b/book/src/api-lighthouse.md
@@ -62,6 +62,43 @@ curl -X GET "http://localhost:5052/lighthouse/health" -H  "accept: application/j
 
 ```
 
+### `/lighthouse/ui/health`
+
+
+```bash
+curl -X GET "http://localhost:5052/lighthouse/ui/health" -H  "accept: application/json" | jq
+```
+
+```json
+{
+  "data": {
+    "total_memory": 16443219968,
+    "free_memory": 1283739648,
+    "used_memory": 5586264064,
+    "sys_loadavg_1": 0.59,
+    "sys_loadavg_5": 1.13,
+    "sys_loadavg_15": 2.41,
+    "cpu_cores": 4,
+    "cpu_threads": 8,
+    "global_cpu_frequency": 3.4,
+    "disk_bytes_total": 502390845440,
+    "disk_bytes_free": 9981386752,
+    "network_name": "wlp0s20f3",
+    "network_bytes_total_received": 14105556611,
+    "network_bytes_total_transmit": 3649489389,
+    "nat_open": true,
+    "connected_peers": 80,
+    "sync_state": "Synced",
+    "system_uptime": 660706,
+    "app_uptime": 105,
+    "system_name": "Arch Linux",
+    "kernel_version": "5.19.13-arch1-1",
+    "os_version": "Linux rolling Arch Linux",
+    "host_name": "Computer1"
+  }
+}
+```
+
 ### `/lighthouse/syncing`
 
 ```bash
diff --git a/book/src/api-vc-endpoints.md b/book/src/api-vc-endpoints.md
index 9aedf6e24..76cffc0e4 100644
--- a/book/src/api-vc-endpoints.md
+++ b/book/src/api-vc-endpoints.md
@@ -6,6 +6,7 @@ HTTP Path | Description |
 | --- | -- |
 [`GET /lighthouse/version`](#get-lighthouseversion) | Get the Lighthouse software version.
 [`GET /lighthouse/health`](#get-lighthousehealth) | Get information about the host machine.
+[`GET /lighthouse/ui/health`](#get-lighthouseuihealth) | Get information about the host machine. Focused for UI applications.
 [`GET /lighthouse/spec`](#get-lighthousespec) | Get the Ethereum proof-of-stake consensus specification used by the validator.
 [`GET /lighthouse/auth`](#get-lighthouseauth) | Get the location of the authorization token.
 [`GET /lighthouse/validators`](#get-lighthousevalidators) | List all validators.
@@ -77,6 +78,45 @@ Returns information regarding the health of the host machine.
 }
 ```
 
+## `GET /lighthouse/ui/health`
+
+Returns information regarding the health of the host machine.
+
+### HTTP Specification
+
+| Property          | Specification                              |
+|-------------------|--------------------------------------------|
+| Path              | `/lighthouse/ui/health`                       |
+| Method            | GET                                        |
+| Required Headers  | [`Authorization`](./api-vc-auth-header.md) |
+| Typical Responses | 200                                        |
+
+### Example Response Body
+
+```json
+{
+  "data": {
+    "total_memory": 16443219968,
+    "free_memory": 1283739648,
+    "used_memory": 5586264064,
+    "sys_loadavg_1": 0.59,
+    "sys_loadavg_5": 1.13,
+    "sys_loadavg_15": 2.41,
+    "cpu_cores": 4,
+    "cpu_threads": 8,
+    "global_cpu_frequency": 3.4,
+    "disk_bytes_total": 502390845440,
+    "disk_bytes_free": 9981386752,
+    "system_uptime": 660706,
+    "app_uptime": 105,
+    "system_name": "Arch Linux",
+    "kernel_version": "5.19.13-arch1-1",
+    "os_version": "Linux rolling Arch Linux",
+    "host_name": "Computer1"
+  }
+}
+```
+
 ## `GET /lighthouse/spec`
 
 Returns the Ethereum proof-of-stake consensus specification loaded for this validator.
diff --git a/book/src/database-migrations.md b/book/src/database-migrations.md
index c31e373b4..2b0ac836a 100644
--- a/book/src/database-migrations.md
+++ b/book/src/database-migrations.md
@@ -24,6 +24,8 @@ validator client or the slasher**.
 | v2.5.0             | Aug 2022     | v11            | yes                  |
 | v3.0.0             | Aug 2022     | v11            | yes                  |
 | v3.1.0             | Sep 2022     | v12            | yes                  |
+| v3.2.0             | Oct 2022     | v12            | yes                  |
+| v3.3.0             | TBD          | v13            | yes                  |
 
 > **Note**: All point releases (e.g. v2.3.1) are schema-compatible with the prior minor release
 > (e.g. v2.3.0).
diff --git a/book/src/intro.md b/book/src/intro.md
index fca075892..ef16913d6 100644
--- a/book/src/intro.md
+++ b/book/src/intro.md
@@ -18,6 +18,7 @@ We implement the specification as defined in the
 You may read this book from start to finish, or jump to some of these topics:
 
 - Follow the [Installation Guide](./installation.md) to install Lighthouse.
+- Run your very [own beacon node](./run_a_node.md).
 - Learn about [becoming a mainnet validator](./mainnet-validator.md).
 - Get hacking with the [Development Environment Guide](./setup.md).
 - Utilize the whole stack by starting a [local testnet](./setup.md#local-testnets).
diff --git a/book/src/merge-migration.md b/book/src/merge-migration.md
index 8596cd942..08f1b51e4 100644
--- a/book/src/merge-migration.md
+++ b/book/src/merge-migration.md
@@ -1,9 +1,8 @@
 # Merge Migration
 
-This document provides detail for users who want to run a merge-ready Lighthouse node.
+This document provides detail for users who want to run a Lighthouse node on post-merge Ethereum.
 
-> The merge is occurring on mainnet in September. You _must_ have a merge-ready setup by September 6
-> 2022.
+> The merge occurred on mainnet in September 2022.
 
 ## Necessary Configuration
 
@@ -27,12 +26,9 @@ engine to a merge-ready version.
 You must configure your node to be merge-ready before the Bellatrix fork occurs on the network
 on which your node is operating.
 
-* **Mainnet**: the Bellatrix fork is scheduled for epoch 144896, September 6 2022 11:34 UTC.
-  You must ensure your node configuration is updated before then in order to continue following
-  the chain. We recommend updating your configuration now.
-
-* **Goerli (Prater)**, **Ropsten**, **Sepolia**, **Kiln**: the Bellatrix fork has already occurred.
-  You must have a merge-ready configuration right now.
+* **Gnosis**: the Bellatrix fork has not yet been scheduled.
+* **Mainnet**, **Goerli (Prater)**, **Ropsten**, **Sepolia**, **Kiln**: the Bellatrix fork has
+  already occurred. You must have a merge-ready configuration right now.
 
 ## Connecting to an execution engine
 
@@ -65,6 +61,7 @@ the relevant page for your execution engine for the required flags:
 - [Geth: Connecting to Consensus Clients](https://geth.ethereum.org/docs/interface/consensus-clients)
 - [Nethermind: Running Nethermind Post Merge](https://docs.nethermind.io/nethermind/first-steps-with-nethermind/running-nethermind-post-merge)
 - [Besu: Prepare For The Merge](https://besu.hyperledger.org/en/stable/HowTo/Upgrade/Prepare-for-The-Merge/)
+- [Erigon: Beacon Chain (Consensus Layer)](https://github.com/ledgerwatch/erigon#beacon-chain-consensus-layer)
 
 Once you have configured your execution engine to open up the engine API (usually on port 8551) you
 should add the URL to your `lighthouse bn` flags with `--execution-endpoint <URL>`, as well as
diff --git a/book/src/redundancy.md b/book/src/redundancy.md
index dae7ac51f..dcd2ecdea 100644
--- a/book/src/redundancy.md
+++ b/book/src/redundancy.md
@@ -55,42 +55,27 @@ In our previous example, we listed `http://192.168.1.1:5052` as a redundant
 node. Apart from having sufficient resources, the backup node should have the
 following flags:
 
-- `--staking`: starts the HTTP API server and ensures the execution chain is synced.
+- `--http`: starts the HTTP API server.
 - `--http-address 0.0.0.0`: this allows *any* external IP address to access the
 	HTTP server (a firewall should be configured to deny unauthorized access to port
 	`5052`). This is only required if your backup node is on a different host.
-- `--subscribe-all-subnets`: ensures that the beacon node subscribes to *all*
-	subnets, not just on-demand requests from validators.
-- `--import-all-attestations`: ensures that the beacon node performs
-	aggregation on all seen attestations.
+- `--execution-endpoint`: see [Merge Migration](./merge-migration.md).
+- `--execution-jwt`: see [Merge Migration](./merge-migration.md).
 
-Subsequently, one could use the following command to provide a backup beacon
-node:
+For example one could use the following command to provide a backup beacon node:
 
 ```bash
 lighthouse bn \
-  --staking \
+  --http \
   --http-address 0.0.0.0 \
-  --subscribe-all-subnets \
-  --import-all-attestations
+  --execution-endpoint http://localhost:8551 \
+  --execution-jwt /secrets/jwt.hex
 ```
 
-### Resource usage of redundant Beacon Nodes
-
-The `--subscribe-all-subnets` and `--import-all-attestations` flags typically
-cause a significant increase in resource consumption. A doubling in CPU
-utilization and RAM consumption is expected.
-
-The increase in resource consumption is due to the fact that the beacon node is
-now processing, validating, aggregating and forwarding *all* attestations,
-whereas previously it was likely only doing a fraction of this work. Without
-these flags, subscription to attestation subnets and aggregation of
-attestations is only performed for validators which [explicitly request
-subscriptions][subscribe-api].
-
-There are 64 subnets and each validator will result in a subscription to *at
-least* one subnet. So, using the two aforementioned flags will result in
-resource consumption akin to running 64+ validators.
+Prior to v3.2.0 fallback beacon nodes also required the `--subscribe-all-subnets` and
+`--import-all-attestations` flags. These flags are no longer required as the validator client will
+now broadcast subscriptions to all connected beacon nodes by default. This broadcast behaviour
+can be disabled using the `--disable-run-on-all` flag for `lighthouse vc`.
 
 ## Redundant execution nodes
 
diff --git a/book/src/run_a_node.md b/book/src/run_a_node.md
new file mode 100644
index 000000000..5ce42aa63
--- /dev/null
+++ b/book/src/run_a_node.md
@@ -0,0 +1,171 @@
+# Run a Node
+
+This document provides detail for users who want to run a Lighthouse beacon node.
+You should be finished with one [Installation](./installation.md) method of your choice to continue with the following steps:
+
+1. Set up an [execution node](#step-1-set-up-an-execution-node);
+1. Enable [checkpoint sync](#step-2-choose-a-checkpoint-sync-provider);
+1. Run [Lighthouse](#step-3-run-lighthouse);
+1. [Check logs](#step-4-check-logs); and
+1. [Further readings](#step-5-further-readings).
+
+Checkpoint sync is *optional*; however, we recommend it since it is substantially faster
+than syncing from genesis while still providing the same functionality.
+
+## Step 1: Set up an execution node
+
+The Lighthouse beacon node *must* connect to an execution engine in order to validate the transactions
+present in blocks. Two flags are used to configure this connection:
+
+- `--execution-endpoint`: the *URL* of the execution engine API. Often this will be
+  `http://localhost:8551`.
+- `--execution-jwt`: the *path* to the file containing the JWT secret shared by Lighthouse and the
+  execution engine. This is a mandatory form of authentication that ensures that Lighthouse
+has authority to control the execution engine.
+
+Each execution engine has its own flags for configuring the engine API and JWT.
+Please consult the relevant page of your execution engine for the required flags:
+
+- [Geth: Connecting to Consensus Clients](https://geth.ethereum.org/docs/interface/consensus-clients)
+- [Nethermind: Running Nethermind & CL](https://docs.nethermind.io/nethermind/first-steps-with-nethermind/running-nethermind-post-merge)
+- [Besu: Connect to Mainnet](https://besu.hyperledger.org/en/stable/public-networks/get-started/connect/mainnet/)
+- [Erigon: Beacon Chain (Consensus Layer)](https://github.com/ledgerwatch/erigon#beacon-chain-consensus-layer)
+
+The execution engine connection must be *exclusive*, i.e. you must have one execution node
+per beacon node. The reason for this is that the beacon node _controls_ the execution node.
+
+## Step 2: Choose a checkpoint sync provider
+
+Lighthouse supports fast sync from a recent finalized checkpoint.
+The checkpoint sync is done using a [public endpoint](#use-a-community-checkpoint-sync-endpoint)
+provided by the Ethereum community.
+
+In [step 3](#step-3-run-lighthouse), when running Lighthouse,
+we will enable checkpoint sync by providing the URL to the `--checkpoint-sync-url` flag.
+
+### Use a community checkpoint sync endpoint
+
+The Ethereum community provides various [public endpoints](https://eth-clients.github.io/checkpoint-sync-endpoints/) for you to choose from for your initial checkpoint state. Select one for your network and use it as the URL.
+
+For example, the URL for Sigma Prime's checkpoint sync server for mainnet is `https://mainnet.checkpoint.sigp.io`,
+which we will use in [step 3](#step-3-run-lighthouse).
+
+## Step 3: Run Lighthouse
+
+To run Lighthouse, we use the three flags from the steps above:
+- `--execution-endpoint`;
+- `--execution-jwt`; and
+- `--checkpoint-sync-url`.
+
+Additionally, we run Lighthouse with the `--network` flag, which selects a network:
+
+- `lighthouse` (no flag): Mainnet.
+- `lighthouse --network mainnet`: Mainnet.
+- `lighthouse --network goerli`: Goerli (testnet).
+
+Using the correct `--network` flag is very important; using the wrong flag can
+result in penalties, slashings or lost deposits. As a rule of thumb, *always*
+provide a `--network` flag instead of relying on the default.
+
+For the testnets we support [Goerli](https://goerli.net/) (`--network goerli`),
+[Sepolia](https://sepolia.dev/) (`--network sepolia`), and [Gnosis chain](https://www.gnosis.io/) (`--network gnosis`).
+
+Minor modifications depend on if you want to run your node while [staking](#staking) or [non-staking](#non-staking).
+In the following, we will provide examples of what a Lighthouse setup could look like.
+
+### Staking
+
+```
+lighthouse bn \
+  --network mainnet \
+  --execution-endpoint http://localhost:8551 \
+  --execution-jwt /secrets/jwt.hex \
+  --checkpoint-sync-url https://mainnet.checkpoint.sigp.io \
+  --http
+```
+
+A Lighthouse beacon node can be configured to expose an HTTP server by supplying the `--http` flag.
+The default listen address is `127.0.0.1:5052`.
+The HTTP API is required for the beacon node to accept connections from the *validator client*, which manages keys.
+
+### Non-staking
+
+``` 
+lighthouse bn \
+  --network mainnet \
+  --execution-endpoint http://localhost:8551 \
+  --execution-jwt /secrets/jwt.hex \
+  --checkpoint-sync-url https://mainnet.checkpoint.sigp.io \
+  --disable-deposit-contract-sync
+```
+
+Since we are not staking, we can use the `--disable-deposit-contract-sync` flag.
+
+---
+
+Once Lighthouse runs, we can monitor the logs to see if it is syncing correctly.
+
+## Step 4: Check logs
+Several logs help you identify if Lighthouse is running correctly. 
+
+### Logs - Checkpoint sync
+Lighthouse will print a message to indicate that checkpoint sync is being used:
+
+```
+INFO Starting checkpoint sync                remote_url: http://remote-bn:8000/, service: beacon
+```
+
+After a short time (usually less than a minute), it will log the details of the checkpoint
+loaded from the remote beacon node:
+
+```
+INFO Loaded checkpoint block and state       state_root: 0xe8252c68784a8d5cc7e5429b0e95747032dd1dcee0d1dc9bdaf6380bf90bc8a6, block_root: 0x5508a20147299b1a7fe9dbea1a8b3bf979f74c52e7242039bd77cbff62c0695a, slot: 2034720, service: beacon
+```
+
+Once the checkpoint is loaded Lighthouse will sync forwards to the head of the chain.
+
+If a validator client is connected to the node then it will be able to start completing its duties
+as soon as forwards sync completes.
+
+> **Security Note**: You should cross-reference the `block_root` and `slot` of the loaded checkpoint
+> against a trusted source like another [public endpoint](https://eth-clients.github.io/checkpoint-sync-endpoints/),
+> a friend's node, or a block explorer.
