diff --git a/compose/docker-compose-fixturenet-optimism.yml b/compose/docker-compose-fixturenet-optimism.yml
index 08e9c61..2354419 100644
--- a/compose/docker-compose-fixturenet-optimism.yml
+++ b/compose/docker-compose-fixturenet-optimism.yml
@@ -8,13 +8,16 @@ services:
     hostname: fixturenet-optimism-contracts
     env_file:
       - ../config/fixturenet-optimism/l1-params.env
+      - ../config/fixturenet-optimism/l2-params.env
     environment:
-      CERC_SCRIPT_DEBUG: ${CERC_SCRIPT_DEBUG}
-      CERC_L1_CHAIN_ID: ${CERC_L1_CHAIN_ID}
-      CERC_L1_RPC: ${CERC_L1_RPC}
-      CERC_L1_ACCOUNTS_CSV_URL: ${CERC_L1_ACCOUNTS_CSV_URL}
-      CERC_L1_ADDRESS: ${CERC_L1_ADDRESS}
-      CERC_L1_PRIV_KEY: ${CERC_L1_PRIV_KEY}
+      - CERC_SCRIPT_DEBUG
+      - CERC_L1_CHAIN_ID
+      - CERC_L1_RPC
+      - CERC_L1_ACCOUNTS_CSV_URL
+      - CERC_L1_ADDRESS
+      - CERC_L1_PRIV_KEY
+      - CERC_L1_BLOCK_TIME
+      - CERC_L2_BLOCK_TIME
     volumes:
       - ../config/network/wait-for-it.sh:/wait-for-it.sh
       - ../config/fixturenet-optimism/optimism-contracts/deploy-contracts.sh:/deploy-contracts.sh
@@ -86,8 +89,9 @@ services:
     env_file:
       - ../config/fixturenet-optimism/l1-params.env
     environment:
-      CERC_SCRIPT_DEBUG: ${CERC_SCRIPT_DEBUG}
-      CERC_L1_RPC: ${CERC_L1_RPC}
+      - CERC_SCRIPT_DEBUG
+      - CERC_L1_RPC
+      - CERC_L1_BLOCK_TIME
     volumes:
       - ../config/fixturenet-optimism/run-op-node.sh:/run-op-node.sh
       - l1_deployment:/l1-deployment:ro
@@ -147,9 +151,10 @@ services:
     env_file:
       - ../config/fixturenet-optimism/l1-params.env
     environment:
-      CERC_SCRIPT_DEBUG: ${CERC_SCRIPT_DEBUG}
-      CERC_L1_RPC: ${CERC_L1_RPC}
-      CERC_L1_CHAIN_ID: ${CERC_L1_CHAIN_ID}
+      - CERC_SCRIPT_DEBUG
+      - CERC_L1_RPC
+      - CERC_L1_CHAIN_ID
+      - CERC_L1_BLOCK_TIME
     volumes:
       - ../config/network/wait-for-it.sh:/wait-for-it.sh
       - ../config/fixturenet-optimism/run-op-proposer.sh:/run-op-proposer.sh
diff --git a/config/fixturenet-optimism/l1-params.env b/config/fixturenet-optimism/l1-params.env
index 5353e62..b7c993f 100644
--- a/config/fixturenet-optimism/l1-params.env
+++ b/config/fixturenet-optimism/l1-params.env
@@ -6,6 +6,9 @@ DEFAULT_CERC_L1_RPC="http://fixturenet-eth-geth-1:8545"
 DEFAULT_CERC_L1_HOST="fixturenet-eth-geth-1"
 DEFAULT_CERC_L1_PORT=8545
 
