Merge pull request #4238 from filecoin-project/asr/changelog

Lotus version 0.9.0
2020-10-07 23:25:02 -04:00 · 2020-10-07 23:09:08 -04:00 · 2020-10-07 23:08:48 -04:00 · 2020-10-07 23:03:59 -04:00 · 2020-10-08 03:58:05 +02:00 · 2020-10-07 21:52:29 -04:00
273 changed files with 15077 additions and 5752 deletions
@@ -13,3 +13,4 @@
 ### Conformance testing.
 conformance/            @raulk
 extern/test-vectors     @raulk
+cmd/tvx                 @raulk
@@ -1,5 +1,221 @@
 # Lotus changelog

+# 0.9.0 / 2020-10-07
+
+This consensus-breaking release of Lotus upgrades the actors version to v2.0.0. This requires migrating actor state from v0 to v2. The changes that break consensus are:
+
+- Introducing v2 actors and its migration (https://github.com/filecoin-project/lotus/pull/3936)
+- Runtime's Receiver() should only return ID addresses  (https://github.com/filecoin-project/lotus/pull/3589)
+- Update miner eligibility checks for v2 actors (https://github.com/filecoin-project/lotus/pull/4188)
+- Add funds that have left FilReserve to circ supply (https://github.com/filecoin-project/lotus/pull/4160)
+- Set WinningPoStSectorSetLookback to finality post-v2 actors (https://github.com/filecoin-project/lotus/pull/4190)
+- fix: error when actor panics directly (https://github.com/filecoin-project/lotus/pull/3697)
+
+## Changes
+
+#### Dependencies
+
+- Update go-bitfield (https://github.com/filecoin-project/lotus/pull/4171)
+- update the AMT implementation (https://github.com/filecoin-project/lotus/pull/4194)
+- Update to actors v0.2.1 (https://github.com/filecoin-project/lotus/pull/4199)
+
+#### Core Lotus
+
+- Paych: fix voucher amount verification (https://github.com/filecoin-project/lotus/pull/3821)
+- Cap market provider messages (https://github.com/filecoin-project/lotus/pull/4141)
+- Run fork function after cron for null block safety (https://github.com/filecoin-project/lotus/pull/4114)
+- use bitswap sessions when fetching messages, and cancel them (https://github.com/filecoin-project/lotus/pull/4142)
+- relax pubsub IPColocationFactorThreshold to 5 (https://github.com/filecoin-project/lotus/pull/4183)
+- Support addresses with mainnet prefixes (https://github.com/filecoin-project/lotus/pull/4186)
+- fix: make message signer nonce generation transactional (https://github.com/filecoin-project/lotus/pull/4165)
+- build: Env var to keep test address output (https://github.com/filecoin-project/lotus/pull/4213)
+- make vm.EnableGasTracing public (https://github.com/filecoin-project/lotus/pull/4214)
+- introduce separate state-tree versions (https://github.com/filecoin-project/lotus/pull/4197)
+- reject explicit "calls" at the upgrade height (https://github.com/filecoin-project/lotus/pull/4231)
+- return an illegal actor error when we see an unsupported actor version (https://github.com/filecoin-project/lotus/pull/4232)
+- Set head should unmark blocks as valid (https://gist.github.com/travisperson/3c7cddd77a33979a519ccef4e6515f20)
+
+#### Mining
+
+- Increased ExpectedSealDuration and and WaitDealsDelay (https://github.com/filecoin-project/lotus/pull/3743)
+- Miner backup/restore commands (https://github.com/filecoin-project/lotus/pull/4133)
+- lotus-miner: add more help text to storage / attach (https://github.com/filecoin-project/lotus/pull/3961)
+- Reject deals that are > 7 days in the future in the BasicDealFilter (https://github.com/filecoin-project/lotus/pull/4173)
+- feat(miner): add miner deadline diffing logic (https://github.com/filecoin-project/lotus/pull/4178)
+
+#### UX
+
+- Improve the UX for replacing messages (https://github.com/filecoin-project/lotus/pull/4134)
+- Add verified flag to interactive deal creation (https://github.com/filecoin-project/lotus/pull/4145)
+- Add command to (slowly) prune lotus chain datastore (https://github.com/filecoin-project/lotus/pull/3876)
+- Some helpers for verifreg work (https://github.com/filecoin-project/lotus/pull/4124)
+- Always use default 720h for setask duration and hide the duration param option (https://github.com/filecoin-project/lotus/pull/4077)
+- Convert ID addresses to key addresses before checking wallet (https://github.com/filecoin-project/lotus/pull/4122)
+- add a command to view block space utilization (https://github.com/filecoin-project/lotus/pull/4176)
+- allow usage inspection on a chain segment (https://github.com/filecoin-project/lotus/pull/4177)
+- Add mpool stats for base fee (https://github.com/filecoin-project/lotus/pull/4170)
+- Add verified status to api.DealInfo (https://github.com/filecoin-project/lotus/pull/4153)
+- Add a CLI command to set a miner's owner address (https://github.com/filecoin-project/lotus/pull/4189)
+
+#### Tooling and validation
+
+- Lotus-pcr: add recover-miners command (https://github.com/filecoin-project/lotus/pull/3714)
+- MpoolPushUntrusted API for gateway (https://github.com/filecoin-project/lotus/pull/3915)
+- Test lotus-miner info all (https://github.com/filecoin-project/lotus/pull/4166)
+- chain export: Error with unfinished exports (https://github.com/filecoin-project/lotus/pull/4179)
+- add printf in TestWindowPost (https://github.com/filecoin-project/lotus/pull/4043)
+- add trace wdpost (https://github.com/filecoin-project/lotus/pull/4020)
+- Fix noncefix (https://github.com/filecoin-project/lotus/pull/4202)
+- Lotus-pcr: Limit the fee cap of messages we will process, refund gas fees for windowed post and storage deals (https://github.com/filecoin-project/lotus/pull/4198)
+- Fix pond (https://github.com/filecoin-project/lotus/pull/4203)
+- allow manual setting of noncefix fee cap (https://github.com/filecoin-project/lotus/pull/4205)
+- implement command to get execution traces of any message (https://github.com/filecoin-project/lotus/pull/4200)
+- conformance: minor driver refactors (https://github.com/filecoin-project/lotus/pull/4211) 
+- lotus-pcr: ignore all other messages (https://github.com/filecoin-project/lotus/pull/4218)
+- lotus-pcr: zero refund (https://github.com/filecoin-project/lotus/pull/4229)
+
+## Contributors
+
+The following contributors had 5 or more commits go into this release.
+We are grateful for every contribution!
+
+| Contributor        | Commits | Lines ±       |
+|--------------------|---------|---------------|
+| Stebalien          | 84       | +3425/-2287  |
+| magik6k            | 41       | +2121/-506   |
+| arajasek           | 39       | +2467/-424   |
+| Kubuxu             | 25       | +2344/-775   |
+| raulk              | 21       | +287/-196    |
+| whyrusleeping      | 13       | +727/-71     |
+| hsanjuan           | 13       | +5886/-7956  |
+| dirkmc             | 11       | +2634/-576   | 
+| travisperson       | 8        | +923/-202    |
+| ribasushi          | 6        | +188/-128    |
+| zgfzgf             | 5        | +21/-17      |
+
+# 0.8.1 / 2020-09-30
+
+This optional release of Lotus introduces a new version of markets which switches to CBOR-map encodings, and allows datastore migrations. The release also introduces several improvements to the mining process, a few performance optimizations, and a battery of UX additions and enhancements.
+
+## Changes 
+
+#### Dependencies
+
+- Markets 0.7.0 with updated data stores (https://github.com/filecoin-project/lotus/pull/4089)
+- Update ffi to code with blst fixes (https://github.com/filecoin-project/lotus/pull/3998)
+
+#### Core Lotus
+
+- Fix GetPower with no miner address (https://github.com/filecoin-project/lotus/pull/4049)
+- Refactor: Move nonce generation out of mpool (https://github.com/filecoin-project/lotus/pull/3970)
+
+#### Performance
+
+- Implement caching syscalls for import-bench (https://github.com/filecoin-project/lotus/pull/3888)
+- Fetch tipset blocks in parallel (https://github.com/filecoin-project/lotus/pull/4074)
+- Optimize Tipset equals() (https://github.com/filecoin-project/lotus/pull/4056)
+- Make state transition in validation async (https://github.com/filecoin-project/lotus/pull/3868)
+
+#### Mining
+
+- Add trace window post (https://github.com/filecoin-project/lotus/pull/4020)
+- Use abstract types for Dont recompute post on revert (https://github.com/filecoin-project/lotus/pull/4022)
+- Fix injectNulls logic in test miner (https://github.com/filecoin-project/lotus/pull/4058)
+- Fix potential panic in FinalizeSector (https://github.com/filecoin-project/lotus/pull/4092)
+- Don't recompute post on revert (https://github.com/filecoin-project/lotus/pull/3924)
+- Fix some failed precommit handling (https://github.com/filecoin-project/lotus/pull/3445)
+- Add --no-swap flag for worker (https://github.com/filecoin-project/lotus/pull/4107)
+- Allow some single-thread tasks to run in parallel with PC2/C2 (https://github.com/filecoin-project/lotus/pull/4116)
+
+#### UX
+
+- Add an envvar to set address network version (https://github.com/filecoin-project/lotus/pull/4028)
+- Add logging to chain export (https://github.com/filecoin-project/lotus/pull/4030)
+- Add JSON output to state compute (https://github.com/filecoin-project/lotus/pull/4038)
+- Wallet list CLI: Print balances/nonces (https://github.com/filecoin-project/lotus/pull/4088)
+- Added an option to show or not show sector info for `lotus-miner info` (https://github.com/filecoin-project/lotus/pull/4003)
+- Add a command to import an ipld object into the chainstore (https://github.com/filecoin-project/lotus/pull/3434)
+- Improve the lotus-shed dealtracker (https://github.com/filecoin-project/lotus/pull/4051)
+- Docs review and re-organization (https://github.com/filecoin-project/lotus/pull/3431)
+- Fix wallet list (https://github.com/filecoin-project/lotus/pull/4104)
+- Add an endpoint to validate whether a string is a well-formed address (https://github.com/filecoin-project/lotus/pull/4106)
+- Add an option to set config path (https://github.com/filecoin-project/lotus/pull/4103)
+- Add printf in TestWindowPost (https://github.com/filecoin-project/lotus/pull/4043)
+- Improve miner sectors list UX (https://github.com/filecoin-project/lotus/pull/4108)
+
+#### Tooling
+
+- Move policy change to seal bench (https://github.com/filecoin-project/lotus/pull/4032)
+- Add back network power to stats (https://github.com/filecoin-project/lotus/pull/4050)
+- Conformance: Record and feed circulating supply (https://github.com/filecoin-project/lotus/pull/4078)
+- Snapshot import progress bar, add HTTP support (https://github.com/filecoin-project/lotus/pull/4070)
+- Add lotus shed util to validate a tipset (https://github.com/filecoin-project/lotus/pull/4065)
+- tvx: a test vector extraction and execution tool (https://github.com/filecoin-project/lotus/pull/4064)
+
+#### Bootstrap
+
+- Add new bootstrappers (https://github.com/filecoin-project/lotus/pull/4007)
+- Add Glif node to bootstrap peers (https://github.com/filecoin-project/lotus/pull/4004)
+- Add one more node located in China (https://github.com/filecoin-project/lotus/pull/4041)
+- Add ipfsmain bootstrapper (https://github.com/filecoin-project/lotus/pull/4067)
+
+# 0.8.0 / 2020-09-26
+
+This consensus-breaking release of Lotus introduces an upgrade to the network. The changes that break consensus are:
+
+- Upgrading to specs-actors v0.9.11, which reduces WindowPoSt faults per [FIP 0002](https://github.com/filecoin-project/FIPs/blob/master/FIPS/fip-0002.md) to reduce cost for honest miners with occasional faults (see https://github.com/filecoin-project/specs-actors/pull/1181)
+- Revisions to some cryptoeconomics and network params
+
+This release also updates go-fil-markets to fix an incompatibility issue between v0.7.2 and earlier versions.
+
+## Changes 
+
+#### Dependencies
+
+- Update spec actors to 0.9.11 (https://github.com/filecoin-project/lotus/pull/4039)
+- Update markets to 0.6.3 (https://github.com/filecoin-project/lotus/pull/4013)
+
+#### Core Lotus
+
+- Network upgrade (https://github.com/filecoin-project/lotus/pull/4039)
+- Fix AddSupportedProofTypes (https://github.com/filecoin-project/lotus/pull/4033)
+- Return an error when we fail to find a sector when checking sector expiration (https://github.com/filecoin-project/lotus/pull/4026)
+- Batch blockstore copies after block validation (https://github.com/filecoin-project/lotus/pull/3980)
+- Remove a misleading miner actor abstraction (https://github.com/filecoin-project/lotus/pull/3977)
+- Fix out-of-bounds when loading all sector infos (https://github.com/filecoin-project/lotus/pull/3976)
+- Fix break condition in the miner (https://github.com/filecoin-project/lotus/pull/3953)
+
+#### UX
+
+- Correct helptext around miners setting ask (https://github.com/filecoin-project/lotus/pull/4009)
+- Make sync wait nicer (https://github.com/filecoin-project/lotus/pull/3991)
+
+#### Tooling and validation
+
+- Small adjustments following network upgradability changes (https://github.com/filecoin-project/lotus/pull/3996)
+- Add some more big pictures stats to stateroot stat (https://github.com/filecoin-project/lotus/pull/3995)
+- Add some actors policy setters for testing (https://github.com/filecoin-project/lotus/pull/3975)
+
+## Contributors
+
+The following contributors had 5 or more commits go into this release.
+We are grateful for every contribution!
+
+| Contributor        | Commits | Lines ±       |
+|--------------------|---------|---------------|
+| arajasek           | 66       | +3140/-1261  |
+| Stebalien          | 64       | +3797/-3434  |
+| magik6k            | 48       | +1892/-976   |
+| raulk              | 40       | +2412/-1549  |
+| vyzo               | 22       | +287/-196    |
+| alanshaw           | 15       | +761/-146    |
+| whyrusleeping      | 15       | +736/-52     |
+| hannahhoward       | 14       | +1237/-837   | 
+| anton              | 6        | +32/-8       |
+| travisperson       | 5        | +502/-6      |
+| Frank              | 5        | +78/-39      |
+| Jennifer           | 5        | +148/-41     |
+
 # 0.7.2 / 2020-09-23

 This optional release of Lotus introduces a major refactor around how a Lotus node interacts with code from the specs-actors repo. We now use interfaces to read the state of actors, which is required to be able to reason about different versions of actors code at the same time.
@@ -1,5 +1,5 @@
 <p align="center">
-  <a href="https://lotu.sh/" title="Lotus Docs">
+  <a href="https://docs.filecoin.io/" title="Filecoin Docs">
    <img src="documentation/images/lotus_logo_h.png" alt="Project Lotus Logo" width="244" />
  </a>
 </p>
@@ -18,7 +18,7 @@ Lotus is an implementation of the Filecoin Distributed Storage Network. For more

 ## Building & Documentation

-For instructions on how to build lotus from source, please visit [Lotus build and setup instruction](https://docs.filecoin.io/get-started/lotus/installation/#minimal-requirements) or read the source [here](https://github.com/filecoin-project/lotus/tree/master/documentation).
+For instructions on how to build, install and setup lotus, please visit [https://docs.filecoin.io/get-started/lotus](https://docs.filecoin.io/get-started/lotus/).

 ## Reporting a Vulnerability

@@ -176,6 +176,9 @@ type FullNode interface {
 	// the reason.
 	SyncCheckBad(ctx context.Context, bcid cid.Cid) (string, error)

+	// SyncValidateTipset indicates whether the provided tipset is valid or not
+	SyncValidateTipset(ctx context.Context, tsk types.TipSetKey) (bool, error)
+
 	// MethodGroup: Mpool
 	// The Mpool methods are for interacting with the message pool. The message pool
 	// manages all incoming and outgoing 'messages' going over the network.
@@ -189,6 +192,9 @@ type FullNode interface {
 	// MpoolPush pushes a signed message to mempool.
 	MpoolPush(context.Context, *types.SignedMessage) (cid.Cid, error)

+	// MpoolPushUntrusted pushes a signed message to mempool from untrusted sources.
+	MpoolPushUntrusted(context.Context, *types.SignedMessage) (cid.Cid, error)
+
 	// MpoolPushMessage atomically assigns a nonce, signs, and pushes a message
 	// to mempool.
 	// maxFee is only used when GasFeeCap/GasPremium fields aren't specified
@@ -244,6 +250,8 @@ type FullNode interface {
 	WalletImport(context.Context, *types.KeyInfo) (address.Address, error)
 	// WalletDelete deletes an address from the wallet.
 	WalletDelete(context.Context, address.Address) error
+	// WalletValidateAddress validates whether a given string can be decoded as a well-formed address
+	WalletValidateAddress(context.Context, string) (address.Address, error)

 	// Other

@@ -275,7 +283,7 @@ type FullNode interface {
 	// of status updates.
 	ClientRetrieveWithEvents(ctx context.Context, order RetrievalOrder, ref *FileRef) (<-chan marketevents.RetrievalEvent, error)
 	// ClientQueryAsk returns a signed StorageAsk from the specified miner.
-	ClientQueryAsk(ctx context.Context, p peer.ID, miner address.Address) (*storagemarket.SignedStorageAsk, error)
+	ClientQueryAsk(ctx context.Context, p peer.ID, miner address.Address) (*storagemarket.StorageAsk, error)
 	// ClientCalcCommP calculates the CommP for a specified file
 	ClientCalcCommP(ctx context.Context, inpath string) (*CommPRet, error)
 	// ClientGenCar generates a CAR file for the specified file.
@@ -385,10 +393,16 @@ type FullNode interface {
 	// StateCompute is a flexible command that applies the given messages on the given tipset.
 	// The messages are run as though the VM were at the provided height.
 	StateCompute(context.Context, abi.ChainEpoch, []*types.Message, types.TipSetKey) (*ComputeStateOutput, error)
+	// StateVerifierStatus returns the data cap for the given address.
+	// Returns nil if there is no entry in the data cap table for the
+	// address.
+	StateVerifierStatus(ctx context.Context, addr address.Address, tsk types.TipSetKey) (*abi.StoragePower, error)
 	// StateVerifiedClientStatus returns the data cap for the given address.
 	// Returns nil if there is no entry in the data cap table for the
 	// address.
 	StateVerifiedClientStatus(ctx context.Context, addr address.Address, tsk types.TipSetKey) (*abi.StoragePower, error)
+	// StateVerifiedClientStatus returns the address of the Verified Registry's root key
+	StateVerifiedRegistryRootKey(ctx context.Context, tsk types.TipSetKey) (address.Address, error)
 	// StateDealProviderCollateralBounds returns the min and max collateral a storage provider
 	// can issue. It takes the deal size and verified status as parameters.
 	StateDealProviderCollateralBounds(context.Context, abi.PaddedPieceSize, bool, types.TipSetKey) (DealCollateralBounds, error)
@@ -470,6 +484,12 @@ type FullNode interface {
 	PaychVoucherAdd(context.Context, address.Address, *paych.SignedVoucher, []byte, types.BigInt) (types.BigInt, error)
 	PaychVoucherList(context.Context, address.Address) ([]*paych.SignedVoucher, error)
 	PaychVoucherSubmit(context.Context, address.Address, *paych.SignedVoucher, []byte, []byte) (cid.Cid, error)
+
+	// CreateBackup creates node backup onder the specified file name. The
+	// method requires that the lotus daemon is running with the
+	// LOTUS_BACKUP_BASE_PATH environment variable set to some path, and that
+	// the path specified when calling CreateBackup is within the base path
+	CreateBackup(ctx context.Context, fpath string) error
 }

 type FileRef struct {
@@ -516,6 +536,7 @@ type DealInfo struct {
 	DealID abi.DealID

 	CreationTime time.Time
+	Verified     bool
 }

 type MsgLookup struct {
@@ -725,6 +746,8 @@ type ActiveSync struct {

 type SyncState struct {
 	ActiveSyncs []ActiveSync
+
+	VMApplied uint64
 }

 type SyncStateStage int
@@ -789,14 +812,14 @@ type CirculatingSupply struct {
 }

 type MiningBaseInfo struct {
-	MinerPower      types.BigInt
-	NetworkPower    types.BigInt
-	Sectors         []builtin.SectorInfo
-	WorkerKey       address.Address
-	SectorSize      abi.SectorSize
-	PrevBeaconEntry types.BeaconEntry
-	BeaconEntries   []types.BeaconEntry
-	HasMinPower     bool
+	MinerPower        types.BigInt
+	NetworkPower      types.BigInt
+	Sectors           []builtin.SectorInfo
+	WorkerKey         address.Address
+	SectorSize        abi.SectorSize
+	PrevBeaconEntry   types.BeaconEntry
+	BeaconEntries     []types.BeaconEntry
+	EligibleForMining bool
 }

 type BlockTemplate struct {
@@ -101,6 +101,12 @@ type StorageMiner interface {
 	PiecesListCidInfos(ctx context.Context) ([]cid.Cid, error)
 	PiecesGetPieceInfo(ctx context.Context, pieceCid cid.Cid) (*piecestore.PieceInfo, error)
 	PiecesGetCIDInfo(ctx context.Context, payloadCid cid.Cid) (*piecestore.CIDInfo, error)
+
+	// CreateBackup creates node backup onder the specified file name. The
+	// method requires that the lotus-miner is running with the
+	// LOTUS_BACKUP_BASE_PATH environment variable set to some path, and that
+	// the path specified when calling CreateBackup is within the base path
+	CreateBackup(ctx context.Context, fpath string) error
 }

 type SealRes struct {
@@ -112,6 +112,7 @@ type FullNodeStruct struct {
 		SyncMarkBad        func(ctx context.Context, bcid cid.Cid) error                `perm:"admin"`
 		SyncUnmarkBad      func(ctx context.Context, bcid cid.Cid) error                `perm:"admin"`
 		SyncCheckBad       func(ctx context.Context, bcid cid.Cid) (string, error)      `perm:"read"`
+		SyncValidateTipset func(ctx context.Context, tsk types.TipSetKey) (bool, error) `perm:"read"`

 		MpoolGetConfig func(context.Context) (*types.MpoolConfig, error) `perm:"read"`
 		MpoolSetConfig func(context.Context, *types.MpoolConfig) error   `perm:"write"`
@@ -121,7 +122,9 @@ type FullNodeStruct struct {
 		MpoolPending func(context.Context, types.TipSetKey) ([]*types.SignedMessage, error) `perm:"read"`
 		MpoolClear   func(context.Context, bool) error                                      `perm:"write"`

-		MpoolPush        func(context.Context, *types.SignedMessage) (cid.Cid, error)                              `perm:"write"`
+		MpoolPush          func(context.Context, *types.SignedMessage) (cid.Cid, error) `perm:"write"`
+		MpoolPushUntrusted func(context.Context, *types.SignedMessage) (cid.Cid, error) `perm:"write"`
+
 		MpoolPushMessage func(context.Context, *types.Message, *api.MessageSendSpec) (*types.SignedMessage, error) `perm:"sign"`
 		MpoolGetNonce    func(context.Context, address.Address) (uint64, error)                                    `perm:"read"`
 		MpoolSub         func(context.Context) (<-chan api.MpoolUpdate, error)                                     `perm:"read"`
@@ -129,18 +132,19 @@ type FullNodeStruct struct {
 		MinerGetBaseInfo func(context.Context, address.Address, abi.ChainEpoch, types.TipSetKey) (*api.MiningBaseInfo, error) `perm:"read"`
 		MinerCreateBlock func(context.Context, *api.BlockTemplate) (*types.BlockMsg, error)                                   `perm:"write"`

-		WalletNew            func(context.Context, crypto.SigType) (address.Address, error)                       `perm:"write"`
-		WalletHas            func(context.Context, address.Address) (bool, error)                                 `perm:"write"`
-		WalletList           func(context.Context) ([]address.Address, error)                                     `perm:"write"`
-		WalletBalance        func(context.Context, address.Address) (types.BigInt, error)                         `perm:"read"`
-		WalletSign           func(context.Context, address.Address, []byte) (*crypto.Signature, error)            `perm:"sign"`
-		WalletSignMessage    func(context.Context, address.Address, *types.Message) (*types.SignedMessage, error) `perm:"sign"`
-		WalletVerify         func(context.Context, address.Address, []byte, *crypto.Signature) (bool, error)      `perm:"read"`
-		WalletDefaultAddress func(context.Context) (address.Address, error)                                       `perm:"write"`
-		WalletSetDefault     func(context.Context, address.Address) error                                         `perm:"admin"`
-		WalletExport         func(context.Context, address.Address) (*types.KeyInfo, error)                       `perm:"admin"`
-		WalletImport         func(context.Context, *types.KeyInfo) (address.Address, error)                       `perm:"admin"`
-		WalletDelete         func(context.Context, address.Address) error                                         `perm:"write"`
+		WalletNew             func(context.Context, crypto.SigType) (address.Address, error)                       `perm:"write"`
+		WalletHas             func(context.Context, address.Address) (bool, error)                                 `perm:"write"`
+		WalletList            func(context.Context) ([]address.Address, error)                                     `perm:"write"`
+		WalletBalance         func(context.Context, address.Address) (types.BigInt, error)                         `perm:"read"`
+		WalletSign            func(context.Context, address.Address, []byte) (*crypto.Signature, error)            `perm:"sign"`
+		WalletSignMessage     func(context.Context, address.Address, *types.Message) (*types.SignedMessage, error) `perm:"sign"`
+		WalletVerify          func(context.Context, address.Address, []byte, *crypto.Signature) (bool, error)      `perm:"read"`
+		WalletDefaultAddress  func(context.Context) (address.Address, error)                                       `perm:"write"`
+		WalletSetDefault      func(context.Context, address.Address) error                                         `perm:"admin"`
+		WalletExport          func(context.Context, address.Address) (*types.KeyInfo, error)                       `perm:"admin"`
+		WalletImport          func(context.Context, *types.KeyInfo) (address.Address, error)                       `perm:"admin"`
+		WalletDelete          func(context.Context, address.Address) error                                         `perm:"write"`
+		WalletValidateAddress func(context.Context, string) (address.Address, error)                               `perm:"read"`

 		ClientImport                              func(ctx context.Context, ref api.FileRef) (*api.ImportRes, error)                                                `perm:"admin"`
 		ClientListImports                         func(ctx context.Context) ([]api.Import, error)                                                                   `perm:"write"`
@@ -154,7 +158,7 @@ type FullNodeStruct struct {
 		ClientGetDealUpdates                      func(ctx context.Context) (<-chan api.DealInfo, error)                                                            `perm:"read"`
 		ClientRetrieve                            func(ctx context.Context, order api.RetrievalOrder, ref *api.FileRef) error                                       `perm:"admin"`
 		ClientRetrieveWithEvents                  func(ctx context.Context, order api.RetrievalOrder, ref *api.FileRef) (<-chan marketevents.RetrievalEvent, error) `perm:"admin"`
-		ClientQueryAsk                            func(ctx context.Context, p peer.ID, miner address.Address) (*storagemarket.SignedStorageAsk, error)              `perm:"read"`
+		ClientQueryAsk                            func(ctx context.Context, p peer.ID, miner address.Address) (*storagemarket.StorageAsk, error)                    `perm:"read"`
 		ClientCalcCommP                           func(ctx context.Context, inpath string) (*api.CommPRet, error)                                                   `perm:"read"`
 		ClientGenCar                              func(ctx context.Context, ref api.FileRef, outpath string) error                                                  `perm:"write"`
 		ClientDealSize                            func(ctx context.Context, root cid.Cid) (api.DataSize, error)                                                     `perm:"read"`
@@ -200,7 +204,9 @@ type FullNodeStruct struct {
 		StateMinerSectorCount              func(context.Context, address.Address, types.TipSetKey) (api.MinerSectors, error)                                   `perm:"read"`
 		StateListMessages                  func(ctx context.Context, match *types.Message, tsk types.TipSetKey, toht abi.ChainEpoch) ([]cid.Cid, error)        `perm:"read"`
 		StateCompute                       func(context.Context, abi.ChainEpoch, []*types.Message, types.TipSetKey) (*api.ComputeStateOutput, error)           `perm:"read"`
+		StateVerifierStatus                func(context.Context, address.Address, types.TipSetKey) (*abi.StoragePower, error)                                  `perm:"read"`
 		StateVerifiedClientStatus          func(context.Context, address.Address, types.TipSetKey) (*abi.StoragePower, error)                                  `perm:"read"`
+		StateVerifiedRegistryRootKey       func(ctx context.Context, tsk types.TipSetKey) (address.Address, error)                                             `perm:"read"`
 		StateDealProviderCollateralBounds  func(context.Context, abi.PaddedPieceSize, bool, types.TipSetKey) (api.DealCollateralBounds, error)                 `perm:"read"`
 		StateCirculatingSupply             func(context.Context, types.TipSetKey) (api.CirculatingSupply, error)                                               `perm:"read"`
 		StateNetworkVersion                func(context.Context, types.TipSetKey) (stnetwork.Version, error)                                                   `perm:"read"`
@@ -237,6 +243,8 @@ type FullNodeStruct struct {
 		PaychVoucherCreate          func(context.Context, address.Address, big.Int, uint64) (*api.VoucherCreateResult, error)                 `perm:"sign"`
 		PaychVoucherList            func(context.Context, address.Address) ([]*paych.SignedVoucher, error)                                    `perm:"write"`
 		PaychVoucherSubmit          func(context.Context, address.Address, *paych.SignedVoucher, []byte, []byte) (cid.Cid, error)             `perm:"sign"`
+
+		CreateBackup func(ctx context.Context, fpath string) error `perm:"admin"`
 	}
 }

@@ -317,6 +325,8 @@ type StorageMinerStruct struct {
 		PiecesListCidInfos func(ctx context.Context) ([]cid.Cid, error)                               `perm:"read"`
 		PiecesGetPieceInfo func(ctx context.Context, pieceCid cid.Cid) (*piecestore.PieceInfo, error) `perm:"read"`
 		PiecesGetCIDInfo   func(ctx context.Context, payloadCid cid.Cid) (*piecestore.CIDInfo, error) `perm:"read"`
+
+		CreateBackup func(ctx context.Context, fpath string) error `perm:"admin"`
 	}
 }

@@ -484,7 +494,7 @@ func (c *FullNodeStruct) ClientRetrieveWithEvents(ctx context.Context, order api
 	return c.Internal.ClientRetrieveWithEvents(ctx, order, ref)
 }

-func (c *FullNodeStruct) ClientQueryAsk(ctx context.Context, p peer.ID, miner address.Address) (*storagemarket.SignedStorageAsk, error) {
+func (c *FullNodeStruct) ClientQueryAsk(ctx context.Context, p peer.ID, miner address.Address) (*storagemarket.StorageAsk, error) {
 	return c.Internal.ClientQueryAsk(ctx, p, miner)
 }
 func (c *FullNodeStruct) ClientCalcCommP(ctx context.Context, inpath string) (*api.CommPRet, error) {
@@ -551,6 +561,10 @@ func (c *FullNodeStruct) MpoolPush(ctx context.Context, smsg *types.SignedMessag
 	return c.Internal.MpoolPush(ctx, smsg)
 }

+func (c *FullNodeStruct) MpoolPushUntrusted(ctx context.Context, smsg *types.SignedMessage) (cid.Cid, error) {
+	return c.Internal.MpoolPushUntrusted(ctx, smsg)
+}
+
 func (c *FullNodeStruct) MpoolPushMessage(ctx context.Context, msg *types.Message, spec *api.MessageSendSpec) (*types.SignedMessage, error) {
 	return c.Internal.MpoolPushMessage(ctx, msg, spec)
 }
@@ -631,6 +645,10 @@ func (c *FullNodeStruct) WalletDelete(ctx context.Context, addr address.Address)
 	return c.Internal.WalletDelete(ctx, addr)
 }

+func (c *FullNodeStruct) WalletValidateAddress(ctx context.Context, str string) (address.Address, error) {
+	return c.Internal.WalletValidateAddress(ctx, str)
+}
+
 func (c *FullNodeStruct) MpoolGetNonce(ctx context.Context, addr address.Address) (uint64, error) {
 	return c.Internal.MpoolGetNonce(ctx, addr)
 }
@@ -735,6 +753,10 @@ func (c *FullNodeStruct) SyncCheckBad(ctx context.Context, bcid cid.Cid) (string
 	return c.Internal.SyncCheckBad(ctx, bcid)
 }

+func (c *FullNodeStruct) SyncValidateTipset(ctx context.Context, tsk types.TipSetKey) (bool, error) {
+	return c.Internal.SyncValidateTipset(ctx, tsk)
+}
+
 func (c *FullNodeStruct) StateNetworkName(ctx context.Context) (dtypes.NetworkName, error) {
 	return c.Internal.StateNetworkName(ctx)
 }
@@ -883,10 +905,18 @@ func (c *FullNodeStruct) StateCompute(ctx context.Context, height abi.ChainEpoch
 	return c.Internal.StateCompute(ctx, height, msgs, tsk)
 }

+func (c *FullNodeStruct) StateVerifierStatus(ctx context.Context, addr address.Address, tsk types.TipSetKey) (*abi.StoragePower, error) {
+	return c.Internal.StateVerifierStatus(ctx, addr, tsk)
+}
+
 func (c *FullNodeStruct) StateVerifiedClientStatus(ctx context.Context, addr address.Address, tsk types.TipSetKey) (*abi.StoragePower, error) {
 	return c.Internal.StateVerifiedClientStatus(ctx, addr, tsk)
 }

+func (c *FullNodeStruct) StateVerifiedRegistryRootKey(ctx context.Context, tsk types.TipSetKey) (address.Address, error) {
+	return c.Internal.StateVerifiedRegistryRootKey(ctx, tsk)
+}
+
 func (c *FullNodeStruct) StateDealProviderCollateralBounds(ctx context.Context, size abi.PaddedPieceSize, verified bool, tsk types.TipSetKey) (api.DealCollateralBounds, error) {
 	return c.Internal.StateDealProviderCollateralBounds(ctx, size, verified, tsk)
 }
@@ -1015,6 +1045,10 @@ func (c *FullNodeStruct) PaychVoucherSubmit(ctx context.Context, ch address.Addr
 	return c.Internal.PaychVoucherSubmit(ctx, ch, sv, secret, proof)
 }