+
+#### Backfilling Blocks
+
+Once forwards sync completes, Lighthouse will commence a "backfill sync" to download the blocks
+from the checkpoint back to genesis.
+
+The beacon node will log messages similar to the following each minute while it completes backfill
+sync:
+
+```
+INFO Downloading historical blocks  est_time: 5 hrs 0 mins, speed: 111.96 slots/sec, distance: 2020451 slots (40 weeks 0 days), service: slot_notifier
+```
+
+Once backfill is complete, a `INFO Historical block download complete` log will be emitted.
+
+Check out the [FAQ](./checkpoint-sync.md#faq) for more information on checkpoint sync.
+
+### Logs - Syncing
+
+You should see that Lighthouse remains in sync and marks blocks
+as `verified` indicating that they have been processed successfully by the execution engine:
+
+```
+INFO Synced, slot: 3690668, block: 0x1244…cb92, epoch: 115333, finalized_epoch: 115331, finalized_root: 0x0764…2a3d, exec_hash: 0x929c…1ff6 (verified), peers: 78
+```
+
+
+## Step 5: Further readings
+
+Several other resources are the next logical step to explore after running your beacon node: 
+
+- Learn how to [become a validator](./mainnet-validator.md);
+- Explore how to [manage your keys](./key-management.md);
+- Research on [validator management](./validator-management.md);
+- Dig into the [APIs](./api.md) that the beacon node and validator client provide;
+- Study even more about [checkpoint sync](./checkpoint-sync.md); or
+- Investigate what steps had to be taken in the past to execute a smooth [merge migration](./merge-migration.md).
+
+Finally, if you a struggling with anything, join our [Discord](https://discord.gg/cyAszAh). We are happy to help!
\ No newline at end of file
diff --git a/boot_node/Cargo.toml b/boot_node/Cargo.toml
index 4f4c18ac8..1dedabe4a 100644
--- a/boot_node/Cargo.toml
+++ b/boot_node/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "boot_node"
-version = "3.2.1"
+version = "3.3.0"
 authors = ["Sigma Prime <contact@sigmaprime.io>"]
 edition = "2021"
 
diff --git a/boot_node/src/config.rs b/boot_node/src/config.rs
index 4df7a5f23..b7a66cbbd 100644
--- a/boot_node/src/config.rs
+++ b/boot_node/src/config.rs
@@ -1,9 +1,11 @@
 use beacon_node::{get_data_dir, set_network_config};
 use clap::ArgMatches;
 use eth2_network_config::Eth2NetworkConfig;
+use lighthouse_network::discv5::enr::EnrBuilder;
+use lighthouse_network::discv5::IpMode;
 use lighthouse_network::discv5::{enr::CombinedKey, Discv5Config, Enr};
 use lighthouse_network::{
-    discovery::{create_enr_builder_from_config, load_enr_from_disk, use_or_load_enr},
+    discovery::{load_enr_from_disk, use_or_load_enr},
     load_private_key, CombinedKeyExt, NetworkConfig,
 };
 use serde_derive::{Deserialize, Serialize};
@@ -70,6 +72,15 @@ impl<T: EthSpec> BootNodeConfig<T> {
         // the address to listen on
         let listen_socket =
             SocketAddr::new(network_config.listen_address, network_config.discovery_port);
+        if listen_socket.is_ipv6() {
+            // create ipv6 sockets and enable ipv4 mapped addresses.
+            network_config.discv5_config.ip_mode = IpMode::Ip6 {
+                enable_mapped_addresses: true,
+            };
+        } else {
+            // Set explicitly as ipv4 otherwise
+            network_config.discv5_config.ip_mode = IpMode::Ip4;
+        }
 
         let private_key = load_private_key(&network_config, &logger);
         let local_key = CombinedKey::from_libp2p(&private_key)?;
@@ -104,7 +115,29 @@ impl<T: EthSpec> BootNodeConfig<T> {
             // Build the local ENR
 
             let mut local_enr = {
-                let mut builder = create_enr_builder_from_config(&network_config, false);
+                let mut builder = EnrBuilder::new("v4");
+                // Set the enr address if specified. Set also the port.
+                // NOTE: if the port is specified but the the address is not, the port won't be
+                // set since it can't be known if it's an ipv6 or ipv4 udp port.
+                if let Some(enr_address) = network_config.enr_address {
+                    match enr_address {
+                        std::net::IpAddr::V4(ipv4_addr) => {
+                            builder.ip4(ipv4_addr);
+                            if let Some(port) = network_config.enr_udp_port {
+                                builder.udp4(port);
+                            }
+                        }
+                        std::net::IpAddr::V6(ipv6_addr) => {
+                            builder.ip6(ipv6_addr);
+                            if let Some(port) = network_config.enr_udp_port {
+                                builder.udp6(port);
+                                // We are enabling mapped addresses in the boot node in this case,
+                                // so advertise an udp4 port as well.
+                                builder.udp4(port);
+                            }
+                        }
+                    }
+                };
 
                 // If we know of the ENR field, add it to the initial construction
                 if let Some(enr_fork_bytes) = enr_fork {
diff --git a/boot_node/src/server.rs b/boot_node/src/server.rs
index c4bf887e9..8f38fb300 100644
--- a/boot_node/src/server.rs
+++ b/boot_node/src/server.rs
@@ -9,53 +9,63 @@ use slog::info;
 use types::EthSpec;
 
 pub async fn run<T: EthSpec>(config: BootNodeConfig<T>, log: slog::Logger) {
+    let BootNodeConfig {
+        listen_socket,
+        boot_nodes,
+        local_enr,
+        local_key,
+        discv5_config,
+        ..
+    } = config;
+
     // Print out useful information about the generated ENR
 
-    let enr_socket = config
-        .local_enr
-        .udp4_socket()
-        .expect("Enr has a UDP socket");
-    let eth2_field = config
-        .local_enr
+    let enr_v4_socket = local_enr.udp4_socket();
+    let enr_v6_socket = local_enr.udp6_socket();
+    let eth2_field = local_enr
         .eth2()
         .map(|fork_id| hex::encode(fork_id.fork_digest))
         .unwrap_or_default();
 
-    info!(log, "Configuration parameters"; "listening_address" => format!("{}:{}", config.listen_socket.ip(), config.listen_socket.port()), "broadcast_address" => format!("{}:{}",enr_socket.ip(), enr_socket.port()), "eth2" => eth2_field);
+    let pretty_v4_socket = enr_v4_socket.as_ref().map(|addr| addr.to_string());
+    let pretty_v6_socket = enr_v6_socket.as_ref().map(|addr| addr.to_string());
+    info!(
+        log, "Configuration parameters";
+        "listening_address" => %listen_socket,
+        "advertised_v4_address" => ?pretty_v4_socket,
+        "advertised_v6_address" => ?pretty_v6_socket,
+        "eth2" => eth2_field
+    );
 
-    info!(log, "Identity established"; "peer_id" => config.local_enr.peer_id().to_string(), "node_id" => config.local_enr.node_id().to_string());
+    info!(log, "Identity established"; "peer_id" => %local_enr.peer_id(), "node_id" => %local_enr.node_id());
 
     // build the contactable multiaddr list, adding the p2p protocol
-    info!(log, "Contact information"; "enr" => config.local_enr.to_base64());
-    info!(log, "Contact information"; "multiaddrs" => format!("{:?}", config.local_enr.multiaddr_p2p()));
+    info!(log, "Contact information"; "enr" => local_enr.to_base64());
+    info!(log, "Contact information"; "multiaddrs" => ?local_enr.multiaddr_p2p());
 
     // construct the discv5 server
-    let mut discv5 = Discv5::new(
-        config.local_enr.clone(),
-        config.local_key,
-        config.discv5_config,
-    )
-    .unwrap();
+    let mut discv5 = Discv5::new(local_enr.clone(), local_key, discv5_config).unwrap();
 
     // If there are any bootnodes add them to the routing table
-    for enr in config.boot_nodes {
+    for enr in boot_nodes {
         info!(
             log,
             "Adding bootnode";
-            "address" => ?enr.udp4_socket(),
-            "peer_id" => enr.peer_id().to_string(),
-            "node_id" => enr.node_id().to_string()
+            "ipv4_address" => ?enr.udp4_socket(),
+            "ipv6_address" => ?enr.udp6_socket(),
+            "peer_id" => ?enr.peer_id(),
+            "node_id" => ?enr.node_id()
         );
-        if enr != config.local_enr {
+        if enr != local_enr {
             if let Err(e) = discv5.add_enr(enr) {
-                slog::warn!(log, "Failed adding ENR"; "error" => e.to_string());
+                slog::warn!(log, "Failed adding ENR"; "error" => ?e);
             }
         }
     }
 
     // start the server
-    if let Err(e) = discv5.start(config.listen_socket).await {
-        slog::crit!(log, "Could not start discv5 server"; "error" => e.to_string());
+    if let Err(e) = discv5.start(listen_socket).await {
+        slog::crit!(log, "Could not start discv5 server"; "error" => %e);
         return;
     }
 
@@ -72,7 +82,7 @@ pub async fn run<T: EthSpec>(config: BootNodeConfig<T>, log: slog::Logger) {
     let mut event_stream = match discv5.event_stream().await {
         Ok(stream) => stream,
         Err(e) => {
-            slog::crit!(log, "Failed to obtain event stream"; "error" => e.to_string());
+            slog::crit!(log, "Failed to obtain event stream"; "error" => %e);
             return;
         }
     };
@@ -81,9 +91,35 @@ pub async fn run<T: EthSpec>(config: BootNodeConfig<T>, log: slog::Logger) {
     loop {
         tokio::select! {
             _ = metric_interval.tick() => {
+                // Get some ipv4/ipv6 stats to add in the metrics.
+                let mut ipv4_only_reachable: usize = 0;
+                let mut ipv6_only_reachable: usize= 0;
+                let mut ipv4_ipv6_reachable: usize = 0;
+                let mut unreachable_nodes: usize = 0;
+                for enr in discv5.kbuckets().iter_ref().filter_map(|entry| entry.status.is_connected().then_some(entry.node.value)) {
+                    let declares_ipv4 = enr.udp4_socket().is_some();
+                    let declares_ipv6 = enr.udp6_socket().is_some();
+                    match (declares_ipv4, declares_ipv6) {
+                        (true, true) => ipv4_ipv6_reachable += 1,
+                        (true, false) => ipv4_only_reachable += 1,
+                        (false, true) => ipv6_only_reachable += 1,
+                        (false, false) => unreachable_nodes += 1,
+                    }
+                }
+
                 // display server metrics
                 let metrics = discv5.metrics();
-                info!(log, "Server metrics"; "connected_peers" => discv5.connected_peers(), "active_sessions" => metrics.active_sessions, "requests/s" => format!("{:.2}", metrics.unsolicited_requests_per_second));
+                info!(
+                    log, "Server metrics";
+                    "connected_peers" => discv5.connected_peers(),
+                    "active_sessions" => metrics.active_sessions,
+                    "requests/s" => format_args!("{:.2}", metrics.unsolicited_requests_per_second),
+                    "ipv4_nodes" => ipv4_only_reachable,
+                    "ipv6_nodes" => ipv6_only_reachable,
+                    "ipv6_and_ipv4_nodes" => ipv4_ipv6_reachable,
+                    "unreachable_nodes" => unreachable_nodes,
+                );
+
             }
             Some(event) = event_stream.recv() => {
                 match event {
@@ -95,7 +131,7 @@ pub async fn run<T: EthSpec>(config: BootNodeConfig<T>, log: slog::Logger) {
                     Discv5Event::TalkRequest(_) => {}     // Ignore
                     Discv5Event::NodeInserted { .. } => {} // Ignore
                     Discv5Event::SocketUpdated(socket_addr) => {
-                        info!(log, "External socket address updated"; "socket_addr" => format!("{:?}", socket_addr));
+                        info!(log, "Advertised socket address updated"; "socket_addr" => %socket_addr);
                     }
                     Discv5Event::SessionEstablished{ .. } => {} // Ignore
                 }
diff --git a/bors.toml b/bors.toml
index 6edf55bfa..dbe92c68f 100644
--- a/bors.toml
+++ b/bors.toml
@@ -23,7 +23,8 @@ status = [
     "check-msrv",
     "slasher-tests",
     "syncing-simulator-ubuntu",
-    "disallowed-from-async-lint"
+    "disallowed-from-async-lint",
+    "compile-with-beta-compiler"
 ]
 use_squash_merge = true
 timeout_sec = 10800
diff --git a/common/eth2/src/lib.rs b/common/eth2/src/lib.rs
index a89f64162..fcfff7284 100644
--- a/common/eth2/src/lib.rs
+++ b/common/eth2/src/lib.rs
@@ -518,6 +518,29 @@ impl BeaconNodeHttpClient {
         self.get(path).await
     }
 
+    /// `GET beacon/states/{state_id}/randao?epoch`
+    pub async fn get_beacon_states_randao(
+        &self,
+        state_id: StateId,
+        epoch: Option<Epoch>,
+    ) -> Result<Option<ExecutionOptimisticResponse<RandaoMix>>, Error> {
+        let mut path = self.eth_path(V1)?;
+
+        path.path_segments_mut()
+            .map_err(|()| Error::InvalidUrl(self.server.clone()))?
+            .push("beacon")
+            .push("states")
+            .push(&state_id.to_string())
+            .push("randao");
+
+        if let Some(epoch) = epoch {
+            path.query_pairs_mut()
+                .append_pair("epoch", &epoch.to_string());
+        }
+
+        self.get_opt(path).await
+    }
+
     /// `GET beacon/states/{state_id}/validators/{validator_id}`
     ///
     /// Returns `Ok(None)` on a 404 error.
@@ -657,6 +680,17 @@ impl BeaconNodeHttpClient {
         Ok(path)
     }
 
+    /// Path for `v1/beacon/blinded_blocks/{block_id}`
+    pub fn get_beacon_blinded_blocks_path(&self, block_id: BlockId) -> Result<Url, Error> {
+        let mut path = self.eth_path(V1)?;
+        path.path_segments_mut()
+            .map_err(|()| Error::InvalidUrl(self.server.clone()))?
+            .push("beacon")
+            .push("blinded_blocks")
+            .push(&block_id.to_string());
+        Ok(path)
+    }
+
     /// `GET v2/beacon/blocks`
     ///
     /// Returns `Ok(None)` on a 404 error.
@@ -701,6 +735,51 @@ impl BeaconNodeHttpClient {
         }))
     }
 
+    /// `GET v1/beacon/blinded_blocks/{block_id}`
+    ///
+    /// Returns `Ok(None)` on a 404 error.
+    pub async fn get_beacon_blinded_blocks<T: EthSpec>(
+        &self,
+        block_id: BlockId,
+    ) -> Result<Option<ExecutionOptimisticForkVersionedResponse<SignedBlindedBeaconBlock<T>>>, Error>
+    {
+        let path = self.get_beacon_blinded_blocks_path(block_id)?;
+        let response = match self.get_response(path, |b| b).await.optional()? {
+            Some(res) => res,
+            None => return Ok(None),
+        };
+
+        // If present, use the fork provided in the headers to decode the block. Gracefully handle
+        // missing and malformed fork names by falling back to regular deserialisation.
+        let (block, version, execution_optimistic) = match response.fork_name_from_header() {
+            Ok(Some(fork_name)) => {
+                let (data, (version, execution_optimistic)) =
+                    map_fork_name_with!(fork_name, SignedBlindedBeaconBlock, {
+                        let ExecutionOptimisticForkVersionedResponse {
+                            version,
+                            execution_optimistic,
+                            data,
+                        } = response.json().await?;
+                        (data, (version, execution_optimistic))
+                    });
+                (data, version, execution_optimistic)
+            }
+            Ok(None) | Err(_) => {
+                let ExecutionOptimisticForkVersionedResponse {
+                    version,
+                    execution_optimistic,
+                    data,
+                } = response.json().await?;
+                (data, version, execution_optimistic)
+            }
+        };
+        Ok(Some(ExecutionOptimisticForkVersionedResponse {
+            version,
+            execution_optimistic,
+            data: block,
+        }))
+    }
+
     /// `GET v1/beacon/blocks` (LEGACY)
     ///
     /// Returns `Ok(None)` on a 404 error.
@@ -735,6 +814,24 @@ impl BeaconNodeHttpClient {
             .transpose()
     }
 
+    /// `GET beacon/blinded_blocks/{block_id}` as SSZ
+    ///
+    /// Returns `Ok(None)` on a 404 error.