+# Default block time to match L1 fixturenet config
+DEFAULT_CERC_L1_BLOCK_TIME=3
+
 # URL to get CSV with credentials for accounts on L1
 # that are used to send balance to Optimism Proxy contract
 # (enables them to do transactions on L2)
diff --git a/config/fixturenet-optimism/l2-params.env b/config/fixturenet-optimism/l2-params.env
new file mode 100644
index 0000000..a18c13c
--- /dev/null
+++ b/config/fixturenet-optimism/l2-params.env
@@ -0,0 +1,2 @@
+# Default L2 block time. Must be <= L1 block time.
+DEFAULT_CERC_L2_BLOCK_TIME=1
diff --git a/config/fixturenet-optimism/optimism-contracts/deploy-contracts.sh b/config/fixturenet-optimism/optimism-contracts/deploy-contracts.sh
index d8ab7be..9cec8e2 100755
--- a/config/fixturenet-optimism/optimism-contracts/deploy-contracts.sh
+++ b/config/fixturenet-optimism/optimism-contracts/deploy-contracts.sh
@@ -124,8 +124,8 @@ GS_SEQUENCER_ADDRESS=$SEQ \
 L1_RPC_URL=$CERC_L1_RPC \
 L1_CHAIN_ID=$CERC_L1_CHAIN_ID \
 L2_CHAIN_ID=42069 \
-L1_BLOCK_TIME=12 \
-L2_BLOCK_TIME=2 \
+L1_BLOCK_TIME=${CERC_L1_BLOCK_TIME:-$DEFAULT_CERC_L1_BLOCK_TIME} \
+L2_BLOCK_TIME=${CERC_L2_BLOCK_TIME:-$DEFAULT_CERC_L2_BLOCK_TIME} \
 $config_build_script
 
 echo "Writing deployment config."
diff --git a/config/fixturenet-optimism/run-op-node.sh b/config/fixturenet-optimism/run-op-node.sh
index 862de17..0b1e5e2 100755
--- a/config/fixturenet-optimism/run-op-node.sh
+++ b/config/fixturenet-optimism/run-op-node.sh
@@ -5,6 +5,7 @@ if [ -n "$CERC_SCRIPT_DEBUG" ]; then
 fi
 
 CERC_L1_RPC="${CERC_L1_RPC:-${DEFAULT_CERC_L1_RPC}}"
+CERC_L1_BLOCK_TIME="${CERC_L1_BLOCK_TIME:-$DEFAULT_CERC_L1_BLOCK_TIME}"
 
 # Start op-node
 rollup_config=/l2-config/rollup.json
@@ -27,4 +28,6 @@ exec op-node \
   --p2p.sequencer.key="${SEQ_KEY#0x}" \
   --l1=$CERC_L1_RPC \
   --l1.rpckind=$rpc_kind \
-  --l1.beacon=http://fixturenet-eth-lighthouse-1:8001
+  --l1.beacon=http://fixturenet-eth-lighthouse-1:8001 \
+  --l1.http-poll-interval="${CERC_L1_BLOCK_TIME}s" \
+  --l1.epoch-poll-interval="$((CERC_L1_BLOCK_TIME * 32))s"
diff --git a/config/fixturenet-optimism/run-op-proposer.sh b/config/fixturenet-optimism/run-op-proposer.sh
index 15ed1cb..28dc561 100755
--- a/config/fixturenet-optimism/run-op-proposer.sh
+++ b/config/fixturenet-optimism/run-op-proposer.sh
@@ -6,6 +6,7 @@ fi
 
 CERC_L1_RPC="${CERC_L1_RPC:-${DEFAULT_CERC_L1_RPC}}"
 CERC_L1_CHAIN_ID="${CERC_L1_CHAIN_ID:-${DEFAULT_CERC_L1_CHAIN_ID}}"
+CERC_L1_BLOCK_TIME="${CERC_L1_BLOCK_TIME:-${DEFAULT_CERC_L1_BLOCK_TIME}}"
 DEPLOYMENT_CONTEXT="$CERC_L1_CHAIN_ID"
 
 # Start op-proposer
@@ -14,7 +15,7 @@ PROPOSER_KEY=$(cat /l2-accounts/accounts.json | jq -r .ProposerKey)
 L2OO_ADDR=$(cat /l1-deployment/$DEPLOYMENT_CONTEXT-deploy.json | jq -r .L2OutputOracleProxy)
 
 exec op-proposer \
-  --poll-interval=12s \
+  --poll-interval="${CERC_L1_BLOCK_TIME}s" \
   --rpc.port=8560 \
   --rollup-rpc=$ROLLUP_RPC \
   --l2oo-address="${L2OO_ADDR#0x}" \