+func (c *FullNodeStruct) CreateBackup(ctx context.Context, fpath string) error {
+	return c.Internal.CreateBackup(ctx, fpath)
+}
+
 // StorageMinerStruct

 func (c *StorageMinerStruct) ActorAddress(ctx context.Context) (address.Address, error) {
@@ -1255,6 +1289,10 @@ func (c *StorageMinerStruct) PiecesGetCIDInfo(ctx context.Context, payloadCid ci
 	return c.Internal.PiecesGetCIDInfo(ctx, payloadCid)
 }

+func (c *StorageMinerStruct) CreateBackup(ctx context.Context, fpath string) error {
+	return c.Internal.CreateBackup(ctx, fpath)
+}
+
 // WorkerStruct

 func (w *WorkerStruct) Version(ctx context.Context) (build.Version, error) {
@@ -12,15 +12,36 @@ import (

 	"github.com/filecoin-project/go-state-types/abi"

+	"github.com/filecoin-project/lotus/build"
+	"github.com/filecoin-project/lotus/chain/stmgr"
 	"github.com/filecoin-project/lotus/chain/types"
+	"github.com/filecoin-project/lotus/node"
 	"github.com/filecoin-project/lotus/node/impl"
 )

 func TestCCUpgrade(t *testing.T, b APIBuilder, blocktime time.Duration) {
 	_ = os.Setenv("BELLMAN_NO_GPU", "1")

+	for _, height := range []abi.ChainEpoch{
+		1,    // before
+		162,  // while sealing
+		520,  // after upgrade deal
+		5000, // after
+	} {
+		height := height // make linters happy by copying
+		t.Run(fmt.Sprintf("upgrade-%d", height), func(t *testing.T) {
+			testCCUpgrade(t, b, blocktime, height)
+		})
+	}
+}
+
+func testCCUpgrade(t *testing.T, b APIBuilder, blocktime time.Duration, upgradeHeight abi.ChainEpoch) {
 	ctx := context.Background()
-	n, sn := b(t, 1, OneMiner)
+	n, sn := b(t, 1, OneMiner, node.Override(new(stmgr.UpgradeSchedule), stmgr.UpgradeSchedule{{
+		Network:   build.ActorUpgradeNetworkVersion,
+		Height:    upgradeHeight,
+		Migration: stmgr.UpgradeActorsV2,
+	}}))
 	client := n[0].FullNode.(*impl.FullNodeAPI)
 	miner := sn[0]

@@ -94,6 +115,22 @@ func TestCCUpgrade(t *testing.T, b APIBuilder, blocktime time.Duration) {
 		require.Less(t, 50000, int(exp.OnTime))
 	}

+	dlInfo, err := client.StateMinerProvingDeadline(ctx, maddr, types.EmptyTSK)
+	require.NoError(t, err)
+
+	// Sector should expire.
+	for {
+		// Wait for the sector to expire.
+		status, err := miner.SectorsStatus(ctx, CC, true)
+		require.NoError(t, err)
+		if status.OnTime == 0 && status.Early == 0 {
+			break
+		}
+		t.Log("waiting for sector to expire")
+		// wait one deadline per loop.
+		time.Sleep(time.Duration(dlInfo.WPoStChallengeWindow) * blocktime)
+	}
+
 	fmt.Println("shutting down mining")
 	atomic.AddInt64(&mine, -1)
 	<-done
@@ -402,9 +402,12 @@ func testRetrieval(t *testing.T, ctx context.Context, client *impl.FullNodeAPI,
 		IsCAR: carExport,
 	}
 	updates, err := client.ClientRetrieveWithEvents(ctx, offers[0].Order(caddr), ref)
+	if err != nil {
+		t.Fatal(err)
+	}
 	for update := range updates {
 		if update.Err != "" {
-			t.Fatalf("%v", err)
+			t.Fatalf("retrieval failed: %s", update.Err)
 		}
 	}

@@ -8,17 +8,21 @@ import (
 	"testing"
 	"time"

-	"github.com/filecoin-project/specs-actors/actors/builtin"
+	builtin0 "github.com/filecoin-project/specs-actors/actors/builtin"
+	paych0 "github.com/filecoin-project/specs-actors/actors/builtin/paych"

 	"github.com/filecoin-project/go-state-types/abi"
 	"github.com/filecoin-project/go-state-types/big"
-	"github.com/filecoin-project/specs-actors/actors/builtin/paych"
 	"github.com/ipfs/go-cid"

 	"github.com/filecoin-project/go-address"
+	cbor "github.com/ipfs/go-ipld-cbor"

 	"github.com/filecoin-project/lotus/api"
+	"github.com/filecoin-project/lotus/api/apibstore"
 	"github.com/filecoin-project/lotus/build"
+	"github.com/filecoin-project/lotus/chain/actors/adt"
+	"github.com/filecoin-project/lotus/chain/actors/builtin/paych"
 	"github.com/filecoin-project/lotus/chain/events"
 	"github.com/filecoin-project/lotus/chain/events/state"
 	"github.com/filecoin-project/lotus/chain/types"
@@ -67,7 +71,7 @@ func TestPaymentChannels(t *testing.T, b APIBuilder, blocktime time.Duration) {
 		t.Fatal(err)
 	}

-	channelAmt := int64(100000)
+	channelAmt := int64(7000)
 	channelInfo, err := paymentCreator.PaychGet(ctx, createrAddr, receiverAddr, abi.NewTokenAmount(channelAmt))
 	if err != nil {
 		t.Fatal(err)
@@ -133,17 +137,26 @@ func TestPaymentChannels(t *testing.T, b APIBuilder, blocktime time.Duration) {
 		t.Fatal("Unable to settle payment channel")
 	}

+	creatorStore := adt.WrapStore(ctx, cbor.NewCborStore(apibstore.NewAPIBlockstore(paymentCreator)))
+
 	// wait for the receiver to submit their vouchers
 	ev := events.NewEvents(ctx, paymentCreator)
 	preds := state.NewStatePredicates(paymentCreator)
 	finished := make(chan struct{})
 	err = ev.StateChanged(func(ts *types.TipSet) (done bool, more bool, err error) {
-		act, err := paymentCreator.StateReadState(ctx, channel, ts.Key())
+		act, err := paymentCreator.StateGetActor(ctx, channel, ts.Key())
 		if err != nil {
 			return false, false, err
 		}
-		state := act.State.(paych.State)
-		if state.ToSend.GreaterThanEqual(abi.NewTokenAmount(6000)) {
+		state, err := paych.Load(creatorStore, act)
+		if err != nil {
+			return false, false, err
+		}
+		toSend, err := state.ToSend()
+		if err != nil {
+			return false, false, err
+		}
+		if toSend.GreaterThanEqual(abi.NewTokenAmount(6000)) {
 			return true, false, nil
 		}
 		return false, true, nil
@@ -156,7 +169,7 @@ func TestPaymentChannels(t *testing.T, b APIBuilder, blocktime time.Duration) {
 		return true, nil
 	}, func(ctx context.Context, ts *types.TipSet) error {
 		return nil
-	}, int(build.MessageConfidence)+1, build.SealRandomnessLookbackLimit, func(oldTs, newTs *types.TipSet) (bool, events.StateChange, error) {
+	}, int(build.MessageConfidence)+1, build.Finality, func(oldTs, newTs *types.TipSet) (bool, events.StateChange, error) {
 		return preds.OnPaymentChannelActorChanged(channel, preds.OnToSendAmountChanges())(ctx, oldTs.Key(), newTs.Key())
 	})
 	if err != nil {
@@ -169,8 +182,53 @@ func TestPaymentChannels(t *testing.T, b APIBuilder, blocktime time.Duration) {
 		t.Fatal("Timed out waiting for receiver to submit vouchers")
 	}

+	// Create a new voucher now that some vouchers have already been submitted
+	vouchRes, err := paymentCreator.PaychVoucherCreate(ctx, channel, abi.NewTokenAmount(1000), 3)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if vouchRes.Voucher == nil {
+		t.Fatal(fmt.Errorf("Not enough funds to create voucher: missing %d", vouchRes.Shortfall))
+	}
+	vdelta, err := paymentReceiver.PaychVoucherAdd(ctx, channel, vouchRes.Voucher, nil, abi.NewTokenAmount(1000))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !vdelta.Equals(abi.NewTokenAmount(1000)) {
+		t.Fatal("voucher didn't have the right amount")
+	}
+
+	// Create a new voucher whose value would exceed the channel balance
+	excessAmt := abi.NewTokenAmount(1000)
+	vouchRes, err = paymentCreator.PaychVoucherCreate(ctx, channel, excessAmt, 4)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if vouchRes.Voucher != nil {
+		t.Fatal("Expected not to be able to create voucher whose value would exceed channel balance")
+	}
+	if !vouchRes.Shortfall.Equals(excessAmt) {
+		t.Fatal(fmt.Errorf("Expected voucher shortfall of %d, got %d", excessAmt, vouchRes.Shortfall))
+	}
+
+	// Add a voucher whose value would exceed the channel balance
+	vouch := &paych.SignedVoucher{ChannelAddr: channel, Amount: excessAmt, Lane: 4, Nonce: 1}
+	vb, err := vouch.SigningBytes()
+	if err != nil {
+		t.Fatal(err)
+	}
+	sig, err := paymentCreator.WalletSign(ctx, createrAddr, vb)
+	if err != nil {
+		t.Fatal(err)
+	}
+	vouch.Signature = sig
+	_, err = paymentReceiver.PaychVoucherAdd(ctx, channel, vouch, nil, abi.NewTokenAmount(1000))
+	if err == nil {
+		t.Fatal(fmt.Errorf("Expected shortfall error of %d", excessAmt))
+	}
+
 	// wait for the settlement period to pass before collecting
-	waitForBlocks(ctx, t, bm, paymentReceiver, receiverAddr, paych.SettleDelay)
+	waitForBlocks(ctx, t, bm, paymentReceiver, receiverAddr, paych0.SettleDelay)

 	creatorPreCollectBalance, err := paymentCreator.WalletBalance(ctx, createrAddr)
 	if err != nil {
@@ -226,7 +284,7 @@ func waitForBlocks(ctx context.Context, t *testing.T, bm *BlockMiner, paymentRec

 		// Add a real block
 		m, err := paymentReceiver.MpoolPushMessage(ctx, &types.Message{
-			To:    builtin.BurntFundsActorAddr,
+			To:    builtin0.BurntFundsActorAddr,
 			From:  receiverAddr,
 			Value: types.NewInt(0),
 		}, nil)
@@ -12,6 +12,7 @@ import (
 	"github.com/filecoin-project/lotus/api"
 	"github.com/filecoin-project/lotus/build"
 	"github.com/filecoin-project/lotus/miner"
+	"github.com/filecoin-project/lotus/node"
 )

 type TestNode struct {
@@ -44,7 +45,7 @@ type StorageMiner struct {
 //
 // storage array defines storage nodes, numbers in the array specify full node
 // index the storage node 'belongs' to
-type APIBuilder func(t *testing.T, nFull int, storage []StorageMiner) ([]TestNode, []TestStorageNode)
+type APIBuilder func(t *testing.T, nFull int, storage []StorageMiner, opts ...node.Option) ([]TestNode, []TestStorageNode)
 type testSuite struct {
 	makeNodes APIBuilder
 }
@@ -15,9 +15,11 @@ import (
 	"github.com/filecoin-project/go-state-types/abi"
 	"github.com/filecoin-project/lotus/extern/sector-storage/mock"
 	sealing "github.com/filecoin-project/lotus/extern/storage-sealing"
+	"github.com/filecoin-project/lotus/node"

 	"github.com/filecoin-project/lotus/api"
 	"github.com/filecoin-project/lotus/build"
+	"github.com/filecoin-project/lotus/chain/stmgr"
 	"github.com/filecoin-project/lotus/chain/types"
 	bminer "github.com/filecoin-project/lotus/miner"
 	"github.com/filecoin-project/lotus/node/impl"
@@ -114,8 +116,29 @@ func pledgeSectors(t *testing.T, ctx context.Context, miner TestStorageNode, n,
 }

 func TestWindowPost(t *testing.T, b APIBuilder, blocktime time.Duration, nSectors int) {
-	ctx := context.Background()
-	n, sn := b(t, 1, OneMiner)
+	for _, height := range []abi.ChainEpoch{
+		1,    // before
+		162,  // while sealing
+		5000, // while proving
+	} {
+		height := height // copy to satisfy lints
+		t.Run(fmt.Sprintf("upgrade-%d", height), func(t *testing.T) {
+			testWindowPostUpgrade(t, b, blocktime, nSectors, height)
+		})
+	}
+
+}
+func testWindowPostUpgrade(t *testing.T, b APIBuilder, blocktime time.Duration, nSectors int,
+	upgradeHeight abi.ChainEpoch) {
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	n, sn := b(t, 1, OneMiner, node.Override(new(stmgr.UpgradeSchedule), stmgr.UpgradeSchedule{{
+		Network:   build.ActorUpgradeNetworkVersion,
+		Height:    upgradeHeight,
+		Migration: stmgr.UpgradeActorsV2,
+	}}))
+
 	client := n[0].FullNode.(*impl.FullNodeAPI)
 	miner := sn[0]

@@ -129,17 +152,24 @@ func TestWindowPost(t *testing.T, b APIBuilder, blocktime time.Duration, nSector
 	}
 	build.Clock.Sleep(time.Second)

-	mine := true
 	done := make(chan struct{})
 	go func() {
 		defer close(done)
-		for mine {
+		for ctx.Err() == nil {
 			build.Clock.Sleep(blocktime)
 			if err := sn[0].MineOne(ctx, MineNext); err != nil {
+				if ctx.Err() != nil {
+					// context was canceled, ignore the error.
+					return
+				}
 				t.Error(err)
 			}
 		}
 	}()
+	defer func() {
+		cancel()
+		<-done
+	}()

 	pledgeSectors(t, ctx, miner, nSectors, 0, nil)

@@ -153,18 +183,16 @@ func TestWindowPost(t *testing.T, b APIBuilder, blocktime time.Duration, nSector
 	require.NoError(t, err)

 	fmt.Printf("Running one proving period\n")
+	fmt.Printf("End for head.Height > %d\n", di.PeriodStart+di.WPoStProvingPeriod+2)

 	for {
 		head, err := client.ChainHead(ctx)
 		require.NoError(t, err)

-		if head.Height() > di.PeriodStart+(di.WPoStProvingPeriod)+2 {
+		if head.Height() > di.PeriodStart+di.WPoStProvingPeriod+2 {
+			fmt.Printf("Now head.Height = %d\n", head.Height())
 			break
 		}
-
-		if head.Height()%100 == 0 {
-			fmt.Printf("@%d\n", head.Height())
-		}
 		build.Clock.Sleep(blocktime)
 	}

@@ -186,7 +214,6 @@ func TestWindowPost(t *testing.T, b APIBuilder, blocktime time.Duration, nSector
 		require.Greater(t, len(parts), 0)

 		secs := parts[0].AllSectors
-		require.NoError(t, err)
 		n, err := secs.Count()
 		require.NoError(t, err)
 		require.Equal(t, uint64(2), n)
@@ -210,7 +237,6 @@ func TestWindowPost(t *testing.T, b APIBuilder, blocktime time.Duration, nSector
 		require.Greater(t, len(parts), 0)

 		secs := parts[0].AllSectors
-		require.NoError(t, err)
 		n, err := secs.Count()
 		require.NoError(t, err)
 		require.Equal(t, uint64(2), n)
@@ -236,18 +262,17 @@ func TestWindowPost(t *testing.T, b APIBuilder, blocktime time.Duration, nSector
 	require.NoError(t, err)

 	fmt.Printf("Go through another PP, wait for sectors to become faulty\n")
+	fmt.Printf("End for head.Height > %d\n", di.PeriodStart+di.WPoStProvingPeriod+2)

 	for {
 		head, err := client.ChainHead(ctx)
 		require.NoError(t, err)

 		if head.Height() > di.PeriodStart+(di.WPoStProvingPeriod)+2 {
+			fmt.Printf("Now head.Height = %d\n", head.Height())
 			break
 		}

-		if head.Height()%100 == 0 {
-			fmt.Printf("@%d\n", head.Height())
-		}
 		build.Clock.Sleep(blocktime)
 	}

@@ -267,17 +292,17 @@ func TestWindowPost(t *testing.T, b APIBuilder, blocktime time.Duration, nSector
 	di, err = client.StateMinerProvingDeadline(ctx, maddr, types.EmptyTSK)
 	require.NoError(t, err)

+	fmt.Printf("End for head.Height > %d\n", di.PeriodStart+di.WPoStProvingPeriod+2)
+
 	for {
 		head, err := client.ChainHead(ctx)
 		require.NoError(t, err)

 		if head.Height() > di.PeriodStart+di.WPoStProvingPeriod+2 {
+			fmt.Printf("Now head.Height = %d\n", head.Height())
 			break
 		}

-		if head.Height()%100 == 0 {
-			fmt.Printf("@%d\n", head.Height())
-		}
 		build.Clock.Sleep(blocktime)
 	}

@@ -294,18 +319,19 @@ func TestWindowPost(t *testing.T, b APIBuilder, blocktime time.Duration, nSector
 	pledgeSectors(t, ctx, miner, 1, nSectors, nil)

 	{
-		// wait a bit more
-
-		head, err := client.ChainHead(ctx)
+		// Wait until proven.
+		di, err = client.StateMinerProvingDeadline(ctx, maddr, types.EmptyTSK)
 		require.NoError(t, err)

-		waitUntil := head.Height() + 10
+		waitUntil := di.PeriodStart + di.WPoStProvingPeriod + 2
+		fmt.Printf("End for head.Height > %d\n", waitUntil)

 		for {
 			head, err := client.ChainHead(ctx)
 			require.NoError(t, err)

 			if head.Height() > waitUntil {
+				fmt.Printf("Now head.Height = %d\n", head.Height())
 				break
 			}
 		}
@@ -318,7 +344,4 @@ func TestWindowPost(t *testing.T, b APIBuilder, blocktime time.Duration, nSector

 	sectors = p.MinerPower.RawBytePower.Uint64() / uint64(ssz)
 	require.Equal(t, nSectors+GenesisPreseals-2+1, int(sectors)) // -2 not recovered sectors + 1 just pledged
-
-	mine = false
-	<-done
 }
@@ -4,3 +4,9 @@
 /dns4/bootstrap-4.testnet.fildev.network/tcp/1347/p2p/12D3KooWPkL9LrKRQgHtq7kn9ecNhGU9QaziG8R5tX8v9v7t3h34
 /dns4/bootstrap-3.testnet.fildev.network/tcp/1347/p2p/12D3KooWKYSsbpgZ3HAjax5M1BXCwXLa6gVkUARciz7uN3FNtr7T
 /dns4/bootstrap-5.testnet.fildev.network/tcp/1347/p2p/12D3KooWQYzqnLASJAabyMpPb1GcWZvNSe7JDcRuhdRqonFoiK9W
+/dns4/lotus-bootstrap.forceup.cn/tcp/41778/p2p/12D3KooWFQsv3nRMUevZNWWsY1Wu6NUzUbawnWU5NcRhgKuJA37C
+/dns4/bootstrap-0.starpool.in/tcp/12757/p2p/12D3KooWGHpBMeZbestVEWkfdnC9u7p6uFHXL1n7m1ZBqsEmiUzz
+/dns4/bootstrap-1.starpool.in/tcp/12757/p2p/12D3KooWQZrGH1PxSNZPum99M1zNvjNFM33d1AAu5DcvdHptuU7u
+/dns4/node.glif.io/tcp/1235/p2p/12D3KooWBF8cpp65hp2u9LK5mh19x67ftAam84z9LsfaquTDSBpt
+/dns4/bootstrap-0.ipfsmain.cn/tcp/34721/p2p/12D3KooWQnwEGNqcM2nAcPtRR9rAX8Hrg4k9kJLCHoTR5chJfz6d
+/dns4/bootstrap-1.ipfsmain.cn/tcp/34723/p2p/12D3KooWMKxMkD5DMpSWsW7dBddKxKT7L2GgbNuckz9otxvkvByP
@@ -3,28 +3,37 @@
 package build

 import (
+	"math"
+	"os"
+
 	"github.com/filecoin-project/go-state-types/abi"
-	"github.com/filecoin-project/go-state-types/big"
-	miner0 "github.com/filecoin-project/specs-actors/actors/builtin/miner"
-	power0 "github.com/filecoin-project/specs-actors/actors/builtin/power"
-	verifreg0 "github.com/filecoin-project/specs-actors/actors/builtin/verifreg"
+
+	"github.com/filecoin-project/lotus/chain/actors/policy"
 )

 const UpgradeBreezeHeight = -1
 const BreezeGasTampingDuration = 0

 const UpgradeSmokeHeight = -1
+const UpgradeIgnitionHeight = -2
+const UpgradeRefuelHeight = -3
+
+var UpgradeActorsV2Height = abi.ChainEpoch(10)
+var UpgradeLiftoffHeight = abi.ChainEpoch(-4)

 var DrandSchedule = map[abi.ChainEpoch]DrandEnum{
 	0: DrandMainnet,
 }

 func init() {
-	power0.ConsensusMinerMinPower = big.NewInt(2048)
-	miner0.SupportedProofTypes = map[abi.RegisteredSealProof]struct{}{
-		abi.RegisteredSealProof_StackedDrg2KiBV1: {},
+	policy.SetSupportedProofTypes(abi.RegisteredSealProof_StackedDrg2KiBV1)
+	policy.SetConsensusMinerMinPower(abi.NewStoragePower(2048))
+	policy.SetMinVerifiedDealSize(abi.NewStoragePower(256))
+
+	if os.Getenv("LOTUS_DISABLE_V2_ACTOR_MIGRATION") == "1" {
+		UpgradeActorsV2Height = math.MaxInt64
+		UpgradeLiftoffHeight = 11
 	}
-	verifreg0.MinVerifiedDealSize = big.NewInt(256)

 	BuildType |= Build2k
 }
@@ -3,6 +3,8 @@ package build
 import (
 	"sort"

+	"github.com/filecoin-project/go-address"
+
 	"github.com/libp2p/go-libp2p-core/protocol"

 	"github.com/filecoin-project/go-state-types/abi"
@@ -39,8 +41,12 @@ func DhtProtocolName(netName dtypes.NetworkName) protocol.ID {

 func UseNewestNetwork() bool {
 	// TODO: Put these in a container we can iterate over
-	if UpgradeBreezeHeight <= 0 && UpgradeSmokeHeight <= 0 {
+	if UpgradeBreezeHeight <= 0 && UpgradeSmokeHeight <= 0 && UpgradeActorsV2Height <= 0 {
 		return true
 	}
 	return false
 }
+
+func SetAddressNetwork(n address.Network) {
+	address.CurrentNetwork = n
+}
@@ -4,12 +4,15 @@ package build

 import (
 	"math/big"
+	"os"
+
+	"github.com/filecoin-project/go-address"
+	"github.com/filecoin-project/lotus/chain/actors/policy"

 	"github.com/filecoin-project/go-state-types/network"

 	"github.com/filecoin-project/go-state-types/abi"
 	"github.com/filecoin-project/specs-actors/actors/builtin"
-	miner0 "github.com/filecoin-project/specs-actors/actors/builtin/miner"
 )

 // /////
@@ -22,8 +25,8 @@ const UnixfsLinksPerLevel = 1024
 // Consensus / Network

 const AllowableClockDriftSecs = uint64(1)
-const NewestNetworkVersion = network.Version2
-const ActorUpgradeNetworkVersion = network.Version3
+const NewestNetworkVersion = network.Version4
+const ActorUpgradeNetworkVersion = network.Version4

 // Epochs
 const ForkLengthThreshold = Finality
@@ -32,7 +35,7 @@ const ForkLengthThreshold = Finality
 var BlocksPerEpoch = uint64(builtin.ExpectedLeadersPerEpoch)

 // Epochs
-const Finality = miner0.ChainFinality
+const Finality = policy.ChainFinality
 const MessageConfidence = uint64(5)

 // constants for Weight calculation
@@ -44,13 +47,8 @@ const WRatioDen = uint64(2)
 // Proofs

 // Epochs
-const SealRandomnessLookback = Finality
-
-// Epochs
-const SealRandomnessLookbackLimit = SealRandomnessLookback + 2000 // TODO: Get from spec specs-actors
-
-// Maximum lookback that randomness can be sourced from for a seal proof submission
-const MaxSealLookback = SealRandomnessLookbackLimit + 2000 // TODO: Get from specs-actors
+// TODO: unused
+const SealRandomnessLookback = policy.SealRandomnessLookback

 // /////
 // Mining
@@ -58,23 +56,37 @@ const MaxSealLookback = SealRandomnessLookbackLimit + 2000 // TODO: Get from spe
 // Epochs
 const TicketRandomnessLookback = abi.ChainEpoch(1)

-const WinningPoStSectorSetLookback = abi.ChainEpoch(10)
+// /////
+// Address
+
+const AddressMainnetEnvVar = "_mainnet_"

 // /////
 // Devnet settings

+var Devnet = true
+
 const FilBase = uint64(2_000_000_000)
 const FilAllocStorageMining = uint64(1_100_000_000)

 const FilecoinPrecision = uint64(1_000_000_000_000_000_000)
+const FilReserved = uint64(300_000_000)

 var InitialRewardBalance *big.Int
+var InitialFilReserved *big.Int

 // TODO: Move other important consts here

 func init() {
 	InitialRewardBalance = big.NewInt(int64(FilAllocStorageMining))
 	InitialRewardBalance = InitialRewardBalance.Mul(InitialRewardBalance, big.NewInt(int64(FilecoinPrecision)))
+
+	InitialFilReserved = big.NewInt(int64(FilReserved))
+	InitialFilReserved = InitialFilReserved.Mul(InitialFilReserved, big.NewInt(int64(FilecoinPrecision)))
+
+	if os.Getenv("LOTUS_ADDRESS_TYPE") == AddressMainnetEnvVar {
+		SetAddressNetwork(address.Mainnet)
+	}
 }

 // Sync
@@ -13,7 +13,8 @@ import (
 	"github.com/filecoin-project/go-state-types/abi"
 	"github.com/filecoin-project/go-state-types/network"
 	"github.com/filecoin-project/specs-actors/actors/builtin"
-	miner0 "github.com/filecoin-project/specs-actors/actors/builtin/miner"
+
+	"github.com/filecoin-project/lotus/chain/actors/policy"
 )

 var (
@@ -32,7 +33,7 @@ var (

 	AllowableClockDriftSecs = uint64(1)

-	Finality            = miner0.ChainFinality
+	Finality            = policy.ChainFinality
 	ForkLengthThreshold = Finality

 	SlashablePowerDelay        = 20
@@ -47,15 +48,13 @@ var (
 	BlsSignatureCacheSize = 40000
 	VerifSigCacheSize     = 32000

-	SealRandomnessLookback      = Finality
-	SealRandomnessLookbackLimit = SealRandomnessLookback + 2000
-	MaxSealLookback             = SealRandomnessLookbackLimit + 2000
+	SealRandomnessLookback = policy.SealRandomnessLookback

-	TicketRandomnessLookback     = abi.ChainEpoch(1)
-	WinningPoStSectorSetLookback = abi.ChainEpoch(10)
+	TicketRandomnessLookback = abi.ChainEpoch(1)

 	FilBase               uint64 = 2_000_000_000
 	FilAllocStorageMining uint64 = 1_400_000_000
+	FilReserved           uint64 = 300_000_000

 	FilecoinPrecision uint64 = 1_000_000_000_000_000_000

@@ -64,6 +63,13 @@ var (
 		v = v.Mul(v, big.NewInt(int64(FilecoinPrecision)))
 		return v
 	}()
+
+	InitialFilReserved = func() *big.Int {
+		v := big.NewInt(int64(FilReserved))
+		v = v.Mul(v, big.NewInt(int64(FilecoinPrecision)))
+		return v
+	}()
+
 	// Actor consts
 	// TODO: Pull from actors when its made not private
 	MinDealDuration = abi.ChainEpoch(180 * builtin.EpochsInDay)
@@ -74,12 +80,18 @@ var (
 	UpgradeBreezeHeight      abi.ChainEpoch = -1
 	BreezeGasTampingDuration abi.ChainEpoch = 0

-	UpgradeSmokeHeight abi.ChainEpoch = -1
+	UpgradeSmokeHeight    abi.ChainEpoch = -1
+	UpgradeIgnitionHeight abi.ChainEpoch = -2
+	UpgradeRefuelHeight   abi.ChainEpoch = -3
+	UpgradeActorsV2Height abi.ChainEpoch = 10
+	UpgradeLiftoffHeight  abi.ChainEpoch = -4

 	DrandSchedule = map[abi.ChainEpoch]DrandEnum{
 		0: DrandMainnet,
 	}

-	NewestNetworkVersion       = network.Version2
-	ActorUpgradeNetworkVersion = network.Version3
+	NewestNetworkVersion       = network.Version4
+	ActorUpgradeNetworkVersion = network.Version4
+
+	Devnet = true
 )
@@ -5,11 +5,14 @@
 package build

 import (
+	"math"
+	"os"
+
+	"github.com/filecoin-project/go-address"
 	"github.com/filecoin-project/go-state-types/abi"
-	"github.com/filecoin-project/go-state-types/big"
-	"github.com/filecoin-project/specs-actors/actors/builtin"
-	miner0 "github.com/filecoin-project/specs-actors/actors/builtin/miner"
-	power0 "github.com/filecoin-project/specs-actors/actors/builtin/power"
+	"github.com/filecoin-project/lotus/chain/actors/policy"
+
+	builtin0 "github.com/filecoin-project/specs-actors/actors/builtin"
 )

 var DrandSchedule = map[abi.ChainEpoch]DrandEnum{
@@ -22,14 +25,34 @@ const BreezeGasTampingDuration = 120

 const UpgradeSmokeHeight = 51000

+const UpgradeIgnitionHeight = 94000
+const UpgradeRefuelHeight = 130800
+
+var UpgradeActorsV2Height = abi.ChainEpoch(138720)
+
+// This signals our tentative epoch for mainnet launch. Can make it later, but not earlier.
+// Miners, clients, developers, custodians all need time to prepare.
+// We still have upgrades and state changes to do, but can happen after signaling timing here.
+const UpgradeLiftoffHeight = 148888
+
 func init() {
-	power0.ConsensusMinerMinPower = big.NewInt(10 << 40)
-	miner0.SupportedProofTypes = map[abi.RegisteredSealProof]struct{}{
-		abi.RegisteredSealProof_StackedDrg32GiBV1: {},
-		abi.RegisteredSealProof_StackedDrg64GiBV1: {},
+	policy.SetConsensusMinerMinPower(abi.NewStoragePower(10 << 40))
+	policy.SetSupportedProofTypes(
+		abi.RegisteredSealProof_StackedDrg32GiBV1,
+		abi.RegisteredSealProof_StackedDrg64GiBV1,
+	)
+
+	if os.Getenv("LOTUS_USE_TEST_ADDRESSES") != "1" {
+		SetAddressNetwork(address.Mainnet)
 	}
+
+	if os.Getenv("LOTUS_DISABLE_V2_ACTOR_MIGRATION") == "1" {
+		UpgradeActorsV2Height = math.MaxInt64
+	}
+
+	Devnet = false
 }

-const BlockDelaySecs = uint64(builtin.EpochDurationSeconds)
+const BlockDelaySecs = uint64(builtin0.EpochDurationSeconds)

 const PropagationDelaySecs = uint64(6)
@@ -29,7 +29,7 @@ func buildType() string {
 }

 // BuildVersion is the local build version, set by build system
-const BuildVersion = "0.7.2"
+const BuildVersion = "0.9.0"

 func UserVersion() string {
 	return BuildVersion + buildType() + CurrentCommit
@@ -7,8 +7,11 @@ import (
 	"github.com/filecoin-project/go-state-types/abi"
 	"github.com/filecoin-project/go-state-types/cbor"
 	"github.com/filecoin-project/go-state-types/network"
-	"github.com/filecoin-project/lotus/chain/actors/builtin"
+
+	"github.com/filecoin-project/lotus/chain/actors"
+
 	adt0 "github.com/filecoin-project/specs-actors/actors/util/adt"
+	adt2 "github.com/filecoin-project/specs-actors/v2/actors/util/adt"
 )

 type Map interface {
@@ -21,18 +24,22 @@ type Map interface {
 	ForEach(v cbor.Unmarshaler, fn func(key string) error) error
 }

-func AsMap(store Store, root cid.Cid, version builtin.Version) (Map, error) {
+func AsMap(store Store, root cid.Cid, version actors.Version) (Map, error) {
 	switch version {
-	case builtin.Version0:
+	case actors.Version0:
 		return adt0.AsMap(store, root)
+	case actors.Version2:
+		return adt2.AsMap(store, root)
 	}
 	return nil, xerrors.Errorf("unknown network version: %d", version)
 }

-func NewMap(store Store, version builtin.Version) (Map, error) {
+func NewMap(store Store, version actors.Version) (Map, error) {
 	switch version {
-	case builtin.Version0:
+	case actors.Version0:
 		return adt0.MakeEmptyMap(store), nil
+	case actors.Version2:
+		return adt2.MakeEmptyMap(store), nil
 	}
 	return nil, xerrors.Errorf("unknown network version: %d", version)
 }
@@ -49,17 +56,21 @@ type Array interface {
 }

 func AsArray(store Store, root cid.Cid, version network.Version) (Array, error) {
-	switch builtin.VersionForNetwork(version) {
-	case builtin.Version0:
+	switch actors.VersionForNetwork(version) {
+	case actors.Version0:
 		return adt0.AsArray(store, root)
+	case actors.Version2:
+		return adt2.AsArray(store, root)
 	}
 	return nil, xerrors.Errorf("unknown network version: %d", version)
 }