+    pub async fn get_beacon_blinded_blocks_ssz<T: EthSpec>(
+        &self,
+        block_id: BlockId,
+        spec: &ChainSpec,
+    ) -> Result<Option<SignedBlindedBeaconBlock<T>>, Error> {
+        let path = self.get_beacon_blinded_blocks_path(block_id)?;
+
+        self.get_bytes_opt_accept_header(path, Accept::Ssz, self.timeouts.get_beacon_blocks_ssz)
+            .await?
+            .map(|bytes| {
+                SignedBlindedBeaconBlock::from_ssz_bytes(&bytes, spec).map_err(Error::InvalidSsz)
+            })
+            .transpose()
+    }
+
     /// `GET beacon/blocks/{block_id}/root`
     ///
     /// Returns `Ok(None)` on a 404 error.
diff --git a/common/eth2/src/types.rs b/common/eth2/src/types.rs
index 71e5b40e0..4b7ae5539 100644
--- a/common/eth2/src/types.rs
+++ b/common/eth2/src/types.rs
@@ -455,6 +455,11 @@ pub struct SyncCommitteesQuery {
     pub epoch: Option<Epoch>,
 }
 
+#[derive(Serialize, Deserialize)]
+pub struct RandaoQuery {
+    pub epoch: Option<Epoch>,
+}
+
 #[derive(Serialize, Deserialize)]
 pub struct AttestationPoolQuery {
     pub slot: Option<Slot>,
@@ -486,6 +491,11 @@ pub struct SyncCommitteeByValidatorIndices {
     pub validator_aggregates: Vec<SyncSubcommittee>,
 }
 
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
+pub struct RandaoMix {
+    pub randao: Hash256,
+}
+
 #[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
 #[serde(transparent)]
 pub struct SyncSubcommittee {
diff --git a/common/eth2_network_config/built_in_network_configs/gnosis/config.yaml b/common/eth2_network_config/built_in_network_configs/gnosis/config.yaml
index 7987899c3..d55ef3f3b 100644
--- a/common/eth2_network_config/built_in_network_configs/gnosis/config.yaml
+++ b/common/eth2_network_config/built_in_network_configs/gnosis/config.yaml
@@ -6,8 +6,8 @@ PRESET_BASE: 'gnosis'
 
 # Transition
 # ---------------------------------------------------------------
-# TBD, 2**256-2**10 is a placeholder
-TERMINAL_TOTAL_DIFFICULTY: 115792089237316195423570985008687907853269984665640564039457584007913129638912
+# Estimated on Dec 5, 2022
+TERMINAL_TOTAL_DIFFICULTY: 8626000000000000000000058750000000000000000000
 # By default, don't use these params
 TERMINAL_BLOCK_HASH: 0x0000000000000000000000000000000000000000000000000000000000000000
 TERMINAL_BLOCK_HASH_ACTIVATION_EPOCH: 18446744073709551615
@@ -35,7 +35,7 @@ ALTAIR_FORK_VERSION: 0x01000064
 ALTAIR_FORK_EPOCH: 512
 # Merge
 BELLATRIX_FORK_VERSION: 0x02000064
-BELLATRIX_FORK_EPOCH: 18446744073709551615
+BELLATRIX_FORK_EPOCH: 385536
 # Sharding
 SHARDING_FORK_VERSION: 0x03000064
 SHARDING_FORK_EPOCH: 18446744073709551615
diff --git a/common/eth2_network_config/src/lib.rs b/common/eth2_network_config/src/lib.rs
index 2bfd00326..7aef78437 100644
--- a/common/eth2_network_config/src/lib.rs
+++ b/common/eth2_network_config/src/lib.rs
@@ -226,7 +226,7 @@ mod tests {
     use super::*;
     use ssz::Encode;
     use tempfile::Builder as TempBuilder;
-    use types::{Config, Eth1Data, GnosisEthSpec, Hash256, MainnetEthSpec, GNOSIS};
+    use types::{Config, Eth1Data, GnosisEthSpec, Hash256, MainnetEthSpec};
 
     type E = MainnetEthSpec;
 
@@ -250,6 +250,13 @@ mod tests {
         assert_eq!(spec, config.chain_spec::<E>().unwrap());
     }
 
+    #[test]
+    fn gnosis_config_eq_chain_spec() {
+        let config = Eth2NetworkConfig::from_hardcoded_net(&GNOSIS).unwrap();
+        let spec = ChainSpec::gnosis();
+        assert_eq!(spec, config.chain_spec::<GnosisEthSpec>().unwrap());
+    }
+
     #[test]
     fn mainnet_genesis_state() {
         let config = Eth2NetworkConfig::from_hardcoded_net(&MAINNET).unwrap();
@@ -270,7 +277,7 @@ mod tests {
                 .unwrap_or_else(|_| panic!("{:?}", net.name));
 
             // Ensure we can parse the YAML config to a chain spec.
-            if net.name == GNOSIS {
+            if net.name == types::GNOSIS {
                 config.chain_spec::<GnosisEthSpec>().unwrap();
             } else {
                 config.chain_spec::<MainnetEthSpec>().unwrap();
diff --git a/common/lighthouse_version/src/lib.rs b/common/lighthouse_version/src/lib.rs
index a48ba211d..afcbae513 100644
--- a/common/lighthouse_version/src/lib.rs
+++ b/common/lighthouse_version/src/lib.rs
@@ -17,8 +17,8 @@ pub const VERSION: &str = git_version!(
         // NOTE: using --match instead of --exclude for compatibility with old Git
         "--match=thiswillnevermatchlol"
     ],
-    prefix = "Lighthouse/v3.2.1-",
-    fallback = "Lighthouse/v3.2.1"
+    prefix = "Lighthouse/v3.3.0-",
+    fallback = "Lighthouse/v3.3.0"
 );
 
 /// Returns `VERSION`, but with platform information appended to the end.
diff --git a/common/system_health/Cargo.toml b/common/system_health/Cargo.toml
new file mode 100644
index 000000000..0956710b8
--- /dev/null
+++ b/common/system_health/Cargo.toml
@@ -0,0 +1,13 @@
+[package]
+name = "system_health"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+lighthouse_network = { path = "../../beacon_node/lighthouse_network" }
+types = { path = "../../consensus/types" }
+sysinfo = "0.26.5"
+serde = "1.0.116"
+serde_derive = "1.0.116"
+serde_json = "1.0.58"
+parking_lot = "0.12.0"
diff --git a/common/system_health/src/lib.rs b/common/system_health/src/lib.rs
new file mode 100644
index 000000000..d10540e50
--- /dev/null
+++ b/common/system_health/src/lib.rs
@@ -0,0 +1,241 @@
+use lighthouse_network::{types::SyncState, NetworkGlobals};
+use parking_lot::RwLock;
+use serde::{Deserialize, Serialize};
+use std::path::{Path, PathBuf};
+use std::sync::Arc;
+use sysinfo::{CpuExt, DiskExt, NetworkExt, NetworksExt, System, SystemExt};
+use types::EthSpec;
+
+#[derive(Clone, Debug, PartialEq, Serialize, Deserialize)]
+pub struct SystemHealth {
+    /// Total memory of the system.
+    pub total_memory: u64,
+    /// Total free memory available to the system.
+    pub free_memory: u64,
+    /// Total used memory.
+    pub used_memory: u64,
+
+    /// System load average over 1 minute.
+    pub sys_loadavg_1: f64,
+    /// System load average over 5 minutes.
+    pub sys_loadavg_5: f64,
+    /// System load average over 15 minutes.
+    pub sys_loadavg_15: f64,
+
+    /// Total cpu cores.
+    pub cpu_cores: usize,
+    /// Total cpu threads.
+    pub cpu_threads: usize,
+    /// The global cpu frequency.
+    pub global_cpu_frequency: f32,
+
+    /// Total capacity of disk.
+    pub disk_bytes_total: u64,
+    /// Free space in disk.
+    pub disk_bytes_free: u64,
+
+    /// System uptime.
+    pub system_uptime: u64,
+    /// Application uptime.
+    pub app_uptime: u64,
+    /// The System name
+    pub system_name: String,
+    /// Kernel version
+    pub kernel_version: String,
+    /// OS version
+    pub os_version: String,
+    /// Hostname
+    pub host_name: String,
+}
+
+/// System related health, specific to the UI for the validator client.
+#[derive(Clone, Debug, PartialEq, Serialize, Deserialize)]
+pub struct SystemHealthVC {
+    #[serde(flatten)]
+    pub system_health: SystemHealth,
+}
+
+/// System related health, specific to the UI for the Beacon Node.
+#[derive(Clone, Debug, PartialEq, Serialize, Deserialize)]
+pub struct SystemHealthBN {
+    #[serde(flatten)]
+    pub system_health: SystemHealth,
+    /// The name of the network that uses the most traffic.
+    pub network_name: String,
+    /// Total bytes received over the main interface.
+    pub network_bytes_total_received: u64,
+    /// Total bytes sent over the main interface.
+    pub network_bytes_total_transmit: u64,
+
+    /// The current NAT status.
+    pub nat_open: bool,
+    /// The current number of connected peers.
+    pub connected_peers: usize,
+    /// The current syncing state of the consensus node.
+    pub sync_state: SyncState,
+}
+
+/// Populates the system health.
+fn observe_system_health(
+    sysinfo: Arc<RwLock<System>>,
+    data_dir: PathBuf,
+    app_uptime: u64,
+) -> SystemHealth {
+    let sysinfo = sysinfo.read();
+    let loadavg = sysinfo.load_average();
+
+    let cpus = sysinfo.cpus();
+
+    let disks = sysinfo.disks();
+
+    let system_uptime = sysinfo.uptime();
+
+    // Helper functions to extract specific data
+
+    // Find fs associated with the data dir location and report this
+    let (disk_bytes_total, disk_bytes_free) = {
+        // There is no clean way to find this in an OS-agnostic way. We take a simple approach,
+        // which is attempt to match the mount_point to the data_dir. If this cannot be done, we
+        // just fallback to the root fs.
+
+        let mut root_fs_disk = None;
+        let mut other_matching_fs = None;
+
+        for disk in disks.iter() {
+            if disk.mount_point() == Path::new("/")
+                || disk.mount_point() == Path::new("C:\\")
+                || disk.mount_point() == Path::new("/System/Volumes/Data")
+            {
+                // Found the usual default root_fs
+                root_fs_disk = Some(disk);
+                continue;
+            }
+
+            // If we have other file systems, compare these to the data_dir of Lighthouse and
+            // prioritize these.
+            if data_dir
+                .to_str()
+                .map(|path| {
+                    if let Some(mount_str) = disk.mount_point().to_str() {
+                        path.contains(mount_str)
+                    } else {
+                        false
+                    }
+                })
+                .unwrap_or(false)
+            {
+                other_matching_fs = Some(disk);
+                break; // Don't bother finding other competing fs.
+            }
+        }
+
+        // If we found a file system other than the root, report this, otherwise just report the
+        // root fs
+        let fs = other_matching_fs.or(root_fs_disk);
+
+        // If the root fs is not known, just add up the total of all known partitions
+        match fs {
+            Some(fs) => (fs.total_space(), fs.available_space()),
+            None => {
+                // If we can't find a known partition, just add them all up
+                disks.iter().fold((0, 0), |mut current_sizes, disk| {
+                    current_sizes.0 += disk.total_space();
+                    current_sizes.1 += disk.available_space();
+                    current_sizes
+                })
+            }
+        }
+    };
+
+    // Attempt to get the clock speed from the name of the CPU
+    let cpu_frequency_from_name = cpus.iter().next().and_then(|cpu| {
+        cpu.brand()
+            .split_once("GHz")
+            .and_then(|(result, _)| result.trim().rsplit_once(' '))
+            .and_then(|(_, result)| result.parse::<f32>().ok())
+    });
+
+    let global_cpu_frequency = match cpu_frequency_from_name {
+        Some(freq) => freq,
+        None => {
+            // Get the frequency from average measured frequencies
+            let global_cpu_frequency: f32 =
+                cpus.iter().map(|cpu| cpu.frequency()).sum::<u64>() as f32 / cpus.len() as f32;
+            // Shift to ghz to 1dp
+            (global_cpu_frequency / 100.0).round() / 10.0
+        }
+    };
+
+    SystemHealth {
+        total_memory: sysinfo.total_memory(),
+        free_memory: sysinfo.free_memory(),
+        used_memory: sysinfo.used_memory(),
+        sys_loadavg_1: loadavg.one,
+        sys_loadavg_5: loadavg.five,
+        sys_loadavg_15: loadavg.fifteen,
+        cpu_cores: sysinfo.physical_core_count().unwrap_or(0),
+        cpu_threads: cpus.len(),
+        global_cpu_frequency,
+        disk_bytes_total,
+        disk_bytes_free,
+        system_uptime,
+        app_uptime,
+        system_name: sysinfo.name().unwrap_or_else(|| String::from("")),
+        kernel_version: sysinfo.kernel_version().unwrap_or_else(|| "".into()),
+        os_version: sysinfo.long_os_version().unwrap_or_else(|| "".into()),
+        host_name: sysinfo.host_name().unwrap_or_else(|| "".into()),
+    }
+}
+
+/// Observes the Validator client system health.
+pub fn observe_system_health_vc(
+    sysinfo: Arc<RwLock<System>>,
+    data_dir: PathBuf,
+    app_uptime: u64,
+) -> SystemHealthVC {
+    SystemHealthVC {
+        system_health: observe_system_health(sysinfo, data_dir, app_uptime),
+    }
+}
+
+/// Observes the Beacon Node system health.
+pub fn observe_system_health_bn<TSpec: EthSpec>(
+    sysinfo: Arc<RwLock<System>>,
+    data_dir: PathBuf,
+    app_uptime: u64,
+    network_globals: Arc<NetworkGlobals<TSpec>>,
+) -> SystemHealthBN {
+    let system_health = observe_system_health(sysinfo.clone(), data_dir, app_uptime);
+
+    // Find the network with the most traffic and assume this is the main network
+    let sysinfo = sysinfo.read();
+    let networks = sysinfo.networks();
+    let (network_name, network_bytes_total_received, network_bytes_total_transmit) = networks
+        .iter()
+        .max_by_key(|(_name, network)| network.total_received())
+        .map(|(name, network)| {
+            (
+                name.clone(),
+                network.total_received(),
+                network.total_transmitted(),
+            )
+        })
+        .unwrap_or_else(|| (String::from("None"), 0, 0));
+
+    // Determine if the NAT is open or not.
+    let nat_open = lighthouse_network::metrics::NAT_OPEN
+        .as_ref()
+        .map(|v| v.get())
+        .unwrap_or(0)
+        != 0;
+
+    SystemHealthBN {
+        system_health,
+        network_name,
+        network_bytes_total_received,
+        network_bytes_total_transmit,
+        nat_open,
+        connected_peers: network_globals.connected_peers(),
+        sync_state: network_globals.sync_state(),
+    }
+}
diff --git a/consensus/ssz_types/src/bitfield.rs b/consensus/ssz_types/src/bitfield.rs
index b0cf4551e..0539cc7d2 100644
--- a/consensus/ssz_types/src/bitfield.rs
+++ b/consensus/ssz_types/src/bitfield.rs
@@ -22,7 +22,7 @@ pub trait BitfieldBehaviour: Clone {}
 /// A marker struct used to declare SSZ `Variable` behaviour on a `Bitfield`.
 ///
 /// See the [`Bitfield`](struct.Bitfield.html) docs for usage.
-#[derive(Clone, PartialEq, Debug)]
+#[derive(Clone, PartialEq, Eq, Debug)]
 pub struct Variable<N> {
     _phantom: PhantomData<N>,
 }
@@ -30,7 +30,7 @@ pub struct Variable<N> {
 /// A marker struct used to declare SSZ `Fixed` behaviour on a `Bitfield`.
 ///
 /// See the [`Bitfield`](struct.Bitfield.html) docs for usage.
-#[derive(Clone, PartialEq, Debug)]
+#[derive(Clone, PartialEq, Eq, Debug)]
 pub struct Fixed<N> {
     _phantom: PhantomData<N>,
 }
@@ -96,7 +96,7 @@ pub type BitVector<N> = Bitfield<Fixed<N>>;
 /// byte (by `Vec` index) stores the lowest bit-indices and the right-most bit stores the lowest
 /// bit-index. E.g., `smallvec![0b0000_0001, 0b0000_0010]` has bits `0, 9` set.
 #[derive(Clone, Debug, Derivative)]
-#[derivative(PartialEq, Hash(bound = ""))]
+#[derivative(PartialEq, Eq, Hash(bound = ""))]
 pub struct Bitfield<T> {
     bytes: SmallVec<[u8; SMALLVEC_LEN]>,
     len: usize,
diff --git a/consensus/state_processing/src/consensus_context.rs b/consensus/state_processing/src/consensus_context.rs
index f66e578fe..d9453d364 100644
--- a/consensus/state_processing/src/consensus_context.rs
+++ b/consensus/state_processing/src/consensus_context.rs
@@ -1,9 +1,13 @@
+use crate::common::get_indexed_attestation;
+use crate::per_block_processing::errors::{AttestationInvalid, BlockOperationError};
+use std::collections::{hash_map::Entry, HashMap};
 use std::marker::PhantomData;
 use std::sync::Arc;
 use tree_hash::TreeHash;
 use types::{
-    AbstractExecPayload, BeaconState, BeaconStateError, BlobsSidecar, ChainSpec, EthSpec,
-    ExecPayload, Hash256, SignedBeaconBlock, Slot,
+    AbstractExecPayload, Attestation, AttestationData, BeaconState, BeaconStateError, BitList,
+    BlobsSidecar, ChainSpec, Epoch, EthSpec, ExecPayload, Hash256, IndexedAttestation,
+    SignedBeaconBlock, Slot,
 };
 
 #[derive(Debug)]
@@ -14,6 +18,9 @@ pub struct ConsensusContext<T: EthSpec> {
     proposer_index: Option<u64>,
     /// Block root of the block at `slot`.
     current_block_root: Option<Hash256>,
+    /// Cache of indexed attestations constructed during block processing.
+    indexed_attestations:
+        HashMap<(AttestationData, BitList<T::MaxValidatorsPerCommittee>), IndexedAttestation<T>>,
     /// Should only be populated if the sidecar has not been validated.
     blobs_sidecar: Option<Arc<BlobsSidecar<T>>>,
     /// Whether `validate_blobs_sidecar` has successfully passed.
@@ -26,6 +33,7 @@ pub struct ConsensusContext<T: EthSpec> {
 pub enum ContextError {
     BeaconState(BeaconStateError),
     SlotMismatch { slot: Slot, expected: Slot },
+    EpochMismatch { epoch: Epoch, expected: Epoch },
 }
 
 impl From<BeaconStateError> for ContextError {
@@ -40,6 +48,7 @@ impl<T: EthSpec> ConsensusContext<T> {
             slot,
             proposer_index: None,
             current_block_root: None,
+            indexed_attestations: HashMap::new(),
             blobs_sidecar: None,
             blobs_sidecar_validated: false,
             blobs_verified_vs_txs: false,
@@ -51,13 +60,39 @@ impl<T: EthSpec> ConsensusContext<T> {
         self
     }
 
+    /// Strict method for fetching the proposer index.
+    ///
+    /// Gets the proposer index for `self.slot` while ensuring that it matches `state.slot()`. This
+    /// method should be used in block processing and almost everywhere the proposer index is
+    /// required. If the slot check is too restrictive, see `get_proposer_index_from_epoch_state`.
     pub fn get_proposer_index(
         &mut self,
         state: &BeaconState<T>,
         spec: &ChainSpec,
     ) -> Result<u64, ContextError> {
         self.check_slot(state.slot())?;
+        self.get_proposer_index_no_checks(state, spec)
+    }
 
+    /// More liberal method for fetching the proposer index.
+    ///
+    /// Fetches the proposer index for `self.slot` but does not require the state to be from an
+    /// exactly matching slot (merely a matching epoch). This is useful in batch verification where
+    /// we want to extract the proposer index from a single state for every slot in the epoch.
+    pub fn get_proposer_index_from_epoch_state(
+        &mut self,
+        state: &BeaconState<T>,
+        spec: &ChainSpec,
+    ) -> Result<u64, ContextError> {
+        self.check_epoch(state.current_epoch())?;
+        self.get_proposer_index_no_checks(state, spec)
+    }
+
+    fn get_proposer_index_no_checks(
+        &mut self,
+        state: &BeaconState<T>,
+        spec: &ChainSpec,
+    ) -> Result<u64, ContextError> {
         if let Some(proposer_index) = self.proposer_index {
             return Ok(proposer_index);
         }
@@ -98,6 +133,41 @@ impl<T: EthSpec> ConsensusContext<T> {
         }
     }
 
+    fn check_epoch(&self, epoch: Epoch) -> Result<(), ContextError> {
+        let expected = self.slot.epoch(T::slots_per_epoch());
+        if epoch == expected {
+            Ok(())
+        } else {
+            Err(ContextError::EpochMismatch { epoch, expected })
+        }
+    }
+
+    pub fn get_indexed_attestation(
+        &mut self,
+        state: &BeaconState<T>,
+        attestation: &Attestation<T>,
+    ) -> Result<&IndexedAttestation<T>, BlockOperationError<AttestationInvalid>> {
+        let key = (
+            attestation.data.clone(),
+            attestation.aggregation_bits.clone(),
+        );
+
+        match self.indexed_attestations.entry(key) {
+            Entry::Occupied(occupied) => Ok(occupied.into_mut()),
+            Entry::Vacant(vacant) => {
+                let committee =
+                    state.get_beacon_committee(attestation.data.slot, attestation.data.index)?;
+                let indexed_attestation =
+                    get_indexed_attestation(committee.committee, attestation)?;
+                Ok(vacant.insert(indexed_attestation))
+            }
+        }
+    }
+
+    pub fn num_cached_indexed_attestations(&self) -> usize {
+        self.indexed_attestations.len()
+    }
+
     pub fn set_blobs_sidecar_validated(mut self, blobs_sidecar_validated: bool) -> Self {
         self.blobs_sidecar_validated = blobs_sidecar_validated;
         self
diff --git a/consensus/state_processing/src/per_block_processing.rs b/consensus/state_processing/src/per_block_processing.rs
index a10452dcc..02843727a 100644
--- a/consensus/state_processing/src/per_block_processing.rs
+++ b/consensus/state_processing/src/per_block_processing.rs
@@ -117,16 +117,13 @@ pub fn per_block_processing<T: EthSpec, Payload: AbstractExecPayload<T>>(
     let verify_signatures = match block_signature_strategy {
         BlockSignatureStrategy::VerifyBulk => {
             // Verify all signatures in the block at once.
-            let block_root = Some(ctxt.get_current_block_root(signed_block)?);
-            let proposer_index = Some(ctxt.get_proposer_index(state, spec)?);
             block_verify!(
                 BlockSignatureVerifier::verify_entire_block(
                     state,
                     |i| get_pubkey_from_state(state, i),
                     |pk_bytes| pk_bytes.decompress().ok().map(Cow::Owned),
                     signed_block,
-                    block_root,
-                    proposer_index,
+                    ctxt,
                     spec
                 )
                 .is_ok(),
@@ -352,6 +349,7 @@ pub fn get_new_eth1_data<T: EthSpec>(
 /// https://github.com/ethereum/consensus-specs/blob/v1.1.5/specs/merge/beacon-chain.md#process_execution_payload
 pub fn partially_verify_execution_payload<'payload, T: EthSpec, Payload: AbstractExecPayload<T>>(
     state: &BeaconState<T>,
+    block_slot: Slot,
     payload: Payload::Ref<'payload>,
     spec: &ChainSpec,
 ) -> Result<(), BlockProcessingError> {
@@ -372,7 +370,7 @@ pub fn partially_verify_execution_payload<'payload, T: EthSpec, Payload: Abstrac
         }
     );
 
-    let timestamp = compute_timestamp_at_slot(state, spec)?;
+    let timestamp = compute_timestamp_at_slot(state, block_slot, spec)?;
     block_verify!(
         payload.timestamp() == timestamp,
         BlockProcessingError::ExecutionInvalidTimestamp {
@@ -396,7 +394,7 @@ pub fn process_execution_payload<'payload, T: EthSpec, Payload: AbstractExecPayl
     payload: Payload::Ref<'payload>,
     spec: &ChainSpec,
 ) -> Result<(), BlockProcessingError> {
-    partially_verify_execution_payload::<T, Payload>(state, payload, spec)?;
+    partially_verify_execution_payload::<T, Payload>(state, state.slot(), payload, spec)?;
 
     match state.latest_execution_payload_header_mut()? {
         ExecutionPayloadHeaderRefMut::Merge(header_mut) => {
@@ -459,9 +457,10 @@ pub fn is_execution_enabled<T: EthSpec, Payload: AbstractExecPayload<T>>(
 /// https://github.com/ethereum/consensus-specs/blob/dev/specs/bellatrix/beacon-chain.md#compute_timestamp_at_slot
 pub fn compute_timestamp_at_slot<T: EthSpec>(
     state: &BeaconState<T>,
+    block_slot: Slot,
     spec: &ChainSpec,
 ) -> Result<u64, ArithError> {
-    let slots_since_genesis = state.slot().as_u64().safe_sub(spec.genesis_slot.as_u64())?;
+    let slots_since_genesis = block_slot.as_u64().safe_sub(spec.genesis_slot.as_u64())?;
     slots_since_genesis
         .safe_mul(spec.seconds_per_slot)
         .and_then(|since_genesis| state.genesis_time().safe_add(since_genesis))
diff --git a/consensus/state_processing/src/per_block_processing/block_signature_verifier.rs b/consensus/state_processing/src/per_block_processing/block_signature_verifier.rs
index a8d0acc55..fe654fcaa 100644
--- a/consensus/state_processing/src/per_block_processing/block_signature_verifier.rs
+++ b/consensus/state_processing/src/per_block_processing/block_signature_verifier.rs
@@ -1,8 +1,8 @@
 #![allow(clippy::integer_arithmetic)]
 
 use super::signature_sets::{Error as SignatureSetError, *};
-use crate::common::get_indexed_attestation;
 use crate::per_block_processing::errors::{AttestationInvalid, BlockOperationError};
+use crate::{ConsensusContext, ContextError};
 use bls::{verify_signature_sets, PublicKey, PublicKeyBytes, SignatureSet};
 use rayon::prelude::*;
 use std::borrow::Cow;
@@ -28,6 +28,8 @@ pub enum Error {
     IncorrectBlockProposer { block: u64, local_shuffling: u64 },
     /// Failed to load a signature set. The block may be invalid or we failed to process it.
     SignatureSetError(SignatureSetError),
+    /// Error related to the consensus context, likely the proposer index or block root calc.
+    ContextError(ContextError),
 }
 
 impl From<BeaconStateError> for Error {
@@ -36,6 +38,12 @@ impl From<BeaconStateError> for Error {
     }
 }
 
+impl From<ContextError> for Error {
+    fn from(e: ContextError) -> Error {
+        Error::ContextError(e)
+    }
+}
+
 impl From<SignatureSetError> for Error {
     fn from(e: SignatureSetError) -> Error {
         match e {
@@ -122,12 +130,11 @@ where
         get_pubkey: F,
         decompressor: D,
         block: &'a SignedBeaconBlock<T, Payload>,
-        block_root: Option<Hash256>,
-        verified_proposer_index: Option<u64>,
+        ctxt: &mut ConsensusContext<T>,
         spec: &'a ChainSpec,
     ) -> Result<()> {
         let mut verifier = Self::new(state, get_pubkey, decompressor, spec);
-        verifier.include_all_signatures(block, block_root, verified_proposer_index)?;
+        verifier.include_all_signatures(block, ctxt)?;
         verifier.verify()
     }
 
@@ -135,11 +142,14 @@ where
     pub fn include_all_signatures<Payload: AbstractExecPayload<T>>(
         &mut self,
         block: &'a SignedBeaconBlock<T, Payload>,
-        block_root: Option<Hash256>,
-        verified_proposer_index: Option<u64>,
+        ctxt: &mut ConsensusContext<T>,
     ) -> Result<()> {
+        let block_root = Some(ctxt.get_current_block_root(block)?);
+        let verified_proposer_index =
+            Some(ctxt.get_proposer_index_from_epoch_state(self.state, self.spec)?);
+
         self.include_block_proposal(block, block_root, verified_proposer_index)?;
-        self.include_all_signatures_except_proposal(block, verified_proposer_index)?;
+        self.include_all_signatures_except_proposal(block, ctxt)?;
 
         Ok(())
     }
@@ -149,12 +159,14 @@ where
     pub fn include_all_signatures_except_proposal<Payload: AbstractExecPayload<T>>(
         &mut self,
         block: &'a SignedBeaconBlock<T, Payload>,
-        verified_proposer_index: Option<u64>,
+        ctxt: &mut ConsensusContext<T>,
     ) -> Result<()> {
+        let verified_proposer_index =
+            Some(ctxt.get_proposer_index_from_epoch_state(self.state, self.spec)?);
         self.include_randao_reveal(block, verified_proposer_index)?;
         self.include_proposer_slashings(block)?;
         self.include_attester_slashings(block)?;
-        self.include_attestations(block)?;
+        self.include_attestations(block, ctxt)?;
         // Deposits are not included because they can legally have invalid signatures.
         self.include_exits(block)?;
         self.include_sync_aggregate(block)?;
@@ -262,7 +274,8 @@ where
     pub fn include_attestations<Payload: AbstractExecPayload<T>>(
         &mut self,
         block: &'a SignedBeaconBlock<T, Payload>,
-    ) -> Result<Vec<IndexedAttestation<T>>> {
+        ctxt: &mut ConsensusContext<T>,
+    ) -> Result<()> {
         self.sets
             .sets
             .reserve(block.message().body().attestations().len());
@@ -272,28 +285,18 @@ where
             .body()
             .attestations()
             .iter()
-            .try_fold(
-                Vec::with_capacity(block.message().body().attestations().len()),
-                |mut vec, attestation| {
-                    let committee = self
-                        .state
-                        .get_beacon_committee(attestation.data.slot, attestation.data.index)?;
-                    let indexed_attestation =
-                        get_indexed_attestation(committee.committee, attestation)?;
+            .try_for_each(|attestation| {
+                let indexed_attestation = ctxt.get_indexed_attestation(self.state, attestation)?;
 
-                    self.sets.push(indexed_attestation_signature_set(
-                        self.state,
-                        self.get_pubkey.clone(),
-                        &attestation.signature,
-                        &indexed_attestation,
-                        self.spec,
-                    )?);
-
-                    vec.push(indexed_attestation);
-
-                    Ok(vec)
-                },
-            )
+                self.sets.push(indexed_attestation_signature_set(
+                    self.state,
+                    self.get_pubkey.clone(),
+                    &attestation.signature,
+                    indexed_attestation,
+                    self.spec,
+                )?);
+                Ok(())
+            })
             .map_err(Error::into)
     }
 
diff --git a/consensus/state_processing/src/per_block_processing/process_operations.rs b/consensus/state_processing/src/per_block_processing/process_operations.rs
index be23255e3..3361034b5 100644
--- a/consensus/state_processing/src/per_block_processing/process_operations.rs
+++ b/consensus/state_processing/src/per_block_processing/process_operations.rs
@@ -63,8 +63,14 @@ pub mod base {
 
         // Verify and apply each attestation.
         for (i, attestation) in attestations.iter().enumerate() {
-            verify_attestation_for_block_inclusion(state, attestation, verify_signatures, spec)
-                .map_err(|e| e.into_with_index(i))?;
+            verify_attestation_for_block_inclusion(
+                state,
+                attestation,
+                ctxt,
+                verify_signatures,
+                spec,
+            )
+            .map_err(|e| e.into_with_index(i))?;
 
             let pending_attestation = PendingAttestation {
                 aggregation_bits: attestation.aggregation_bits.clone(),
@@ -100,19 +106,11 @@ pub mod altair {
         ctxt: &mut ConsensusContext<T>,
         spec: &ChainSpec,
     ) -> Result<(), BlockProcessingError> {
-        let proposer_index = ctxt.get_proposer_index(state, spec)?;
         attestations
             .iter()
             .enumerate()
             .try_for_each(|(i, attestation)| {
-                process_attestation(
-                    state,
-                    attestation,
-                    i,
-                    proposer_index,
-                    verify_signatures,
-                    spec,
-                )
+                process_attestation(state, attestation, i, ctxt, verify_signatures, spec)
             })
     }
 
@@ -120,16 +118,24 @@ pub mod altair {
         state: &mut BeaconState<T>,
         attestation: &Attestation<T>,
         att_index: usize,
-        proposer_index: u64,
+        ctxt: &mut ConsensusContext<T>,
         verify_signatures: VerifySignatures,
         spec: &ChainSpec,
     ) -> Result<(), BlockProcessingError> {
         state.build_committee_cache(RelativeEpoch::Previous, spec)?;
         state.build_committee_cache(RelativeEpoch::Current, spec)?;
 
-        let indexed_attestation =
-            verify_attestation_for_block_inclusion(state, attestation, verify_signatures, spec)
-                .map_err(|e| e.into_with_index(att_index))?;
+        let proposer_index = ctxt.get_proposer_index(state, spec)?;
+
+        let attesting_indices = &verify_attestation_for_block_inclusion(
+            state,
+            attestation,
+            ctxt,
+            verify_signatures,
+            spec,
+        )
+        .map_err(|e| e.into_with_index(att_index))?