-func NewArray(store Store, version builtin.Version) (Array, error) {
+func NewArray(store Store, version actors.Version) (Array, error) {
 	switch version {
-	case builtin.Version0:
+	case actors.Version0:
 		return adt0.MakeEmptyArray(store), nil
+	case actors.Version2:
+		return adt2.MakeEmptyArray(store), nil
 	}
 	return nil, xerrors.Errorf("unknown network version: %d", version)
 }
@@ -5,21 +5,31 @@ import (

 	"github.com/filecoin-project/go-address"
 	"github.com/filecoin-project/go-state-types/cbor"
-	builtin0 "github.com/filecoin-project/specs-actors/actors/builtin"
+	"github.com/ipfs/go-cid"

 	"github.com/filecoin-project/lotus/chain/actors/adt"
+	"github.com/filecoin-project/lotus/chain/actors/builtin"
 	"github.com/filecoin-project/lotus/chain/types"
+
+	builtin0 "github.com/filecoin-project/specs-actors/actors/builtin"
+	builtin2 "github.com/filecoin-project/specs-actors/v2/actors/builtin"
 )

+func init() {
+	builtin.RegisterActorState(builtin0.AccountActorCodeID, func(store adt.Store, root cid.Cid) (cbor.Marshaler, error) {
+		return load0(store, root)
+	})
+	builtin.RegisterActorState(builtin2.AccountActorCodeID, func(store adt.Store, root cid.Cid) (cbor.Marshaler, error) {
+		return load2(store, root)
+	})
+}
+
 func Load(store adt.Store, act *types.Actor) (State, error) {
 	switch act.Code {
 	case builtin0.AccountActorCodeID:
-		out := state0{store: store}
-		err := store.Get(store.Context(), act.Head, &out)
-		if err != nil {
-			return nil, err
-		}
-		return &out, nil
+		return load0(store, act.Head)
+	case builtin2.AccountActorCodeID:
+		return load2(store, act.Head)
 	}
 	return nil, xerrors.Errorf("unknown actor code %s", act.Code)
 }
@@ -2,14 +2,26 @@ package account

 import (
 	"github.com/filecoin-project/go-address"
+	"github.com/ipfs/go-cid"
+
 	"github.com/filecoin-project/lotus/chain/actors/adt"
-	"github.com/filecoin-project/specs-actors/actors/builtin/account"
+
+	account0 "github.com/filecoin-project/specs-actors/actors/builtin/account"
 )

 var _ State = (*state0)(nil)

+func load0(store adt.Store, root cid.Cid) (State, error) {
+	out := state0{store: store}
+	err := store.Get(store.Context(), root, &out)
+	if err != nil {
+		return nil, err
+	}
+	return &out, nil
+}
+
 type state0 struct {
-	account.State
+	account0.State
 	store adt.Store
 }

@@ -0,0 +1,30 @@
+package account
+
+import (
+	"github.com/filecoin-project/go-address"
+	"github.com/ipfs/go-cid"
+
+	"github.com/filecoin-project/lotus/chain/actors/adt"
+
+	account2 "github.com/filecoin-project/specs-actors/v2/actors/builtin/account"
+)
+
+var _ State = (*state2)(nil)
+
+func load2(store adt.Store, root cid.Cid) (State, error) {
+	out := state2{store: store}
+	err := store.Get(store.Context(), root, &out)
+	if err != nil {
+		return nil, err
+	}
+	return &out, nil
+}
+
+type state2 struct {
+	account2.State
+	store adt.Store
+}
+
+func (s *state2) PubkeyAddress() (address.Address, error) {
+	return s.Address, nil
+}
@@ -1,32 +1,28 @@
 package builtin

 import (
-	"fmt"
+	"github.com/filecoin-project/go-address"
+	"github.com/ipfs/go-cid"
+	"golang.org/x/xerrors"

 	"github.com/filecoin-project/go-state-types/abi"
+	"github.com/filecoin-project/go-state-types/cbor"
+
+	"github.com/filecoin-project/lotus/chain/actors/adt"
+	"github.com/filecoin-project/lotus/chain/types"
+
+	builtin0 "github.com/filecoin-project/specs-actors/actors/builtin"
 	miner0 "github.com/filecoin-project/specs-actors/actors/builtin/miner"
 	proof0 "github.com/filecoin-project/specs-actors/actors/runtime/proof"
-
 	smoothing0 "github.com/filecoin-project/specs-actors/actors/util/smoothing"
-
-	"github.com/filecoin-project/go-state-types/network"
+	builtin2 "github.com/filecoin-project/specs-actors/v2/actors/builtin"
+	smoothing2 "github.com/filecoin-project/specs-actors/v2/actors/util/smoothing"
 )

-type Version int
-
-const (
-	Version0 = iota
-)
-
-// Converts a network version into a specs-actors version.
-func VersionForNetwork(version network.Version) Version {
-	switch version {
-	case network.Version0, network.Version1, network.Version2:
-		return Version0
-	default:
-		panic(fmt.Sprintf("unsupported network version %d", version))
-	}
-}
+var SystemActorAddr = builtin0.SystemActorAddr
+var BurntFundsActorAddr = builtin0.BurntFundsActorAddr
+var ReserveAddress = makeAddress("t090")
+var RootVerifierAddress = makeAddress("t080")

 // TODO: Why does actors have 2 different versions of this?
 type SectorInfo = proof0.SectorInfo
@@ -41,3 +37,64 @@ func FromV0FilterEstimate(v0 smoothing0.FilterEstimate) FilterEstimate {
 func QAPowerForWeight(size abi.SectorSize, duration abi.ChainEpoch, dealWeight, verifiedWeight abi.DealWeight) abi.StoragePower {
 	return miner0.QAPowerForWeight(size, duration, dealWeight, verifiedWeight)
 }
+
+func FromV2FilterEstimate(v1 smoothing2.FilterEstimate) FilterEstimate {
+	return (FilterEstimate)(v1)
+}
+
+type ActorStateLoader func(store adt.Store, root cid.Cid) (cbor.Marshaler, error)
+
+var ActorStateLoaders = make(map[cid.Cid]ActorStateLoader)
+
+func RegisterActorState(code cid.Cid, loader ActorStateLoader) {
+	ActorStateLoaders[code] = loader
+}
+
+func Load(store adt.Store, act *types.Actor) (cbor.Marshaler, error) {
+	loader, found := ActorStateLoaders[act.Code]
+	if !found {
+		return nil, xerrors.Errorf("unknown actor code %s", act.Code)
+	}
+	return loader(store, act.Head)
+}
+
+func ActorNameByCode(c cid.Cid) string {
+	switch {
+	case builtin0.IsBuiltinActor(c):
+		return builtin0.ActorNameByCode(c)
+	case builtin2.IsBuiltinActor(c):
+		return builtin2.ActorNameByCode(c)
+	default:
+		return "<unknown>"
+	}
+}
+
+func IsBuiltinActor(c cid.Cid) bool {
+	return builtin0.IsBuiltinActor(c) || builtin2.IsBuiltinActor(c)
+}
+
+func IsAccountActor(c cid.Cid) bool {
+	return c == builtin0.AccountActorCodeID || c == builtin2.AccountActorCodeID
+}
+
+func IsStorageMinerActor(c cid.Cid) bool {
+	return c == builtin0.StorageMinerActorCodeID || c == builtin2.StorageMinerActorCodeID
+}
+
+func IsMultisigActor(c cid.Cid) bool {
+	return c == builtin0.MultisigActorCodeID || c == builtin2.MultisigActorCodeID
+
+}
+
+func IsPaymentChannelActor(c cid.Cid) bool {
+	return c == builtin0.PaymentChannelActorCodeID || c == builtin2.PaymentChannelActorCodeID
+}
+
+func makeAddress(addr string) address.Address {
+	ret, err := address.NewFromString(addr)
+	if err != nil {
+		panic(err)
+	}
+
+	return ret
+}
@@ -6,24 +6,34 @@ import (
 	"github.com/filecoin-project/go-address"
 	"github.com/filecoin-project/go-state-types/abi"
 	"github.com/filecoin-project/go-state-types/cbor"
-	builtin0 "github.com/filecoin-project/specs-actors/actors/builtin"
+	"github.com/ipfs/go-cid"

 	"github.com/filecoin-project/lotus/chain/actors/adt"
+	"github.com/filecoin-project/lotus/chain/actors/builtin"
 	"github.com/filecoin-project/lotus/chain/types"
 	"github.com/filecoin-project/lotus/node/modules/dtypes"
+
+	builtin0 "github.com/filecoin-project/specs-actors/actors/builtin"
+	builtin2 "github.com/filecoin-project/specs-actors/v2/actors/builtin"
 )

+func init() {
+	builtin.RegisterActorState(builtin0.InitActorCodeID, func(store adt.Store, root cid.Cid) (cbor.Marshaler, error) {
+		return load0(store, root)
+	})
+	builtin.RegisterActorState(builtin2.InitActorCodeID, func(store adt.Store, root cid.Cid) (cbor.Marshaler, error) {
+		return load2(store, root)
+	})
+}
+
 var Address = builtin0.InitActorAddr

 func Load(store adt.Store, act *types.Actor) (State, error) {
 	switch act.Code {
 	case builtin0.InitActorCodeID:
-		out := state0{store: store}
-		err := store.Get(store.Context(), act.Head, &out)
-		if err != nil {
-			return nil, err
-		}
-		return &out, nil
+		return load0(store, act.Head)
+	case builtin2.InitActorCodeID:
+		return load2(store, act.Head)
 	}
 	return nil, xerrors.Errorf("unknown actor code %s", act.Code)
 }
@@ -41,4 +51,7 @@ type State interface {
 	// It should not be used in production code, as init actor entries are
 	// immutable.
 	Remove(addrs ...address.Address) error
+
+	// Sets the network's name. This should only be used on upgrade/fork.
+	SetNetworkName(name string) error
 }
@@ -3,21 +3,30 @@ package init
 import (
 	"github.com/filecoin-project/go-address"
 	"github.com/filecoin-project/go-state-types/abi"
+	"github.com/ipfs/go-cid"
 	cbg "github.com/whyrusleeping/cbor-gen"
 	"golang.org/x/xerrors"

-	init_ "github.com/filecoin-project/specs-actors/actors/builtin/init"
-
 	"github.com/filecoin-project/lotus/chain/actors/adt"
 	"github.com/filecoin-project/lotus/node/modules/dtypes"

+	init0 "github.com/filecoin-project/specs-actors/actors/builtin/init"
 	adt0 "github.com/filecoin-project/specs-actors/actors/util/adt"
 )

 var _ State = (*state0)(nil)

+func load0(store adt.Store, root cid.Cid) (State, error) {
+	out := state0{store: store}
+	err := store.Get(store.Context(), root, &out)
+	if err != nil {
+		return nil, err
+	}
+	return &out, nil
+}
+
 type state0 struct {
-	init_.State
+	init0.State
 	store adt.Store
 }

@@ -48,6 +57,11 @@ func (s *state0) NetworkName() (dtypes.NetworkName, error) {
 	return dtypes.NetworkName(s.State.NetworkName), nil
 }

+func (s *state0) SetNetworkName(name string) error {
+	s.State.NetworkName = name
+	return nil
+}
+
 func (s *state0) Remove(addrs ...address.Address) (err error) {
 	m, err := adt0.AsMap(s.store, s.State.AddressMap)
 	if err != nil {
@@ -0,0 +1,81 @@
+package init
+
+import (
+	"github.com/filecoin-project/go-address"
+	"github.com/filecoin-project/go-state-types/abi"
+	"github.com/ipfs/go-cid"
+	cbg "github.com/whyrusleeping/cbor-gen"
+	"golang.org/x/xerrors"
+
+	"github.com/filecoin-project/lotus/chain/actors/adt"
+	"github.com/filecoin-project/lotus/node/modules/dtypes"
+
+	init2 "github.com/filecoin-project/specs-actors/v2/actors/builtin/init"
+	adt2 "github.com/filecoin-project/specs-actors/v2/actors/util/adt"
+)
+
+var _ State = (*state2)(nil)
+
+func load2(store adt.Store, root cid.Cid) (State, error) {
+	out := state2{store: store}
+	err := store.Get(store.Context(), root, &out)
+	if err != nil {
+		return nil, err
+	}
+	return &out, nil
+}
+
+type state2 struct {
+	init2.State
+	store adt.Store
+}
+
+func (s *state2) ResolveAddress(address address.Address) (address.Address, bool, error) {
+	return s.State.ResolveAddress(s.store, address)
+}
+
+func (s *state2) MapAddressToNewID(address address.Address) (address.Address, error) {
+	return s.State.MapAddressToNewID(s.store, address)
+}
+
+func (s *state2) ForEachActor(cb func(id abi.ActorID, address address.Address) error) error {
+	addrs, err := adt2.AsMap(s.store, s.State.AddressMap)
+	if err != nil {
+		return err
+	}
+	var actorID cbg.CborInt
+	return addrs.ForEach(&actorID, func(key string) error {
+		addr, err := address.NewFromBytes([]byte(key))
+		if err != nil {
+			return err
+		}
+		return cb(abi.ActorID(actorID), addr)
+	})
+}
+
+func (s *state2) NetworkName() (dtypes.NetworkName, error) {
+	return dtypes.NetworkName(s.State.NetworkName), nil
+}
+
+func (s *state2) SetNetworkName(name string) error {
+	s.State.NetworkName = name
+	return nil
+}
+
+func (s *state2) Remove(addrs ...address.Address) (err error) {
+	m, err := adt2.AsMap(s.store, s.State.AddressMap)
+	if err != nil {
+		return err
+	}
+	for _, addr := range addrs {
+		if err = m.Delete(abi.AddrKey(addr)); err != nil {
+			return xerrors.Errorf("failed to delete entry for address: %s; err: %w", addr, err)
+		}
+	}
+	amr, err := m.Root()
+	if err != nil {
+		return xerrors.Errorf("failed to get address map root: %w", err)
+	}
+	s.State.AddressMap = amr
+	return nil
+}
@@ -6,26 +6,35 @@ import (
 	"github.com/filecoin-project/go-address"
 	"github.com/filecoin-project/go-state-types/abi"
 	"github.com/filecoin-project/go-state-types/cbor"
-	builtin0 "github.com/filecoin-project/specs-actors/actors/builtin"
-	market0 "github.com/filecoin-project/specs-actors/actors/builtin/market"
 	"github.com/ipfs/go-cid"
 	cbg "github.com/whyrusleeping/cbor-gen"

+	builtin0 "github.com/filecoin-project/specs-actors/actors/builtin"
+	market0 "github.com/filecoin-project/specs-actors/actors/builtin/market"
+	builtin2 "github.com/filecoin-project/specs-actors/v2/actors/builtin"
+
 	"github.com/filecoin-project/lotus/chain/actors/adt"
+	"github.com/filecoin-project/lotus/chain/actors/builtin"
 	"github.com/filecoin-project/lotus/chain/types"
 )

+func init() {
+	builtin.RegisterActorState(builtin0.StorageMarketActorCodeID, func(store adt.Store, root cid.Cid) (cbor.Marshaler, error) {
+		return load0(store, root)
+	})
+	builtin.RegisterActorState(builtin2.StorageMarketActorCodeID, func(store adt.Store, root cid.Cid) (cbor.Marshaler, error) {
+		return load2(store, root)
+	})
+}
+
 var Address = builtin0.StorageMarketActorAddr

 func Load(store adt.Store, act *types.Actor) (st State, err error) {
 	switch act.Code {
 	case builtin0.StorageMarketActorCodeID:
-		out := state0{store: store}
-		err := store.Get(store.Context(), act.Head, &out)
-		if err != nil {
-			return nil, err
-		}
-		return &out, nil
+		return load0(store, act.Head)
+	case builtin2.StorageMarketActorCodeID:
+		return load2(store, act.Head)
 	}
 	return nil, xerrors.Errorf("unknown actor code %s", act.Code)
 }
@@ -5,17 +5,29 @@ import (

 	"github.com/filecoin-project/go-address"
 	"github.com/filecoin-project/go-state-types/abi"
+	"github.com/ipfs/go-cid"
+	cbg "github.com/whyrusleeping/cbor-gen"
+
 	"github.com/filecoin-project/lotus/chain/actors/adt"
 	"github.com/filecoin-project/lotus/chain/types"
-	"github.com/filecoin-project/specs-actors/actors/builtin/market"
+
+	market0 "github.com/filecoin-project/specs-actors/actors/builtin/market"
 	adt0 "github.com/filecoin-project/specs-actors/actors/util/adt"
-	cbg "github.com/whyrusleeping/cbor-gen"
 )

 var _ State = (*state0)(nil)

+func load0(store adt.Store, root cid.Cid) (State, error) {
+	out := state0{store: store}
+	err := store.Get(store.Context(), root, &out)
+	if err != nil {
+		return nil, err
+	}
+	return &out, nil
+}
+
 type state0 struct {
-	market.State
+	market0.State
 	store adt.Store
 }

@@ -90,7 +102,7 @@ func (s *state0) LockedTable() (BalanceTable, error) {
 func (s *state0) VerifyDealsForActivation(
 	minerAddr address.Address, deals []abi.DealID, currEpoch, sectorExpiry abi.ChainEpoch,
 ) (weight, verifiedWeight abi.DealWeight, err error) {
-	return market.ValidateDealsForActivation(&s.State, s.store, deals, minerAddr, sectorExpiry, currEpoch)
+	return market0.ValidateDealsForActivation(&s.State, s.store, deals, minerAddr, sectorExpiry, currEpoch)
 }

 type balanceTable0 struct {
@@ -114,7 +126,7 @@ type dealStates0 struct {
 }

 func (s *dealStates0) Get(dealID abi.DealID) (*DealState, bool, error) {
-	var deal0 market.DealState
+	var deal0 market0.DealState
 	found, err := s.Array.Get(uint64(dealID), &deal0)
 	if err != nil {
 		return nil, false, err
@@ -127,14 +139,14 @@ func (s *dealStates0) Get(dealID abi.DealID) (*DealState, bool, error) {
 }

 func (s *dealStates0) ForEach(cb func(dealID abi.DealID, ds DealState) error) error {
-	var ds0 market.DealState
+	var ds0 market0.DealState
 	return s.Array.ForEach(&ds0, func(idx int64) error {
 		return cb(abi.DealID(idx), fromV0DealState(ds0))
 	})
 }

 func (s *dealStates0) decode(val *cbg.Deferred) (*DealState, error) {
-	var ds0 market.DealState
+	var ds0 market0.DealState
 	if err := ds0.UnmarshalCBOR(bytes.NewReader(val.Raw)); err != nil {
 		return nil, err
 	}
@@ -146,7 +158,7 @@ func (s *dealStates0) array() adt.Array {
 	return s.Array
 }

-func fromV0DealState(v0 market.DealState) DealState {
+func fromV0DealState(v0 market0.DealState) DealState {
 	return (DealState)(v0)
 }

@@ -155,7 +167,7 @@ type dealProposals0 struct {
 }

 func (s *dealProposals0) Get(dealID abi.DealID) (*DealProposal, bool, error) {
-	var proposal0 market.DealProposal
+	var proposal0 market0.DealProposal
 	found, err := s.Array.Get(uint64(dealID), &proposal0)
 	if err != nil {
 		return nil, false, err
@@ -168,14 +180,14 @@ func (s *dealProposals0) Get(dealID abi.DealID) (*DealProposal, bool, error) {
 }

 func (s *dealProposals0) ForEach(cb func(dealID abi.DealID, dp DealProposal) error) error {
-	var dp0 market.DealProposal
+	var dp0 market0.DealProposal
 	return s.Array.ForEach(&dp0, func(idx int64) error {
 		return cb(abi.DealID(idx), fromV0DealProposal(dp0))
 	})
 }

 func (s *dealProposals0) decode(val *cbg.Deferred) (*DealProposal, error) {
-	var dp0 market.DealProposal
+	var dp0 market0.DealProposal
 	if err := dp0.UnmarshalCBOR(bytes.NewReader(val.Raw)); err != nil {
 		return nil, err
 	}
@@ -187,6 +199,6 @@ func (s *dealProposals0) array() adt.Array {
 	return s.Array
 }

-func fromV0DealProposal(v0 market.DealProposal) DealProposal {
+func fromV0DealProposal(v0 market0.DealProposal) DealProposal {
 	return (DealProposal)(v0)
 }
@@ -0,0 +1,205 @@
+package market
+
+import (
+	"bytes"
+
+	"github.com/filecoin-project/go-address"
+	"github.com/filecoin-project/go-state-types/abi"
+	"github.com/ipfs/go-cid"
+	cbg "github.com/whyrusleeping/cbor-gen"
+
+	"github.com/filecoin-project/lotus/chain/actors/adt"
+	"github.com/filecoin-project/lotus/chain/types"
+
+	market2 "github.com/filecoin-project/specs-actors/v2/actors/builtin/market"
+	adt2 "github.com/filecoin-project/specs-actors/v2/actors/util/adt"
+)
+
+var _ State = (*state2)(nil)
+
+func load2(store adt.Store, root cid.Cid) (State, error) {
+	out := state2{store: store}
+	err := store.Get(store.Context(), root, &out)
+	if err != nil {
+		return nil, err
+	}
+	return &out, nil
+}
+
+type state2 struct {
+	market2.State
+	store adt.Store
+}
+
+func (s *state2) TotalLocked() (abi.TokenAmount, error) {
+	fml := types.BigAdd(s.TotalClientLockedCollateral, s.TotalProviderLockedCollateral)
+	fml = types.BigAdd(fml, s.TotalClientStorageFee)
+	return fml, nil
+}
+
+func (s *state2) BalancesChanged(otherState State) (bool, error) {
+	otherState2, ok := otherState.(*state2)
+	if !ok {
+		// there's no way to compare different versions of the state, so let's
+		// just say that means the state of balances has changed
+		return true, nil
+	}
+	return !s.State.EscrowTable.Equals(otherState2.State.EscrowTable) || !s.State.LockedTable.Equals(otherState2.State.LockedTable), nil
+}
+
+func (s *state2) StatesChanged(otherState State) (bool, error) {
+	otherState2, ok := otherState.(*state2)
+	if !ok {
+		// there's no way to compare different versions of the state, so let's
+		// just say that means the state of balances has changed
+		return true, nil
+	}
+	return !s.State.States.Equals(otherState2.State.States), nil
+}
+
+func (s *state2) States() (DealStates, error) {
+	stateArray, err := adt2.AsArray(s.store, s.State.States)
+	if err != nil {
+		return nil, err
+	}
+	return &dealStates2{stateArray}, nil
+}
+
+func (s *state2) ProposalsChanged(otherState State) (bool, error) {
+	otherState2, ok := otherState.(*state2)
+	if !ok {
+		// there's no way to compare different versions of the state, so let's
+		// just say that means the state of balances has changed
+		return true, nil
+	}
+	return !s.State.Proposals.Equals(otherState2.State.Proposals), nil
+}
+
+func (s *state2) Proposals() (DealProposals, error) {
+	proposalArray, err := adt2.AsArray(s.store, s.State.Proposals)
+	if err != nil {
+		return nil, err
+	}
+	return &dealProposals2{proposalArray}, nil
+}
+
+func (s *state2) EscrowTable() (BalanceTable, error) {
+	bt, err := adt2.AsBalanceTable(s.store, s.State.EscrowTable)
+	if err != nil {
+		return nil, err
+	}
+	return &balanceTable2{bt}, nil
+}
+
+func (s *state2) LockedTable() (BalanceTable, error) {
+	bt, err := adt2.AsBalanceTable(s.store, s.State.LockedTable)
+	if err != nil {
+		return nil, err
+	}
+	return &balanceTable2{bt}, nil
+}
+
+func (s *state2) VerifyDealsForActivation(
+	minerAddr address.Address, deals []abi.DealID, currEpoch, sectorExpiry abi.ChainEpoch,
+) (weight, verifiedWeight abi.DealWeight, err error) {
+	w, vw, _, err := market2.ValidateDealsForActivation(&s.State, s.store, deals, minerAddr, sectorExpiry, currEpoch)
+	return w, vw, err
+}
+
+type balanceTable2 struct {
+	*adt2.BalanceTable
+}
+
+func (bt *balanceTable2) ForEach(cb func(address.Address, abi.TokenAmount) error) error {
+	asMap := (*adt2.Map)(bt.BalanceTable)
+	var ta abi.TokenAmount
+	return asMap.ForEach(&ta, func(key string) error {
+		a, err := address.NewFromBytes([]byte(key))
+		if err != nil {
+			return err
+		}
+		return cb(a, ta)
+	})
+}
+
+type dealStates2 struct {
+	adt.Array
+}
+
+func (s *dealStates2) Get(dealID abi.DealID) (*DealState, bool, error) {
+	var deal2 market2.DealState
+	found, err := s.Array.Get(uint64(dealID), &deal2)
+	if err != nil {
+		return nil, false, err
+	}
+	if !found {
+		return nil, false, nil
+	}
+	deal := fromV2DealState(deal2)
+	return &deal, true, nil
+}
+
+func (s *dealStates2) ForEach(cb func(dealID abi.DealID, ds DealState) error) error {
+	var ds1 market2.DealState
+	return s.Array.ForEach(&ds1, func(idx int64) error {
+		return cb(abi.DealID(idx), fromV2DealState(ds1))
+	})
+}
+
+func (s *dealStates2) decode(val *cbg.Deferred) (*DealState, error) {
+	var ds1 market2.DealState
+	if err := ds1.UnmarshalCBOR(bytes.NewReader(val.Raw)); err != nil {
+		return nil, err
+	}
+	ds := fromV2DealState(ds1)
+	return &ds, nil
+}
+
+func (s *dealStates2) array() adt.Array {
+	return s.Array
+}
+
+func fromV2DealState(v1 market2.DealState) DealState {
+	return (DealState)(v1)
+}
+
+type dealProposals2 struct {
+	adt.Array
+}
+
+func (s *dealProposals2) Get(dealID abi.DealID) (*DealProposal, bool, error) {
+	var proposal2 market2.DealProposal
+	found, err := s.Array.Get(uint64(dealID), &proposal2)
+	if err != nil {
+		return nil, false, err
+	}
+	if !found {
+		return nil, false, nil
+	}
+	proposal := fromV2DealProposal(proposal2)
+	return &proposal, true, nil
+}
+
+func (s *dealProposals2) ForEach(cb func(dealID abi.DealID, dp DealProposal) error) error {
+	var dp1 market2.DealProposal
+	return s.Array.ForEach(&dp1, func(idx int64) error {
+		return cb(abi.DealID(idx), fromV2DealProposal(dp1))
+	})
+}
+
+func (s *dealProposals2) decode(val *cbg.Deferred) (*DealProposal, error) {
+	var dp1 market2.DealProposal
+	if err := dp1.UnmarshalCBOR(bytes.NewReader(val.Raw)); err != nil {
+		return nil, err
+	}
+	dp := fromV2DealProposal(dp1)
+	return &dp, nil
+}
+
+func (s *dealProposals2) array() adt.Array {
+	return s.Array
+}
+
+func fromV2DealProposal(v1 market2.DealProposal) DealProposal {
+	return (DealProposal)(v1)
+}
@@ -1,313 +0,0 @@
-// Code generated by github.com/whyrusleeping/cbor-gen. DO NOT EDIT.
-
-package miner
-
-import (
-	"fmt"
-	"io"
-
-	abi "github.com/filecoin-project/go-state-types/abi"
-	cbg "github.com/whyrusleeping/cbor-gen"
-	xerrors "golang.org/x/xerrors"
-)
-
-var _ = xerrors.Errorf
-
-var lengthBufSectorOnChainInfo = []byte{139}
-
-func (t *SectorOnChainInfo) MarshalCBOR(w io.Writer) error {
-	if t == nil {
-		_, err := w.Write(cbg.CborNull)
-		return err
-	}
-	if _, err := w.Write(lengthBufSectorOnChainInfo); err != nil {
-		return err
-	}
-
-	scratch := make([]byte, 9)
-
-	// t.SectorNumber (abi.SectorNumber) (uint64)
-
-	if err := cbg.WriteMajorTypeHeaderBuf(scratch, w, cbg.MajUnsignedInt, uint64(t.SectorNumber)); err != nil {
-		return err
-	}
-
-	// t.SealProof (abi.RegisteredSealProof) (int64)
-	if t.SealProof >= 0 {
-		if err := cbg.WriteMajorTypeHeaderBuf(scratch, w, cbg.MajUnsignedInt, uint64(t.SealProof)); err != nil {
-			return err
-		}
-	} else {
-		if err := cbg.WriteMajorTypeHeaderBuf(scratch, w, cbg.MajNegativeInt, uint64(-t.SealProof-1)); err != nil {
-			return err
-		}
-	}
-
-	// t.SealedCID (cid.Cid) (struct)
-
-	if err := cbg.WriteCidBuf(scratch, w, t.SealedCID); err != nil {
-		return xerrors.Errorf("failed to write cid field t.SealedCID: %w", err)
-	}
-
-	// t.DealIDs ([]abi.DealID) (slice)
-	if len(t.DealIDs) > cbg.MaxLength {
-		return xerrors.Errorf("Slice value in field t.DealIDs was too long")
-	}
-
-	if err := cbg.WriteMajorTypeHeaderBuf(scratch, w, cbg.MajArray, uint64(len(t.DealIDs))); err != nil {
-		return err
-	}
-	for _, v := range t.DealIDs {
-		if err := cbg.CborWriteHeader(w, cbg.MajUnsignedInt, uint64(v)); err != nil {
-			return err
-		}
-	}
-
-	// t.Activation (abi.ChainEpoch) (int64)
-	if t.Activation >= 0 {
-		if err := cbg.WriteMajorTypeHeaderBuf(scratch, w, cbg.MajUnsignedInt, uint64(t.Activation)); err != nil {
-			return err
-		}
-	} else {
-		if err := cbg.WriteMajorTypeHeaderBuf(scratch, w, cbg.MajNegativeInt, uint64(-t.Activation-1)); err != nil {
-			return err
-		}
-	}
-
-	// t.Expiration (abi.ChainEpoch) (int64)
-	if t.Expiration >= 0 {
-		if err := cbg.WriteMajorTypeHeaderBuf(scratch, w, cbg.MajUnsignedInt, uint64(t.Expiration)); err != nil {
-			return err
-		}
-	} else {
-		if err := cbg.WriteMajorTypeHeaderBuf(scratch, w, cbg.MajNegativeInt, uint64(-t.Expiration-1)); err != nil {
-			return err
-		}
-	}
-
-	// t.DealWeight (big.Int) (struct)
-	if err := t.DealWeight.MarshalCBOR(w); err != nil {
-		return err
-	}
-
-	// t.VerifiedDealWeight (big.Int) (struct)
-	if err := t.VerifiedDealWeight.MarshalCBOR(w); err != nil {
-		return err
-	}
-
-	// t.InitialPledge (big.Int) (struct)
-	if err := t.InitialPledge.MarshalCBOR(w); err != nil {
-		return err
-	}
-
-	// t.ExpectedDayReward (big.Int) (struct)
-	if err := t.ExpectedDayReward.MarshalCBOR(w); err != nil {
-		return err
-	}
-
-	// t.ExpectedStoragePledge (big.Int) (struct)
-	if err := t.ExpectedStoragePledge.MarshalCBOR(w); err != nil {
-		return err
-	}
-	return nil
-}
-
-func (t *SectorOnChainInfo) UnmarshalCBOR(r io.Reader) error {
-	*t = SectorOnChainInfo{}
-
-	br := cbg.GetPeeker(r)
-	scratch := make([]byte, 8)
-
-	maj, extra, err := cbg.CborReadHeaderBuf(br, scratch)
-	if err != nil {
-		return err
-	}
-	if maj != cbg.MajArray {
-		return fmt.Errorf("cbor input should be of type array")
-	}
-
-	if extra != 11 {
-		return fmt.Errorf("cbor input had wrong number of fields")
-	}
-
-	// t.SectorNumber (abi.SectorNumber) (uint64)
-
-	{
-
-		maj, extra, err = cbg.CborReadHeaderBuf(br, scratch)
-		if err != nil {
-			return err
-		}
-		if maj != cbg.MajUnsignedInt {
-			return fmt.Errorf("wrong type for uint64 field")
-		}
-		t.SectorNumber = abi.SectorNumber(extra)
-
-	}
-	// t.SealProof (abi.RegisteredSealProof) (int64)
-	{
-		maj, extra, err := cbg.CborReadHeaderBuf(br, scratch)
-		var extraI int64
-		if err != nil {
-			return err
-		}
-		switch maj {
-		case cbg.MajUnsignedInt:
-			extraI = int64(extra)
-			if extraI < 0 {
-				return fmt.Errorf("int64 positive overflow")
-			}
-		case cbg.MajNegativeInt:
-			extraI = int64(extra)
-			if extraI < 0 {
-				return fmt.Errorf("int64 negative oveflow")
-			}
-			extraI = -1 - extraI
-		default:
-			return fmt.Errorf("wrong type for int64 field: %d", maj)
-		}
-
-		t.SealProof = abi.RegisteredSealProof(extraI)
-	}
-	// t.SealedCID (cid.Cid) (struct)
-
-	{
-
-		c, err := cbg.ReadCid(br)
-		if err != nil {
-			return xerrors.Errorf("failed to read cid field t.SealedCID: %w", err)
-		}
-
-		t.SealedCID = c
-
-	}
-	// t.DealIDs ([]abi.DealID) (slice)
-
-	maj, extra, err = cbg.CborReadHeaderBuf(br, scratch)
-	if err != nil {
-		return err
-	}
-
-	if extra > cbg.MaxLength {
-		return fmt.Errorf("t.DealIDs: array too large (%d)", extra)
-	}
-
-	if maj != cbg.MajArray {
-		return fmt.Errorf("expected cbor array")
-	}
-
-	if extra > 0 {
-		t.DealIDs = make([]abi.DealID, extra)
-	}
-
-	for i := 0; i < int(extra); i++ {
-
-		maj, val, err := cbg.CborReadHeaderBuf(br, scratch)
-		if err != nil {
-			return xerrors.Errorf("failed to read uint64 for t.DealIDs slice: %w", err)
-		}
-
-		if maj != cbg.MajUnsignedInt {
-			return xerrors.Errorf("value read for array t.DealIDs was not a uint, instead got %d", maj)
-		}
-
-		t.DealIDs[i] = abi.DealID(val)
-	}
-
-	// t.Activation (abi.ChainEpoch) (int64)
-	{
-		maj, extra, err := cbg.CborReadHeaderBuf(br, scratch)
-		var extraI int64
-		if err != nil {
-			return err
-		}
-		switch maj {
-		case cbg.MajUnsignedInt:
-			extraI = int64(extra)
-			if extraI < 0 {
-				return fmt.Errorf("int64 positive overflow")
-			}
-		case cbg.MajNegativeInt:
-			extraI = int64(extra)
-			if extraI < 0 {
-				return fmt.Errorf("int64 negative oveflow")
-			}
-			extraI = -1 - extraI
-		default:
-			return fmt.Errorf("wrong type for int64 field: %d", maj)
-		}
-
-		t.Activation = abi.ChainEpoch(extraI)
-	}
-	// t.Expiration (abi.ChainEpoch) (int64)
-	{
-		maj, extra, err := cbg.CborReadHeaderBuf(br, scratch)
-		var extraI int64
-		if err != nil {
-			return err
-		}
-		switch maj {
-		case cbg.MajUnsignedInt:
-			extraI = int64(extra)
-			if extraI < 0 {
-				return fmt.Errorf("int64 positive overflow")
-			}
-		case cbg.MajNegativeInt:
-			extraI = int64(extra)
-			if extraI < 0 {
-				return fmt.Errorf("int64 negative oveflow")
-			}
-			extraI = -1 - extraI
-		default:
-			return fmt.Errorf("wrong type for int64 field: %d", maj)
-		}
-
-		t.Expiration = abi.ChainEpoch(extraI)
-	}
-	// t.DealWeight (big.Int) (struct)
-
-	{
-
-		if err := t.DealWeight.UnmarshalCBOR(br); err != nil {
-			return xerrors.Errorf("unmarshaling t.DealWeight: %w", err)
-		}
-
-	}
-	// t.VerifiedDealWeight (big.Int) (struct)
-
-	{
-
-		if err := t.VerifiedDealWeight.UnmarshalCBOR(br); err != nil {
-			return xerrors.Errorf("unmarshaling t.VerifiedDealWeight: %w", err)
-		}
-
-	}
-	// t.InitialPledge (big.Int) (struct)
-
-	{
-
-		if err := t.InitialPledge.UnmarshalCBOR(br); err != nil {
-			return xerrors.Errorf("unmarshaling t.InitialPledge: %w", err)
-		}
-
-	}
-	// t.ExpectedDayReward (big.Int) (struct)
-
-	{
-
-		if err := t.ExpectedDayReward.UnmarshalCBOR(br); err != nil {
-			return xerrors.Errorf("unmarshaling t.ExpectedDayReward: %w", err)
-		}
-
-	}
-	// t.ExpectedStoragePledge (big.Int) (struct)
-
-	{
-
-		if err := t.ExpectedStoragePledge.UnmarshalCBOR(br); err != nil {
-			return xerrors.Errorf("unmarshaling t.ExpectedStoragePledge: %w", err)
-		}
-
-	}
-	return nil
-}
@@ -0,0 +1,180 @@
+package miner
+
+import (
+	"errors"
+
+	"github.com/filecoin-project/go-bitfield"
+	"github.com/filecoin-project/go-state-types/exitcode"
+)
+
+type DeadlinesDiff map[uint64]*DeadlineDiff
+
+func DiffDeadlines(pre, cur State) (*DeadlinesDiff, error) {
+	changed, err := pre.DeadlinesChanged(cur)
+	if err != nil {
+		return nil, err
+	}
+	if !changed {
+		return nil, nil
+	}
+
+	numDl, err := pre.NumDeadlines()
+	if err != nil {
+		return nil, err
+	}
+	dlDiff := make(DeadlinesDiff, numDl)
+	if err := pre.ForEachDeadline(func(idx uint64, preDl Deadline) error {
+		curDl, err := cur.LoadDeadline(idx)
+		if err != nil {
+			return err
+		}
+
+		diff, err := DiffDeadline(preDl, curDl)
+		if err != nil {
+			return err
+		}
+
+		dlDiff[idx] = diff
+		return nil
+	}); err != nil {
+		return nil, err
+	}
+	return &dlDiff, nil
+}
+
+type DeadlineDiff map[uint64]*PartitionDiff
+
+func DiffDeadline(pre, cur Deadline) (*DeadlineDiff, error) {
+	changed, err := pre.PartitionsChanged(cur)
+	if err != nil {
+		return nil, err
+	}
+	if !changed {
+		return nil, nil
+	}
+
+	partDiff := make(DeadlineDiff)
+	if err := pre.ForEachPartition(func(idx uint64, prePart Partition) error {
+		// try loading current partition at this index
+		curPart, err := cur.LoadPartition(idx)
+		if err != nil {
+			if errors.Is(err, exitcode.ErrNotFound) {
+				// TODO correctness?
+				return nil // the partition was removed.
+			}
+			return err
+		}
+
+		// compare it with the previous partition
+		diff, err := DiffPartition(prePart, curPart)
+		if err != nil {
+			return err
+		}
+
+		partDiff[idx] = diff
+		return nil
+	}); err != nil {
+		return nil, err
+	}
+
+	// all previous partitions have been walked.
+	// all partitions in cur and not in prev are new... can they be faulty already?
+	// TODO is this correct?
+	if err := cur.ForEachPartition(func(idx uint64, curPart Partition) error {
+		if _, found := partDiff[idx]; found {
+			return nil
+		}
+		faults, err := curPart.FaultySectors()
+		if err != nil {
+			return err
+		}
+		recovering, err := curPart.RecoveringSectors()
+		if err != nil {
+			return err
+		}
+		partDiff[idx] = &PartitionDiff{
+			Removed:    bitfield.New(),
+			Recovered:  bitfield.New(),
+			Faulted:    faults,
+			Recovering: recovering,
+		}
+
+		return nil
+	}); err != nil {
+		return nil, err
+	}
+
+	return &partDiff, nil
+}
+
+type PartitionDiff struct {
+	Removed    bitfield.BitField
+	Recovered  bitfield.BitField
+	Faulted    bitfield.BitField
+	Recovering bitfield.BitField
+}
+
+func DiffPartition(pre, cur Partition) (*PartitionDiff, error) {
+	prevLiveSectors, err := pre.LiveSectors()
+	if err != nil {
+		return nil, err
+	}
+	curLiveSectors, err := cur.LiveSectors()
+	if err != nil {
+		return nil, err
+	}
+
+	removed, err := bitfield.SubtractBitField(prevLiveSectors, curLiveSectors)
+	if err != nil {
+		return nil, err
+	}
+
+	prevRecoveries, err := pre.RecoveringSectors()
+	if err != nil {
+		return nil, err
+	}
+
+	curRecoveries, err := cur.RecoveringSectors()
+	if err != nil {
+		return nil, err
+	}
+
+	recovering, err := bitfield.SubtractBitField(curRecoveries, prevRecoveries)
+	if err != nil {
+		return nil, err
+	}
+
+	prevFaults, err := pre.FaultySectors()
+	if err != nil {
+		return nil, err
+	}
+
+	curFaults, err := cur.FaultySectors()
+	if err != nil {
+		return nil, err
+	}
+
+	faulted, err := bitfield.SubtractBitField(curFaults, prevFaults)
+	if err != nil {
+		return nil, err
+	}
+
+	// all current good sectors
+	curActiveSectors, err := cur.ActiveSectors()
+	if err != nil {
+		return nil, err
+	}
+
+	// sectors that were previously fault and are now currently active are considered recovered.
+	recovered, err := bitfield.IntersectBitField(prevFaults, curActiveSectors)
+	if err != nil {
+		return nil, err
+	}
+
+	return &PartitionDiff{
+		Removed:    removed,
+		Recovered:  recovered,
+		Faulted:    faulted,
+		Recovering: recovering,
+	}, nil
+}
@@ -11,28 +11,40 @@ import (
 	"github.com/filecoin-project/go-state-types/abi"
 	"github.com/filecoin-project/go-state-types/cbor"
 	"github.com/filecoin-project/go-state-types/dline"
-	builtin0 "github.com/filecoin-project/specs-actors/actors/builtin"
-	miner0 "github.com/filecoin-project/specs-actors/actors/builtin/miner"