+        .attesting_indices;
 
         // Matching roots, participation flag indices
         let data = &attestation.data;
@@ -141,7 +147,7 @@ pub mod altair {
         let total_active_balance = state.get_total_active_balance()?;
         let base_reward_per_increment = BaseRewardPerIncrement::new(total_active_balance, spec)?;
         let mut proposer_reward_numerator = 0;
-        for index in &indexed_attestation.attesting_indices {
+        for index in attesting_indices {
             let index = *index as usize;
 
             for (flag_index, &weight) in PARTICIPATION_FLAG_WEIGHTS.iter().enumerate() {
diff --git a/consensus/state_processing/src/per_block_processing/verify_attestation.rs b/consensus/state_processing/src/per_block_processing/verify_attestation.rs
index 5d8113af4..303a6e391 100644
--- a/consensus/state_processing/src/per_block_processing/verify_attestation.rs
+++ b/consensus/state_processing/src/per_block_processing/verify_attestation.rs
@@ -1,7 +1,7 @@
 use super::errors::{AttestationInvalid as Invalid, BlockOperationError};
 use super::VerifySignatures;
-use crate::common::get_indexed_attestation;
 use crate::per_block_processing::is_valid_indexed_attestation;
+use crate::ConsensusContext;
 use safe_arith::SafeArith;
 use types::*;
 
@@ -15,12 +15,13 @@ fn error(reason: Invalid) -> BlockOperationError<Invalid> {
 /// to `state`. Otherwise, returns a descriptive `Err`.
 ///
 /// Optionally verifies the aggregate signature, depending on `verify_signatures`.
-pub fn verify_attestation_for_block_inclusion<T: EthSpec>(
+pub fn verify_attestation_for_block_inclusion<'ctxt, T: EthSpec>(
     state: &BeaconState<T>,
     attestation: &Attestation<T>,
+    ctxt: &'ctxt mut ConsensusContext<T>,
     verify_signatures: VerifySignatures,
     spec: &ChainSpec,
-) -> Result<IndexedAttestation<T>> {
+) -> Result<&'ctxt IndexedAttestation<T>> {
     let data = &attestation.data;
 
     verify!(
@@ -39,7 +40,7 @@ pub fn verify_attestation_for_block_inclusion<T: EthSpec>(
         }
     );
 
-    verify_attestation_for_state(state, attestation, verify_signatures, spec)
+    verify_attestation_for_state(state, attestation, ctxt, verify_signatures, spec)
 }
 
 /// Returns `Ok(())` if `attestation` is a valid attestation to the chain that precedes the given
@@ -49,12 +50,13 @@ pub fn verify_attestation_for_block_inclusion<T: EthSpec>(
 /// prior blocks in `state`.
 ///
 /// Spec v0.12.1
-pub fn verify_attestation_for_state<T: EthSpec>(
+pub fn verify_attestation_for_state<'ctxt, T: EthSpec>(
     state: &BeaconState<T>,
     attestation: &Attestation<T>,
+    ctxt: &'ctxt mut ConsensusContext<T>,
     verify_signatures: VerifySignatures,
     spec: &ChainSpec,
-) -> Result<IndexedAttestation<T>> {
+) -> Result<&'ctxt IndexedAttestation<T>> {
     let data = &attestation.data;
 
     verify!(
@@ -66,9 +68,8 @@ pub fn verify_attestation_for_state<T: EthSpec>(
     verify_casper_ffg_vote(attestation, state)?;
 
     // Check signature and bitfields
-    let committee = state.get_beacon_committee(attestation.data.slot, attestation.data.index)?;
-    let indexed_attestation = get_indexed_attestation(committee.committee, attestation)?;
-    is_valid_indexed_attestation(state, &indexed_attestation, verify_signatures, spec)?;
+    let indexed_attestation = ctxt.get_indexed_attestation(state, attestation)?;
+    is_valid_indexed_attestation(state, indexed_attestation, verify_signatures, spec)?;
 
     Ok(indexed_attestation)
 }
diff --git a/consensus/types/Cargo.toml b/consensus/types/Cargo.toml
index 49fa49c20..be1c3191f 100644
--- a/consensus/types/Cargo.toml
+++ b/consensus/types/Cargo.toml
@@ -9,6 +9,8 @@ name = "benches"
 harness = false
 
 [dependencies]
+serde-big-array = {version = "0.3.2", features = ["const-generics"]}
+merkle_proof = { path = "../../consensus/merkle_proof" }
 bls = { path = "../../crypto/bls" }
 kzg = { path = "../../crypto/kzg" }
 compare_fields = { path = "../../common/compare_fields" }
diff --git a/consensus/types/src/beacon_state.rs b/consensus/types/src/beacon_state.rs
index 000e6f671..48a83f94f 100644
--- a/consensus/types/src/beacon_state.rs
+++ b/consensus/types/src/beacon_state.rs
@@ -125,6 +125,8 @@ pub enum Error {
         current_epoch: Epoch,
         epoch: Epoch,
     },
+    IndexNotSupported(usize),
+    MerkleTreeError(merkle_proof::MerkleTreeError),
 }
 
 /// Control whether an epoch-indexed field can be indexed at the next epoch or not.
@@ -1735,6 +1737,57 @@ impl<T: EthSpec> BeaconState<T> {
         };
         Ok(sync_committee)
     }
+
+    pub fn compute_merkle_proof(
+        &mut self,
+        generalized_index: usize,
+    ) -> Result<Vec<Hash256>, Error> {
+        // 1. Convert generalized index to field index.
+        let field_index = match generalized_index {
+            light_client_update::CURRENT_SYNC_COMMITTEE_INDEX
+            | light_client_update::NEXT_SYNC_COMMITTEE_INDEX => {
+                // Sync committees are top-level fields, subtract off the generalized indices
+                // for the internal nodes. Result should be 22 or 23, the field offset of the committee
+                // in the `BeaconState`:
+                // https://github.com/ethereum/consensus-specs/blob/dev/specs/altair/beacon-chain.md#beaconstate
+                generalized_index
+                    .checked_sub(tree_hash_cache::NUM_BEACON_STATE_HASH_TREE_ROOT_LEAVES)
+                    .ok_or(Error::IndexNotSupported(generalized_index))?
+            }
+            light_client_update::FINALIZED_ROOT_INDEX => {
+                // Finalized root is the right child of `finalized_checkpoint`, divide by two to get
+                // the generalized index of `state.finalized_checkpoint`.
+                let finalized_checkpoint_generalized_index = generalized_index / 2;
+                // Subtract off the internal nodes. Result should be 105/2 - 32 = 20 which matches
+                // position of `finalized_checkpoint` in `BeaconState`.
+                finalized_checkpoint_generalized_index
+                    .checked_sub(tree_hash_cache::NUM_BEACON_STATE_HASH_TREE_ROOT_LEAVES)
+                    .ok_or(Error::IndexNotSupported(generalized_index))?
+            }
+            _ => return Err(Error::IndexNotSupported(generalized_index)),
+        };
+
+        // 2. Get all `BeaconState` leaves.
+        let mut cache = self
+            .tree_hash_cache_mut()
+            .take()
+            .ok_or(Error::TreeHashCacheNotInitialized)?;
+        let leaves = cache.recalculate_tree_hash_leaves(self)?;
+        self.tree_hash_cache_mut().restore(cache);
+
+        // 3. Make deposit tree.
+        // Use the depth of the `BeaconState` fields (i.e. `log2(32) = 5`).
+        let depth = light_client_update::CURRENT_SYNC_COMMITTEE_PROOF_LEN;
+        let tree = merkle_proof::MerkleTree::create(&leaves, depth);
+        let (_, mut proof) = tree.generate_proof(field_index, depth)?;
+
+        // 4. If we're proving the finalized root, patch in the finalized epoch to complete the proof.
+        if generalized_index == light_client_update::FINALIZED_ROOT_INDEX {
+            proof.insert(0, self.finalized_checkpoint().epoch.tree_hash_root());
+        }
+
+        Ok(proof)
+    }
 }
 
 impl From<RelativeEpochError> for Error {
@@ -1767,6 +1820,12 @@ impl From<tree_hash::Error> for Error {
     }
 }
 
+impl From<merkle_proof::MerkleTreeError> for Error {
+    fn from(e: merkle_proof::MerkleTreeError) -> Error {
+        Error::MerkleTreeError(e)
+    }
+}
+
 impl From<ArithError> for Error {
     fn from(e: ArithError) -> Error {
         Error::ArithError(e)
diff --git a/consensus/types/src/beacon_state/tree_hash_cache.rs b/consensus/types/src/beacon_state/tree_hash_cache.rs
index e50265e66..30dd9f8d6 100644
--- a/consensus/types/src/beacon_state/tree_hash_cache.rs
+++ b/consensus/types/src/beacon_state/tree_hash_cache.rs
@@ -18,7 +18,7 @@ use tree_hash::{mix_in_length, MerkleHasher, TreeHash};
 ///
 /// This constant is set with the assumption that there are `> 16` and `<= 32` fields on the
 /// `BeaconState`. **Tree hashing will fail if this value is set incorrectly.**
-const NUM_BEACON_STATE_HASH_TREE_ROOT_LEAVES: usize = 32;
+pub const NUM_BEACON_STATE_HASH_TREE_ROOT_LEAVES: usize = 32;
 
 /// The number of nodes in the Merkle tree of a validator record.
 const NODES_PER_VALIDATOR: usize = 15;
@@ -210,6 +210,90 @@ impl<T: EthSpec> BeaconTreeHashCacheInner<T> {
         }
     }
 
+    pub fn recalculate_tree_hash_leaves(
+        &mut self,
+        state: &BeaconState<T>,
+    ) -> Result<Vec<Hash256>, Error> {
+        let mut leaves = vec![
+            // Genesis data leaves.
+            state.genesis_time().tree_hash_root(),
+            state.genesis_validators_root().tree_hash_root(),
+            // Current fork data leaves.
+            state.slot().tree_hash_root(),
+            state.fork().tree_hash_root(),
+            state.latest_block_header().tree_hash_root(),
+            // Roots leaves.
+            state
+                .block_roots()
+                .recalculate_tree_hash_root(&mut self.fixed_arena, &mut self.block_roots)?,
+            state
+                .state_roots()
+                .recalculate_tree_hash_root(&mut self.fixed_arena, &mut self.state_roots)?,
+            state
+                .historical_roots()
+                .recalculate_tree_hash_root(&mut self.fixed_arena, &mut self.historical_roots)?,
+            // Eth1 Data leaves.
+            state.eth1_data().tree_hash_root(),
+            self.eth1_data_votes.recalculate_tree_hash_root(state)?,
+            state.eth1_deposit_index().tree_hash_root(),
+            // Validator leaves.
+            self.validators
+                .recalculate_tree_hash_root(state.validators())?,
+            state
+                .balances()
+                .recalculate_tree_hash_root(&mut self.balances_arena, &mut self.balances)?,
+            state
+                .randao_mixes()
+                .recalculate_tree_hash_root(&mut self.fixed_arena, &mut self.randao_mixes)?,
+            state
+                .slashings()
+                .recalculate_tree_hash_root(&mut self.slashings_arena, &mut self.slashings)?,
+        ];
+        // Participation
+        if let BeaconState::Base(state) = state {
+            leaves.push(state.previous_epoch_attestations.tree_hash_root());
+            leaves.push(state.current_epoch_attestations.tree_hash_root());
+        } else {
+            leaves.push(
+                self.previous_epoch_participation
+                    .recalculate_tree_hash_root(&ParticipationList::new(
+                        state.previous_epoch_participation()?,
+                    ))?,
+            );
+            leaves.push(
+                self.current_epoch_participation
+                    .recalculate_tree_hash_root(&ParticipationList::new(
+                        state.current_epoch_participation()?,
+                    ))?,
+            );
+        }
+        // Checkpoint leaves
+        leaves.push(state.justification_bits().tree_hash_root());
+        leaves.push(state.previous_justified_checkpoint().tree_hash_root());
+        leaves.push(state.current_justified_checkpoint().tree_hash_root());
+        leaves.push(state.finalized_checkpoint().tree_hash_root());
+        // Inactivity & light-client sync committees (Altair and later).
+        if let Ok(inactivity_scores) = state.inactivity_scores() {
+            leaves.push(
+                self.inactivity_scores
+                    .recalculate_tree_hash_root(inactivity_scores)?,
+            );
+        }
+        if let Ok(current_sync_committee) = state.current_sync_committee() {
+            leaves.push(current_sync_committee.tree_hash_root());
+        }
+
+        if let Ok(next_sync_committee) = state.next_sync_committee() {
+            leaves.push(next_sync_committee.tree_hash_root());
+        }
+
+        // Execution payload (merge and later).
+        if let Ok(payload_header) = state.latest_execution_payload_header() {
+            leaves.push(payload_header.tree_hash_root());
+        }
+        Ok(leaves)
+    }
+
     /// Updates the cache and returns the tree hash root for the given `state`.
     ///
     /// The provided `state` should be a descendant of the last `state` given to this function, or
@@ -246,121 +330,9 @@ impl<T: EthSpec> BeaconTreeHashCacheInner<T> {
 
         let mut hasher = MerkleHasher::with_leaves(NUM_BEACON_STATE_HASH_TREE_ROOT_LEAVES);
 
-        hasher.write(state.genesis_time().tree_hash_root().as_bytes())?;
-        hasher.write(state.genesis_validators_root().tree_hash_root().as_bytes())?;
-        hasher.write(state.slot().tree_hash_root().as_bytes())?;
-        hasher.write(state.fork().tree_hash_root().as_bytes())?;
-        hasher.write(state.latest_block_header().tree_hash_root().as_bytes())?;
-        hasher.write(
-            state
-                .block_roots()
-                .recalculate_tree_hash_root(&mut self.fixed_arena, &mut self.block_roots)?
-                .as_bytes(),
-        )?;
-        hasher.write(
-            state
-                .state_roots()
-                .recalculate_tree_hash_root(&mut self.fixed_arena, &mut self.state_roots)?
-                .as_bytes(),
-        )?;
-        hasher.write(
-            state
-                .historical_roots()
-                .recalculate_tree_hash_root(&mut self.fixed_arena, &mut self.historical_roots)?
-                .as_bytes(),
-        )?;
-        hasher.write(state.eth1_data().tree_hash_root().as_bytes())?;
-        hasher.write(
-            self.eth1_data_votes
-                .recalculate_tree_hash_root(state)?
-                .as_bytes(),
-        )?;
-        hasher.write(state.eth1_deposit_index().tree_hash_root().as_bytes())?;
-        hasher.write(
-            self.validators
-                .recalculate_tree_hash_root(state.validators())?
-                .as_bytes(),
-        )?;
-        hasher.write(
-            state
-                .balances()
-                .recalculate_tree_hash_root(&mut self.balances_arena, &mut self.balances)?
-                .as_bytes(),
-        )?;
-        hasher.write(
-            state
-                .randao_mixes()
-                .recalculate_tree_hash_root(&mut self.fixed_arena, &mut self.randao_mixes)?
-                .as_bytes(),
-        )?;
-        hasher.write(
-            state
-                .slashings()
-                .recalculate_tree_hash_root(&mut self.slashings_arena, &mut self.slashings)?
-                .as_bytes(),
-        )?;
-
-        // Participation
-        if let BeaconState::Base(state) = state {
-            hasher.write(
-                state
-                    .previous_epoch_attestations
-                    .tree_hash_root()
-                    .as_bytes(),
-            )?;
-            hasher.write(state.current_epoch_attestations.tree_hash_root().as_bytes())?;
-        } else {
-            hasher.write(
-                self.previous_epoch_participation
-                    .recalculate_tree_hash_root(&ParticipationList::new(
-                        state.previous_epoch_participation()?,
-                    ))?
-                    .as_bytes(),
-            )?;
-            hasher.write(
-                self.current_epoch_participation
-                    .recalculate_tree_hash_root(&ParticipationList::new(
-                        state.current_epoch_participation()?,
-                    ))?
-                    .as_bytes(),
-            )?;
-        }
-
-        hasher.write(state.justification_bits().tree_hash_root().as_bytes())?;
-        hasher.write(
-            state
-                .previous_justified_checkpoint()
-                .tree_hash_root()
-                .as_bytes(),
-        )?;
-        hasher.write(
-            state
-                .current_justified_checkpoint()
-                .tree_hash_root()
-                .as_bytes(),
-        )?;
-        hasher.write(state.finalized_checkpoint().tree_hash_root().as_bytes())?;
-
-        // Inactivity & light-client sync committees (Altair and later).
-        if let Ok(inactivity_scores) = state.inactivity_scores() {
-            hasher.write(
-                self.inactivity_scores
-                    .recalculate_tree_hash_root(inactivity_scores)?
-                    .as_bytes(),
-            )?;
-        }
-
-        if let Ok(current_sync_committee) = state.current_sync_committee() {
-            hasher.write(current_sync_committee.tree_hash_root().as_bytes())?;
-        }
-
-        if let Ok(next_sync_committee) = state.next_sync_committee() {
-            hasher.write(next_sync_committee.tree_hash_root().as_bytes())?;
-        }
-
-        // Execution payload (merge and later).
-        if let Ok(payload_header) = state.latest_execution_payload_header() {
-            hasher.write(payload_header.tree_hash_root().as_bytes())?;
+        let leaves = self.recalculate_tree_hash_leaves(state)?;
+        for leaf in leaves {
+            hasher.write(leaf.as_bytes())?;
         }
 
         // Withdrawal indices (Capella and later).
diff --git a/consensus/types/src/chain_spec.rs b/consensus/types/src/chain_spec.rs
index ee108b6cf..9a8c4bb6f 100644
--- a/consensus/types/src/chain_spec.rs
+++ b/consensus/types/src/chain_spec.rs
@@ -844,7 +844,7 @@ impl ChainSpec {
             domain_sync_committee_selection_proof: 8,
             domain_contribution_and_proof: 9,
             altair_fork_version: [0x01, 0x00, 0x00, 0x64],
-            altair_fork_epoch: Some(Epoch::new(256)),
+            altair_fork_epoch: Some(Epoch::new(512)),
 
             /*
              * Merge hard fork params
@@ -855,14 +855,11 @@ impl ChainSpec {
                 .expect("pow does not overflow"),
             proportional_slashing_multiplier_bellatrix: 3,
             bellatrix_fork_version: [0x02, 0x00, 0x00, 0x64],
-            bellatrix_fork_epoch: None,
-            terminal_total_difficulty: Uint256::MAX
-                .checked_sub(Uint256::from(2u64.pow(10)))
-                .expect("subtraction does not overflow")
-                // Add 1 since the spec declares `2**256 - 2**10` and we use
-                // `Uint256::MAX` which is `2*256- 1`.
-                .checked_add(Uint256::one())
-                .expect("addition does not overflow"),
+            bellatrix_fork_epoch: Some(Epoch::new(385536)),
+            terminal_total_difficulty: Uint256::from_dec_str(
+                "8626000000000000000000058750000000000000000000",
+            )
+            .expect("terminal_total_difficulty is a valid integer"),
             terminal_block_hash: ExecutionBlockHash::zero(),
             terminal_block_hash_activation_epoch: Epoch::new(u64::MAX),
             safe_slots_to_import_optimistically: 128u64,
diff --git a/consensus/types/src/light_client_bootstrap.rs b/consensus/types/src/light_client_bootstrap.rs
index 406136d54..d2a46c04a 100644
--- a/consensus/types/src/light_client_bootstrap.rs
+++ b/consensus/types/src/light_client_bootstrap.rs
@@ -21,17 +21,15 @@ pub struct LightClientBootstrap<T: EthSpec> {
 }
 
 impl<T: EthSpec> LightClientBootstrap<T> {
-    pub fn from_beacon_state(beacon_state: BeaconState<T>) -> Result<Self, Error> {
+    pub fn from_beacon_state(beacon_state: &mut BeaconState<T>) -> Result<Self, Error> {
         let mut header = beacon_state.latest_block_header().clone();
         header.state_root = beacon_state.tree_hash_root();
+        let current_sync_committee_branch =
+            beacon_state.compute_merkle_proof(CURRENT_SYNC_COMMITTEE_INDEX)?;
         Ok(LightClientBootstrap {
             header,
             current_sync_committee: beacon_state.current_sync_committee()?.clone(),
-            /// TODO(Giulio2002): Generate Merkle Proof, this is just empty hashes
-            current_sync_committee_branch: FixedVector::new(vec![
-                Hash256::zero();
-                CURRENT_SYNC_COMMITTEE_PROOF_LEN
-            ])?,
+            current_sync_committee_branch: FixedVector::new(current_sync_committee_branch)?,
         })
     }
 }
diff --git a/consensus/types/src/light_client_finality_update.rs b/consensus/types/src/light_client_finality_update.rs
index c93d15a1a..fe26c0fa3 100644
--- a/consensus/types/src/light_client_finality_update.rs
+++ b/consensus/types/src/light_client_finality_update.rs
@@ -31,7 +31,7 @@ impl<T: EthSpec> LightClientFinalityUpdate<T> {
         chain_spec: ChainSpec,
         beacon_state: BeaconState<T>,
         block: BeaconBlock<T>,
-        attested_state: BeaconState<T>,
+        attested_state: &mut BeaconState<T>,
         finalized_block: BeaconBlock<T>,
     ) -> Result<Self, Error> {
         let altair_fork_epoch = chain_spec
@@ -60,11 +60,12 @@ impl<T: EthSpec> LightClientFinalityUpdate<T> {
         if finalized_header.tree_hash_root() != beacon_state.finalized_checkpoint().root {
             return Err(Error::InvalidFinalizedBlock);
         }
-        // TODO(Giulio2002): compute proper merkle proofs.
+
+        let finality_branch = attested_state.compute_merkle_proof(FINALIZED_ROOT_INDEX)?;
         Ok(Self {
             attested_header: attested_header,
             finalized_header: finalized_header,
-            finality_branch: FixedVector::new(vec![Hash256::zero(); FINALIZED_ROOT_PROOF_LEN])?,
+            finality_branch: FixedVector::new(finality_branch)?,
             sync_aggregate: sync_aggregate.clone(),
             signature_slot: block.slot(),
         })
diff --git a/consensus/types/src/light_client_update.rs b/consensus/types/src/light_client_update.rs
index 38609cf1b..7d01f39bf 100644
--- a/consensus/types/src/light_client_update.rs
+++ b/consensus/types/src/light_client_update.rs
@@ -77,7 +77,7 @@ impl<T: EthSpec> LightClientUpdate<T> {
         chain_spec: ChainSpec,
         beacon_state: BeaconState<T>,
         block: BeaconBlock<T>,
-        attested_state: BeaconState<T>,
+        attested_state: &mut BeaconState<T>,
         finalized_block: BeaconBlock<T>,
     ) -> Result<Self, Error> {
         let altair_fork_epoch = chain_spec
@@ -114,16 +114,15 @@ impl<T: EthSpec> LightClientUpdate<T> {
         if finalized_header.tree_hash_root() != beacon_state.finalized_checkpoint().root {
             return Err(Error::InvalidFinalizedBlock);
         }
-        // TODO(Giulio2002): compute proper merkle proofs.
+        let next_sync_committee_branch =
+            attested_state.compute_merkle_proof(NEXT_SYNC_COMMITTEE_INDEX)?;
+        let finality_branch = attested_state.compute_merkle_proof(FINALIZED_ROOT_INDEX)?;
         Ok(Self {
             attested_header,
             next_sync_committee: attested_state.next_sync_committee()?.clone(),
-            next_sync_committee_branch: FixedVector::new(vec![
-                Hash256::zero();
-                NEXT_SYNC_COMMITTEE_PROOF_LEN
-            ])?,
+            next_sync_committee_branch: FixedVector::new(next_sync_committee_branch)?,
             finalized_header,
-            finality_branch: FixedVector::new(vec![Hash256::zero(); FINALIZED_ROOT_PROOF_LEN])?,
+            finality_branch: FixedVector::new(finality_branch)?,
             sync_aggregate: sync_aggregate.clone(),
             signature_slot: block.slot(),
         })
diff --git a/consensus/types/src/payload.rs b/consensus/types/src/payload.rs
index 2507a9f0e..33fa22737 100644
--- a/consensus/types/src/payload.rs
+++ b/consensus/types/src/payload.rs
@@ -148,8 +148,8 @@ impl<T: EthSpec> From<FullPayload<T>> for ExecutionPayload<T> {
 }
 
 impl<'a, T: EthSpec> From<FullPayloadRef<'a, T>> for ExecutionPayload<T> {
-    fn from(full_payload: FullPayloadRef<'a, T>) -> Self {
-        match full_payload {
+    fn from(full_payload_ref: FullPayloadRef<'a, T>) -> Self {
+        match full_payload_ref {
             FullPayloadRef::Merge(payload) => {
                 ExecutionPayload::Merge(payload.execution_payload.clone())
             }
@@ -163,6 +163,17 @@ impl<'a, T: EthSpec> From<FullPayloadRef<'a, T>> for ExecutionPayload<T> {
     }
 }
 
+// FIXME: can this be implemented as Deref or Clone somehow?
+impl<'a, T: EthSpec> From<FullPayloadRef<'a, T>> for FullPayload<T> {
+    fn from(full_payload_ref: FullPayloadRef<'a, T>) -> Self {
+        match full_payload_ref {
+            FullPayloadRef::Merge(payload_ref) => FullPayload::Merge(payload_ref.clone()),
+            FullPayloadRef::Capella(payload_ref) => FullPayload::Capella(payload_ref.clone()),
+            FullPayloadRef::Eip4844(payload_ref) => FullPayload::Eip4844(payload_ref.clone()),
+        }
+    }
+}
+
 impl<T: EthSpec> ExecPayload<T> for FullPayload<T> {
     fn block_type() -> BlockType {
         BlockType::Full
diff --git a/consensus/types/src/withdrawal.rs b/consensus/types/src/withdrawal.rs
index 36ee63965..c2529747c 100644
--- a/consensus/types/src/withdrawal.rs
+++ b/consensus/types/src/withdrawal.rs
@@ -10,7 +10,7 @@ use tree_hash_derive::TreeHash;
 /// Spec v0.12.1
 #[cfg_attr(feature = "arbitrary-fuzz", derive(arbitrary::Arbitrary))]
 #[derive(
-    Debug, PartialEq, Hash, Clone, Serialize, Deserialize, Encode, Decode, TreeHash, TestRandom,
+    Debug, PartialEq, Eq, Hash, Clone, Serialize, Deserialize, Encode, Decode, TreeHash, TestRandom,
 )]
 pub struct Withdrawal {
     #[serde(with = "eth2_serde_utils::quoted_u64")]
diff --git a/database_manager/src/lib.rs b/database_manager/src/lib.rs
index c0023f350..33accfc05 100644
--- a/database_manager/src/lib.rs
+++ b/database_manager/src/lib.rs
@@ -98,10 +98,9 @@ fn parse_client_config<E: EthSpec>(
     cli_args: &ArgMatches,
     _env: &Environment<E>,
 ) -> Result<ClientConfig, String> {
-    let mut client_config = ClientConfig {
-        data_dir: get_data_dir(cli_args),
-        ..Default::default()
-    };
+    let mut client_config = ClientConfig::default();
+
+    client_config.set_data_dir(get_data_dir(cli_args));
 
     if let Some(freezer_dir) = clap_utils::parse_optional(cli_args, "freezer-dir")? {
         client_config.freezer_db_path = Some(freezer_dir);
@@ -289,7 +288,7 @@ pub fn prune_payloads<E: EthSpec>(
 }
 
 /// Run the database manager, returning an error string if the operation did not succeed.
-pub fn run<T: EthSpec>(cli_args: &ArgMatches<'_>, mut env: Environment<T>) -> Result<(), String> {
+pub fn run<T: EthSpec>(cli_args: &ArgMatches<'_>, env: Environment<T>) -> Result<(), String> {
     let client_config = parse_client_config(cli_args, &env)?;
     let context = env.core_context();
     let log = context.log().clone();
diff --git a/lcli/Cargo.toml b/lcli/Cargo.toml
index 00e7fe912..edfbb436d 100644
--- a/lcli/Cargo.toml
+++ b/lcli/Cargo.toml
@@ -1,7 +1,7 @@
 [package]
 name = "lcli"
 description = "Lighthouse CLI (modeled after zcli)"
-version = "3.2.1"
+version = "3.3.0"
 authors = ["Paul Hauner <paul@paulhauner.com>"]
 edition = "2021"
 
diff --git a/lcli/src/block_root.rs b/lcli/src/block_root.rs
index 7631872c5..a47b48a30 100644
--- a/lcli/src/block_root.rs
+++ b/lcli/src/block_root.rs
@@ -37,7 +37,7 @@ use types::{EthSpec, FullPayload, SignedBeaconBlock};
 
 const HTTP_TIMEOUT: Duration = Duration::from_secs(5);
 
-pub fn run<T: EthSpec>(mut env: Environment<T>, matches: &ArgMatches) -> Result<(), String> {
+pub fn run<T: EthSpec>(env: Environment<T>, matches: &ArgMatches) -> Result<(), String> {
     let spec = &T::default_spec();
     let executor = env.core_context().executor;
 
diff --git a/lcli/src/eth1_genesis.rs b/lcli/src/eth1_genesis.rs
index 80bcff909..34144cd86 100644
--- a/lcli/src/eth1_genesis.rs
+++ b/lcli/src/eth1_genesis.rs
@@ -13,7 +13,7 @@ use types::EthSpec;
 pub const ETH1_GENESIS_UPDATE_INTERVAL: Duration = Duration::from_millis(7_000);
 
 pub fn run<T: EthSpec>(
-    mut env: Environment<T>,
+    env: Environment<T>,
     testnet_dir: PathBuf,
     matches: &ArgMatches<'_>,
 ) -> Result<(), String> {
diff --git a/lcli/src/main.rs b/lcli/src/main.rs
index 8b233d847..9d548b049 100644
--- a/lcli/src/main.rs
+++ b/lcli/src/main.rs
@@ -789,6 +789,7 @@ fn run<T: EthSpec>(
             max_log_size: 0,
             max_log_number: 0,
             compression: false,
+            is_restricted: true,
         })
         .map_err(|e| format!("should start logger: {:?}", e))?
         .build()
diff --git a/lcli/src/skip_slots.rs b/lcli/src/skip_slots.rs
index 8bd9af99a..49d1dd424 100644
--- a/lcli/src/skip_slots.rs
+++ b/lcli/src/skip_slots.rs
@@ -59,7 +59,7 @@ use types::{BeaconState, CloneConfig, EthSpec, Hash256};
 
 const HTTP_TIMEOUT: Duration = Duration::from_secs(10);
 
-pub fn run<T: EthSpec>(mut env: Environment<T>, matches: &ArgMatches) -> Result<(), String> {
+pub fn run<T: EthSpec>(env: Environment<T>, matches: &ArgMatches) -> Result<(), String> {
     let spec = &T::default_spec();
     let executor = env.core_context().executor;
 
diff --git a/lcli/src/transition_blocks.rs b/lcli/src/transition_blocks.rs
index b25cec81b..44a1772cc 100644
--- a/lcli/src/transition_blocks.rs
+++ b/lcli/src/transition_blocks.rs
@@ -94,7 +94,7 @@ struct Config {
     exclude_post_block_thc: bool,
 }
 
-pub fn run<T: EthSpec>(mut env: Environment<T>, matches: &ArgMatches) -> Result<(), String> {
+pub fn run<T: EthSpec>(env: Environment<T>, matches: &ArgMatches) -> Result<(), String> {
     let spec = &T::default_spec();
     let executor = env.core_context().executor;
 
@@ -339,6 +339,10 @@ fn do_transition<T: EthSpec>(
         .map_err(|e| format!("Unable to build caches: {:?}", e))?;
     debug!("Build all caches (again): {:?}", t.elapsed());
 
+    let mut ctxt = ConsensusContext::new(pre_state.slot())
+        .set_current_block_root(block_root)
+        .set_proposer_index(block.message().proposer_index());
+
     if !config.no_signature_verification {
         let get_pubkey = move |validator_index| {
             validator_pubkey_cache
@@ -359,18 +363,20 @@ fn do_transition<T: EthSpec>(
             get_pubkey,
             decompressor,
             &block,
-            Some(block_root),
-            Some(block.message().proposer_index()),
+            &mut ctxt,
             spec,
         )
         .map_err(|e| format!("Invalid block signature: {:?}", e))?;
         debug!("Batch verify block signatures: {:?}", t.elapsed());
+
+        // Signature verification should prime the indexed attestation cache.