 	"github.com/filecoin-project/lotus/chain/actors/adt"
+	"github.com/filecoin-project/lotus/chain/actors/builtin"
 	"github.com/filecoin-project/lotus/chain/types"
+
+	builtin0 "github.com/filecoin-project/specs-actors/actors/builtin"
+	miner0 "github.com/filecoin-project/specs-actors/actors/builtin/miner"
+	builtin2 "github.com/filecoin-project/specs-actors/v2/actors/builtin"
 )

-// Unchanged between v0 and v1 actors
-var PreCommitChallengeDelay = miner0.PreCommitChallengeDelay
+func init() {
+	builtin.RegisterActorState(builtin0.StorageMinerActorCodeID, func(store adt.Store, root cid.Cid) (cbor.Marshaler, error) {
+		return load0(store, root)
+	})
+	builtin.RegisterActorState(builtin2.StorageMinerActorCodeID, func(store adt.Store, root cid.Cid) (cbor.Marshaler, error) {
+		return load2(store, root)
+	})
+}
+
+// Unchanged between v0 and v2 actors
 var WPoStProvingPeriod = miner0.WPoStProvingPeriod
+var WPoStPeriodDeadlines = miner0.WPoStPeriodDeadlines
+var WPoStChallengeWindow = miner0.WPoStChallengeWindow
+var WPoStChallengeLookback = miner0.WPoStChallengeLookback
+var FaultDeclarationCutoff = miner0.FaultDeclarationCutoff

 const MinSectorExpiration = miner0.MinSectorExpiration

 func Load(store adt.Store, act *types.Actor) (st State, err error) {
 	switch act.Code {
 	case builtin0.StorageMinerActorCodeID:
-		out := state0{store: store}
-		err := store.Get(store.Context(), act.Head, &out)
-		if err != nil {
-			return nil, err
-		}
-		return &out, nil
+		return load0(store, act.Head)
+	case builtin2.StorageMinerActorCodeID:
+		return load2(store, act.Head)
 	}
 	return nil, xerrors.Errorf("unknown actor code %s", act.Code)
 }
@@ -46,6 +58,7 @@ type State interface {
 	VestedFunds(abi.ChainEpoch) (abi.TokenAmount, error)
 	// Funds locked for various reasons.
 	LockedFunds() (LockedFunds, error)
+	FeeDebt() (abi.TokenAmount, error)

 	GetSector(abi.SectorNumber) (*SectorOnChainInfo, error)
 	FindSector(abi.SectorNumber) (*SectorLocation, error)
@@ -132,6 +145,7 @@ type MinerInfo struct {
 	SealProofType              abi.RegisteredSealProof
 	SectorSize                 abi.SectorSize
 	WindowPoStPartitionSectors uint64
+	ConsensusFaultElapsed      abi.ChainEpoch
 }

 type SectorExpiration struct {
@@ -4,21 +4,34 @@ import (
 	"bytes"
 	"errors"

-	"github.com/libp2p/go-libp2p-core/peer"
-	cbg "github.com/whyrusleeping/cbor-gen"
+	"github.com/filecoin-project/go-state-types/big"

 	"github.com/filecoin-project/go-address"
 	"github.com/filecoin-project/go-bitfield"
 	"github.com/filecoin-project/go-state-types/abi"
 	"github.com/filecoin-project/go-state-types/dline"
-	miner0 "github.com/filecoin-project/specs-actors/actors/builtin/miner"
-	adt0 "github.com/filecoin-project/specs-actors/actors/util/adt"
+	"github.com/ipfs/go-cid"
+	"github.com/libp2p/go-libp2p-core/peer"
+	cbg "github.com/whyrusleeping/cbor-gen"
+	"golang.org/x/xerrors"

 	"github.com/filecoin-project/lotus/chain/actors/adt"
+
+	miner0 "github.com/filecoin-project/specs-actors/actors/builtin/miner"
+	adt0 "github.com/filecoin-project/specs-actors/actors/util/adt"
 )

 var _ State = (*state0)(nil)

+func load0(store adt.Store, root cid.Cid) (State, error) {
+	out := state0{store: store}
+	err := store.Get(store.Context(), root, &out)
+	if err != nil {
+		return nil, err
+	}
+	return &out, nil
+}
+
 type state0 struct {
 	miner0.State
 	store adt.Store
@@ -50,6 +63,10 @@ func (s *state0) LockedFunds() (LockedFunds, error) {
 	}, nil
 }

+func (s *state0) FeeDebt() (abi.TokenAmount, error) {
+	return big.Zero(), nil
+}
+
 func (s *state0) InitialPledge() (abi.TokenAmount, error) {
 	return s.State.InitialPledgeRequirement, nil
 }
@@ -96,9 +113,7 @@ func (s *state0) NumLiveSectors() (uint64, error) {

 // GetSectorExpiration returns the effective expiration of the given sector.
 //
-// If the sector isn't found or has already been terminated, this method returns
-// nil and no error. If the sector does not expire early, the Early expiration
-// field is 0.
+// If the sector does not expire early, the Early expiration field is 0.
 func (s *state0) GetSectorExpiration(num abi.SectorNumber) (*SectorExpiration, error) {
 	dls, err := s.State.LoadDeadlines(s.store)
 	if err != nil {
@@ -161,7 +176,7 @@ func (s *state0) GetSectorExpiration(num abi.SectorNumber) (*SectorExpiration, e
 		return nil, err
 	}
 	if out.Early == 0 && out.OnTime == 0 {
-		return nil, nil
+		return nil, xerrors.Errorf("failed to find sector %d", num)
 	}
 	return &out, nil
 }
@@ -278,6 +293,7 @@ func (s *state0) Info() (MinerInfo, error) {
 		SealProofType:              info.SealProofType,
 		SectorSize:                 info.SectorSize,
 		WindowPoStPartitionSectors: info.WindowPoStPartitionSectors,
+		ConsensusFaultElapsed:      -1,
 	}

 	if info.PendingWorkerKey != nil {
@@ -0,0 +1,407 @@
+package miner
+
+import (
+	"bytes"
+	"errors"
+
+	"github.com/filecoin-project/go-address"
+	"github.com/filecoin-project/go-bitfield"
+	"github.com/filecoin-project/go-state-types/abi"
+	"github.com/filecoin-project/go-state-types/dline"
+	"github.com/ipfs/go-cid"
+	"github.com/libp2p/go-libp2p-core/peer"
+	cbg "github.com/whyrusleeping/cbor-gen"
+	"golang.org/x/xerrors"
+
+	"github.com/filecoin-project/lotus/chain/actors/adt"
+
+	miner2 "github.com/filecoin-project/specs-actors/v2/actors/builtin/miner"
+	adt2 "github.com/filecoin-project/specs-actors/v2/actors/util/adt"
+)
+
+var _ State = (*state2)(nil)
+
+func load2(store adt.Store, root cid.Cid) (State, error) {
+	out := state2{store: store}
+	err := store.Get(store.Context(), root, &out)
+	if err != nil {
+		return nil, err
+	}
+	return &out, nil
+}
+
+type state2 struct {
+	miner2.State
+	store adt.Store
+}
+
+type deadline2 struct {
+	miner2.Deadline
+	store adt.Store
+}
+
+type partition2 struct {
+	miner2.Partition
+	store adt.Store
+}
+
+func (s *state2) AvailableBalance(bal abi.TokenAmount) (abi.TokenAmount, error) {
+	return s.GetAvailableBalance(bal)
+}
+
+func (s *state2) VestedFunds(epoch abi.ChainEpoch) (abi.TokenAmount, error) {
+	return s.CheckVestedFunds(s.store, epoch)
+}
+
+func (s *state2) LockedFunds() (LockedFunds, error) {
+	return LockedFunds{
+		VestingFunds:             s.State.LockedFunds,
+		InitialPledgeRequirement: s.State.InitialPledge,
+		PreCommitDeposits:        s.State.PreCommitDeposits,
+	}, nil
+}
+
+func (s *state2) FeeDebt() (abi.TokenAmount, error) {
+	return s.State.FeeDebt, nil
+}
+
+func (s *state2) InitialPledge() (abi.TokenAmount, error) {
+	return s.State.InitialPledge, nil
+}
+
+func (s *state2) PreCommitDeposits() (abi.TokenAmount, error) {
+	return s.State.PreCommitDeposits, nil
+}
+
+func (s *state2) GetSector(num abi.SectorNumber) (*SectorOnChainInfo, error) {
+	info, ok, err := s.State.GetSector(s.store, num)
+	if !ok || err != nil {
+		return nil, err
+	}
+
+	ret := fromV2SectorOnChainInfo(*info)
+	return &ret, nil
+}
+
+func (s *state2) FindSector(num abi.SectorNumber) (*SectorLocation, error) {
+	dlIdx, partIdx, err := s.State.FindSector(s.store, num)
+	if err != nil {
+		return nil, err
+	}
+	return &SectorLocation{
+		Deadline:  dlIdx,
+		Partition: partIdx,
+	}, nil
+}
+
+func (s *state2) NumLiveSectors() (uint64, error) {
+	dls, err := s.State.LoadDeadlines(s.store)
+	if err != nil {
+		return 0, err
+	}
+	var total uint64
+	if err := dls.ForEach(s.store, func(dlIdx uint64, dl *miner2.Deadline) error {
+		total += dl.LiveSectors
+		return nil
+	}); err != nil {
+		return 0, err
+	}
+	return total, nil
+}
+
+// GetSectorExpiration returns the effective expiration of the given sector.
+//
+// If the sector does not expire early, the Early expiration field is 0.
+func (s *state2) GetSectorExpiration(num abi.SectorNumber) (*SectorExpiration, error) {
+	dls, err := s.State.LoadDeadlines(s.store)
+	if err != nil {
+		return nil, err
+	}
+	// NOTE: this can be optimized significantly.
+	// 1. If the sector is non-faulty, it will either expire on-time (can be
+	// learned from the sector info), or in the next quantized expiration
+	// epoch (i.e., the first element in the partition's expiration queue.
+	// 2. If it's faulty, it will expire early within the first 14 entries
+	// of the expiration queue.
+	stopErr := errors.New("stop")
+	out := SectorExpiration{}
+	err = dls.ForEach(s.store, func(dlIdx uint64, dl *miner2.Deadline) error {
+		partitions, err := dl.PartitionsArray(s.store)
+		if err != nil {
+			return err
+		}
+		quant := s.State.QuantSpecForDeadline(dlIdx)
+		var part miner2.Partition
+		return partitions.ForEach(&part, func(partIdx int64) error {
+			if found, err := part.Sectors.IsSet(uint64(num)); err != nil {
+				return err
+			} else if !found {
+				return nil
+			}
+			if found, err := part.Terminated.IsSet(uint64(num)); err != nil {
+				return err
+			} else if found {
+				// already terminated
+				return stopErr
+			}
+
+			q, err := miner2.LoadExpirationQueue(s.store, part.ExpirationsEpochs, quant)
+			if err != nil {
+				return err
+			}
+			var exp miner2.ExpirationSet
+			return q.ForEach(&exp, func(epoch int64) error {
+				if early, err := exp.EarlySectors.IsSet(uint64(num)); err != nil {
+					return err
+				} else if early {
+					out.Early = abi.ChainEpoch(epoch)
+					return nil
+				}
+				if onTime, err := exp.OnTimeSectors.IsSet(uint64(num)); err != nil {
+					return err
+				} else if onTime {
+					out.OnTime = abi.ChainEpoch(epoch)
+					return stopErr
+				}
+				return nil
+			})
+		})
+	})
+	if err == stopErr {
+		err = nil
+	}
+	if err != nil {
+		return nil, err
+	}
+	if out.Early == 0 && out.OnTime == 0 {
+		return nil, xerrors.Errorf("failed to find sector %d", num)
+	}
+	return &out, nil
+}
+
+func (s *state2) GetPrecommittedSector(num abi.SectorNumber) (*SectorPreCommitOnChainInfo, error) {
+	info, ok, err := s.State.GetPrecommittedSector(s.store, num)
+	if !ok || err != nil {
+		return nil, err
+	}
+
+	ret := fromV2SectorPreCommitOnChainInfo(*info)
+
+	return &ret, nil
+}
+
+func (s *state2) LoadSectors(snos *bitfield.BitField) ([]*SectorOnChainInfo, error) {
+	sectors, err := miner2.LoadSectors(s.store, s.State.Sectors)
+	if err != nil {
+		return nil, err
+	}
+
+	// If no sector numbers are specified, load all.
+	if snos == nil {
+		infos := make([]*SectorOnChainInfo, 0, sectors.Length())
+		var info2 miner2.SectorOnChainInfo
+		if err := sectors.ForEach(&info2, func(_ int64) error {
+			info := fromV2SectorOnChainInfo(info2)
+			infos = append(infos, &info)
+			return nil
+		}); err != nil {
+			return nil, err
+		}
+		return infos, nil
+	}
+
+	// Otherwise, load selected.
+	infos2, err := sectors.Load(*snos)
+	if err != nil {
+		return nil, err
+	}
+	infos := make([]*SectorOnChainInfo, len(infos2))
+	for i, info2 := range infos2 {
+		info := fromV2SectorOnChainInfo(*info2)
+		infos[i] = &info
+	}
+	return infos, nil
+}
+
+func (s *state2) IsAllocated(num abi.SectorNumber) (bool, error) {
+	var allocatedSectors bitfield.BitField
+	if err := s.store.Get(s.store.Context(), s.State.AllocatedSectors, &allocatedSectors); err != nil {
+		return false, err
+	}
+
+	return allocatedSectors.IsSet(uint64(num))
+}
+
+func (s *state2) LoadDeadline(idx uint64) (Deadline, error) {
+	dls, err := s.State.LoadDeadlines(s.store)
+	if err != nil {
+		return nil, err
+	}
+	dl, err := dls.LoadDeadline(s.store, idx)
+	if err != nil {
+		return nil, err
+	}
+	return &deadline2{*dl, s.store}, nil
+}
+
+func (s *state2) ForEachDeadline(cb func(uint64, Deadline) error) error {
+	dls, err := s.State.LoadDeadlines(s.store)
+	if err != nil {
+		return err
+	}
+	return dls.ForEach(s.store, func(i uint64, dl *miner2.Deadline) error {
+		return cb(i, &deadline2{*dl, s.store})
+	})
+}
+
+func (s *state2) NumDeadlines() (uint64, error) {
+	return miner2.WPoStPeriodDeadlines, nil
+}
+
+func (s *state2) DeadlinesChanged(other State) (bool, error) {
+	other2, ok := other.(*state2)
+	if !ok {
+		// treat an upgrade as a change, always
+		return true, nil
+	}
+
+	return s.State.Deadlines.Equals(other2.Deadlines), nil
+}
+
+func (s *state2) Info() (MinerInfo, error) {
+	info, err := s.State.GetInfo(s.store)
+	if err != nil {
+		return MinerInfo{}, err
+	}
+
+	var pid *peer.ID
+	if peerID, err := peer.IDFromBytes(info.PeerId); err == nil {
+		pid = &peerID
+	}
+
+	mi := MinerInfo{
+		Owner:            info.Owner,
+		Worker:           info.Worker,
+		ControlAddresses: info.ControlAddresses,
+
+		NewWorker:         address.Undef,
+		WorkerChangeEpoch: -1,
+
+		PeerId:                     pid,
+		Multiaddrs:                 info.Multiaddrs,
+		SealProofType:              info.SealProofType,
+		SectorSize:                 info.SectorSize,
+		WindowPoStPartitionSectors: info.WindowPoStPartitionSectors,
+		ConsensusFaultElapsed:      info.ConsensusFaultElapsed,
+	}
+
+	if info.PendingWorkerKey != nil {
+		mi.NewWorker = info.PendingWorkerKey.NewWorker
+		mi.WorkerChangeEpoch = info.PendingWorkerKey.EffectiveAt
+	}
+
+	return mi, nil
+}
+
+func (s *state2) DeadlineInfo(epoch abi.ChainEpoch) (*dline.Info, error) {
+	return s.State.DeadlineInfo(epoch), nil
+}
+
+func (s *state2) sectors() (adt.Array, error) {
+	return adt2.AsArray(s.store, s.Sectors)
+}
+
+func (s *state2) decodeSectorOnChainInfo(val *cbg.Deferred) (SectorOnChainInfo, error) {
+	var si miner2.SectorOnChainInfo
+	err := si.UnmarshalCBOR(bytes.NewReader(val.Raw))
+	if err != nil {
+		return SectorOnChainInfo{}, err
+	}
+
+	return fromV2SectorOnChainInfo(si), nil
+}
+
+func (s *state2) precommits() (adt.Map, error) {
+	return adt2.AsMap(s.store, s.PreCommittedSectors)
+}
+
+func (s *state2) decodeSectorPreCommitOnChainInfo(val *cbg.Deferred) (SectorPreCommitOnChainInfo, error) {
+	var sp miner2.SectorPreCommitOnChainInfo
+	err := sp.UnmarshalCBOR(bytes.NewReader(val.Raw))
+	if err != nil {
+		return SectorPreCommitOnChainInfo{}, err
+	}
+
+	return fromV2SectorPreCommitOnChainInfo(sp), nil
+}
+
+func (d *deadline2) LoadPartition(idx uint64) (Partition, error) {
+	p, err := d.Deadline.LoadPartition(d.store, idx)
+	if err != nil {
+		return nil, err
+	}
+	return &partition2{*p, d.store}, nil
+}
+
+func (d *deadline2) ForEachPartition(cb func(uint64, Partition) error) error {
+	ps, err := d.Deadline.PartitionsArray(d.store)
+	if err != nil {
+		return err
+	}
+	var part miner2.Partition
+	return ps.ForEach(&part, func(i int64) error {
+		return cb(uint64(i), &partition2{part, d.store})
+	})
+}
+
+func (d *deadline2) PartitionsChanged(other Deadline) (bool, error) {
+	other2, ok := other.(*deadline2)
+	if !ok {
+		// treat an upgrade as a change, always
+		return true, nil
+	}
+
+	return d.Deadline.Partitions.Equals(other2.Deadline.Partitions), nil
+}
+
+func (d *deadline2) PostSubmissions() (bitfield.BitField, error) {
+	return d.Deadline.PostSubmissions, nil
+}
+
+func (p *partition2) AllSectors() (bitfield.BitField, error) {
+	return p.Partition.Sectors, nil
+}
+
+func (p *partition2) FaultySectors() (bitfield.BitField, error) {
+	return p.Partition.Faults, nil
+}
+
+func (p *partition2) RecoveringSectors() (bitfield.BitField, error) {
+	return p.Partition.Recoveries, nil
+}
+
+func fromV2SectorOnChainInfo(v2 miner2.SectorOnChainInfo) SectorOnChainInfo {
+	return SectorOnChainInfo{
+		SectorNumber:          v2.SectorNumber,
+		SealProof:             v2.SealProof,
+		SealedCID:             v2.SealedCID,
+		DealIDs:               v2.DealIDs,
+		Activation:            v2.Activation,
+		Expiration:            v2.Expiration,
+		DealWeight:            v2.DealWeight,
+		VerifiedDealWeight:    v2.VerifiedDealWeight,
+		InitialPledge:         v2.InitialPledge,
+		ExpectedDayReward:     v2.ExpectedDayReward,
+		ExpectedStoragePledge: v2.ExpectedStoragePledge,
+	}
+}
+
+func fromV2SectorPreCommitOnChainInfo(v2 miner2.SectorPreCommitOnChainInfo) SectorPreCommitOnChainInfo {
+	return SectorPreCommitOnChainInfo{
+		Info:               (SectorPreCommitInfo)(v2.Info),
+		PreCommitDeposit:   v2.PreCommitDeposit,
+		PreCommitEpoch:     v2.PreCommitEpoch,
+		DealWeight:         v2.DealWeight,
+		VerifiedDealWeight: v2.VerifiedDealWeight,
+	}
+}
@@ -0,0 +1,70 @@
+package multisig
+
+import (
+	"fmt"
+
+	"github.com/minio/blake2b-simd"
+	"golang.org/x/xerrors"
+
+	"github.com/filecoin-project/go-address"
+	"github.com/filecoin-project/go-state-types/abi"
+
+	multisig2 "github.com/filecoin-project/specs-actors/v2/actors/builtin/multisig"
+
+	"github.com/filecoin-project/lotus/chain/actors"
+	"github.com/filecoin-project/lotus/chain/types"
+)
+
+func Message(version actors.Version, from address.Address) MessageBuilder {
+	switch version {
+	case actors.Version0:
+		return message0{from}
+	case actors.Version2:
+		return message2{message0{from}}
+	default:
+		panic(fmt.Sprintf("unsupported actors version: %d", version))
+	}
+}
+
+type MessageBuilder interface {
+	// Create a new multisig with the specified parameters.
+	Create(signers []address.Address, threshold uint64,
+		vestingStart, vestingDuration abi.ChainEpoch,
+		initialAmount abi.TokenAmount) (*types.Message, error)
+
+	// Propose a transaction to the given multisig.
+	Propose(msig, target address.Address, amt abi.TokenAmount,
+		method abi.MethodNum, params []byte) (*types.Message, error)
+
+	// Approve a multisig transaction. The "hash" is optional.
+	Approve(msig address.Address, txID uint64, hash *ProposalHashData) (*types.Message, error)
+
+	// Cancel a multisig transaction. The "hash" is optional.
+	Cancel(msig address.Address, txID uint64, hash *ProposalHashData) (*types.Message, error)
+}
+
+// this type is the same between v0 and v2
+type ProposalHashData = multisig2.ProposalHashData
+
+func txnParams(id uint64, data *ProposalHashData) ([]byte, error) {
+	params := multisig2.TxnIDParams{ID: multisig2.TxnID(id)}
+	if data != nil {
+		if data.Requester.Protocol() != address.ID {
+			return nil, xerrors.Errorf("proposer address must be an ID address, was %s", data.Requester)
+		}
+		if data.Value.Sign() == -1 {
+			return nil, xerrors.Errorf("proposal value must be non-negative, was %s", data.Value)
+		}
+		if data.To == address.Undef {
+			return nil, xerrors.Errorf("proposed destination address must be set")
+		}
+		pser, err := data.Serialize()
+		if err != nil {
+			return nil, err
+		}
+		hash := blake2b.Sum256(pser)
+		params.ProposalHash = hash[:]
+	}
+
+	return actors.SerializeParams(&params)
+}
@@ -0,0 +1,142 @@
+package multisig
+
+import (
+	"golang.org/x/xerrors"
+
+	"github.com/filecoin-project/go-address"
+	"github.com/filecoin-project/go-state-types/abi"
+
+	builtin0 "github.com/filecoin-project/specs-actors/actors/builtin"
+	init0 "github.com/filecoin-project/specs-actors/actors/builtin/init"
+	multisig0 "github.com/filecoin-project/specs-actors/actors/builtin/multisig"
+
+	"github.com/filecoin-project/lotus/chain/actors"
+	init_ "github.com/filecoin-project/lotus/chain/actors/builtin/init"
+	"github.com/filecoin-project/lotus/chain/types"
+)
+
+type message0 struct{ from address.Address }
+
+func (m message0) Create(
+	signers []address.Address, threshold uint64,
+	unlockStart, unlockDuration abi.ChainEpoch,
+	initialAmount abi.TokenAmount,
+) (*types.Message, error) {
+
+	lenAddrs := uint64(len(signers))
+
+	if lenAddrs < threshold {
+		return nil, xerrors.Errorf("cannot require signing of more addresses than provided for multisig")
+	}
+
+	if threshold == 0 {
+		threshold = lenAddrs
+	}
+
+	if m.from == address.Undef {
+		return nil, xerrors.Errorf("must provide source address")
+	}
+
+	if unlockStart != 0 {
+		return nil, xerrors.Errorf("actors v0 does not support a non-zero vesting start time")
+	}
+
+	// Set up constructor parameters for multisig
+	msigParams := &multisig0.ConstructorParams{
+		Signers:               signers,
+		NumApprovalsThreshold: threshold,
+		UnlockDuration:        unlockDuration,
+	}
+
+	enc, actErr := actors.SerializeParams(msigParams)
+	if actErr != nil {
+		return nil, actErr
+	}
+
+	// new actors are created by invoking 'exec' on the init actor with the constructor params
+	execParams := &init0.ExecParams{
+		CodeCID:           builtin0.MultisigActorCodeID,
+		ConstructorParams: enc,
+	}
+
+	enc, actErr = actors.SerializeParams(execParams)
+	if actErr != nil {
+		return nil, actErr
+	}
+
+	return &types.Message{
+		To:     init_.Address,
+		From:   m.from,
+		Method: builtin0.MethodsInit.Exec,
+		Params: enc,
+		Value:  initialAmount,
+	}, nil
+}
+
+func (m message0) Propose(msig, to address.Address, amt abi.TokenAmount,
+	method abi.MethodNum, params []byte) (*types.Message, error) {
+
+	if msig == address.Undef {
+		return nil, xerrors.Errorf("must provide a multisig address for proposal")
+	}
+
+	if to == address.Undef {
+		return nil, xerrors.Errorf("must provide a target address for proposal")
+	}
+
+	if amt.Sign() == -1 {
+		return nil, xerrors.Errorf("must provide a non-negative amount for proposed send")
+	}
+
+	if m.from == address.Undef {
+		return nil, xerrors.Errorf("must provide source address")
+	}
+
+	enc, actErr := actors.SerializeParams(&multisig0.ProposeParams{
+		To:     to,
+		Value:  amt,
+		Method: method,
+		Params: params,
+	})
+	if actErr != nil {
+		return nil, xerrors.Errorf("failed to serialize parameters: %w", actErr)
+	}
+
+	return &types.Message{
+		To:     msig,
+		From:   m.from,
+		Value:  abi.NewTokenAmount(0),
+		Method: builtin0.MethodsMultisig.Propose,
+		Params: enc,
+	}, nil
+}
+
+func (m message0) Approve(msig address.Address, txID uint64, hashData *ProposalHashData) (*types.Message, error) {
+	enc, err := txnParams(txID, hashData)
+	if err != nil {
+		return nil, err
+	}
+
+	return &types.Message{
+		To:     msig,
+		From:   m.from,
+		Value:  types.NewInt(0),
+		Method: builtin0.MethodsMultisig.Approve,
+		Params: enc,
+	}, nil
+}
+
+func (m message0) Cancel(msig address.Address, txID uint64, hashData *ProposalHashData) (*types.Message, error) {
+	enc, err := txnParams(txID, hashData)
+	if err != nil {
+		return nil, err
+	}
+
+	return &types.Message{
+		To:     msig,
+		From:   m.from,
+		Value:  types.NewInt(0),
+		Method: builtin0.MethodsMultisig.Cancel,
+		Params: enc,
+	}, nil
+}
@@ -0,0 +1,71 @@
+package multisig
+
+import (
+	"golang.org/x/xerrors"
+
+	"github.com/filecoin-project/go-address"
+	"github.com/filecoin-project/go-state-types/abi"
+
+	builtin2 "github.com/filecoin-project/specs-actors/v2/actors/builtin"
+	init2 "github.com/filecoin-project/specs-actors/v2/actors/builtin/init"
+	multisig2 "github.com/filecoin-project/specs-actors/v2/actors/builtin/multisig"
+
+	"github.com/filecoin-project/lotus/chain/actors"
+	init_ "github.com/filecoin-project/lotus/chain/actors/builtin/init"
+	"github.com/filecoin-project/lotus/chain/types"
+)
+
+type message2 struct{ message0 }
+
+func (m message2) Create(
+	signers []address.Address, threshold uint64,
+	unlockStart, unlockDuration abi.ChainEpoch,
+	initialAmount abi.TokenAmount,
+) (*types.Message, error) {
+
+	lenAddrs := uint64(len(signers))
+
+	if lenAddrs < threshold {
+		return nil, xerrors.Errorf("cannot require signing of more addresses than provided for multisig")
+	}
+
+	if threshold == 0 {
+		threshold = lenAddrs
+	}
+
+	if m.from == address.Undef {
+		return nil, xerrors.Errorf("must provide source address")
+	}
+
+	// Set up constructor parameters for multisig
+	msigParams := &multisig2.ConstructorParams{
+		Signers:               signers,
+		NumApprovalsThreshold: threshold,
+		UnlockDuration:        unlockDuration,
+		StartEpoch:            unlockStart,
+	}
+
+	enc, actErr := actors.SerializeParams(msigParams)
+	if actErr != nil {
+		return nil, actErr
+	}
+
+	// new actors are created by invoking 'exec' on the init actor with the constructor params
+	execParams := &init2.ExecParams{
+		CodeCID:           builtin2.MultisigActorCodeID,
+		ConstructorParams: enc,
+	}
+
+	enc, actErr = actors.SerializeParams(execParams)
+	if actErr != nil {
+		return nil, actErr
+	}
+
+	return &types.Message{
+		To:     init_.Address,
+		From:   m.from,
+		Method: builtin2.MethodsInit.Exec,
+		Params: enc,
+		Value:  initialAmount,
+	}, nil
+}
@@ -6,23 +6,32 @@ import (
 	"github.com/filecoin-project/go-address"
 	"github.com/filecoin-project/go-state-types/abi"
 	"github.com/filecoin-project/go-state-types/cbor"
+	"github.com/ipfs/go-cid"

 	builtin0 "github.com/filecoin-project/specs-actors/actors/builtin"
 	msig0 "github.com/filecoin-project/specs-actors/actors/builtin/multisig"
+	builtin2 "github.com/filecoin-project/specs-actors/v2/actors/builtin"

 	"github.com/filecoin-project/lotus/chain/actors/adt"
+	"github.com/filecoin-project/lotus/chain/actors/builtin"
 	"github.com/filecoin-project/lotus/chain/types"
 )

+func init() {
+	builtin.RegisterActorState(builtin0.MultisigActorCodeID, func(store adt.Store, root cid.Cid) (cbor.Marshaler, error) {
+		return load0(store, root)
+	})
+	builtin.RegisterActorState(builtin2.MultisigActorCodeID, func(store adt.Store, root cid.Cid) (cbor.Marshaler, error) {
+		return load2(store, root)
+	})
+}
+
 func Load(store adt.Store, act *types.Actor) (State, error) {
 	switch act.Code {
 	case builtin0.MultisigActorCodeID:
-		out := state0{store: store}
-		err := store.Get(store.Context(), act.Head, &out)
-		if err != nil {
-			return nil, err
-		}
-		return &out, nil
+		return load0(store, act.Head)
+	case builtin2.MultisigActorCodeID:
+		return load2(store, act.Head)
 	}
 	return nil, xerrors.Errorf("unknown actor code %s", act.Code)
 }
@@ -5,15 +5,26 @@ import (

 	"github.com/filecoin-project/go-address"
 	"github.com/filecoin-project/go-state-types/abi"
-	"github.com/filecoin-project/lotus/chain/actors/adt"
+	"github.com/ipfs/go-cid"
 	"golang.org/x/xerrors"

+	"github.com/filecoin-project/lotus/chain/actors/adt"
+
 	msig0 "github.com/filecoin-project/specs-actors/actors/builtin/multisig"
 	adt0 "github.com/filecoin-project/specs-actors/actors/util/adt"
 )

 var _ State = (*state0)(nil)

+func load0(store adt.Store, root cid.Cid) (State, error) {
+	out := state0{store: store}
+	err := store.Get(store.Context(), root, &out)
+	if err != nil {
+		return nil, err
+	}
+	return &out, nil
+}
+
 type state0 struct {
 	msig0.State
 	store adt.Store
@@ -0,0 +1,70 @@
+package multisig
+
+import (
+	"encoding/binary"
+
+	"github.com/filecoin-project/go-address"
+	"github.com/filecoin-project/go-state-types/abi"
+	"github.com/ipfs/go-cid"
+	"golang.org/x/xerrors"
+
+	"github.com/filecoin-project/lotus/chain/actors/adt"
+
+	msig2 "github.com/filecoin-project/specs-actors/v2/actors/builtin/multisig"
+	adt2 "github.com/filecoin-project/specs-actors/v2/actors/util/adt"
+)
+
+var _ State = (*state2)(nil)
+
+func load2(store adt.Store, root cid.Cid) (State, error) {
+	out := state2{store: store}
+	err := store.Get(store.Context(), root, &out)
+	if err != nil {
+		return nil, err
+	}
+	return &out, nil
+}
+
+type state2 struct {
+	msig2.State
+	store adt.Store
+}
+
+func (s *state2) LockedBalance(currEpoch abi.ChainEpoch) (abi.TokenAmount, error) {
+	return s.State.AmountLocked(currEpoch - s.State.StartEpoch), nil
+}
+
+func (s *state2) StartEpoch() (abi.ChainEpoch, error) {
+	return s.State.StartEpoch, nil
+}
+
+func (s *state2) UnlockDuration() (abi.ChainEpoch, error) {
+	return s.State.UnlockDuration, nil
+}
+
+func (s *state2) InitialBalance() (abi.TokenAmount, error) {
+	return s.State.InitialBalance, nil
+}
+
+func (s *state2) Threshold() (uint64, error) {
+	return s.State.NumApprovalsThreshold, nil
+}
+
+func (s *state2) Signers() ([]address.Address, error) {
+	return s.State.Signers, nil
+}
+
+func (s *state2) ForEachPendingTxn(cb func(id int64, txn Transaction) error) error {
+	arr, err := adt2.AsMap(s.store, s.State.PendingTxns)
+	if err != nil {
+		return err
+	}
+	var out msig2.Transaction
+	return arr.ForEach(&out, func(key string) error {
+		txid, n := binary.Varint([]byte(key))
+		if n <= 0 {
+			return xerrors.Errorf("invalid pending transaction key: %v", key)
+		}
+		return cb(txid, (Transaction)(out))
+	})
+}
@@ -0,0 +1,28 @@
+package paych
+
+import (
+	"fmt"
+
+	"github.com/filecoin-project/go-address"
+	"github.com/filecoin-project/go-state-types/abi"
+	"github.com/filecoin-project/lotus/chain/actors"
+	"github.com/filecoin-project/lotus/chain/types"
+)
+
+func Message(version actors.Version, from address.Address) MessageBuilder {
+	switch version {
+	case actors.Version0:
+		return message0{from}
+	case actors.Version2:
+		return message2{from}
+	default:
+		panic(fmt.Sprintf("unsupported actors version: %d", version))
+	}
+}
+
+type MessageBuilder interface {
+	Create(to address.Address, initialAmount abi.TokenAmount) (*types.Message, error)
+	Update(paych address.Address, voucher *SignedVoucher, secret []byte) (*types.Message, error)
+	Settle(paych address.Address) (*types.Message, error)
+	Collect(paych address.Address) (*types.Message, error)
+}
@@ -0,0 +1,74 @@
+package paych
+
+import (
+	"github.com/filecoin-project/go-address"
+	"github.com/filecoin-project/go-state-types/abi"
+
+	builtin0 "github.com/filecoin-project/specs-actors/actors/builtin"
+	init0 "github.com/filecoin-project/specs-actors/actors/builtin/init"
+	paych0 "github.com/filecoin-project/specs-actors/actors/builtin/paych"
+
+	"github.com/filecoin-project/lotus/chain/actors"
+	init_ "github.com/filecoin-project/lotus/chain/actors/builtin/init"
+	"github.com/filecoin-project/lotus/chain/types"
+)
+
+type message0 struct{ from address.Address }
+
+func (m message0) Create(to address.Address, initialAmount abi.TokenAmount) (*types.Message, error) {
+	params, aerr := actors.SerializeParams(&paych0.ConstructorParams{From: m.from, To: to})
+	if aerr != nil {
+		return nil, aerr
+	}
+	enc, aerr := actors.SerializeParams(&init0.ExecParams{
+		CodeCID:           builtin0.PaymentChannelActorCodeID,
+		ConstructorParams: params,
+	})
+	if aerr != nil {
+		return nil, aerr
+	}
+
+	return &types.Message{
+		To:     init_.Address,
+		From:   m.from,
+		Value:  initialAmount,
+		Method: builtin0.MethodsInit.Exec,
+		Params: enc,
+	}, nil
+}
+
+func (m message0) Update(paych address.Address, sv *SignedVoucher, secret []byte) (*types.Message, error) {
+	params, aerr := actors.SerializeParams(&paych0.UpdateChannelStateParams{
+		Sv:     *sv,
+		Secret: secret,
+	})
+	if aerr != nil {
+		return nil, aerr
+	}
+
+	return &types.Message{
+		To:     paych,
+		From:   m.from,
+		Value:  abi.NewTokenAmount(0),
+		Method: builtin0.MethodsPaych.UpdateChannelState,
+		Params: params,
+	}, nil
+}
+
+func (m message0) Settle(paych address.Address) (*types.Message, error) {
+	return &types.Message{
+		To:     paych,
+		From:   m.from,
+		Value:  abi.NewTokenAmount(0),
+		Method: builtin0.MethodsPaych.Settle,
+	}, nil
+}
+
+func (m message0) Collect(paych address.Address) (*types.Message, error) {
+	return &types.Message{
+		To:     paych,
+		From:   m.from,
+		Value:  abi.NewTokenAmount(0),
+		Method: builtin0.MethodsPaych.Collect,
+	}, nil
+}
@@ -0,0 +1,74 @@
+package paych
+
+import (
+	"github.com/filecoin-project/go-address"
+	"github.com/filecoin-project/go-state-types/abi"
+
+	builtin2 "github.com/filecoin-project/specs-actors/v2/actors/builtin"
+	init2 "github.com/filecoin-project/specs-actors/v2/actors/builtin/init"
+	paych2 "github.com/filecoin-project/specs-actors/v2/actors/builtin/paych"
+
+	"github.com/filecoin-project/lotus/chain/actors"
+	init_ "github.com/filecoin-project/lotus/chain/actors/builtin/init"
+	"github.com/filecoin-project/lotus/chain/types"
+)
+
+type message2 struct{ from address.Address }
+
+func (m message2) Create(to address.Address, initialAmount abi.TokenAmount) (*types.Message, error) {
+	params, aerr := actors.SerializeParams(&paych2.ConstructorParams{From: m.from, To: to})
+	if aerr != nil {
+		return nil, aerr
+	}
+	enc, aerr := actors.SerializeParams(&init2.ExecParams{
+		CodeCID:           builtin2.PaymentChannelActorCodeID,
+		ConstructorParams: params,
+	})
+	if aerr != nil {
+		return nil, aerr
+	}
+
+	return &types.Message{
+		To:     init_.Address,
+		From:   m.from,
+		Value:  initialAmount,
+		Method: builtin2.MethodsInit.Exec,
+		Params: enc,
+	}, nil
+}
+
+func (m message2) Update(paych address.Address, sv *SignedVoucher, secret []byte) (*types.Message, error) {
+	params, aerr := actors.SerializeParams(&paych2.UpdateChannelStateParams{
+		Sv:     *sv,
+		Secret: secret,
+	})
+	if aerr != nil {
+		return nil, aerr
+	}
+
+	return &types.Message{
+		To:     paych,
+		From:   m.from,
+		Value:  abi.NewTokenAmount(0),
+		Method: builtin2.MethodsPaych.UpdateChannelState,
+		Params: params,
+	}, nil
+}
+
+func (m message2) Settle(paych address.Address) (*types.Message, error) {
+	return &types.Message{
+		To:     paych,
+		From:   m.from,
+		Value:  abi.NewTokenAmount(0),
+		Method: builtin2.MethodsPaych.Settle,
+	}, nil
+}
+
+func (m message2) Collect(paych address.Address) (*types.Message, error) {
+	return &types.Message{
+		To:     paych,
+		From:   m.from,
+		Value:  abi.NewTokenAmount(0),
+		Method: builtin2.MethodsPaych.Collect,
+	}, nil
+}
@@ -27,10 +27,9 @@ type mockLaneState struct {
 func NewMockPayChState(from address.Address,
 	to address.Address,
 	settlingAt abi.ChainEpoch,
-	toSend abi.TokenAmount,
 	lanes map[uint64]paych.LaneState,
 ) paych.State {
-	return &mockState{from, to, settlingAt, toSend, lanes}
+	return &mockState{from: from, to: to, settlingAt: settlingAt, toSend: big.NewInt(0), lanes: lanes}
 }

 // NewMockLaneState constructs a state for a payment channel lane with the set fixed values
@@ -1,29 +1,42 @@
 package paych

 import (
+	"encoding/base64"
+
 	"golang.org/x/xerrors"

 	"github.com/filecoin-project/go-address"
 	"github.com/filecoin-project/go-state-types/abi"
 	big "github.com/filecoin-project/go-state-types/big"
 	"github.com/filecoin-project/go-state-types/cbor"
+	"github.com/ipfs/go-cid"
+	ipldcbor "github.com/ipfs/go-ipld-cbor"
+
 	builtin0 "github.com/filecoin-project/specs-actors/actors/builtin"
 	paych0 "github.com/filecoin-project/specs-actors/actors/builtin/paych"
+	builtin2 "github.com/filecoin-project/specs-actors/v2/actors/builtin"

 	"github.com/filecoin-project/lotus/chain/actors/adt"
+	"github.com/filecoin-project/lotus/chain/actors/builtin"
 	"github.com/filecoin-project/lotus/chain/types"
 )

+func init() {
+	builtin.RegisterActorState(builtin0.PaymentChannelActorCodeID, func(store adt.Store, root cid.Cid) (cbor.Marshaler, error) {
+		return load0(store, root)
+	})
+	builtin.RegisterActorState(builtin2.PaymentChannelActorCodeID, func(store adt.Store, root cid.Cid) (cbor.Marshaler, error) {
+		return load2(store, root)
+	})
+}
+
 // Load returns an abstract copy of payment channel state, irregardless of actor version
 func Load(store adt.Store, act *types.Actor) (State, error) {
 	switch act.Code {
 	case builtin0.PaymentChannelActorCodeID:
-		out := state0{store: store}
-		err := store.Get(store.Context(), act.Head, &out)
-		if err != nil {
-			return nil, err
-		}
-		return &out, nil
+		return load0(store, act.Head)
+	case builtin2.PaymentChannelActorCodeID:
+		return load2(store, act.Head)
 	}
 	return nil, xerrors.Errorf("unknown actor code %s", act.Code)
 }
@@ -58,3 +71,18 @@ type LaneState interface {

 type SignedVoucher = paych0.SignedVoucher
 type ModVerifyParams = paych0.ModVerifyParams
+
+// DecodeSignedVoucher decodes base64 encoded signed voucher.
+func DecodeSignedVoucher(s string) (*SignedVoucher, error) {
+	data, err := base64.RawURLEncoding.DecodeString(s)
+	if err != nil {
+		return nil, err
+	}
+
+	var sv SignedVoucher
+	if err := ipldcbor.DecodeInto(data, &sv); err != nil {
+		return nil, err
+	}
+
+	return &sv, nil
+}
@@ -1,18 +1,31 @@
 package paych

 import (
+	"github.com/ipfs/go-cid"
+
 	"github.com/filecoin-project/go-address"
 	"github.com/filecoin-project/go-state-types/abi"
-	big "github.com/filecoin-project/go-state-types/big"
+	"github.com/filecoin-project/go-state-types/big"
+
 	"github.com/filecoin-project/lotus/chain/actors/adt"
-	"github.com/filecoin-project/specs-actors/actors/builtin/paych"
+
+	paych0 "github.com/filecoin-project/specs-actors/actors/builtin/paych"
 	adt0 "github.com/filecoin-project/specs-actors/actors/util/adt"
 )

 var _ State = (*state0)(nil)

+func load0(store adt.Store, root cid.Cid) (State, error) {
+	out := state0{store: store}
+	err := store.Get(store.Context(), root, &out)
+	if err != nil {
+		return nil, err
+	}
+	return &out, nil
+}
+
 type state0 struct {
-	paych.State
+	paych0.State
 	store adt.Store
 	lsAmt *adt0.Array
 }
@@ -72,14 +85,14 @@ func (s *state0) ForEachLaneState(cb func(idx uint64, dl LaneState) error) error
 	// Note: we use a map instead of an array to store laneStates because the
 	// client sets the lane ID (the index) and potentially they could use a
 	// very large index.
-	var ls paych.LaneState
+	var ls paych0.LaneState
 	return lsamt.ForEach(&ls, func(i int64) error {
 		return cb(uint64(i), &laneState0{ls})
 	})
 }

 type laneState0 struct {
-	paych.LaneState
+	paych0.LaneState
 }

 func (ls *laneState0) Redeemed() (big.Int, error) {
@@ -0,0 +1,104 @@
+package paych
+
+import (
+	"github.com/ipfs/go-cid"
+
+	"github.com/filecoin-project/go-address"
+	"github.com/filecoin-project/go-state-types/abi"
+	"github.com/filecoin-project/go-state-types/big"
+
+	"github.com/filecoin-project/lotus/chain/actors/adt"
+
+	paych2 "github.com/filecoin-project/specs-actors/v2/actors/builtin/paych"
+	adt2 "github.com/filecoin-project/specs-actors/v2/actors/util/adt"
+)
+
+var _ State = (*state2)(nil)
+
+func load2(store adt.Store, root cid.Cid) (State, error) {
+	out := state2{store: store}
+	err := store.Get(store.Context(), root, &out)
+	if err != nil {
+		return nil, err
+	}
+	return &out, nil
+}
+
+type state2 struct {
+	paych2.State
+	store adt.Store
+	lsAmt *adt2.Array
+}
+
+// Channel owner, who has funded the actor
+func (s *state2) From() (address.Address, error) {
+	return s.State.From, nil
+}
+
+// Recipient of payouts from channel
+func (s *state2) To() (address.Address, error) {
+	return s.State.To, nil
+}
+
+// Height at which the channel can be `Collected`
+func (s *state2) SettlingAt() (abi.ChainEpoch, error) {
+	return s.State.SettlingAt, nil
+}
+
+// Amount successfully redeemed through the payment channel, paid out on `Collect()`
+func (s *state2) ToSend() (abi.TokenAmount, error) {
+	return s.State.ToSend, nil
+}
+
+func (s *state2) getOrLoadLsAmt() (*adt2.Array, error) {
+	if s.lsAmt != nil {
+		return s.lsAmt, nil
+	}
+
+	// Get the lane state from the chain
+	lsamt, err := adt2.AsArray(s.store, s.State.LaneStates)
+	if err != nil {
+		return nil, err
+	}
+
+	s.lsAmt = lsamt
+	return lsamt, nil
+}
+
+// Get total number of lanes
+func (s *state2) LaneCount() (uint64, error) {
+	lsamt, err := s.getOrLoadLsAmt()
+	if err != nil {
+		return 0, err
+	}
+	return lsamt.Length(), nil
+}
+
+// Iterate lane states
+func (s *state2) ForEachLaneState(cb func(idx uint64, dl LaneState) error) error {
+	// Get the lane state from the chain
+	lsamt, err := s.getOrLoadLsAmt()
+	if err != nil {
+		return err
+	}
+
+	// Note: we use a map instead of an array to store laneStates because the
+	// client sets the lane ID (the index) and potentially they could use a
+	// very large index.
+	var ls paych2.LaneState
+	return lsamt.ForEach(&ls, func(i int64) error {
+		return cb(uint64(i), &laneState2{ls})
+	})
+}
+
+type laneState2 struct {
+	paych2.LaneState
+}
+
+func (ls *laneState2) Redeemed() (big.Int, error) {
+	return ls.LaneState.Redeemed, nil
+}
+
+func (ls *laneState2) Nonce() (uint64, error) {
+	return ls.LaneState.Nonce, nil
+}
@@ -2,28 +2,37 @@ package power

 import (
 	"github.com/filecoin-project/go-address"
+	"github.com/ipfs/go-cid"
 	"golang.org/x/xerrors"

 	"github.com/filecoin-project/go-state-types/abi"
 	"github.com/filecoin-project/go-state-types/cbor"
-	builtin0 "github.com/filecoin-project/specs-actors/actors/builtin"

 	"github.com/filecoin-project/lotus/chain/actors/adt"
 	"github.com/filecoin-project/lotus/chain/actors/builtin"
 	"github.com/filecoin-project/lotus/chain/types"
+
+	builtin0 "github.com/filecoin-project/specs-actors/actors/builtin"
+	builtin2 "github.com/filecoin-project/specs-actors/v2/actors/builtin"
 )

+func init() {
+	builtin.RegisterActorState(builtin0.StoragePowerActorCodeID, func(store adt.Store, root cid.Cid) (cbor.Marshaler, error) {
+		return load0(store, root)
+	})
+	builtin.RegisterActorState(builtin2.StoragePowerActorCodeID, func(store adt.Store, root cid.Cid) (cbor.Marshaler, error) {
+		return load2(store, root)
+	})
+}
+
 var Address = builtin0.StoragePowerActorAddr

 func Load(store adt.Store, act *types.Actor) (st State, err error) {
 	switch act.Code {
 	case builtin0.StoragePowerActorCodeID:
-		out := state0{store: store}
-		err := store.Get(store.Context(), act.Head, &out)
-		if err != nil {
-			return nil, err
-		}
-		return &out, nil
+		return load0(store, act.Head)
+	case builtin2.StoragePowerActorCodeID:
+		return load2(store, act.Head)
 	}
 	return nil, xerrors.Errorf("unknown actor code %s", act.Code)
 }
@@ -3,13 +3,26 @@ package power
 import (
 	"github.com/filecoin-project/go-address"
 	"github.com/filecoin-project/go-state-types/abi"
+	"github.com/ipfs/go-cid"
+
+	"github.com/filecoin-project/lotus/chain/actors/adt"
 	"github.com/filecoin-project/lotus/chain/actors/builtin"
+
 	power0 "github.com/filecoin-project/specs-actors/actors/builtin/power"
-	"github.com/filecoin-project/specs-actors/actors/util/adt"
+	adt0 "github.com/filecoin-project/specs-actors/actors/util/adt"
 )

 var _ State = (*state0)(nil)

+func load0(store adt.Store, root cid.Cid) (State, error) {
+	out := state0{store: store}
+	err := store.Get(store.Context(), root, &out)
+	if err != nil {
+		return nil, err
+	}
+	return &out, nil
+}
+
 type state0 struct {
 	power0.State
 	store adt.Store
@@ -35,7 +48,7 @@ func (s *state0) TotalCommitted() (Claim, error) {
 }

 func (s *state0) MinerPower(addr address.Address) (Claim, bool, error) {
-	claims, err := adt.AsMap(s.store, s.Claims)
+	claims, err := adt0.AsMap(s.store, s.Claims)
 	if err != nil {
 		return Claim{}, false, err
 	}
@@ -63,7 +76,7 @@ func (s *state0) MinerCounts() (uint64, uint64, error) {
 }

 func (s *state0) ListAllMiners() ([]address.Address, error) {
-	claims, err := adt.AsMap(s.store, s.Claims)
+	claims, err := adt0.AsMap(s.store, s.Claims)
 	if err != nil {
 		return nil, err
 	}
@@ -0,0 +1,98 @@
+package power
+
+import (
+	"github.com/filecoin-project/go-address"
+	"github.com/filecoin-project/go-state-types/abi"
+	"github.com/ipfs/go-cid"
+
+	"github.com/filecoin-project/lotus/chain/actors/adt"
+	"github.com/filecoin-project/lotus/chain/actors/builtin"
+
+	power2 "github.com/filecoin-project/specs-actors/v2/actors/builtin/power"
+	adt2 "github.com/filecoin-project/specs-actors/v2/actors/util/adt"
+)
+
+var _ State = (*state2)(nil)
+
+func load2(store adt.Store, root cid.Cid) (State, error) {
+	out := state2{store: store}
+	err := store.Get(store.Context(), root, &out)
+	if err != nil {
+		return nil, err
+	}
+	return &out, nil
+}
+
+type state2 struct {
+	power2.State
+	store adt.Store
+}
+
+func (s *state2) TotalLocked() (abi.TokenAmount, error) {
+	return s.TotalPledgeCollateral, nil
+}
+
+func (s *state2) TotalPower() (Claim, error) {
+	return Claim{
+		RawBytePower:    s.TotalRawBytePower,
+		QualityAdjPower: s.TotalQualityAdjPower,
+	}, nil
+}
+
+// Committed power to the network. Includes miners below the minimum threshold.
+func (s *state2) TotalCommitted() (Claim, error) {
+	return Claim{
+		RawBytePower:    s.TotalBytesCommitted,
+		QualityAdjPower: s.TotalQABytesCommitted,
+	}, nil
+}
+
+func (s *state2) MinerPower(addr address.Address) (Claim, bool, error) {
+	claims, err := adt2.AsMap(s.store, s.Claims)
+	if err != nil {
+		return Claim{}, false, err
+	}
+	var claim power2.Claim
+	ok, err := claims.Get(abi.AddrKey(addr), &claim)
+	if err != nil {
+		return Claim{}, false, err
+	}
+	return Claim{
+		RawBytePower:    claim.RawBytePower,
+		QualityAdjPower: claim.QualityAdjPower,
+	}, ok, nil
+}
+
+func (s *state2) MinerNominalPowerMeetsConsensusMinimum(a address.Address) (bool, error) {
+	return s.State.MinerNominalPowerMeetsConsensusMinimum(s.store, a)
+}
+
+func (s *state2) TotalPowerSmoothed() (builtin.FilterEstimate, error) {
+	return builtin.FromV2FilterEstimate(s.State.ThisEpochQAPowerSmoothed), nil
+}
+
+func (s *state2) MinerCounts() (uint64, uint64, error) {
+	return uint64(s.State.MinerAboveMinPowerCount), uint64(s.State.MinerCount), nil
+}
+
+func (s *state2) ListAllMiners() ([]address.Address, error) {
+	claims, err := adt2.AsMap(s.store, s.Claims)
+	if err != nil {
+		return nil, err
+	}
+
+	var miners []address.Address
+	err = claims.ForEach(nil, func(k string) error {
+		a, err := address.NewFromBytes([]byte(k))
+		if err != nil {
+			return err
+		}
+		miners = append(miners, a)
+		return nil
+	})
+	if err != nil {
+		return nil, err
+	}
+
+	return miners, nil
+}
@@ -3,27 +3,35 @@ package reward
 import (
 	"github.com/filecoin-project/go-state-types/abi"
 	reward0 "github.com/filecoin-project/specs-actors/actors/builtin/reward"
+	"github.com/ipfs/go-cid"
 	"golang.org/x/xerrors"

 	"github.com/filecoin-project/go-state-types/cbor"
 	builtin0 "github.com/filecoin-project/specs-actors/actors/builtin"
+	builtin2 "github.com/filecoin-project/specs-actors/v2/actors/builtin"

 	"github.com/filecoin-project/lotus/chain/actors/adt"
 	"github.com/filecoin-project/lotus/chain/actors/builtin"
 	"github.com/filecoin-project/lotus/chain/types"
 )

+func init() {
+	builtin.RegisterActorState(builtin0.RewardActorCodeID, func(store adt.Store, root cid.Cid) (cbor.Marshaler, error) {
+		return load0(store, root)
+	})
+	builtin.RegisterActorState(builtin2.RewardActorCodeID, func(store adt.Store, root cid.Cid) (cbor.Marshaler, error) {
+		return load2(store, root)
+	})
+}
+
 var Address = builtin0.RewardActorAddr

 func Load(store adt.Store, act *types.Actor) (st State, err error) {
 	switch act.Code {
 	case builtin0.RewardActorCodeID:
-		out := state0{store: store}
-		err := store.Get(store.Context(), act.Head, &out)
-		if err != nil {
-			return nil, err
-		}
-		return &out, nil
+		return load0(store, act.Head)
+	case builtin2.RewardActorCodeID:
+		return load2(store, act.Head)
 	}
 	return nil, xerrors.Errorf("unknown actor code %s", act.Code)
 }
@@ -2,17 +2,29 @@ package reward

 import (
 	"github.com/filecoin-project/go-state-types/abi"
+	"github.com/ipfs/go-cid"
+
+	"github.com/filecoin-project/lotus/chain/actors/adt"
 	"github.com/filecoin-project/lotus/chain/actors/builtin"
+
 	miner0 "github.com/filecoin-project/specs-actors/actors/builtin/miner"
-	"github.com/filecoin-project/specs-actors/actors/builtin/reward"
-	"github.com/filecoin-project/specs-actors/actors/util/adt"
-	"github.com/filecoin-project/specs-actors/actors/util/smoothing"
+	reward0 "github.com/filecoin-project/specs-actors/actors/builtin/reward"
+	smoothing0 "github.com/filecoin-project/specs-actors/actors/util/smoothing"
 )

 var _ State = (*state0)(nil)

+func load0(store adt.Store, root cid.Cid) (State, error) {
+	out := state0{store: store}
+	err := store.Get(store.Context(), root, &out)
+	if err != nil {
+		return nil, err
+	}
+	return &out, nil
+}
+
 type state0 struct {
-	reward.State
+	reward0.State
 	store adt.Store
 }