+        assert_eq!(
+            ctxt.num_cached_indexed_attestations(),
+            block.message().body().attestations().len()
+        );
     }
 
     let t = Instant::now();
-    let mut ctxt = ConsensusContext::new(pre_state.slot())
-        .set_current_block_root(block_root)
-        .set_proposer_index(block.message().proposer_index());
     per_block_processing(
         &mut pre_state,
         &block,
diff --git a/lighthouse/Cargo.toml b/lighthouse/Cargo.toml
index 7864b7e82..3b4dd5753 100644
--- a/lighthouse/Cargo.toml
+++ b/lighthouse/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "lighthouse"
-version = "3.2.1"
+version = "3.3.0"
 authors = ["Sigma Prime <contact@sigmaprime.io>"]
 edition = "2021"
 autotests = false
diff --git a/lighthouse/environment/src/lib.rs b/lighthouse/environment/src/lib.rs
index 49163b96f..fad7edeb1 100644
--- a/lighthouse/environment/src/lib.rs
+++ b/lighthouse/environment/src/lib.rs
@@ -55,6 +55,7 @@ pub struct LoggerConfig {
     pub max_log_size: u64,
     pub max_log_number: usize,
     pub compression: bool,
+    pub is_restricted: bool,
 }
 impl Default for LoggerConfig {
     fn default() -> Self {
@@ -68,6 +69,7 @@ impl Default for LoggerConfig {
             max_log_size: 200,
             max_log_number: 5,
             compression: false,
+            is_restricted: true,
         }
     }
 }
@@ -257,7 +259,7 @@ impl<E: EthSpec> EnvironmentBuilder<E> {
             .rotate_size(config.max_log_size)
             .rotate_keep(config.max_log_number)
             .rotate_compress(config.compression)
-            .restrict_permissions(true)
+            .restrict_permissions(config.is_restricted)
             .build()
             .map_err(|e| format!("Unable to build file logger: {}", e))?;
 
@@ -380,7 +382,7 @@ impl<E: EthSpec> Environment<E> {
     }
 
     /// Returns a `Context` where no "service" has been added to the logger output.
-    pub fn core_context(&mut self) -> RuntimeContext<E> {
+    pub fn core_context(&self) -> RuntimeContext<E> {
         RuntimeContext {
             executor: TaskExecutor::new(
                 Arc::downgrade(self.runtime()),
@@ -395,7 +397,7 @@ impl<E: EthSpec> Environment<E> {
     }
 
     /// Returns a `Context` where the `service_name` is added to the logger output.
-    pub fn service_context(&mut self, service_name: String) -> RuntimeContext<E> {
+    pub fn service_context(&self, service_name: String) -> RuntimeContext<E> {
         RuntimeContext {
             executor: TaskExecutor::new(
                 Arc::downgrade(self.runtime()),
diff --git a/lighthouse/src/main.rs b/lighthouse/src/main.rs
index 9dc0902e0..da72204f9 100644
--- a/lighthouse/src/main.rs
+++ b/lighthouse/src/main.rs
@@ -129,6 +129,15 @@ fn main() {
                     to store old logs.")
                 .global(true),
         )
+        .arg(
+            Arg::with_name("logfile-no-restricted-perms")
+                .long("logfile-no-restricted-perms")
+                .help(
+                    "If present, log files will be generated as world-readable meaning they can be read by \
+                    any user on the machine. Note that logs can often contain sensitive information \
+                    about your validator and so this flag should be used with caution.")
+                .global(true),
+        )
         .arg(
             Arg::with_name("log-format")
                 .long("log-format")
@@ -407,6 +416,8 @@ fn run<E: EthSpec>(
 
     let logfile_compress = matches.is_present("logfile-compress");
 
+    let logfile_restricted = !matches.is_present("logfile-no-restricted-perms");
+
     // Construct the path to the log file.
     let mut log_path: Option<PathBuf> = clap_utils::parse_optional(matches, "logfile")?;
     if log_path.is_none() {
@@ -446,6 +457,7 @@ fn run<E: EthSpec>(
         max_log_size: logfile_max_size * 1_024 * 1_024,
         max_log_number: logfile_max_number,
         compression: logfile_compress,
+        is_restricted: logfile_restricted,
     };
 
     let builder = environment_builder.initialize_logger(logger_config.clone())?;
diff --git a/lighthouse/tests/beacon_node.rs b/lighthouse/tests/beacon_node.rs
index b1498f109..d39235cb1 100644
--- a/lighthouse/tests/beacon_node.rs
+++ b/lighthouse/tests/beacon_node.rs
@@ -56,7 +56,9 @@ impl CommandLineTestExec for CommandLineTest {
 fn datadir_flag() {
     CommandLineTest::new()
         .run_with_zero_port()
-        .with_config_and_dir(|config, dir| assert_eq!(config.data_dir, dir.path().join("beacon")));
+        .with_config_and_dir(|config, dir| {
+            assert_eq!(*config.data_dir(), dir.path().join("beacon"))
+        });
 }
 
 #[test]
@@ -132,6 +134,25 @@ fn fork_choice_before_proposal_timeout_zero() {
         .with_config(|config| assert_eq!(config.chain.fork_choice_before_proposal_timeout_ms, 0));
 }
 
+#[test]
+fn checkpoint_sync_url_timeout_flag() {
+    CommandLineTest::new()
+        .flag("checkpoint-sync-url-timeout", Some("300"))
+        .run_with_zero_port()
+        .with_config(|config| {
+            assert_eq!(config.chain.checkpoint_sync_url_timeout, 300);
+        });
+}
+
+#[test]
+fn checkpoint_sync_url_timeout_default() {
+    CommandLineTest::new()
+        .run_with_zero_port()
+        .with_config(|config| {
+            assert_eq!(config.chain.checkpoint_sync_url_timeout, 60);
+        });
+}
+
 #[test]
 fn paranoid_block_proposal_default() {
     CommandLineTest::new()
@@ -1527,6 +1548,23 @@ fn enabled_disable_log_timestamp_flag() {
             assert!(config.logger_config.disable_log_timestamp);
         });
 }
+#[test]
+fn logfile_restricted_perms_default() {
+    CommandLineTest::new()
+        .run_with_zero_port()
+        .with_config(|config| {
+            assert!(config.logger_config.is_restricted);
+        });
+}
+#[test]
+fn logfile_no_restricted_perms_flag() {
+    CommandLineTest::new()
+        .flag("logfile-no-restricted-perms", None)
+        .run_with_zero_port()
+        .with_config(|config| {
+            assert!(config.logger_config.is_restricted == false);
+        });
+}
 
 #[test]
 fn sync_eth1_chain_default() {
@@ -1561,3 +1599,29 @@ fn sync_eth1_chain_disable_deposit_contract_sync_flag() {
         .run_with_zero_port()
         .with_config(|config| assert_eq!(config.sync_eth1_chain, false));
 }
+
+#[test]
+fn light_client_server_default() {
+    CommandLineTest::new()
+        .run_with_zero_port()
+        .with_config(|config| assert_eq!(config.network.enable_light_client_server, false));
+}
+
+#[test]
+fn light_client_server_enabled() {
+    CommandLineTest::new()
+        .flag("light-client-server", None)
+        .run_with_zero_port()
+        .with_config(|config| assert_eq!(config.network.enable_light_client_server, true));
+}
+
+#[test]
+fn gui_flag() {
+    CommandLineTest::new()
+        .flag("gui", None)
+        .run_with_zero_port()
+        .with_config(|config| {
+            assert!(config.http_api.enabled);
+            assert!(config.validator_monitor_auto);
+        });
+}
diff --git a/testing/ef_tests/check_all_files_accessed.py b/testing/ef_tests/check_all_files_accessed.py
index 49bc920dd..04f45ac5d 100755
--- a/testing/ef_tests/check_all_files_accessed.py
+++ b/testing/ef_tests/check_all_files_accessed.py
@@ -39,10 +39,10 @@ excluded_paths = [
     "tests/.*/.*/ssz_static/LightClientOptimistic",
     # LightClientFinalityUpdate
     "tests/.*/.*/ssz_static/LightClientFinalityUpdate",
-    # Merkle-proof tests for light clients
-    "tests/.*/.*/merkle/single_proof",
     # Eip4844 tests are disabled for now.
     "tests/.*/eip4844",
+    # Capella tests are disabled for now.
+    "tests/.*/capella",
     # One of the EF researchers likes to pack the tarballs on a Mac
     ".*\.DS_Store.*",
     # More Mac weirdness.
diff --git a/testing/ef_tests/src/cases.rs b/testing/ef_tests/src/cases.rs
index ae70f1e07..216912a4f 100644
--- a/testing/ef_tests/src/cases.rs
+++ b/testing/ef_tests/src/cases.rs
@@ -18,6 +18,7 @@ mod fork;
 mod fork_choice;
 mod genesis_initialization;
 mod genesis_validity;
+mod merkle_proof_validity;
 mod operations;
 mod rewards;
 mod sanity_blocks;
@@ -41,6 +42,7 @@ pub use epoch_processing::*;
 pub use fork::ForkTest;
 pub use genesis_initialization::*;
 pub use genesis_validity::*;
+pub use merkle_proof_validity::*;
 pub use operations::*;
 pub use rewards::RewardsTest;
 pub use sanity_blocks::*;
diff --git a/testing/ef_tests/src/cases/fork_choice.rs b/testing/ef_tests/src/cases/fork_choice.rs
index 8faf4db82..039efb368 100644
--- a/testing/ef_tests/src/cases/fork_choice.rs
+++ b/testing/ef_tests/src/cases/fork_choice.rs
@@ -7,7 +7,7 @@ use beacon_chain::{
         obtain_indexed_attestation_and_committees_per_slot, VerifiedAttestation,
     },
     test_utils::{BeaconChainHarness, EphemeralHarnessType},
-    BeaconChainTypes, CachedHead, CountUnrealized,
+    BeaconChainTypes, CachedHead, CountUnrealized, NotifyExecutionLayer,
 };
 use execution_layer::{json_structures::JsonPayloadStatusV1Status, PayloadStatusV1};
 use serde::Deserialize;
@@ -388,6 +388,7 @@ impl<E: EthSpec> Tester<E> {
             block_root,
             block.clone(),
             CountUnrealized::False,
+            NotifyExecutionLayer::Yes,
         ))?;
         if result.is_ok() != valid {
             return Err(Error::DidntFail(format!(
diff --git a/testing/ef_tests/src/cases/merkle_proof_validity.rs b/testing/ef_tests/src/cases/merkle_proof_validity.rs
new file mode 100644
index 000000000..a57abc2e0
--- /dev/null
+++ b/testing/ef_tests/src/cases/merkle_proof_validity.rs
@@ -0,0 +1,87 @@
+use super::*;
+use crate::decode::{ssz_decode_state, yaml_decode_file};
+use serde_derive::Deserialize;
+use std::path::Path;
+use tree_hash::Hash256;
+use types::{BeaconState, EthSpec, ForkName};
+
+#[derive(Debug, Clone, Deserialize)]
+pub struct Metadata {
+    #[serde(rename(deserialize = "description"))]
+    _description: String,
+}
+
+#[derive(Debug, Clone, Deserialize)]
+pub struct MerkleProof {
+    pub leaf: Hash256,
+    pub leaf_index: usize,
+    pub branch: Vec<Hash256>,
+}
+
+#[derive(Debug, Clone, Deserialize)]
+#[serde(bound = "E: EthSpec")]
+pub struct MerkleProofValidity<E: EthSpec> {
+    pub metadata: Option<Metadata>,
+    pub state: BeaconState<E>,
+    pub merkle_proof: MerkleProof,
+}
+
+impl<E: EthSpec> LoadCase for MerkleProofValidity<E> {
+    fn load_from_dir(path: &Path, fork_name: ForkName) -> Result<Self, Error> {
+        let spec = &testing_spec::<E>(fork_name);
+        let state = ssz_decode_state(&path.join("state.ssz_snappy"), spec)?;
+        let merkle_proof = yaml_decode_file(&path.join("proof.yaml"))?;
+        // Metadata does not exist in these tests but it is left like this just in case.
+        let meta_path = path.join("meta.yaml");
+        let metadata = if meta_path.exists() {
+            Some(yaml_decode_file(&meta_path)?)
+        } else {
+            None
+        };
+
+        Ok(Self {
+            metadata,
+            state,
+            merkle_proof,
+        })
+    }
+}
+
+impl<E: EthSpec> Case for MerkleProofValidity<E> {
+    fn result(&self, _case_index: usize, _fork_name: ForkName) -> Result<(), Error> {
+        let mut state = self.state.clone();
+        state.initialize_tree_hash_cache();
+        let proof = match state.compute_merkle_proof(self.merkle_proof.leaf_index) {
+            Ok(proof) => proof,
+            Err(_) => {
+                return Err(Error::FailedToParseTest(
+                    "Could not retrieve merkle proof".to_string(),
+                ))
+            }
+        };
+        let proof_len = proof.len();
+        let branch_len = self.merkle_proof.branch.len();
+        if proof_len != branch_len {
+            return Err(Error::NotEqual(format!(
+                "Branches not equal in length computed: {}, expected {}",
+                proof_len, branch_len
+            )));
+        }
+
+        for (i, proof_leaf) in proof.iter().enumerate().take(proof_len) {
+            let expected_leaf = self.merkle_proof.branch[i];
+            if *proof_leaf != expected_leaf {
+                return Err(Error::NotEqual(format!(
+                    "Leaves not equal in merke proof computed: {}, expected: {}",
+                    hex::encode(proof_leaf),
+                    hex::encode(expected_leaf)
+                )));
+            }
+        }
+
+        // Tree hash cache should still be initialized (not dropped).