@@ -54,7 +66,7 @@ func (s *state0) InitialPledgeForPower(sectorWeight abi.StoragePower, networkTot
 		s.State.ThisEpochBaselinePower,
 		networkTotalPledge,
 		s.State.ThisEpochRewardSmoothed,
-		&smoothing.FilterEstimate{
+		&smoothing0.FilterEstimate{
 			PositionEstimate: networkQAPower.PositionEstimate,
 			VelocityEstimate: networkQAPower.VelocityEstimate,
 		},
@@ -63,7 +75,7 @@ func (s *state0) InitialPledgeForPower(sectorWeight abi.StoragePower, networkTot

 func (s *state0) PreCommitDepositForPower(networkQAPower builtin.FilterEstimate, sectorWeight abi.StoragePower) (abi.TokenAmount, error) {
 	return miner0.PreCommitDepositForPower(s.State.ThisEpochRewardSmoothed,
-		&smoothing.FilterEstimate{
+		&smoothing0.FilterEstimate{
 			PositionEstimate: networkQAPower.PositionEstimate,
 			VelocityEstimate: networkQAPower.VelocityEstimate,
 		},
@@ -0,0 +1,86 @@
+package reward
+
+import (
+	"github.com/filecoin-project/go-state-types/abi"
+	"github.com/ipfs/go-cid"
+
+	"github.com/filecoin-project/lotus/chain/actors/adt"
+	"github.com/filecoin-project/lotus/chain/actors/builtin"
+
+	miner2 "github.com/filecoin-project/specs-actors/v2/actors/builtin/miner"
+	reward2 "github.com/filecoin-project/specs-actors/v2/actors/builtin/reward"
+	smoothing2 "github.com/filecoin-project/specs-actors/v2/actors/util/smoothing"
+)
+
+var _ State = (*state2)(nil)
+
+func load2(store adt.Store, root cid.Cid) (State, error) {
+	out := state2{store: store}
+	err := store.Get(store.Context(), root, &out)
+	if err != nil {
+		return nil, err
+	}
+	return &out, nil
+}
+
+type state2 struct {
+	reward2.State
+	store adt.Store
+}
+
+func (s *state2) ThisEpochReward() (abi.StoragePower, error) {
+	return s.State.ThisEpochReward, nil
+}
+
+func (s *state2) ThisEpochRewardSmoothed() (builtin.FilterEstimate, error) {
+	return builtin.FilterEstimate{
+		PositionEstimate: s.State.ThisEpochRewardSmoothed.PositionEstimate,
+		VelocityEstimate: s.State.ThisEpochRewardSmoothed.VelocityEstimate,
+	}, nil
+}
+
+func (s *state2) ThisEpochBaselinePower() (abi.StoragePower, error) {
+	return s.State.ThisEpochBaselinePower, nil
+}
+
+func (s *state2) TotalStoragePowerReward() (abi.TokenAmount, error) {
+	return s.State.TotalStoragePowerReward, nil
+}
+
+func (s *state2) EffectiveBaselinePower() (abi.StoragePower, error) {
+	return s.State.EffectiveBaselinePower, nil
+}
+
+func (s *state2) EffectiveNetworkTime() (abi.ChainEpoch, error) {
+	return s.State.EffectiveNetworkTime, nil
+}
+
+func (s *state2) CumsumBaseline() (abi.StoragePower, error) {
+	return s.State.CumsumBaseline, nil
+}
+
+func (s *state2) CumsumRealized() (abi.StoragePower, error) {
+	return s.State.CumsumBaseline, nil
+}
+
+func (s *state2) InitialPledgeForPower(qaPower abi.StoragePower, networkTotalPledge abi.TokenAmount, networkQAPower *builtin.FilterEstimate, circSupply abi.TokenAmount) (abi.TokenAmount, error) {
+	return miner2.InitialPledgeForPower(
+		qaPower,
+		s.State.ThisEpochBaselinePower,
+		s.State.ThisEpochRewardSmoothed,
+		smoothing2.FilterEstimate{
+			PositionEstimate: networkQAPower.PositionEstimate,
+			VelocityEstimate: networkQAPower.VelocityEstimate,
+		},
+		circSupply,
+	), nil
+}
+
+func (s *state2) PreCommitDepositForPower(networkQAPower builtin.FilterEstimate, sectorWeight abi.StoragePower) (abi.TokenAmount, error) {
+	return miner2.PreCommitDepositForPower(s.State.ThisEpochRewardSmoothed,
+		smoothing2.FilterEstimate{
+			PositionEstimate: networkQAPower.PositionEstimate,
+			VelocityEstimate: networkQAPower.VelocityEstimate,
+		},
+		sectorWeight), nil
+}
@@ -0,0 +1,46 @@
+package verifreg
+
+import (
+	"github.com/filecoin-project/go-address"
+	"github.com/filecoin-project/go-state-types/abi"
+	"github.com/filecoin-project/go-state-types/big"
+	"github.com/filecoin-project/lotus/chain/actors"
+	"github.com/filecoin-project/lotus/chain/actors/adt"
+	"github.com/ipfs/go-cid"
+	"golang.org/x/xerrors"
+)
+
+func getDataCap(store adt.Store, ver actors.Version, root cid.Cid, addr address.Address) (bool, abi.StoragePower, error) {
+	if addr.Protocol() != address.ID {
+		return false, big.Zero(), xerrors.Errorf("can only look up ID addresses")
+	}
+
+	vh, err := adt.AsMap(store, root, ver)
+	if err != nil {
+		return false, big.Zero(), xerrors.Errorf("loading verifreg: %w", err)
+	}
+
+	var dcap abi.StoragePower
+	if found, err := vh.Get(abi.AddrKey(addr), &dcap); err != nil {
+		return false, big.Zero(), xerrors.Errorf("looking up addr: %w", err)
+	} else if !found {
+		return false, big.Zero(), nil
+	}
+
+	return true, dcap, nil
+}
+
+func forEachCap(store adt.Store, ver actors.Version, root cid.Cid, cb func(addr address.Address, dcap abi.StoragePower) error) error {
+	vh, err := adt.AsMap(store, root, ver)
+	if err != nil {
+		return xerrors.Errorf("loading verified clients: %w", err)
+	}
+	var dcap abi.StoragePower
+	return vh.ForEach(&dcap, func(key string) error {
+		a, err := address.NewFromBytes([]byte(key))
+		if err != nil {
+			return err
+		}
+		return cb(a, dcap)
+	})
+}
@@ -3,69 +3,46 @@ package verifreg
 import (
 	"github.com/filecoin-project/go-address"
 	"github.com/filecoin-project/go-state-types/abi"
-	"github.com/filecoin-project/go-state-types/big"
-	verifreg0 "github.com/filecoin-project/specs-actors/actors/builtin/verifreg"
-	adt0 "github.com/filecoin-project/specs-actors/actors/util/adt"
 	"github.com/ipfs/go-cid"
-	"golang.org/x/xerrors"

+	"github.com/filecoin-project/lotus/chain/actors"
 	"github.com/filecoin-project/lotus/chain/actors/adt"
+
+	verifreg0 "github.com/filecoin-project/specs-actors/actors/builtin/verifreg"
 )

 var _ State = (*state0)(nil)

+func load0(store adt.Store, root cid.Cid) (State, error) {
+	out := state0{store: store}
+	err := store.Get(store.Context(), root, &out)
+	if err != nil {
+		return nil, err
+	}
+	return &out, nil
+}
+
 type state0 struct {
 	verifreg0.State
 	store adt.Store
 }

-func getDataCap(store adt.Store, root cid.Cid, addr address.Address) (bool, abi.StoragePower, error) {
-	if addr.Protocol() != address.ID {
-		return false, big.Zero(), xerrors.Errorf("can only look up ID addresses")
-	}
-
-	vh, err := adt0.AsMap(store, root)
-	if err != nil {
-		return false, big.Zero(), xerrors.Errorf("loading verifreg: %w", err)
-	}
-
-	var dcap abi.StoragePower
-	if found, err := vh.Get(abi.AddrKey(addr), &dcap); err != nil {
-		return false, big.Zero(), xerrors.Errorf("looking up addr: %w", err)
-	} else if !found {
-		return false, big.Zero(), nil
-	}
-
-	return true, dcap, nil
+func (s *state0) RootKey() (address.Address, error) {
+	return s.State.RootKey, nil
 }

 func (s *state0) VerifiedClientDataCap(addr address.Address) (bool, abi.StoragePower, error) {
-	return getDataCap(s.store, s.State.VerifiedClients, addr)
+	return getDataCap(s.store, actors.Version0, s.State.VerifiedClients, addr)
 }

 func (s *state0) VerifierDataCap(addr address.Address) (bool, abi.StoragePower, error) {
-	return getDataCap(s.store, s.State.Verifiers, addr)
-}
-
-func forEachCap(store adt.Store, root cid.Cid, cb func(addr address.Address, dcap abi.StoragePower) error) error {
-	vh, err := adt0.AsMap(store, root)
-	if err != nil {
-		return xerrors.Errorf("loading verified clients: %w", err)
-	}
-	var dcap abi.StoragePower
-	return vh.ForEach(&dcap, func(key string) error {
-		a, err := address.NewFromBytes([]byte(key))
-		if err != nil {
-			return err
-		}
-		return cb(a, dcap)
-	})
+	return getDataCap(s.store, actors.Version0, s.State.Verifiers, addr)
 }

 func (s *state0) ForEachVerifier(cb func(addr address.Address, dcap abi.StoragePower) error) error {
-	return forEachCap(s.store, s.State.Verifiers, cb)
+	return forEachCap(s.store, actors.Version0, s.State.Verifiers, cb)
 }

 func (s *state0) ForEachClient(cb func(addr address.Address, dcap abi.StoragePower) error) error {
-	return forEachCap(s.store, s.State.VerifiedClients, cb)
+	return forEachCap(s.store, actors.Version0, s.State.VerifiedClients, cb)
 }
@@ -0,0 +1,48 @@
+package verifreg
+
+import (
+	"github.com/filecoin-project/go-address"
+	"github.com/filecoin-project/go-state-types/abi"
+	"github.com/ipfs/go-cid"
+
+	"github.com/filecoin-project/lotus/chain/actors"
+	"github.com/filecoin-project/lotus/chain/actors/adt"
+
+	verifreg2 "github.com/filecoin-project/specs-actors/v2/actors/builtin/verifreg"
+)
+
+var _ State = (*state2)(nil)
+
+func load2(store adt.Store, root cid.Cid) (State, error) {
+	out := state2{store: store}
+	err := store.Get(store.Context(), root, &out)
+	if err != nil {
+		return nil, err
+	}
+	return &out, nil
+}
+
+type state2 struct {
+	verifreg2.State
+	store adt.Store
+}
+
+func (s *state2) RootKey() (address.Address, error) {
+	return s.State.RootKey, nil
+}
+
+func (s *state2) VerifiedClientDataCap(addr address.Address) (bool, abi.StoragePower, error) {
+	return getDataCap(s.store, actors.Version2, s.State.VerifiedClients, addr)
+}
+
+func (s *state2) VerifierDataCap(addr address.Address) (bool, abi.StoragePower, error) {
+	return getDataCap(s.store, actors.Version2, s.State.Verifiers, addr)
+}
+
+func (s *state2) ForEachVerifier(cb func(addr address.Address, dcap abi.StoragePower) error) error {
+	return forEachCap(s.store, actors.Version2, s.State.Verifiers, cb)
+}
+
+func (s *state2) ForEachClient(cb func(addr address.Address, dcap abi.StoragePower) error) error {
+	return forEachCap(s.store, actors.Version2, s.State.VerifiedClients, cb)
+}
@@ -3,26 +3,35 @@ package verifreg
 import (
 	"github.com/filecoin-project/go-address"
 	"github.com/filecoin-project/go-state-types/abi"
+	"github.com/ipfs/go-cid"
 	"golang.org/x/xerrors"

 	"github.com/filecoin-project/go-state-types/cbor"
 	builtin0 "github.com/filecoin-project/specs-actors/actors/builtin"
+	builtin2 "github.com/filecoin-project/specs-actors/v2/actors/builtin"

 	"github.com/filecoin-project/lotus/chain/actors/adt"
+	"github.com/filecoin-project/lotus/chain/actors/builtin"
 	"github.com/filecoin-project/lotus/chain/types"
 )

+func init() {
+	builtin.RegisterActorState(builtin0.VerifiedRegistryActorCodeID, func(store adt.Store, root cid.Cid) (cbor.Marshaler, error) {
+		return load0(store, root)
+	})
+	builtin.RegisterActorState(builtin2.VerifiedRegistryActorCodeID, func(store adt.Store, root cid.Cid) (cbor.Marshaler, error) {
+		return load2(store, root)
+	})
+}
+
 var Address = builtin0.VerifiedRegistryActorAddr

 func Load(store adt.Store, act *types.Actor) (State, error) {
 	switch act.Code {
 	case builtin0.VerifiedRegistryActorCodeID:
-		out := state0{store: store}
-		err := store.Get(store.Context(), act.Head, &out)
-		if err != nil {
-			return nil, err
-		}
-		return &out, nil
+		return load0(store, act.Head)
+	case builtin2.VerifiedRegistryActorCodeID:
+		return load2(store, act.Head)
 	}
 	return nil, xerrors.Errorf("unknown actor code %s", act.Code)
 }
@@ -30,6 +39,7 @@ func Load(store adt.Store, act *types.Actor) (State, error) {
 type State interface {
 	cbor.Marshaler

+	RootKey() (address.Address, error)
 	VerifiedClientDataCap(address.Address) (bool, abi.StoragePower, error)
 	VerifierDataCap(address.Address) (bool, abi.StoragePower, error)
 	ForEachVerifier(func(addr address.Address, dcap abi.StoragePower) error) error
@@ -0,0 +1,116 @@
+package policy
+
+import (
+	"github.com/filecoin-project/go-state-types/abi"
+	"github.com/filecoin-project/go-state-types/network"
+	"github.com/filecoin-project/lotus/chain/actors"
+	market0 "github.com/filecoin-project/specs-actors/actors/builtin/market"
+	miner0 "github.com/filecoin-project/specs-actors/actors/builtin/miner"
+	power0 "github.com/filecoin-project/specs-actors/actors/builtin/power"
+	verifreg0 "github.com/filecoin-project/specs-actors/actors/builtin/verifreg"
+	builtin2 "github.com/filecoin-project/specs-actors/v2/actors/builtin"
+	market2 "github.com/filecoin-project/specs-actors/v2/actors/builtin/market"
+	miner2 "github.com/filecoin-project/specs-actors/v2/actors/builtin/miner"
+	verifreg2 "github.com/filecoin-project/specs-actors/v2/actors/builtin/verifreg"
+)
+
+const (
+	ChainFinality          = miner0.ChainFinality
+	SealRandomnessLookback = ChainFinality
+)
+
+// SetSupportedProofTypes sets supported proof types, across all actor versions.
+// This should only be used for testing.
+func SetSupportedProofTypes(types ...abi.RegisteredSealProof) {
+	newTypes := make(map[abi.RegisteredSealProof]struct{}, len(types))
+	for _, t := range types {
+		newTypes[t] = struct{}{}
+	}
+	// Set for all miner versions.
+	miner0.SupportedProofTypes = newTypes
+	miner2.SupportedProofTypes = newTypes
+}
+
+// AddSupportedProofTypes sets supported proof types, across all actor versions.
+// This should only be used for testing.
+func AddSupportedProofTypes(types ...abi.RegisteredSealProof) {
+	for _, t := range types {
+		// Set for all miner versions.
+		miner0.SupportedProofTypes[t] = struct{}{}
+		miner2.SupportedProofTypes[t] = struct{}{}
+	}
+}
+
+// SetPreCommitChallengeDelay sets the pre-commit challenge delay across all
+// actors versions. Use for testing.
+func SetPreCommitChallengeDelay(delay abi.ChainEpoch) {
+	// Set for all miner versions.
+	miner0.PreCommitChallengeDelay = delay
+	miner2.PreCommitChallengeDelay = delay
+}
+
+// TODO: this function shouldn't really exist. Instead, the API should expose the precommit delay.
+func GetPreCommitChallengeDelay() abi.ChainEpoch {
+	return miner0.PreCommitChallengeDelay
+}
+
+// SetConsensusMinerMinPower sets the minimum power of an individual miner must
+// meet for leader election, across all actor versions. This should only be used
+// for testing.
+func SetConsensusMinerMinPower(p abi.StoragePower) {
+	power0.ConsensusMinerMinPower = p
+	for _, policy := range builtin2.SealProofPolicies {
+		policy.ConsensusMinerMinPower = p
+	}
+}
+
+// SetMinVerifiedDealSize sets the minimum size of a verified deal. This should
+// only be used for testing.
+func SetMinVerifiedDealSize(size abi.StoragePower) {
+	verifreg0.MinVerifiedDealSize = size
+	verifreg2.MinVerifiedDealSize = size
+}
+
+func GetMaxProveCommitDuration(ver actors.Version, t abi.RegisteredSealProof) abi.ChainEpoch {
+	switch ver {
+	case actors.Version0:
+		return miner0.MaxSealDuration[t]
+	case actors.Version2:
+		return miner2.MaxProveCommitDuration[t]
+	default:
+		panic("unsupported actors version")
+	}
+}
+
+func DealProviderCollateralBounds(
+	size abi.PaddedPieceSize, verified bool,
+	rawBytePower, qaPower, baselinePower abi.StoragePower,
+	circulatingFil abi.TokenAmount, nwVer network.Version,
+) (min, max abi.TokenAmount) {
+	switch actors.VersionForNetwork(nwVer) {
+	case actors.Version0:
+		return market0.DealProviderCollateralBounds(size, verified, rawBytePower, qaPower, baselinePower, circulatingFil, nwVer)
+	case actors.Version2:
+		return market2.DealProviderCollateralBounds(size, verified, rawBytePower, qaPower, baselinePower, circulatingFil)
+	default:
+		panic("unsupported network version")
+	}
+}
+
+// Sets the challenge window and scales the proving period to match (such that
+// there are always 48 challenge windows in a proving period).
+func SetWPoStChallengeWindow(period abi.ChainEpoch) {
+	miner0.WPoStChallengeWindow = period
+	miner0.WPoStProvingPeriod = period * abi.ChainEpoch(miner0.WPoStPeriodDeadlines)
+
+	miner2.WPoStChallengeWindow = period
+	miner2.WPoStProvingPeriod = period * abi.ChainEpoch(miner2.WPoStPeriodDeadlines)
+}
+
+func GetWinningPoStSectorSetLookback(nwVer network.Version) abi.ChainEpoch {
+	if nwVer <= network.Version3 {
+		return 10
+	}
+
+	return ChainFinality
+}
@@ -0,0 +1,50 @@
+package policy
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+
+	"github.com/filecoin-project/go-state-types/abi"
+	miner0 "github.com/filecoin-project/specs-actors/actors/builtin/miner"
+	verifreg0 "github.com/filecoin-project/specs-actors/actors/builtin/verifreg"
+	miner2 "github.com/filecoin-project/specs-actors/v2/actors/builtin/miner"
+	verifreg2 "github.com/filecoin-project/specs-actors/v2/actors/builtin/verifreg"
+)
+
+func TestSupportedProofTypes(t *testing.T) {
+	var oldTypes []abi.RegisteredSealProof
+	for t := range miner0.SupportedProofTypes {
+		oldTypes = append(oldTypes, t)
+	}
+	t.Cleanup(func() {
+		SetSupportedProofTypes(oldTypes...)
+	})
+
+	SetSupportedProofTypes(abi.RegisteredSealProof_StackedDrg2KiBV1)
+	require.EqualValues(t,
+		miner0.SupportedProofTypes,
+		map[abi.RegisteredSealProof]struct{}{
+			abi.RegisteredSealProof_StackedDrg2KiBV1: {},
+		},
+	)
+	AddSupportedProofTypes(abi.RegisteredSealProof_StackedDrg8MiBV1)
+	require.EqualValues(t,
+		miner0.SupportedProofTypes,
+		map[abi.RegisteredSealProof]struct{}{
+			abi.RegisteredSealProof_StackedDrg2KiBV1: {},
+			abi.RegisteredSealProof_StackedDrg8MiBV1: {},
+		},
+	)
+}
+
+// Tests assumptions about policies being the same between actor versions.
+func TestAssumptions(t *testing.T) {
+	require.EqualValues(t, miner0.SupportedProofTypes, miner2.SupportedProofTypes)
+	require.Equal(t, miner0.PreCommitChallengeDelay, miner2.PreCommitChallengeDelay)
+	require.Equal(t, miner0.ChainFinality, miner2.ChainFinality)
+	require.Equal(t, miner0.WPoStChallengeWindow, miner2.WPoStChallengeWindow)
+	require.Equal(t, miner0.WPoStProvingPeriod, miner2.WPoStProvingPeriod)
+	require.Equal(t, miner0.WPoStPeriodDeadlines, miner2.WPoStPeriodDeadlines)
+	require.True(t, verifreg0.MinVerifiedDealSize.Equals(verifreg2.MinVerifiedDealSize))
+}
@@ -0,0 +1,26 @@
+package actors
+
+import (
+	"fmt"
+
+	"github.com/filecoin-project/go-state-types/network"
+)
+
+type Version int
+
+const (
+	Version0 Version = 0
+	Version2 Version = 2
+)
+
+// Converts a network version into an actors adt version.
+func VersionForNetwork(version network.Version) Version {
+	switch version {
+	case network.Version0, network.Version1, network.Version2, network.Version3:
+		return Version0
+	case network.Version4:
+		return Version2
+	default:
+		panic(fmt.Sprintf("unsupported network version %d", version))
+	}
+}
@@ -581,7 +581,7 @@ func createEmptyMinerState(ctx context.Context, t *testing.T, store adt.Store, o
 func createSectorsAMT(ctx context.Context, t *testing.T, store adt.Store, sectors []miner.SectorOnChainInfo) cid.Cid {
 	root := adt.MakeEmptyArray(store)
 	for _, sector := range sectors {
-		sector := sector
+		sector := (miner0.SectorOnChainInfo)(sector)
 		err := root.Set(uint64(sector.SectorNumber), &sector)
 		require.NoError(t, err)
 	}
@@ -614,8 +614,8 @@ const (
 )

 // returns a unique SectorPreCommitInfo with each invocation with SectorNumber set to `sectorNo`.
-func newSectorPreCommitInfo(sectorNo abi.SectorNumber, sealed cid.Cid, expiration abi.ChainEpoch) *miner.SectorPreCommitInfo {
-	return &miner.SectorPreCommitInfo{
+func newSectorPreCommitInfo(sectorNo abi.SectorNumber, sealed cid.Cid, expiration abi.ChainEpoch) *miner0.SectorPreCommitInfo {
+	return &miner0.SectorPreCommitInfo{
 		SealProof:     abi.RegisteredSealProof_StackedDrg32GiBV1,
 		SectorNumber:  sectorNo,
 		SealedCID:     sealed,
@@ -117,7 +117,7 @@ func (c *client) doRequest(
 		res, err := c.sendRequestToPeer(ctx, peer, req)
 		if err != nil {
 			if !xerrors.Is(err, network.ErrNoConn) {
-				log.Warnf("could not connect to peer %s: %s",
+				log.Warnf("could not send request to peer %s: %s",
 					peer.String(), err)
 			}
 			continue
@@ -9,12 +9,12 @@ import (
 	"time"

 	"github.com/filecoin-project/specs-actors/actors/runtime/proof"
+	"github.com/google/uuid"

 	"github.com/filecoin-project/go-address"
 	"github.com/filecoin-project/go-state-types/abi"
 	"github.com/filecoin-project/go-state-types/big"
 	"github.com/filecoin-project/go-state-types/crypto"
-	miner0 "github.com/filecoin-project/specs-actors/actors/builtin/miner"
 	block "github.com/ipfs/go-block-format"
 	"github.com/ipfs/go-blockservice"
 	"github.com/ipfs/go-cid"
@@ -28,6 +28,7 @@ import (

 	"github.com/filecoin-project/lotus/api"
 	"github.com/filecoin-project/lotus/build"
+	"github.com/filecoin-project/lotus/chain/actors/policy"
 	"github.com/filecoin-project/lotus/chain/beacon"
 	genesis2 "github.com/filecoin-project/lotus/chain/gen/genesis"
 	"github.com/filecoin-project/lotus/chain/stmgr"
@@ -121,9 +122,8 @@ var DefaultRemainderAccountActor = genesis.Actor{
 }

 func NewGeneratorWithSectors(numSectors int) (*ChainGen, error) {
-	miner0.SupportedProofTypes = map[abi.RegisteredSealProof]struct{}{
-		abi.RegisteredSealProof_StackedDrg2KiBV1: {},
-	}
+	// TODO: we really shouldn't modify a global variable here.
+	policy.SetSupportedProofTypes(abi.RegisteredSealProof_StackedDrg2KiBV1)

 	mr := repo.NewMemory(nil)
 	lr, err := mr.Lock(repo.StorageMiner)
@@ -225,7 +225,7 @@ func NewGeneratorWithSectors(numSectors int) (*ChainGen, error) {
 		},
 		VerifregRootKey:  DefaultVerifregRootkeyActor,
 		RemainderAccount: DefaultRemainderAccountActor,
-		NetworkName:      "",
+		NetworkName:      uuid.New().String(),
 		Timestamp:        uint64(build.Clock.Now().Add(-500 * time.Duration(build.BlockDelaySecs) * time.Second).Unix()),
 	}

@@ -4,21 +4,16 @@ import (
 	"testing"

 	"github.com/filecoin-project/go-state-types/abi"
-	"github.com/filecoin-project/go-state-types/big"
-	miner0 "github.com/filecoin-project/specs-actors/actors/builtin/miner"
-	power0 "github.com/filecoin-project/specs-actors/actors/builtin/power"
-	verifreg0 "github.com/filecoin-project/specs-actors/actors/builtin/verifreg"

+	"github.com/filecoin-project/lotus/chain/actors/policy"
 	_ "github.com/filecoin-project/lotus/lib/sigs/bls"
 	_ "github.com/filecoin-project/lotus/lib/sigs/secp"
 )

 func init() {
-	miner0.SupportedProofTypes = map[abi.RegisteredSealProof]struct{}{
-		abi.RegisteredSealProof_StackedDrg2KiBV1: {},
-	}
-	power0.ConsensusMinerMinPower = big.NewInt(2048)
-	verifreg0.MinVerifiedDealSize = big.NewInt(256)
+	policy.SetSupportedProofTypes(abi.RegisteredSealProof_StackedDrg2KiBV1)
+	policy.SetConsensusMinerMinPower(abi.NewStoragePower(2048))
+	policy.SetMinVerifiedDealSize(abi.NewStoragePower(256))
 }

 func testGeneration(t testing.TB, n int, msgs int, sectors int) {
@@ -6,6 +6,8 @@ import (
 	"encoding/json"
 	"fmt"

+	"github.com/filecoin-project/lotus/chain/actors/builtin"
+
 	"github.com/ipfs/go-cid"
 	"github.com/ipfs/go-datastore"
 	cbor "github.com/ipfs/go-ipld-cbor"
@@ -24,7 +26,6 @@ import (
 	adt0 "github.com/filecoin-project/specs-actors/actors/util/adt"

 	"github.com/filecoin-project/lotus/build"
-	"github.com/filecoin-project/lotus/chain/actors/builtin"
 	"github.com/filecoin-project/lotus/chain/state"
 	"github.com/filecoin-project/lotus/chain/store"
 	"github.com/filecoin-project/lotus/chain/types"
@@ -115,7 +116,7 @@ func MakeInitialStateTree(ctx context.Context, bs bstore.Blockstore, template ge
 		return nil, nil, xerrors.Errorf("putting empty object: %w", err)
 	}

-	state, err := state.NewStateTree(cst, builtin.Version0)
+	state, err := state.NewStateTree(cst, types.StateTreeVersion0)
 	if err != nil {
 		return nil, nil, xerrors.Errorf("making new state tree: %w", err)
 	}
@@ -296,14 +297,9 @@ func MakeInitialStateTree(ctx context.Context, bs bstore.Blockstore, template ge
 		return nil, nil, xerrors.Errorf("somehow overallocated filecoin (allocated = %s)", types.FIL(totalFilAllocated))
 	}

-	remAccKey, err := address.NewIDAddress(90)
-	if err != nil {
-		return nil, nil, err
-	}
-
 	template.RemainderAccount.Balance = remainingFil

-	if err := createMultisigAccount(ctx, bs, cst, state, remAccKey, template.RemainderAccount, keyIDs); err != nil {
+	if err := createMultisigAccount(ctx, bs, cst, state, builtin.ReserveAddress, template.RemainderAccount, keyIDs); err != nil {
 		return nil, nil, xerrors.Errorf("failed to set up remainder account: %w", err)
 	}

@@ -105,6 +105,10 @@ func checkFault(t ds.Datastore, key ds.Key, bh *types.BlockHeader, faultType str
 			return err
 		}

+		if other == bh.Cid() {
+			return nil
+		}
+
 		return xerrors.Errorf("produced block would trigger '%s' consensus fault; miner: %s; bh: %s, other: %s", faultType, bh.Miner, bh.Cid(), other)
 	}

@@ -10,7 +10,9 @@ import (

 	"github.com/filecoin-project/go-address"
 	"github.com/filecoin-project/go-state-types/abi"
-	"github.com/filecoin-project/specs-actors/actors/builtin"
+
+	builtin0 "github.com/filecoin-project/specs-actors/actors/builtin"
+	builtin2 "github.com/filecoin-project/specs-actors/v2/actors/builtin"
 )

 type ActorLookup func(context.Context, address.Address, types.TipSetKey) (*types.Actor, error)
@@ -27,19 +29,33 @@ type CostKey struct {
 }

 var Costs = map[CostKey]int64{
-	{builtin.InitActorCodeID, 2}:          8916753,
-	{builtin.StorageMarketActorCodeID, 2}: 6955002,
-	{builtin.StorageMarketActorCodeID, 4}: 245436108,
-	{builtin.StorageMinerActorCodeID, 4}:  2315133,
-	{builtin.StorageMinerActorCodeID, 5}:  1600271356,
-	{builtin.StorageMinerActorCodeID, 6}:  22864493,
-	{builtin.StorageMinerActorCodeID, 7}:  142002419,
-	{builtin.StorageMinerActorCodeID, 10}: 23008274,
-	{builtin.StorageMinerActorCodeID, 11}: 19303178,
-	{builtin.StorageMinerActorCodeID, 14}: 566356835,
-	{builtin.StorageMinerActorCodeID, 16}: 5325185,
-	{builtin.StorageMinerActorCodeID, 18}: 2328637,
-	{builtin.StoragePowerActorCodeID, 2}:  23600956,
+	{builtin0.InitActorCodeID, 2}:          8916753,
+	{builtin0.StorageMarketActorCodeID, 2}: 6955002,
+	{builtin0.StorageMarketActorCodeID, 4}: 245436108,
+	{builtin0.StorageMinerActorCodeID, 4}:  2315133,
+	{builtin0.StorageMinerActorCodeID, 5}:  1600271356,
+	{builtin0.StorageMinerActorCodeID, 6}:  22864493,
+	{builtin0.StorageMinerActorCodeID, 7}:  142002419,
+	{builtin0.StorageMinerActorCodeID, 10}: 23008274,
+	{builtin0.StorageMinerActorCodeID, 11}: 19303178,
+	{builtin0.StorageMinerActorCodeID, 14}: 566356835,
+	{builtin0.StorageMinerActorCodeID, 16}: 5325185,
+	{builtin0.StorageMinerActorCodeID, 18}: 2328637,
+	{builtin0.StoragePowerActorCodeID, 2}:  23600956,
+	// TODO: Just reuse v0 values for now, this isn't actually used
+	{builtin2.InitActorCodeID, 2}:          8916753,
+	{builtin2.StorageMarketActorCodeID, 2}: 6955002,
+	{builtin2.StorageMarketActorCodeID, 4}: 245436108,
+	{builtin2.StorageMinerActorCodeID, 4}:  2315133,
+	{builtin2.StorageMinerActorCodeID, 5}:  1600271356,
+	{builtin2.StorageMinerActorCodeID, 6}:  22864493,
+	{builtin2.StorageMinerActorCodeID, 7}:  142002419,
+	{builtin2.StorageMinerActorCodeID, 10}: 23008274,
+	{builtin2.StorageMinerActorCodeID, 11}: 19303178,
+	{builtin2.StorageMinerActorCodeID, 14}: 566356835,
+	{builtin2.StorageMinerActorCodeID, 16}: 5325185,
+	{builtin2.StorageMinerActorCodeID, 18}: 2328637,
+	{builtin2.StoragePowerActorCodeID, 2}:  23600956,
 }

 func failedGuess(msg *types.SignedMessage) int64 {
@@ -51,7 +67,8 @@ func failedGuess(msg *types.SignedMessage) int64 {
 }

 func GuessGasUsed(ctx context.Context, tsk types.TipSetKey, msg *types.SignedMessage, al ActorLookup) (int64, error) {
-	if msg.Message.Method == builtin.MethodSend {
+	// MethodSend is the same in all versions.
+	if msg.Message.Method == builtin0.MethodSend {
 		switch msg.Message.From.Protocol() {
 		case address.BLS:
 			return 1298450, nil
@@ -55,6 +55,7 @@ var baseFeeLowerBoundFactor = types.NewInt(10)
 var baseFeeLowerBoundFactorConservative = types.NewInt(100)

 var MaxActorPendingMessages = 1000
+var MaxUntrustedActorPendingMessages = 10

 var MaxNonceGap = uint64(4)

@@ -75,8 +76,6 @@ var (
 	ErrRBFTooLowPremium       = errors.New("replace by fee has too low GasPremium")
 	ErrTooManyPendingMessages = errors.New("too many pending messages for actor")
 	ErrNonceGap               = errors.New("unfulfilled nonce gap")
-
-	ErrTryAgain = errors.New("state inconsistency while pushing message; please try again")
 )

 const (
@@ -197,9 +196,17 @@ func CapGasFee(msg *types.Message, maxFee abi.TokenAmount) {
 	msg.GasPremium = big.Min(msg.GasFeeCap, msg.GasPremium) // cap premium at FeeCap
 }

-func (ms *msgSet) add(m *types.SignedMessage, mp *MessagePool, strict bool) (bool, error) {
+func (ms *msgSet) add(m *types.SignedMessage, mp *MessagePool, strict, untrusted bool) (bool, error) {
 	nextNonce := ms.nextNonce
 	nonceGap := false
+
+	maxNonceGap := MaxNonceGap
+	maxActorPendingMessages := MaxActorPendingMessages
+	if untrusted {
+		maxNonceGap = 0
+		maxActorPendingMessages = MaxUntrustedActorPendingMessages
+	}
+
 	switch {
 	case m.Message.Nonce == nextNonce:
 		nextNonce++
@@ -208,7 +215,7 @@ func (ms *msgSet) add(m *types.SignedMessage, mp *MessagePool, strict bool) (boo
 			nextNonce++
 		}

-	case strict && m.Message.Nonce > nextNonce+MaxNonceGap:
+	case strict && m.Message.Nonce > nextNonce+maxNonceGap:
 		return false, xerrors.Errorf("message nonce has too big a gap from expected nonce (Nonce: %d, nextNonce: %d): %w", m.Message.Nonce, nextNonce, ErrNonceGap)

 	case m.Message.Nonce > nextNonce:
@@ -244,7 +251,7 @@ func (ms *msgSet) add(m *types.SignedMessage, mp *MessagePool, strict bool) (boo
 		//ms.requiredFunds.Sub(ms.requiredFunds, exms.Message.Value.Int)
 	}

-	if !has && strict && len(ms.msgs) > MaxActorPendingMessages {
+	if !has && strict && len(ms.msgs) >= maxActorPendingMessages {
 		log.Errorf("too many pending messages from actor %s", m.Message.From)
 		return false, ErrTooManyPendingMessages
 	}
@@ -486,7 +493,7 @@ func (mp *MessagePool) Push(m *types.SignedMessage) (cid.Cid, error) {
 	}

 	mp.curTsLk.Lock()
-	publish, err := mp.addTs(m, mp.curTs, true)
+	publish, err := mp.addTs(m, mp.curTs, true, false)
 	if err != nil {
 		mp.curTsLk.Unlock()
 		return cid.Undef, err
@@ -553,7 +560,7 @@ func (mp *MessagePool) Add(m *types.SignedMessage) error {
 	mp.curTsLk.Lock()
 	defer mp.curTsLk.Unlock()

-	_, err = mp.addTs(m, mp.curTs, false)
+	_, err = mp.addTs(m, mp.curTs, false, false)
 	return err
 }

@@ -621,7 +628,7 @@ func (mp *MessagePool) checkBalance(m *types.SignedMessage, curTs *types.TipSet)
 	return nil
 }

-func (mp *MessagePool) addTs(m *types.SignedMessage, curTs *types.TipSet, local bool) (bool, error) {
+func (mp *MessagePool) addTs(m *types.SignedMessage, curTs *types.TipSet, local, untrusted bool) (bool, error) {
 	snonce, err := mp.getStateNonce(m.Message.From, curTs)
 	if err != nil {
 		return false, xerrors.Errorf("failed to look up actor state nonce: %s: %w", err, ErrSoftValidationFailure)
@@ -643,7 +650,7 @@ func (mp *MessagePool) addTs(m *types.SignedMessage, curTs *types.TipSet, local
 		return false, err
 	}

-	return publish, mp.addLocked(m, !local)
+	return publish, mp.addLocked(m, !local, untrusted)
 }

 func (mp *MessagePool) addLoaded(m *types.SignedMessage) error {
@@ -678,17 +685,17 @@ func (mp *MessagePool) addLoaded(m *types.SignedMessage) error {
 		return err
 	}

-	return mp.addLocked(m, false)
+	return mp.addLocked(m, false, false)
 }

 func (mp *MessagePool) addSkipChecks(m *types.SignedMessage) error {
 	mp.lk.Lock()
 	defer mp.lk.Unlock()

-	return mp.addLocked(m, false)
+	return mp.addLocked(m, false, false)
 }

-func (mp *MessagePool) addLocked(m *types.SignedMessage, strict bool) error {
+func (mp *MessagePool) addLocked(m *types.SignedMessage, strict, untrusted bool) error {
 	log.Debugf("mpooladd: %s %d", m.Message.From, m.Message.Nonce)
 	if m.Signature.Type == crypto.SigTypeBLS {
 		mp.blsSigCache.Add(m.Cid(), m.Signature)
@@ -715,7 +722,7 @@ func (mp *MessagePool) addLocked(m *types.SignedMessage, strict bool) error {
 		mp.pending[m.Message.From] = mset
 	}

-	incr, err := mset.add(m, mp, strict)
+	incr, err := mset.add(m, mp, strict, untrusted)
 	if err != nil {
 		log.Debug(err)
 		return err
@@ -795,96 +802,48 @@ func (mp *MessagePool) getStateBalance(addr address.Address, ts *types.TipSet) (
 	return act.Balance, nil
 }

-func (mp *MessagePool) PushWithNonce(ctx context.Context, addr address.Address, cb func(address.Address, uint64) (*types.SignedMessage, error)) (*types.SignedMessage, error) {
+// this method is provided for the gateway to push messages.
+// differences from Push:
+//  - strict checks are enabled
+//  - extra strict add checks are used when adding the messages to the msgSet
+//    that means: no nonce gaps, at most 10 pending messages for the actor
+func (mp *MessagePool) PushUntrusted(m *types.SignedMessage) (cid.Cid, error) {
+	err := mp.checkMessage(m)
+	if err != nil {
+		return cid.Undef, err
+	}
+
 	// serialize push access to reduce lock contention
 	mp.addSema <- struct{}{}
 	defer func() {
 		<-mp.addSema
 	}()

-	mp.curTsLk.Lock()
-	mp.lk.Lock()
-
-	curTs := mp.curTs
-
-	fromKey := addr
-	if fromKey.Protocol() == address.ID {
-		var err error
-		fromKey, err = mp.api.StateAccountKey(ctx, fromKey, mp.curTs)
-		if err != nil {
-			mp.lk.Unlock()
-			mp.curTsLk.Unlock()
-			return nil, xerrors.Errorf("resolving sender key: %w", err)
-		}
-	}
-
-	nonce, err := mp.getNonceLocked(fromKey, mp.curTs)
+	msgb, err := m.Serialize()
 	if err != nil {
-		mp.lk.Unlock()
-		mp.curTsLk.Unlock()
-		return nil, xerrors.Errorf("get nonce locked failed: %w", err)
+		return cid.Undef, err
 	}

-	// release the locks for signing
-	mp.lk.Unlock()
+	mp.curTsLk.Lock()
+	publish, err := mp.addTs(m, mp.curTs, false, true)
+	if err != nil {
+		mp.curTsLk.Unlock()
+		return cid.Undef, err
+	}
 	mp.curTsLk.Unlock()

-	msg, err := cb(fromKey, nonce)
-	if err != nil {
-		return nil, err
-	}
-
-	err = mp.checkMessage(msg)
-	if err != nil {
-		return nil, err
-	}
-
-	msgb, err := msg.Serialize()
-	if err != nil {
-		return nil, err
-	}
-
-	// reacquire the locks and check state for consistency
-	mp.curTsLk.Lock()
-	defer mp.curTsLk.Unlock()
-
-	if mp.curTs != curTs {
-		return nil, ErrTryAgain
-	}
-
 	mp.lk.Lock()
-	defer mp.lk.Unlock()
-
-	nonce2, err := mp.getNonceLocked(fromKey, mp.curTs)
-	if err != nil {
-		return nil, xerrors.Errorf("get nonce locked failed: %w", err)
-	}
-
-	if nonce2 != nonce {
-		return nil, ErrTryAgain
-	}
-
-	publish, err := mp.verifyMsgBeforeAdd(msg, curTs, true)
-	if err != nil {
-		return nil, err
-	}
-
-	if err := mp.checkBalance(msg, curTs); err != nil {
-		return nil, err
-	}
-
-	if err := mp.addLocked(msg, false); err != nil {
-		return nil, xerrors.Errorf("add locked failed: %w", err)
-	}
-	if err := mp.addLocal(msg, msgb); err != nil {
-		log.Errorf("addLocal failed: %+v", err)
+	if err := mp.addLocal(m, msgb); err != nil {
+		mp.lk.Unlock()
+		return cid.Undef, err
 	}
+	mp.lk.Unlock()

 	if publish {
 		err = mp.api.PubSubPublish(build.MessagesTopic(mp.netName), msgb)
 	}

-	return msg, err
+	return m.Cid(), err
 }

 func (mp *MessagePool) Remove(from address.Address, nonce uint64, applied bool) {
@@ -0,0 +1,155 @@
+package messagesigner
+
+import (
+	"bytes"
+	"context"
+	"sync"
+
+	"github.com/filecoin-project/go-address"
+	"github.com/filecoin-project/lotus/chain/messagepool"
+	"github.com/filecoin-project/lotus/chain/types"
+	"github.com/filecoin-project/lotus/chain/wallet"
+	"github.com/filecoin-project/lotus/node/modules/dtypes"
+	"github.com/ipfs/go-datastore"
+	"github.com/ipfs/go-datastore/namespace"
+	logging "github.com/ipfs/go-log/v2"
+	cbg "github.com/whyrusleeping/cbor-gen"
+	"golang.org/x/xerrors"
+)
+
+const dsKeyActorNonce = "ActorNextNonce"
+
+var log = logging.Logger("messagesigner")
+
+type mpoolAPI interface {
+	GetNonce(address.Address) (uint64, error)
+}
+
+// MessageSigner keeps track of nonces per address, and increments the nonce
+// when signing a message
+type MessageSigner struct {
+	wallet *wallet.Wallet
+	lk     sync.Mutex
+	mpool  mpoolAPI
+	ds     datastore.Batching
+}
+
+func NewMessageSigner(wallet *wallet.Wallet, mpool *messagepool.MessagePool, ds dtypes.MetadataDS) *MessageSigner {
+	return newMessageSigner(wallet, mpool, ds)
+}
+
+func newMessageSigner(wallet *wallet.Wallet, mpool mpoolAPI, ds dtypes.MetadataDS) *MessageSigner {
+	ds = namespace.Wrap(ds, datastore.NewKey("/message-signer/"))
+	return &MessageSigner{
+		wallet: wallet,
+		mpool:  mpool,
+		ds:     ds,
+	}
+}
+
+// SignMessage increments the nonce for the message From address, and signs
+// the message
+func (ms *MessageSigner) SignMessage(ctx context.Context, msg *types.Message, cb func(*types.SignedMessage) error) (*types.SignedMessage, error) {
+	ms.lk.Lock()
+	defer ms.lk.Unlock()
+
+	// Get the next message nonce
+	nonce, err := ms.nextNonce(msg.From)
+	if err != nil {
+		return nil, xerrors.Errorf("failed to create nonce: %w", err)
+	}
+
+	// Sign the message with the nonce
+	msg.Nonce = nonce
+	sig, err := ms.wallet.Sign(ctx, msg.From, msg.Cid().Bytes())
+	if err != nil {
+		return nil, xerrors.Errorf("failed to sign message: %w", err)
+	}
+
+	// Callback with the signed message
+	smsg := &types.SignedMessage{
+		Message:   *msg,
+		Signature: *sig,
+	}
+	err = cb(smsg)
+	if err != nil {
+		return nil, err
+	}
+
+	// If the callback executed successfully, write the nonce to the datastore
+	if err := ms.saveNonce(msg.From, nonce); err != nil {
+		return nil, xerrors.Errorf("failed to save nonce: %w", err)
+	}
+
+	return smsg, nil
+}
+
+// nextNonce gets the next nonce for the given address.
+// If there is no nonce in the datastore, gets the nonce from the message pool.
+func (ms *MessageSigner) nextNonce(addr address.Address) (uint64, error) {
+	// Nonces used to be created by the mempool and we need to support nodes
+	// that have mempool nonces, so first check the mempool for a nonce for
+	// this address. Note that the mempool returns the actor state's nonce
+	// by default.
+	nonce, err := ms.mpool.GetNonce(addr)
+	if err != nil {
+		return 0, xerrors.Errorf("failed to get nonce from mempool: %w", err)
+	}
+
+	// Get the next nonce for this address from the datastore
+	addrNonceKey := ms.dstoreKey(addr)
+	dsNonceBytes, err := ms.ds.Get(addrNonceKey)
+
+	switch {
+	case xerrors.Is(err, datastore.ErrNotFound):
+		// If a nonce for this address hasn't yet been created in the
+		// datastore, just use the nonce from the mempool
+		return nonce, nil
+
+	case err != nil:
+		return 0, xerrors.Errorf("failed to get nonce from datastore: %w", err)
+
+	default:
+		// There is a nonce in the datastore, so unmarshall it
+		maj, dsNonce, err := cbg.CborReadHeader(bytes.NewReader(dsNonceBytes))
+		if err != nil {
+			return 0, xerrors.Errorf("failed to parse nonce from datastore: %w", err)
+		}
+		if maj != cbg.MajUnsignedInt {
+			return 0, xerrors.Errorf("bad cbor type parsing nonce from datastore")
+		}
+
+		// The message pool nonce should be <= than the datastore nonce
+		if nonce <= dsNonce {
+			nonce = dsNonce
+		} else {
+			log.Warnf("mempool nonce was larger than datastore nonce (%d > %d)", nonce, dsNonce)
+		}
+
+		return nonce, nil
+	}
+}
+
+// saveNonce increments the nonce for this address and writes it to the
+// datastore
+func (ms *MessageSigner) saveNonce(addr address.Address, nonce uint64) error {
+	// Increment the nonce
+	nonce++
+
+	// Write the nonce to the datastore
+	addrNonceKey := ms.dstoreKey(addr)
+	buf := bytes.Buffer{}
+	_, err := buf.Write(cbg.CborEncodeMajorType(cbg.MajUnsignedInt, nonce))
+	if err != nil {
+		return xerrors.Errorf("failed to marshall nonce: %w", err)
+	}
+	err = ms.ds.Put(addrNonceKey, buf.Bytes())
+	if err != nil {
+		return xerrors.Errorf("failed to write nonce to datastore: %w", err)
+	}
+	return nil
+}
+
+func (ms *MessageSigner) dstoreKey(addr address.Address) datastore.Key {
+	return datastore.KeyWithNamespaces([]string{dsKeyActorNonce, addr.String()})
+}
@@ -0,0 +1,201 @@
+package messagesigner
+
+import (
+	"context"
+	"sync"
+	"testing"
+
+	"golang.org/x/xerrors"
+
+	"github.com/filecoin-project/lotus/chain/wallet"
+
+	"github.com/filecoin-project/go-state-types/crypto"
+	"github.com/stretchr/testify/require"
+
+	ds_sync "github.com/ipfs/go-datastore/sync"
+
+	"github.com/filecoin-project/go-address"
+
+	"github.com/filecoin-project/lotus/chain/types"
+	"github.com/ipfs/go-datastore"
+)
+
+type mockMpool struct {
+	lk     sync.RWMutex
+	nonces map[address.Address]uint64
+}
+
+func newMockMpool() *mockMpool {
+	return &mockMpool{nonces: make(map[address.Address]uint64)}
+}
+
+func (mp *mockMpool) setNonce(addr address.Address, nonce uint64) {
+	mp.lk.Lock()
+	defer mp.lk.Unlock()
+
+	mp.nonces[addr] = nonce
+}
+
+func (mp *mockMpool) GetNonce(addr address.Address) (uint64, error) {
+	mp.lk.RLock()
+	defer mp.lk.RUnlock()
+
+	return mp.nonces[addr], nil
+}
+
+func TestMessageSignerSignMessage(t *testing.T) {
+	ctx := context.Background()
+
+	w, _ := wallet.NewWallet(wallet.NewMemKeyStore())
+	from1, err := w.GenerateKey(crypto.SigTypeSecp256k1)
+	require.NoError(t, err)
+	from2, err := w.GenerateKey(crypto.SigTypeSecp256k1)
+	require.NoError(t, err)
+	to1, err := w.GenerateKey(crypto.SigTypeSecp256k1)
+	require.NoError(t, err)
+	to2, err := w.GenerateKey(crypto.SigTypeSecp256k1)
+	require.NoError(t, err)
+
+	type msgSpec struct {
+		msg        *types.Message
+		mpoolNonce [1]uint64
+		expNonce   uint64
+		cbErr      error
+	}
+	tests := []struct {
+		name string
+		msgs []msgSpec
+	}{{
+		// No nonce yet in datastore
+		name: "no nonce yet",
+		msgs: []msgSpec{{
+			msg: &types.Message{
+				To:   to1,
+				From: from1,
+			},
+			expNonce: 0,
+		}},
+	}, {
+		// Get nonce value of zero from mpool
+		name: "mpool nonce zero",
+		msgs: []msgSpec{{
+			msg: &types.Message{
+				To:   to1,
+				From: from1,
+			},
+			mpoolNonce: [1]uint64{0},
+			expNonce:   0,
+		}},
+	}, {
+		// Get non-zero nonce value from mpool
+		name: "mpool nonce set",
+		msgs: []msgSpec{{
+			msg: &types.Message{
+				To:   to1,
+				From: from1,
+			},
+			mpoolNonce: [1]uint64{5},
+			expNonce:   5,
+		}, {
+			msg: &types.Message{
+				To:   to1,
+				From: from1,
+			},
+			// Should adjust datastore nonce because mpool nonce is higher
+			mpoolNonce: [1]uint64{10},
+			expNonce:   10,
+		}},
+	}, {
+		// Nonce should increment independently for each address
+		name: "nonce increments per address",
+		msgs: []msgSpec{{
+			msg: &types.Message{
+				To:   to1,
+				From: from1,
+			},
+			expNonce: 0,
+		}, {
+			msg: &types.Message{
+				To:   to1,
+				From: from1,
+			},
+			expNonce: 1,
+		}, {
+			msg: &types.Message{
+				To:   to2,
+				From: from2,
+			},
+			mpoolNonce: [1]uint64{5},
+			expNonce:   5,
+		}, {
+			msg: &types.Message{
+				To:   to2,
+				From: from2,
+			},
+			expNonce: 6,
+		}, {
+			msg: &types.Message{
+				To:   to1,
+				From: from1,
+			},
+			expNonce: 2,
+		}},
+	}, {
+		name: "recover from callback error",
+		msgs: []msgSpec{{
+			// No nonce yet in datastore
+			msg: &types.Message{
+				To:   to1,
+				From: from1,
+			},
+			expNonce: 0,
+		}, {
+			// Increment nonce
+			msg: &types.Message{
+				To:   to1,
+				From: from1,
+			},
+			expNonce: 1,
+		}, {
+			// Callback returns error
+			msg: &types.Message{
+				To:   to1,
+				From: from1,
+			},
+			cbErr: xerrors.Errorf("err"),
+		}, {
+			// Callback successful, should increment nonce in datastore
+			msg: &types.Message{
+				To:   to1,
+				From: from1,
+			},
+			expNonce: 2,
+		}},
+	}}
+	for _, tt := range tests {
+		tt := tt
+		t.Run(tt.name, func(t *testing.T) {
+			mpool := newMockMpool()
+			ds := ds_sync.MutexWrap(datastore.NewMapDatastore())
+			ms := newMessageSigner(w, mpool, ds)
+
+			for _, m := range tt.msgs {
+				if len(m.mpoolNonce) == 1 {
+					mpool.setNonce(m.msg.From, m.mpoolNonce[0])
+				}
+				merr := m.cbErr
+				smsg, err := ms.SignMessage(ctx, m.msg, func(message *types.SignedMessage) error {
+					return merr
+				})
+
+				if m.cbErr != nil {
+					require.Error(t, err)
+					require.Nil(t, smsg)
+				} else {
+					require.NoError(t, err)
+					require.Equal(t, m.expNonce, smsg.Message.Nonce)
+				}
+			}
+		})
+	}
+}
@@ -13,7 +13,8 @@ import (

 	"github.com/filecoin-project/go-address"
 	"github.com/filecoin-project/go-state-types/abi"
-	"github.com/filecoin-project/lotus/chain/actors/builtin"
+	"github.com/filecoin-project/go-state-types/network"
+	"github.com/filecoin-project/lotus/chain/actors"
 	init_ "github.com/filecoin-project/lotus/chain/actors/builtin/init"
 	cbg "github.com/whyrusleeping/cbor-gen"

@@ -26,7 +27,7 @@ var log = logging.Logger("statetree")
 // StateTree stores actors state by their ID.
 type StateTree struct {
 	root    adt.Map
-	version builtin.Version // TODO
+	version types.StateTreeVersion
 	info    cid.Cid
 	Store   cbor.IpldStore

@@ -120,15 +121,41 @@ func (ss *stateSnaps) deleteActor(addr address.Address) {
 	ss.layers[len(ss.layers)-1].actors[addr] = streeOp{Delete: true}
 }

-func NewStateTree(cst cbor.IpldStore, version builtin.Version) (*StateTree, error) {
-	var info cid.Cid
-	switch version {
-	case builtin.Version0:
-		// info is undefined
-	default:
-		return nil, xerrors.Errorf("unsupported state tree version: %d", version)
+// VersionForNetwork returns the state tree version for the given network
+// version.
+func VersionForNetwork(ver network.Version) types.StateTreeVersion {
+	if actors.VersionForNetwork(ver) == actors.Version0 {
+		return types.StateTreeVersion0
 	}
-	root, err := adt.NewMap(adt.WrapStore(context.TODO(), cst), version)
+	return types.StateTreeVersion1
+}
+
+func adtForSTVersion(ver types.StateTreeVersion) actors.Version {
+	switch ver {
+	case types.StateTreeVersion0:
+		return actors.Version0
+	case types.StateTreeVersion1:
+		return actors.Version2
+	default:
+		panic("unhandled state tree version")
+	}
+}
+
+func NewStateTree(cst cbor.IpldStore, ver types.StateTreeVersion) (*StateTree, error) {
+	var info cid.Cid
+	switch ver {
+	case types.StateTreeVersion0:
+		// info is undefined
+	case types.StateTreeVersion1:
+		var err error
+		info, err = cst.Put(context.TODO(), new(types.StateInfo0))
+		if err != nil {
+			return nil, err
+		}
+	default:
+		return nil, xerrors.Errorf("unsupported state tree version: %d", ver)
+	}
+	root, err := adt.NewMap(adt.WrapStore(context.TODO(), cst), adtForSTVersion(ver))
 	if err != nil {
 		return nil, err
 	}
@@ -136,7 +163,7 @@ func NewStateTree(cst cbor.IpldStore, version builtin.Version) (*StateTree, erro
 	return &StateTree{
 		root:    root,
 		info:    info,
-		version: version,
+		version: ver,
 		Store:   cst,
 		snaps:   newStateSnaps(),
 	}, nil
@@ -148,30 +175,31 @@ func LoadStateTree(cst cbor.IpldStore, c cid.Cid) (*StateTree, error) {
 	if err := cst.Get(context.TODO(), c, &root); err != nil {
 		// We failed to decode as the new version, must be an old version.
 		root.Actors = c
-		root.Version = builtin.Version0
-	}
-
-	// If that fails, load as an old-style state-tree (direct hampt, version 0.
-	nd, err := adt.AsMap(adt.WrapStore(context.TODO(), cst), root.Actors, builtin.Version(root.Version))
-	if err != nil {
-		log.Errorf("loading hamt node %s failed: %s", c, err)
-		return nil, err
+		root.Version = types.StateTreeVersion0
 	}

 	switch root.Version {
-	case builtin.Version0:
-		// supported
+	case types.StateTreeVersion0, types.StateTreeVersion1:
+		// Load the actual state-tree HAMT.
+		nd, err := adt.AsMap(
+			adt.WrapStore(context.TODO(), cst), root.Actors,
+			adtForSTVersion(root.Version),
+		)
+		if err != nil {
+			log.Errorf("loading hamt node %s failed: %s", c, err)
+			return nil, err
+		}
+
+		return &StateTree{
+			root:    nd,
+			info:    root.Info,
+			version: root.Version,
+			Store:   cst,
+			snaps:   newStateSnaps(),
+		}, nil
 	default:
 		return nil, xerrors.Errorf("unsupported state tree version: %d", root.Version)
 	}
-
-	return &StateTree{
-		root:    nd,
-		info:    root.Info,
-		version: builtin.Version(root.Version),
-		Store:   cst,
-		snaps:   newStateSnaps(),
-	}, nil
 }

 func (st *StateTree) SetActor(addr address.Address, act *types.Actor) error {
@@ -305,11 +333,11 @@ func (st *StateTree) Flush(ctx context.Context) (cid.Cid, error) {
 		return cid.Undef, xerrors.Errorf("failed to flush state-tree hamt: %w", err)
 	}
 	// If we're version 0, return a raw tree.
-	if st.version == builtin.Version0 {
+	if st.version == types.StateTreeVersion0 {
 		return root, nil
 	}
 	// Otherwise, return a versioned tree.
-	return st.Store.Put(ctx, &types.StateRoot{Version: uint64(st.version), Actors: root, Info: st.info})
+	return st.Store.Put(ctx, &types.StateRoot{Version: st.version, Actors: root, Info: st.info})
 }

 func (st *StateTree) Snapshot(ctx context.Context) error {
@@ -395,6 +423,11 @@ func (st *StateTree) ForEach(f func(address.Address, *types.Actor) error) error
 	})
 }

+// Version returns the version of the StateTree data structure in use.
+func (st *StateTree) Version() types.StateTreeVersion {
+	return st.version
+}
+
 func Diff(oldTree, newTree *StateTree) (map[string]types.Actor, error) {
 	out := map[string]types.Actor{}

@@ -9,16 +9,16 @@ import (
 	cbor "github.com/ipfs/go-ipld-cbor"

 	address "github.com/filecoin-project/go-address"
+	"github.com/filecoin-project/go-state-types/network"
 	"github.com/filecoin-project/specs-actors/actors/builtin"

 	"github.com/filecoin-project/lotus/build"
-	builtin2 "github.com/filecoin-project/lotus/chain/actors/builtin"
 	"github.com/filecoin-project/lotus/chain/types"
 )

 func BenchmarkStateTreeSet(b *testing.B) {
 	cst := cbor.NewMemCborStore()
-	st, err := NewStateTree(cst, builtin2.VersionForNetwork(build.NewestNetworkVersion))
+	st, err := NewStateTree(cst, VersionForNetwork(build.NewestNetworkVersion))
 	if err != nil {
 		b.Fatal(err)
 	}
@@ -45,7 +45,7 @@ func BenchmarkStateTreeSet(b *testing.B) {

 func BenchmarkStateTreeSetFlush(b *testing.B) {
 	cst := cbor.NewMemCborStore()
-	st, err := NewStateTree(cst, builtin2.VersionForNetwork(build.NewestNetworkVersion))
+	st, err := NewStateTree(cst, VersionForNetwork(build.NewestNetworkVersion))
 	if err != nil {
 		b.Fatal(err)
 	}
@@ -75,7 +75,7 @@ func BenchmarkStateTreeSetFlush(b *testing.B) {

 func BenchmarkStateTree10kGetActor(b *testing.B) {
 	cst := cbor.NewMemCborStore()
-	st, err := NewStateTree(cst, builtin2.VersionForNetwork(build.NewestNetworkVersion))
+	st, err := NewStateTree(cst, VersionForNetwork(build.NewestNetworkVersion))
 	if err != nil {
 		b.Fatal(err)
 	}
@@ -117,7 +117,7 @@ func BenchmarkStateTree10kGetActor(b *testing.B) {

 func TestSetCache(t *testing.T) {
 	cst := cbor.NewMemCborStore()
-	st, err := NewStateTree(cst, builtin2.VersionForNetwork(build.NewestNetworkVersion))
+	st, err := NewStateTree(cst, VersionForNetwork(build.NewestNetworkVersion))
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -154,7 +154,7 @@ func TestSetCache(t *testing.T) {
 func TestSnapshots(t *testing.T) {
 	ctx := context.Background()
 	cst := cbor.NewMemCborStore()
-	st, err := NewStateTree(cst, builtin2.VersionForNetwork(build.NewestNetworkVersion))
+	st, err := NewStateTree(cst, VersionForNetwork(build.NewestNetworkVersion))
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -237,7 +237,8 @@ func assertNotHas(t *testing.T, st *StateTree, addr address.Address) {

 func TestStateTreeConsistency(t *testing.T) {
 	cst := cbor.NewMemCborStore()
-	st, err := NewStateTree(cst, builtin2.VersionForNetwork(build.NewestNetworkVersion))
+	// TODO: ActorUpgrade: this test tests pre actors v2
+	st, err := NewStateTree(cst, VersionForNetwork(network.Version3))
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -2,10 +2,10 @@ package stmgr

 import (
 	"context"
+	"errors"
 	"fmt"

 	"github.com/filecoin-project/go-address"
-	"github.com/filecoin-project/go-state-types/abi"
 	"github.com/filecoin-project/go-state-types/crypto"
 	"github.com/ipfs/go-cid"
 	"go.opencensus.io/trace"
@@ -18,14 +18,47 @@ import (
 	"github.com/filecoin-project/lotus/chain/vm"
 )

-func (sm *StateManager) CallRaw(ctx context.Context, msg *types.Message, bstate cid.Cid, r vm.Rand, bheight abi.ChainEpoch) (*api.InvocResult, error) {
-	ctx, span := trace.StartSpan(ctx, "statemanager.CallRaw")
+var ErrExpensiveFork = errors.New("refusing explicit call due to state fork at epoch")
+
+func (sm *StateManager) Call(ctx context.Context, msg *types.Message, ts *types.TipSet) (*api.InvocResult, error) {
+	ctx, span := trace.StartSpan(ctx, "statemanager.Call")
 	defer span.End()

+	// If no tipset is provided, try to find one without a fork.
+	if ts == nil {
+		ts = sm.cs.GetHeaviestTipSet()
+
+		// Search back till we find a height with no fork, or we reach the beginning.
+		for ts.Height() > 0 && sm.hasExpensiveFork(ctx, ts.Height()-1) {
+			var err error
+			ts, err = sm.cs.GetTipSetFromKey(ts.Parents())
+			if err != nil {
+				return nil, xerrors.Errorf("failed to find a non-forking epoch: %w", err)
+			}
+		}
+	}
+
+	bstate := ts.ParentState()
+	bheight := ts.Height()
+
+	// If we have to run an expensive migration, and we're not at genesis,
+	// return an error because the migration will take too long.
+	//
+	// We allow this at height 0 for at-genesis migrations (for testing).
+	if bheight-1 > 0 && sm.hasExpensiveFork(ctx, bheight-1) {
+		return nil, ErrExpensiveFork
+	}
+
+	// Run the (not expensive) migration.
+	bstate, err := sm.handleStateForks(ctx, bstate, bheight-1, nil, ts)
+	if err != nil {
+		return nil, fmt.Errorf("failed to handle fork: %w", err)
+	}
+
 	vmopt := &vm.VMOpts{
 		StateBase:      bstate,
 		Epoch:          bheight,
-		Rand:           r,
+		Rand:           store.NewChainRand(sm.cs, ts.Cids()),
 		Bstore:         sm.cs.Blockstore(),
 		Syscalls:       sm.cs.VMSys(),
 		CircSupplyCalc: sm.GetCirculatingSupply,
@@ -33,7 +66,7 @@ func (sm *StateManager) CallRaw(ctx context.Context, msg *types.Message, bstate
 		BaseFee:        types.NewInt(0),
 	}

-	vmi, err := vm.NewVM(ctx, vmopt)
+	vmi, err := sm.newVM(ctx, vmopt)
 	if err != nil {
 		return nil, xerrors.Errorf("failed to set up vm: %w", err)
 	}
@@ -89,24 +122,30 @@ func (sm *StateManager) CallRaw(ctx context.Context, msg *types.Message, bstate

 }

-func (sm *StateManager) Call(ctx context.Context, msg *types.Message, ts *types.TipSet) (*api.InvocResult, error) {
-	if ts == nil {
-		ts = sm.cs.GetHeaviestTipSet()
-	}
-
-	state := ts.ParentState()
-
-	r := store.NewChainRand(sm.cs, ts.Cids())
-
-	return sm.CallRaw(ctx, msg, state, r, ts.Height())
-}
-
 func (sm *StateManager) CallWithGas(ctx context.Context, msg *types.Message, priorMsgs []types.ChainMsg, ts *types.TipSet) (*api.InvocResult, error) {
 	ctx, span := trace.StartSpan(ctx, "statemanager.CallWithGas")
 	defer span.End()

 	if ts == nil {
 		ts = sm.cs.GetHeaviestTipSet()
+
+		// Search back till we find a height with no fork, or we reach the beginning.
+		// We need the _previous_ height to have no fork, because we'll
+		// run the fork logic in `sm.TipSetState`. We need the _current_
+		// height to have no fork, because we'll run it inside this
+		// function before executing the given message.
+		for ts.Height() > 0 && (sm.hasExpensiveFork(ctx, ts.Height()) || sm.hasExpensiveFork(ctx, ts.Height()-1)) {
+			var err error
+			ts, err = sm.cs.GetTipSetFromKey(ts.Parents())
+			if err != nil {
+				return nil, xerrors.Errorf("failed to find a non-forking epoch: %w", err)
+			}
+		}
+	}
+
+	// When we're not at the genesis block, make sure we don't have an expensive migration.
+	if ts.Height() > 0 && (sm.hasExpensiveFork(ctx, ts.Height()) || sm.hasExpensiveFork(ctx, ts.Height()-1)) {
+		return nil, ErrExpensiveFork
 	}

 	state, _, err := sm.TipSetState(ctx, ts)
@@ -114,6 +153,11 @@ func (sm *StateManager) CallWithGas(ctx context.Context, msg *types.Message, pri
 		return nil, xerrors.Errorf("computing tipset state: %w", err)
 	}

+	state, err = sm.handleStateForks(ctx, state, ts.Height(), nil, ts)
+	if err != nil {
+		return nil, fmt.Errorf("failed to handle fork: %w", err)
+	}
+
 	r := store.NewChainRand(sm.cs, ts.Cids())

 	if span.IsRecordingEvents() {
@@ -134,7 +178,7 @@ func (sm *StateManager) CallWithGas(ctx context.Context, msg *types.Message, pri
 		NtwkVersion:    sm.GetNtwkVersion,
 		BaseFee:        ts.Blocks()[0].ParentBaseFee,
 	}
-	vmi, err := vm.NewVM(ctx, vmopt)
+	vmi, err := sm.newVM(ctx, vmopt)
 	if err != nil {
 		return nil, xerrors.Errorf("failed to set up vm: %w", err)
 	}
@@ -1,44 +1,172 @@
 package stmgr

 import (
+	"bytes"
 	"context"
+	"encoding/binary"
+	"math"
+
+	"github.com/filecoin-project/lotus/chain/actors/builtin"

 	"github.com/filecoin-project/go-address"
 	"github.com/filecoin-project/go-state-types/abi"
 	"github.com/filecoin-project/go-state-types/big"
+	"github.com/filecoin-project/go-state-types/network"
+	"github.com/ipfs/go-cid"
+	cbor "github.com/ipfs/go-ipld-cbor"
+	"golang.org/x/xerrors"

 	builtin0 "github.com/filecoin-project/specs-actors/actors/builtin"
 	miner0 "github.com/filecoin-project/specs-actors/actors/builtin/miner"
+	multisig0 "github.com/filecoin-project/specs-actors/actors/builtin/multisig"
 	power0 "github.com/filecoin-project/specs-actors/actors/builtin/power"
 	adt0 "github.com/filecoin-project/specs-actors/actors/util/adt"

+	"github.com/filecoin-project/specs-actors/actors/migration/nv3"
+	m2 "github.com/filecoin-project/specs-actors/v2/actors/migration"
+	states2 "github.com/filecoin-project/specs-actors/v2/actors/states"
+
 	"github.com/filecoin-project/lotus/build"
+	"github.com/filecoin-project/lotus/chain/actors/adt"
+	init_ "github.com/filecoin-project/lotus/chain/actors/builtin/init"
+	"github.com/filecoin-project/lotus/chain/actors/builtin/multisig"
+	"github.com/filecoin-project/lotus/chain/state"
+	"github.com/filecoin-project/lotus/chain/store"
 	"github.com/filecoin-project/lotus/chain/types"
-	cbor "github.com/ipfs/go-ipld-cbor"
-	"golang.org/x/xerrors"
+	"github.com/filecoin-project/lotus/chain/vm"
+	bstore "github.com/filecoin-project/lotus/lib/blockstore"
+	"github.com/filecoin-project/lotus/lib/bufbstore"
 )

-var ForksAtHeight = map[abi.ChainEpoch]func(context.Context, *StateManager, types.StateTree, *types.TipSet) error{
-	build.UpgradeBreezeHeight: UpgradeFaucetBurnRecovery,
+// UpgradeFunc is a migration function run at every upgrade.
+//
+// - The oldState is the state produced by the upgrade epoch.
+// - The returned newState is the new state that will be used by the next epoch.
+// - The height is the upgrade epoch height (already executed).
+// - The tipset is the tipset for the last non-null block before the upgrade. Do
+//   not assume that ts.Height() is the upgrade height.
+type UpgradeFunc func(ctx context.Context, sm *StateManager, cb ExecCallback, oldState cid.Cid, height abi.ChainEpoch, ts *types.TipSet) (newState cid.Cid, err error)
+
+type Upgrade struct {
+	Height    abi.ChainEpoch
+	Network   network.Version
+	Expensive bool
+	Migration UpgradeFunc
 }