+        assert!(state.tree_hash_cache().is_initialized());
+
+        Ok(())
+    }
+}
diff --git a/testing/ef_tests/src/cases/operations.rs b/testing/ef_tests/src/cases/operations.rs
index 53d1e49b6..a5832c64a 100644
--- a/testing/ef_tests/src/cases/operations.rs
+++ b/testing/ef_tests/src/cases/operations.rs
@@ -90,7 +90,6 @@ impl<E: EthSpec> Operation<E> for Attestation<E> {
         _: &Operations<E, Self>,
     ) -> Result<(), BlockProcessingError> {
         let mut ctxt = ConsensusContext::new(state.slot());
-        let proposer_index = ctxt.get_proposer_index(state, spec)?;
         match state {
             BeaconState::Base(_) => base::process_attestations(
                 state,
@@ -102,14 +101,9 @@ impl<E: EthSpec> Operation<E> for Attestation<E> {
             BeaconState::Altair(_)
             | BeaconState::Merge(_)
             | BeaconState::Capella(_)
-            | BeaconState::Eip4844(_) => altair::process_attestation(
-                state,
-                self,
-                0,
-                proposer_index,
-                VerifySignatures::True,
-                spec,
-            ),
+            | BeaconState::Eip4844(_) => {
+                altair::process_attestation(state, self, 0, &mut ctxt, VerifySignatures::True, spec)
+            }
         }
     }
 }
diff --git a/testing/ef_tests/src/handler.rs b/testing/ef_tests/src/handler.rs
index b4dca42bc..7c73ea52d 100644
--- a/testing/ef_tests/src/handler.rs
+++ b/testing/ef_tests/src/handler.rs
@@ -627,6 +627,30 @@ impl<E: EthSpec + TypeName> Handler for GenesisInitializationHandler<E> {
     }
 }
 
+#[derive(Derivative)]
+#[derivative(Default(bound = ""))]
+pub struct MerkleProofValidityHandler<E>(PhantomData<E>);
+
+impl<E: EthSpec + TypeName> Handler for MerkleProofValidityHandler<E> {
+    type Case = cases::MerkleProofValidity<E>;
+
+    fn config_name() -> &'static str {
+        E::name()
+    }
+
+    fn runner_name() -> &'static str {
+        "light_client"
+    }
+
+    fn handler_name(&self) -> String {
+        "single_merkle_proof".into()
+    }
+
+    fn is_enabled_for_fork(&self, fork_name: ForkName) -> bool {
+        fork_name != ForkName::Base
+    }
+}
+
 #[derive(Derivative)]
 #[derivative(Default(bound = ""))]
 pub struct OperationsHandler<E, O>(PhantomData<(E, O)>);
diff --git a/testing/ef_tests/tests/tests.rs b/testing/ef_tests/tests/tests.rs
index adaabf84d..bb5975d7c 100644
--- a/testing/ef_tests/tests/tests.rs
+++ b/testing/ef_tests/tests/tests.rs
@@ -532,6 +532,11 @@ fn genesis_validity() {
     // Note: there are no genesis validity tests for mainnet
 }
 
+#[test]
+fn merkle_proof_validity() {
+    MerkleProofValidityHandler::<MainnetEthSpec>::default().run();
+}
+
 #[test]
 fn rewards() {
     for handler in &["basic", "leak", "random"] {
diff --git a/testing/execution_engine_integration/src/nethermind.rs b/testing/execution_engine_integration/src/nethermind.rs
index 1fe7bf0f0..f643fbd5f 100644
--- a/testing/execution_engine_integration/src/nethermind.rs
+++ b/testing/execution_engine_integration/src/nethermind.rs
@@ -8,7 +8,10 @@ use std::process::{Child, Command, Output};
 use tempfile::TempDir;
 use unused_port::unused_tcp_port;
 
-const NETHERMIND_BRANCH: &str = "master";
+/// We've pinned the Nethermind version since our method of using the `master` branch to
+/// find the latest tag isn't working. It appears Nethermind don't always tag on `master`.
+/// We should fix this so we always pull the latest version of Nethermind.
+const NETHERMIND_BRANCH: &str = "release/1.14.6";
 const NETHERMIND_REPO_URL: &str = "https://github.com/NethermindEth/nethermind";
 
 fn build_result(repo_dir: &Path) -> Output {
diff --git a/testing/execution_engine_integration/src/test_rig.rs b/testing/execution_engine_integration/src/test_rig.rs
index 9ef96687a..944e2fef6 100644
--- a/testing/execution_engine_integration/src/test_rig.rs
+++ b/testing/execution_engine_integration/src/test_rig.rs
@@ -4,8 +4,7 @@ use crate::execution_engine::{
 use crate::transactions::transactions;
 use ethers_providers::Middleware;
 use execution_layer::{
-    BuilderParams, ChainHealth, ExecutionLayer, PayloadAttributes, PayloadAttributesV1,
-    PayloadStatus,
+    BuilderParams, ChainHealth, ExecutionLayer, PayloadAttributes, PayloadStatus,
 };
 use fork_choice::ForkchoiceUpdateParameters;
 use reqwest::{header::CONTENT_TYPE, Client};
@@ -19,7 +18,7 @@ use types::{
     Address, ChainSpec, EthSpec, ExecutionBlockHash, ExecutionPayload, ForkName, FullPayload,
     Hash256, MainnetEthSpec, PublicKeyBytes, Slot, Uint256,
 };
-const EXECUTION_ENGINE_START_TIMEOUT: Duration = Duration::from_secs(20);
+const EXECUTION_ENGINE_START_TIMEOUT: Duration = Duration::from_secs(30);
 
 struct ExecutionPair<E, T: EthSpec> {
     /// The Lighthouse `ExecutionLayer` struct, connected to the `execution_engine` via HTTP.
@@ -279,11 +278,8 @@ impl<E: GenericExecutionEngine> TestRig<E> {
                 Slot::new(1), // Insert proposer for the next slot
                 head_root,
                 proposer_index,
-                PayloadAttributes::V1(PayloadAttributesV1 {
-                    timestamp,
-                    prev_randao,
-                    suggested_fee_recipient: Address::zero(),
-                }),
+                // TODO: think about how to test different forks
+                PayloadAttributes::new(timestamp, prev_randao, Address::zero(), None),
             )
             .await;
 
@@ -316,20 +312,23 @@ impl<E: GenericExecutionEngine> TestRig<E> {
             slot: Slot::new(0),
             chain_health: ChainHealth::Healthy,
         };
+        let suggested_fee_recipient = self
+            .ee_a
+            .execution_layer
+            .get_suggested_fee_recipient(proposer_index)
+            .await;
+        let payload_attributes =
+            PayloadAttributes::new(timestamp, prev_randao, suggested_fee_recipient, None);
         let valid_payload = self
             .ee_a
             .execution_layer
             .get_payload::<FullPayload<MainnetEthSpec>>(
                 parent_hash,
-                timestamp,
-                prev_randao,
-                proposer_index,
+                &payload_attributes,
                 forkchoice_update_params,
                 builder_params,
                 // FIXME: think about how to test other forks
                 ForkName::Merge,
-                #[cfg(feature = "withdrawals")]
-                None,
                 &self.spec,
             )
             .await
@@ -444,20 +443,23 @@ impl<E: GenericExecutionEngine> TestRig<E> {
             slot: Slot::new(0),
             chain_health: ChainHealth::Healthy,
         };
+        let suggested_fee_recipient = self
+            .ee_a
+            .execution_layer
+            .get_suggested_fee_recipient(proposer_index)
+            .await;
+        let payload_attributes =
+            PayloadAttributes::new(timestamp, prev_randao, suggested_fee_recipient, None);
         let second_payload = self
             .ee_a
             .execution_layer
             .get_payload::<FullPayload<MainnetEthSpec>>(
                 parent_hash,
-                timestamp,
-                prev_randao,
-                proposer_index,
+                &payload_attributes,
                 forkchoice_update_params,
                 builder_params,
                 // FIXME: think about how to test other forks
                 ForkName::Merge,
-                #[cfg(feature = "withdrawals")]
-                None,
                 &self.spec,
             )
             .await
@@ -487,11 +489,9 @@ impl<E: GenericExecutionEngine> TestRig<E> {
          */
         let head_block_hash = valid_payload.block_hash();
         let finalized_block_hash = ExecutionBlockHash::zero();
-        let payload_attributes = PayloadAttributes::V1(PayloadAttributesV1 {
-            timestamp: second_payload.timestamp() + 1,
-            prev_randao: Hash256::zero(),
-            suggested_fee_recipient: Address::zero(),
-        });
+        // TODO: think about how to handle different forks
+        let payload_attributes =
+            PayloadAttributes::new(timestamp, prev_randao, Address::zero(), None);
         let slot = Slot::new(42);
         let head_block_root = Hash256::repeat_byte(100);
         let validator_index = 0;
diff --git a/testing/node_test_rig/src/lib.rs b/testing/node_test_rig/src/lib.rs
index 0933bff4c..d0a4ef949 100644
--- a/testing/node_test_rig/src/lib.rs
+++ b/testing/node_test_rig/src/lib.rs
@@ -48,7 +48,7 @@ impl<E: EthSpec> LocalBeaconNode<E> {
             .tempdir()
             .expect("should create temp directory for client datadir");
 
-        client_config.data_dir = datadir.path().into();
+        client_config.set_data_dir(datadir.path().into());
         client_config.network.network_dir = PathBuf::from(datadir.path()).join("network");
 
         ProductionBeaconNode::new(context, client_config)
diff --git a/testing/simulator/src/eth1_sim.rs b/testing/simulator/src/eth1_sim.rs
index 3d59013f2..8284bff60 100644
--- a/testing/simulator/src/eth1_sim.rs
+++ b/testing/simulator/src/eth1_sim.rs
@@ -67,6 +67,7 @@ pub fn run_eth1_sim(matches: &ArgMatches) -> Result<(), String> {
             max_log_size: 0,
             max_log_number: 0,
             compression: false,
+            is_restricted: true,
         })?
         .multi_threaded_tokio_runtime()?
         .build()?;
diff --git a/testing/simulator/src/no_eth1_sim.rs b/testing/simulator/src/no_eth1_sim.rs
index 06f9e9a4f..53c4447da 100644
--- a/testing/simulator/src/no_eth1_sim.rs
+++ b/testing/simulator/src/no_eth1_sim.rs
@@ -52,6 +52,7 @@ pub fn run_no_eth1_sim(matches: &ArgMatches) -> Result<(), String> {
             max_log_size: 0,
             max_log_number: 0,
             compression: false,
+            is_restricted: true,
         })?
         .multi_threaded_tokio_runtime()?
         .build()?;
diff --git a/testing/simulator/src/sync_sim.rs b/testing/simulator/src/sync_sim.rs
index 00e439e4c..1c8b41f05 100644
--- a/testing/simulator/src/sync_sim.rs
+++ b/testing/simulator/src/sync_sim.rs
@@ -56,6 +56,7 @@ fn syncing_sim(
             max_log_size: 0,
             max_log_number: 0,
             compression: false,
+            is_restricted: true,
         })?
         .multi_threaded_tokio_runtime()?
         .build()?;
diff --git a/validator_client/Cargo.toml b/validator_client/Cargo.toml
index 8a3c8303a..ada023f8c 100644
--- a/validator_client/Cargo.toml
+++ b/validator_client/Cargo.toml
@@ -59,3 +59,6 @@ task_executor = { path = "../common/task_executor" }
 reqwest = { version = "0.11.0", features = ["json","stream"] }
 url = "2.2.2"
 malloc_utils = { path = "../common/malloc_utils" }
+sysinfo = "0.26.5"
+system_health = { path = "../common/system_health" }
+
diff --git a/validator_client/src/http_api/mod.rs b/validator_client/src/http_api/mod.rs
index e9c7bf69d..df5d0c606 100644
--- a/validator_client/src/http_api/mod.rs
+++ b/validator_client/src/http_api/mod.rs
@@ -16,6 +16,7 @@ use eth2::lighthouse_vc::{
     types::{self as api_types, GenericResponse, PublicKey, PublicKeyBytes},
 };
 use lighthouse_version::version_with_platform;
+use parking_lot::RwLock;
 use serde::{Deserialize, Serialize};
 use slog::{crit, info, warn, Logger};
 use slot_clock::SlotClock;
@@ -24,6 +25,8 @@ use std::marker::PhantomData;
 use std::net::{IpAddr, Ipv4Addr, SocketAddr};
 use std::path::PathBuf;
 use std::sync::Arc;
+use sysinfo::{System, SystemExt};
+use system_health::observe_system_health_vc;
 use task_executor::TaskExecutor;
 use types::{ChainSpec, ConfigAndPreset, EthSpec};
 use validator_dir::Builder as ValidatorDirBuilder;
@@ -183,6 +186,35 @@ pub fn serve<T: 'static + SlotClock + Clone, E: EthSpec>(
     let api_token_path_inner = api_token_path.clone();
     let api_token_path_filter = warp::any().map(move || api_token_path_inner.clone());
 
+    // Create a `warp` filter that provides access to local system information.
+    let system_info = Arc::new(RwLock::new(sysinfo::System::new()));
+    {
+        // grab write access for initialisation
+        let mut system_info = system_info.write();
+        system_info.refresh_disks_list();
+        system_info.refresh_networks_list();
+    } // end lock
+
+    let system_info_filter =
+        warp::any()
+            .map(move || system_info.clone())
+            .map(|sysinfo: Arc<RwLock<System>>| {
+                {
+                    // refresh stats
+                    let mut sysinfo_lock = sysinfo.write();
+                    sysinfo_lock.refresh_memory();
+                    sysinfo_lock.refresh_cpu_specifics(sysinfo::CpuRefreshKind::everything());
+                    sysinfo_lock.refresh_cpu();
+                    sysinfo_lock.refresh_system();
+                    sysinfo_lock.refresh_networks();
+                    sysinfo_lock.refresh_disks();
+                } // end lock
+                sysinfo
+            });
+
+    let app_start = std::time::Instant::now();
+    let app_start_filter = warp::any().map(move || app_start);
+
     // GET lighthouse/version
     let get_node_version = warp::path("lighthouse")
         .and(warp::path("version"))
@@ -279,6 +311,24 @@ pub fn serve<T: 'static + SlotClock + Clone, E: EthSpec>(
             },
         );
 
+    // GET lighthouse/ui/health
+    let get_lighthouse_ui_health = warp::path("lighthouse")
+        .and(warp::path("ui"))
+        .and(warp::path("health"))
+        .and(warp::path::end())
+        .and(system_info_filter)
+        .and(app_start_filter)
+        .and(validator_dir_filter.clone())
+        .and(signer.clone())
+        .and_then(|sysinfo, app_start: std::time::Instant, val_dir, signer| {
+            blocking_signed_json_task(signer, move || {
+                let app_uptime = app_start.elapsed().as_secs() as u64;
+                Ok(api_types::GenericResponse::from(observe_system_health_vc(
+                    sysinfo, val_dir, app_uptime,
+                )))
+            })
+        });
+
     // POST lighthouse/validators/
     let post_validators = warp::path("lighthouse")
         .and(warp::path("validators"))
@@ -894,6 +944,7 @@ pub fn serve<T: 'static + SlotClock + Clone, E: EthSpec>(
                         .or(get_lighthouse_spec)
                         .or(get_lighthouse_validators)
                         .or(get_lighthouse_validators_pubkey)
+                        .or(get_lighthouse_ui_health)
                         .or(get_fee_recipient)
                         .or(get_gas_limit)
                         .or(get_std_keystores)
diff --git a/validator_client/src/sync_committee_service.rs b/validator_client/src/sync_committee_service.rs
index 5b9594530..3647396ed 100644
--- a/validator_client/src/sync_committee_service.rs
+++ b/validator_client/src/sync_committee_service.rs
@@ -174,39 +174,40 @@ impl<T: SlotClock + 'static, E: EthSpec> SyncCommitteeService<T, E> {
             return Ok(());
         }
 
-        // Fetch `block_root` and `execution_optimistic` for `SyncCommitteeContribution`.
+        // Fetch `block_root` with non optimistic execution for `SyncCommitteeContribution`.
         let response = self
             .beacon_nodes
-            .first_success(RequireSynced::Yes, OfflineOnFailure::Yes,|beacon_node| async move {
-                beacon_node.get_beacon_blocks_root(BlockId::Head).await
-            })
-            .await
-            .map_err(|e| e.to_string())?
-            .ok_or_else(|| format!("No block root found for slot {}", slot))?;
+            .first_success(
+                RequireSynced::Yes,
+                OfflineOnFailure::Yes,
+                |beacon_node| async move {
+                    match beacon_node.get_beacon_blocks_root(BlockId::Head).await {
+                        Ok(Some(block)) if block.execution_optimistic == Some(false) => {
+                            Ok(block)
+                        }
+                        Ok(Some(_)) => {
+                            Err(format!("To sign sync committee messages for slot {slot} a non-optimistic head block is required"))
+                        }
+                        Ok(None) => Err(format!("No block root found for slot {}", slot)),
+                        Err(e) => Err(e.to_string()),
+                    }
+                },
+            )
+            .await;
 
-        let block_root = response.data.root;
-        if let Some(execution_optimistic) = response.execution_optimistic {
-            if execution_optimistic {
+        let block_root = match response {
+            Ok(block) => block.data.root,
+            Err(errs) => {
                 warn!(
                     log,
-                    "Refusing to sign sync committee messages for optimistic head block";
+                    "Refusing to sign sync committee messages for an optimistic head block or \
+                    a block head with unknown optimistic status";
+                    "errors" => errs.to_string(),
                     "slot" => slot,
                 );
                 return Ok(());
             }
-        } else if let Some(bellatrix_fork_epoch) = self.duties_service.spec.bellatrix_fork_epoch {
-            // If the slot is post Bellatrix, do not sign messages when we cannot verify the
-            // optimistic status of the head block.
-            if slot.epoch(E::slots_per_epoch()) > bellatrix_fork_epoch {
-                warn!(
-                    log,
-                    "Refusing to sign sync committee messages for a head block with an unknown \
-                    optimistic status";
-                    "slot" => slot,
-                );
-                return Ok(());
-            }
-        }
+        };
 
         // Spawn one task to publish all of the sync committee signatures.
         let validator_duties = slot_duties.duties;