-func (sm *StateManager) handleStateForks(ctx context.Context, st types.StateTree, height abi.ChainEpoch, ts *types.TipSet) (err error) {
-	f, ok := ForksAtHeight[height]
-	if ok {
-		err := f(ctx, sm, st, ts)
-		if err != nil {
-			return err
+type UpgradeSchedule []Upgrade
+
+func DefaultUpgradeSchedule() UpgradeSchedule {
+	var us UpgradeSchedule
+
+	updates := []Upgrade{{
+		Height:    build.UpgradeBreezeHeight,
+		Network:   network.Version1,
+		Migration: UpgradeFaucetBurnRecovery,
+	}, {
+		Height:    build.UpgradeSmokeHeight,
+		Network:   network.Version2,
+		Migration: nil,
+	}, {
+		Height:    build.UpgradeIgnitionHeight,
+		Network:   network.Version3,
+		Migration: UpgradeIgnition,
+	}, {
+		Height:    build.UpgradeRefuelHeight,
+		Network:   network.Version3,
+		Migration: UpgradeRefuel,
+	}, {
+		Height:    build.UpgradeActorsV2Height,
+		Network:   network.Version4,
+		Expensive: true,
+		Migration: UpgradeActorsV2,
+	}, {
+		Height:    build.UpgradeLiftoffHeight,
+		Network:   network.Version4,
+		Migration: UpgradeLiftoff,
+	}}
+
+	if build.UpgradeActorsV2Height == math.MaxInt64 { // disable actors upgrade
+		updates = []Upgrade{{
+			Height:    build.UpgradeBreezeHeight,
+			Network:   network.Version1,
+			Migration: UpgradeFaucetBurnRecovery,
+		}, {
+			Height:    build.UpgradeSmokeHeight,
+			Network:   network.Version2,
+			Migration: nil,
+		}, {
+			Height:    build.UpgradeIgnitionHeight,
+			Network:   network.Version3,
+			Migration: UpgradeIgnition,
+		}, {
+			Height:    build.UpgradeRefuelHeight,
+			Network:   network.Version3,
+			Migration: UpgradeRefuel,
+		}, {
+			Height:    build.UpgradeLiftoffHeight,
+			Network:   network.Version3,
+			Migration: UpgradeLiftoff,
+		}}
+	}
+
+	for _, u := range updates {
+		if u.Height < 0 {
+			// upgrade disabled
+			continue
+		}
+		us = append(us, u)
+	}
+	return us
+}
+
+func (us UpgradeSchedule) Validate() error {
+	// Make sure we're not trying to upgrade to version 0.
+	for _, u := range us {
+		if u.Network <= 0 {
+			return xerrors.Errorf("cannot upgrade to version <= 0: %d", u.Network)
 		}
 	}

+	// Make sure all the upgrades make sense.
+	for i := 1; i < len(us); i++ {
+		prev := &us[i-1]
+		curr := &us[i]
+		if !(prev.Network <= curr.Network) {
+			return xerrors.Errorf("cannot downgrade from version %d to version %d", prev.Network, curr.Network)
+		}
+		// Make sure the heights make sense.
+		if prev.Height < 0 {
+			// Previous upgrade was disabled.
+			continue
+		}
+		if !(prev.Height < curr.Height) {
+			return xerrors.Errorf("upgrade heights must be strictly increasing: upgrade %d was at height %d, followed by upgrade %d at height %d", i-1, prev.Height, i, curr.Height)
+		}
+	}
 	return nil
 }

-type forEachTree interface {
-	ForEach(func(address.Address, *types.Actor) error) error
+func (sm *StateManager) handleStateForks(ctx context.Context, root cid.Cid, height abi.ChainEpoch, cb ExecCallback, ts *types.TipSet) (cid.Cid, error) {
+	retCid := root
+	var err error
+	f, ok := sm.stateMigrations[height]
+	if ok {
+		retCid, err = f(ctx, sm, cb, root, height, ts)
+		if err != nil {
+			return cid.Undef, err
+		}
+	}
+
+	return retCid, nil
 }

-func doTransfer(tree types.StateTree, from, to address.Address, amt abi.TokenAmount) error {
+func (sm *StateManager) hasExpensiveFork(ctx context.Context, height abi.ChainEpoch) bool {
+	_, ok := sm.expensiveUpgrades[height]
+	return ok
+}
+
+func doTransfer(cb ExecCallback, tree types.StateTree, from, to address.Address, amt abi.TokenAmount) error {
 	fromAct, err := tree.GetActor(from)
 	if err != nil {
 		return xerrors.Errorf("failed to get 'from' actor for transfer: %w", err)
@@ -64,10 +192,43 @@ func doTransfer(tree types.StateTree, from, to address.Address, amt abi.TokenAmo
 		return xerrors.Errorf("failed to persist to actor: %w", err)
 	}

+	if cb != nil {
+		// record the transfer in execution traces
+
+		fakeMsg := &types.Message{
+			From:  from,
+			To:    to,
+			Value: amt,
+			Nonce: math.MaxUint64,
+		}
+		fakeRct := &types.MessageReceipt{
+			ExitCode: 0,
+			Return:   nil,
+			GasUsed:  0,
+		}
+
+		if err := cb(fakeMsg.Cid(), fakeMsg, &vm.ApplyRet{
+			MessageReceipt: *fakeRct,
+			ActorErr:       nil,
+			ExecutionTrace: types.ExecutionTrace{
+				Msg:        fakeMsg,
+				MsgRct:     fakeRct,
+				Error:      "",
+				Duration:   0,
+				GasCharges: nil,
+				Subcalls:   nil,
+			},
+			Duration: 0,
+			GasCosts: vm.ZeroGasOutputs(),
+		}); err != nil {
+			return xerrors.Errorf("recording transfer: %w", err)
+		}
+	}
+
 	return nil
 }

-func UpgradeFaucetBurnRecovery(ctx context.Context, sm *StateManager, tree types.StateTree, ts *types.TipSet) error {
+func UpgradeFaucetBurnRecovery(ctx context.Context, sm *StateManager, cb ExecCallback, root cid.Cid, epoch abi.ChainEpoch, ts *types.TipSet) (cid.Cid, error) {
 	// Some initial parameters
 	FundsForMiners := types.FromFil(1_000_000)
 	LookbackEpoch := abi.ChainEpoch(32000)
@@ -94,22 +255,22 @@ func UpgradeFaucetBurnRecovery(ctx context.Context, sm *StateManager, tree types
 	// Grab lookback state for account checks
 	lbts, err := sm.ChainStore().GetTipsetByHeight(ctx, LookbackEpoch, ts, false)
 	if err != nil {
-		return xerrors.Errorf("failed to get tipset at lookback height: %w", err)
+		return cid.Undef, xerrors.Errorf("failed to get tipset at lookback height: %w", err)
 	}

 	lbtree, err := sm.ParentState(lbts)
 	if err != nil {
-		return xerrors.Errorf("loading state tree failed: %w", err)
+		return cid.Undef, xerrors.Errorf("loading state tree failed: %w", err)
 	}

 	ReserveAddress, err := address.NewFromString("t090")
 	if err != nil {
-		return xerrors.Errorf("failed to parse reserve address: %w", err)
+		return cid.Undef, xerrors.Errorf("failed to parse reserve address: %w", err)
 	}

-	fetree, ok := tree.(forEachTree)
-	if !ok {
-		return xerrors.Errorf("fork transition state tree doesnt support ForEach (%T)", tree)
+	tree, err := sm.StateTree(root)
+	if err != nil {
+		return cid.Undef, xerrors.Errorf("getting state tree: %w", err)
 	}

 	type transfer struct {
@@ -121,7 +282,7 @@ func UpgradeFaucetBurnRecovery(ctx context.Context, sm *StateManager, tree types
 	var transfers []transfer

 	// Take all excess funds away, put them into the reserve account
-	err = fetree.ForEach(func(addr address.Address, act *types.Actor) error {
+	err = tree.ForEach(func(addr address.Address, act *types.Actor) error {
 		switch act.Code {
 		case builtin0.AccountActorCodeID, builtin0.MultisigActorCodeID, builtin0.PaymentChannelActorCodeID:
 			sysAcc, err := isSystemAccount(addr)
@@ -163,13 +324,13 @@ func UpgradeFaucetBurnRecovery(ctx context.Context, sm *StateManager, tree types
 		return nil
 	})
 	if err != nil {
-		return xerrors.Errorf("foreach over state tree failed: %w", err)
+		return cid.Undef, xerrors.Errorf("foreach over state tree failed: %w", err)
 	}

 	// Execute transfers from previous step
 	for _, t := range transfers {
-		if err := doTransfer(tree, t.From, t.To, t.Amt); err != nil {
-			return xerrors.Errorf("transfer %s %s->%s failed: %w", t.Amt, t.From, t.To, err)
+		if err := doTransfer(cb, tree, t.From, t.To, t.Amt); err != nil {
+			return cid.Undef, xerrors.Errorf("transfer %s %s->%s failed: %w", t.Amt, t.From, t.To, err)
 		}
 	}

@@ -177,19 +338,19 @@ func UpgradeFaucetBurnRecovery(ctx context.Context, sm *StateManager, tree types
 	var ps power0.State
 	powAct, err := tree.GetActor(builtin0.StoragePowerActorAddr)
 	if err != nil {
-		return xerrors.Errorf("failed to load power actor: %w", err)
+		return cid.Undef, xerrors.Errorf("failed to load power actor: %w", err)
 	}

 	cst := cbor.NewCborStore(sm.ChainStore().Blockstore())
 	if err := cst.Get(ctx, powAct.Head, &ps); err != nil {
-		return xerrors.Errorf("failed to get power actor state: %w", err)
+		return cid.Undef, xerrors.Errorf("failed to get power actor state: %w", err)
 	}

 	totalPower := ps.TotalBytesCommitted

 	var transfersBack []transfer
 	// Now, we return some funds to places where they are needed
-	err = fetree.ForEach(func(addr address.Address, act *types.Actor) error {
+	err = tree.ForEach(func(addr address.Address, act *types.Actor) error {
 		lbact, err := lbtree.GetActor(addr)
 		if err != nil {
 			if !xerrors.Is(err, types.ErrActorNotFound) {
@@ -267,53 +428,438 @@ func UpgradeFaucetBurnRecovery(ctx context.Context, sm *StateManager, tree types
 		return nil
 	})
 	if err != nil {
-		return xerrors.Errorf("foreach over state tree failed: %w", err)
+		return cid.Undef, xerrors.Errorf("foreach over state tree failed: %w", err)
 	}

 	for _, t := range transfersBack {
-		if err := doTransfer(tree, t.From, t.To, t.Amt); err != nil {
-			return xerrors.Errorf("transfer %s %s->%s failed: %w", t.Amt, t.From, t.To, err)
+		if err := doTransfer(cb, tree, t.From, t.To, t.Amt); err != nil {
+			return cid.Undef, xerrors.Errorf("transfer %s %s->%s failed: %w", t.Amt, t.From, t.To, err)
 		}
 	}

 	// transfer all burnt funds back to the reserve account
 	burntAct, err := tree.GetActor(builtin0.BurntFundsActorAddr)
 	if err != nil {
-		return xerrors.Errorf("failed to load burnt funds actor: %w", err)
+		return cid.Undef, xerrors.Errorf("failed to load burnt funds actor: %w", err)
 	}
-	if err := doTransfer(tree, builtin0.BurntFundsActorAddr, ReserveAddress, burntAct.Balance); err != nil {
-		return xerrors.Errorf("failed to unburn funds: %w", err)
+	if err := doTransfer(cb, tree, builtin0.BurntFundsActorAddr, ReserveAddress, burntAct.Balance); err != nil {
+		return cid.Undef, xerrors.Errorf("failed to unburn funds: %w", err)
 	}

 	// Top up the reimbursement service
 	reimbAddr, err := address.NewFromString("t0111")
 	if err != nil {
-		return xerrors.Errorf("failed to parse reimbursement service address")
+		return cid.Undef, xerrors.Errorf("failed to parse reimbursement service address")
 	}

 	reimb, err := tree.GetActor(reimbAddr)
 	if err != nil {
-		return xerrors.Errorf("failed to load reimbursement account actor: %w", err)
+		return cid.Undef, xerrors.Errorf("failed to load reimbursement account actor: %w", err)
 	}

 	difference := types.BigSub(DesiredReimbursementBalance, reimb.Balance)
-	if err := doTransfer(tree, ReserveAddress, reimbAddr, difference); err != nil {
-		return xerrors.Errorf("failed to top up reimbursement account: %w", err)
+	if err := doTransfer(cb, tree, ReserveAddress, reimbAddr, difference); err != nil {
+		return cid.Undef, xerrors.Errorf("failed to top up reimbursement account: %w", err)
 	}

 	// Now, a final sanity check to make sure the balances all check out
 	total := abi.NewTokenAmount(0)
-	err = fetree.ForEach(func(addr address.Address, act *types.Actor) error {
+	err = tree.ForEach(func(addr address.Address, act *types.Actor) error {
 		total = types.BigAdd(total, act.Balance)
 		return nil
 	})
 	if err != nil {
-		return xerrors.Errorf("checking final state balance failed: %w", err)
+		return cid.Undef, xerrors.Errorf("checking final state balance failed: %w", err)
 	}

 	exp := types.FromFil(build.FilBase)
 	if !exp.Equals(total) {
-		return xerrors.Errorf("resultant state tree account balance was not correct: %s", total)
+		return cid.Undef, xerrors.Errorf("resultant state tree account balance was not correct: %s", total)
+	}
+
+	return tree.Flush(ctx)
+}
+
+func UpgradeIgnition(ctx context.Context, sm *StateManager, cb ExecCallback, root cid.Cid, epoch abi.ChainEpoch, ts *types.TipSet) (cid.Cid, error) {
+	store := sm.cs.Store(ctx)
+
+	if build.UpgradeLiftoffHeight <= epoch {
+		return cid.Undef, xerrors.Errorf("liftoff height must be beyond ignition height")
+	}
+
+	nst, err := nv3.MigrateStateTree(ctx, store, root, epoch)
+	if err != nil {
+		return cid.Undef, xerrors.Errorf("migrating actors state: %w", err)
+	}
+
+	tree, err := sm.StateTree(nst)
+	if err != nil {
+		return cid.Undef, xerrors.Errorf("getting state tree: %w", err)
+	}
+
+	err = setNetworkName(ctx, store, tree, "ignition")
+	if err != nil {
+		return cid.Undef, xerrors.Errorf("setting network name: %w", err)
+	}
+
+	split1, err := address.NewFromString("t0115")
+	if err != nil {
+		return cid.Undef, xerrors.Errorf("first split address: %w", err)
+	}
+
+	split2, err := address.NewFromString("t0116")
+	if err != nil {
+		return cid.Undef, xerrors.Errorf("second split address: %w", err)
+	}
+
+	err = resetGenesisMsigs(ctx, sm, store, tree, build.UpgradeLiftoffHeight)
+	if err != nil {
+		return cid.Undef, xerrors.Errorf("resetting genesis msig start epochs: %w", err)
+	}
+
+	err = splitGenesisMultisig(ctx, cb, split1, store, tree, 50)
+	if err != nil {
+		return cid.Undef, xerrors.Errorf("splitting first msig: %w", err)
+	}
+
+	err = splitGenesisMultisig(ctx, cb, split2, store, tree, 50)
+	if err != nil {
+		return cid.Undef, xerrors.Errorf("splitting second msig: %w", err)
+	}
+
+	err = nv3.CheckStateTree(ctx, store, nst, epoch, builtin0.TotalFilecoin)
+	if err != nil {
+		return cid.Undef, xerrors.Errorf("sanity check after ignition upgrade failed: %w", err)
+	}
+
+	return tree.Flush(ctx)
+}
+
+func UpgradeRefuel(ctx context.Context, sm *StateManager, cb ExecCallback, root cid.Cid, epoch abi.ChainEpoch, ts *types.TipSet) (cid.Cid, error) {
+
+	store := sm.cs.Store(ctx)
+	tree, err := sm.StateTree(root)
+	if err != nil {
+		return cid.Undef, xerrors.Errorf("getting state tree: %w", err)
+	}
+
+	addr, err := address.NewFromString("t0122")
+	if err != nil {
+		return cid.Undef, xerrors.Errorf("getting address: %w", err)
+	}
+
+	err = resetMultisigVesting(ctx, store, tree, addr, 0, 0, big.Zero())
+	if err != nil {
+		return cid.Undef, xerrors.Errorf("tweaking msig vesting: %w", err)
+	}
+
+	err = resetMultisigVesting(ctx, store, tree, builtin.ReserveAddress, 0, 0, big.Zero())
+	if err != nil {
+		return cid.Undef, xerrors.Errorf("tweaking msig vesting: %w", err)
+	}
+
+	err = resetMultisigVesting(ctx, store, tree, builtin.RootVerifierAddress, 0, 0, big.Zero())
+	if err != nil {
+		return cid.Undef, xerrors.Errorf("tweaking msig vesting: %w", err)
+	}
+
+	return tree.Flush(ctx)
+}
+
+func UpgradeActorsV2(ctx context.Context, sm *StateManager, cb ExecCallback, root cid.Cid, epoch abi.ChainEpoch, ts *types.TipSet) (cid.Cid, error) {
+	buf := bufbstore.NewTieredBstore(sm.cs.Blockstore(), bstore.NewTemporarySync())
+	store := store.ActorStore(ctx, buf)
+
+	info, err := store.Put(ctx, new(types.StateInfo0))
+	if err != nil {
+		return cid.Undef, xerrors.Errorf("failed to create new state info for actors v2: %w", err)
+	}
+
+	newHamtRoot, err := m2.MigrateStateTree(ctx, store, root, epoch, m2.DefaultConfig())
+	if err != nil {
+		return cid.Undef, xerrors.Errorf("upgrading to actors v2: %w", err)
+	}
+
+	newStateTree, err := states2.LoadTree(store, newHamtRoot)
+	if err != nil {
+		return cid.Undef, xerrors.Errorf("failed to load new state tree: %w", err)
+	}
+
+	// Check all state-tree invariants.
+	if msgs, err := states2.CheckStateInvariants(newStateTree, types.TotalFilecoinInt); err != nil {
+		return cid.Undef, xerrors.Errorf("failed to check new state tree: %w", err)
+	} else if !msgs.IsEmpty() {
+		// This error is going to be really nasty.
+		return cid.Undef, xerrors.Errorf("network upgrade failed: %v", msgs.Messages())
+	}
+
+	newRoot, err := store.Put(ctx, &types.StateRoot{
+		Version: types.StateTreeVersion1,
+		Actors:  newHamtRoot,
+		Info:    info,
+	})
+	if err != nil {
+		return cid.Undef, xerrors.Errorf("failed to persist new state root: %w", err)
+	}
+
+	// perform some basic sanity checks to make sure everything still works.
+	if newSm, err := state.LoadStateTree(store, newRoot); err != nil {
+		return cid.Undef, xerrors.Errorf("state tree sanity load failed: %w", err)
+	} else if newRoot2, err := newSm.Flush(ctx); err != nil {
+		return cid.Undef, xerrors.Errorf("state tree sanity flush failed: %w", err)
+	} else if newRoot2 != newRoot {
+		return cid.Undef, xerrors.Errorf("state-root mismatch: %s != %s", newRoot, newRoot2)
+	} else if _, err := newSm.GetActor(builtin0.InitActorAddr); err != nil {
+		return cid.Undef, xerrors.Errorf("failed to load init actor after upgrade: %w", err)
+	}
+
+	{
+		from := buf
+		to := buf.Read()
+
+		if err := vm.Copy(ctx, from, to, newRoot); err != nil {
+			return cid.Undef, xerrors.Errorf("copying migrated tree: %w", err)
+		}
+	}
+
+	return newRoot, nil
+}
+
+func UpgradeLiftoff(ctx context.Context, sm *StateManager, cb ExecCallback, root cid.Cid, epoch abi.ChainEpoch, ts *types.TipSet) (cid.Cid, error) {
+	tree, err := sm.StateTree(root)
+	if err != nil {
+		return cid.Undef, xerrors.Errorf("getting state tree: %w", err)
+	}
+
+	err = setNetworkName(ctx, sm.cs.Store(ctx), tree, "mainnet")
+	if err != nil {
+		return cid.Undef, xerrors.Errorf("setting network name: %w", err)
+	}
+
+	return tree.Flush(ctx)
+}
+
+func setNetworkName(ctx context.Context, store adt.Store, tree *state.StateTree, name string) error {
+	ia, err := tree.GetActor(builtin0.InitActorAddr)
+	if err != nil {
+		return xerrors.Errorf("getting init actor: %w", err)
+	}
+
+	initState, err := init_.Load(store, ia)
+	if err != nil {
+		return xerrors.Errorf("reading init state: %w", err)
+	}
+
+	if err := initState.SetNetworkName(name); err != nil {
+		return xerrors.Errorf("setting network name: %w", err)
+	}
+
+	ia.Head, err = store.Put(ctx, initState)
+	if err != nil {
+		return xerrors.Errorf("writing new init state: %w", err)
+	}
+
+	if err := tree.SetActor(builtin0.InitActorAddr, ia); err != nil {
+		return xerrors.Errorf("setting init actor: %w", err)
+	}
+
+	return nil
+}
+
+func splitGenesisMultisig(ctx context.Context, cb ExecCallback, addr address.Address, store adt0.Store, tree *state.StateTree, portions uint64) error {
+	if portions < 1 {
+		return xerrors.Errorf("cannot split into 0 portions")
+	}
+
+	mact, err := tree.GetActor(addr)
+	if err != nil {
+		return xerrors.Errorf("getting msig actor: %w", err)
+	}
+
+	mst, err := multisig.Load(store, mact)
+	if err != nil {
+		return xerrors.Errorf("getting msig state: %w", err)
+	}
+
+	signers, err := mst.Signers()
+	if err != nil {
+		return xerrors.Errorf("getting msig signers: %w", err)
+	}
+
+	thresh, err := mst.Threshold()
+	if err != nil {
+		return xerrors.Errorf("getting msig threshold: %w", err)
+	}
+
+	ibal, err := mst.InitialBalance()
+	if err != nil {
+		return xerrors.Errorf("getting msig initial balance: %w", err)
+	}
+
+	se, err := mst.StartEpoch()
+	if err != nil {
+		return xerrors.Errorf("getting msig start epoch: %w", err)
+	}
+
+	ud, err := mst.UnlockDuration()
+	if err != nil {
+		return xerrors.Errorf("getting msig unlock duration: %w", err)
+	}
+
+	pending, err := adt0.MakeEmptyMap(store).Root()
+	if err != nil {
+		return xerrors.Errorf("failed to create empty map: %w", err)
+	}
+
+	newIbal := big.Div(ibal, types.NewInt(portions))
+	newState := &multisig0.State{
+		Signers:               signers,
+		NumApprovalsThreshold: thresh,
+		NextTxnID:             0,
+		InitialBalance:        newIbal,
+		StartEpoch:            se,
+		UnlockDuration:        ud,
+		PendingTxns:           pending,
+	}
+
+	scid, err := store.Put(ctx, newState)
+	if err != nil {
+		return xerrors.Errorf("storing new state: %w", err)
+	}
+
+	newActor := types.Actor{
+		Code:    builtin0.MultisigActorCodeID,
+		Head:    scid,
+		Nonce:   0,
+		Balance: big.Zero(),
+	}
+
+	i := uint64(0)
+	for i < portions {
+		keyAddr, err := makeKeyAddr(addr, i)
+		if err != nil {
+			return xerrors.Errorf("creating key address: %w", err)
+		}
+
+		idAddr, err := tree.RegisterNewAddress(keyAddr)
+		if err != nil {
+			return xerrors.Errorf("registering new address: %w", err)
+		}
+
+		err = tree.SetActor(idAddr, &newActor)
+		if err != nil {
+			return xerrors.Errorf("setting new msig actor state: %w", err)
+		}
+
+		if err := doTransfer(cb, tree, addr, idAddr, newIbal); err != nil {
+			return xerrors.Errorf("transferring split msig balance: %w", err)
+		}
+
+		i++
+	}
+
+	return nil
+}
+
+func makeKeyAddr(splitAddr address.Address, count uint64) (address.Address, error) {
+	var b bytes.Buffer
+	if err := splitAddr.MarshalCBOR(&b); err != nil {
+		return address.Undef, xerrors.Errorf("marshalling split address: %w", err)
+	}
+
+	if err := binary.Write(&b, binary.BigEndian, count); err != nil {
+		return address.Undef, xerrors.Errorf("writing count into a buffer: %w", err)
+	}
+
+	if err := binary.Write(&b, binary.BigEndian, []byte("Ignition upgrade")); err != nil {
+		return address.Undef, xerrors.Errorf("writing fork name into a buffer: %w", err)
+	}
+
+	addr, err := address.NewActorAddress(b.Bytes())
+	if err != nil {
+		return address.Undef, xerrors.Errorf("create actor address: %w", err)
+	}
+
+	return addr, nil
+}
+
+// TODO: After the Liftoff epoch, refactor this to use resetMultisigVesting
+func resetGenesisMsigs(ctx context.Context, sm *StateManager, store adt0.Store, tree *state.StateTree, startEpoch abi.ChainEpoch) error {
+	gb, err := sm.cs.GetGenesis()
+	if err != nil {
+		return xerrors.Errorf("getting genesis block: %w", err)
+	}
+
+	gts, err := types.NewTipSet([]*types.BlockHeader{gb})
+	if err != nil {
+		return xerrors.Errorf("getting genesis tipset: %w", err)
+	}
+
+	cst := cbor.NewCborStore(sm.cs.Blockstore())
+	genesisTree, err := state.LoadStateTree(cst, gts.ParentState())
+	if err != nil {
+		return xerrors.Errorf("loading state tree: %w", err)
+	}
+
+	err = genesisTree.ForEach(func(addr address.Address, genesisActor *types.Actor) error {
+		if genesisActor.Code == builtin0.MultisigActorCodeID {
+			currActor, err := tree.GetActor(addr)
+			if err != nil {
+				return xerrors.Errorf("loading actor: %w", err)
+			}
+
+			var currState multisig0.State
+			if err := store.Get(ctx, currActor.Head, &currState); err != nil {
+				return xerrors.Errorf("reading multisig state: %w", err)
+			}
+
+			currState.StartEpoch = startEpoch
+
+			currActor.Head, err = store.Put(ctx, &currState)
+			if err != nil {
+				return xerrors.Errorf("writing new multisig state: %w", err)
+			}
+
+			if err := tree.SetActor(addr, currActor); err != nil {
+				return xerrors.Errorf("setting multisig actor: %w", err)
+			}
+		}
+		return nil
+	})
+
+	if err != nil {
+		return xerrors.Errorf("iterating over genesis actors: %w", err)
+	}
+
+	return nil
+}
+
+func resetMultisigVesting(ctx context.Context, store adt0.Store, tree *state.StateTree, addr address.Address, startEpoch abi.ChainEpoch, duration abi.ChainEpoch, balance abi.TokenAmount) error {
+	act, err := tree.GetActor(addr)
+	if err != nil {
+		return xerrors.Errorf("getting actor: %w", err)
+	}
+
+	if !builtin.IsMultisigActor(act.Code) {
+		return xerrors.Errorf("actor wasn't msig: %w", err)
+	}
+
+	var msigState multisig0.State
+	if err := store.Get(ctx, act.Head, &msigState); err != nil {
+		return xerrors.Errorf("reading multisig state: %w", err)
+	}
+
+	msigState.StartEpoch = startEpoch
+	msigState.UnlockDuration = duration
+	msigState.InitialBalance = balance
+
+	act.Head, err = store.Put(ctx, &msigState)
+	if err != nil {
+		return xerrors.Errorf("writing new multisig state: %w", err)
+	}
+
+	if err := tree.SetActor(addr, act); err != nil {
+		return xerrors.Errorf("setting multisig actor: %w", err)
 	}

 	return nil
@@ -8,37 +8,34 @@ import (

 	"github.com/filecoin-project/go-address"
 	"github.com/filecoin-project/go-state-types/abi"
-	"github.com/filecoin-project/go-state-types/big"
+	"github.com/filecoin-project/go-state-types/cbor"
 	"github.com/filecoin-project/specs-actors/actors/builtin"
-	init_ "github.com/filecoin-project/specs-actors/actors/builtin/init"
-	miner0 "github.com/filecoin-project/specs-actors/actors/builtin/miner"
-	power0 "github.com/filecoin-project/specs-actors/actors/builtin/power"
-	verifreg0 "github.com/filecoin-project/specs-actors/actors/builtin/verifreg"
+	init0 "github.com/filecoin-project/specs-actors/actors/builtin/init"
 	"github.com/filecoin-project/specs-actors/actors/runtime"
+	"github.com/stretchr/testify/require"
 	"golang.org/x/xerrors"

 	"github.com/filecoin-project/lotus/chain/actors"
 	"github.com/filecoin-project/lotus/chain/actors/aerrors"
 	lotusinit "github.com/filecoin-project/lotus/chain/actors/builtin/init"
+	"github.com/filecoin-project/lotus/chain/actors/policy"
 	"github.com/filecoin-project/lotus/chain/gen"
-	"github.com/filecoin-project/lotus/chain/stmgr"
 	. "github.com/filecoin-project/lotus/chain/stmgr"
 	"github.com/filecoin-project/lotus/chain/types"
 	"github.com/filecoin-project/lotus/chain/vm"
 	_ "github.com/filecoin-project/lotus/lib/sigs/bls"
 	_ "github.com/filecoin-project/lotus/lib/sigs/secp"

-	cbor "github.com/ipfs/go-ipld-cbor"
+	"github.com/ipfs/go-cid"
+	ipldcbor "github.com/ipfs/go-ipld-cbor"
 	logging "github.com/ipfs/go-log"
 	cbg "github.com/whyrusleeping/cbor-gen"
 )

 func init() {
-	miner0.SupportedProofTypes = map[abi.RegisteredSealProof]struct{}{
-		abi.RegisteredSealProof_StackedDrg2KiBV1: {},
-	}
-	power0.ConsensusMinerMinPower = big.NewInt(2048)
-	verifreg0.MinVerifiedDealSize = big.NewInt(256)
+	policy.SetSupportedProofTypes(abi.RegisteredSealProof_StackedDrg2KiBV1)
+	policy.SetConsensusMinerMinPower(abi.NewStoragePower(2048))
+	policy.SetMinVerifiedDealSize(abi.NewStoragePower(256))
 }

 const testForkHeight = 40
@@ -46,6 +43,10 @@ const testForkHeight = 40
 type testActor struct {
 }

+// must use existing actor that an account is allowed to exec.
+func (testActor) Code() cid.Cid  { return builtin.PaymentChannelActorCodeID }
+func (testActor) State() cbor.Er { return new(testActorState) }
+
 type testActorState struct {
 	HasUpgraded uint64
 }
@@ -66,7 +67,7 @@ func (tas *testActorState) UnmarshalCBOR(r io.Reader) error {
 	return nil
 }

-func (ta *testActor) Exports() []interface{} {
+func (ta testActor) Exports() []interface{} {
 	return []interface{}{
 		1: ta.Constructor,
 		2: ta.TestMethod,
@@ -76,7 +77,7 @@ func (ta *testActor) Exports() []interface{} {
 func (ta *testActor) Constructor(rt runtime.Runtime, params *abi.EmptyValue) *abi.EmptyValue {
 	rt.ValidateImmediateCallerAcceptAny()
 	rt.StateCreate(&testActorState{11})
-	fmt.Println("NEW ACTOR ADDRESS IS: ", rt.Receiver())
+	//fmt.Println("NEW ACTOR ADDRESS IS: ", rt.Receiver())

 	return abi.Empty
 }
@@ -109,46 +110,57 @@ func TestForkHeightTriggers(t *testing.T) {
 		t.Fatal(err)
 	}

-	sm := NewStateManager(cg.ChainStore())
-
-	inv := vm.NewInvoker()
-
 	// predicting the address here... may break if other assumptions change
 	taddr, err := address.NewIDAddress(1002)
 	if err != nil {
 		t.Fatal(err)
 	}

-	stmgr.ForksAtHeight[testForkHeight] = func(ctx context.Context, sm *StateManager, st types.StateTree, ts *types.TipSet) error {
-		cst := cbor.NewCborStore(sm.ChainStore().Blockstore())
+	sm, err := NewStateManagerWithUpgradeSchedule(
+		cg.ChainStore(), UpgradeSchedule{{
+			Network: 1,
+			Height:  testForkHeight,
+			Migration: func(ctx context.Context, sm *StateManager, cb ExecCallback,
+				root cid.Cid, height abi.ChainEpoch, ts *types.TipSet) (cid.Cid, error) {
+				cst := ipldcbor.NewCborStore(sm.ChainStore().Blockstore())

-		act, err := st.GetActor(taddr)
-		if err != nil {
-			return err
-		}
+				st, err := sm.StateTree(root)
+				if err != nil {
+					return cid.Undef, xerrors.Errorf("getting state tree: %w", err)
+				}

-		var tas testActorState
-		if err := cst.Get(ctx, act.Head, &tas); err != nil {
-			return xerrors.Errorf("in fork handler, failed to run get: %w", err)
-		}
+				act, err := st.GetActor(taddr)
+				if err != nil {
+					return cid.Undef, err
+				}

-		tas.HasUpgraded = 55
+				var tas testActorState
+				if err := cst.Get(ctx, act.Head, &tas); err != nil {
+					return cid.Undef, xerrors.Errorf("in fork handler, failed to run get: %w", err)
+				}

-		ns, err := cst.Put(ctx, &tas)
-		if err != nil {
-			return err
-		}
+				tas.HasUpgraded = 55

-		act.Head = ns
+				ns, err := cst.Put(ctx, &tas)
+				if err != nil {
+					return cid.Undef, err
+				}

-		if err := st.SetActor(taddr, act); err != nil {
-			return err
-		}
+				act.Head = ns

-		return nil
+				if err := st.SetActor(taddr, act); err != nil {
+					return cid.Undef, err
+				}
+
+				return st.Flush(ctx)
+			}}})
+	if err != nil {
+		t.Fatal(err)
 	}

-	inv.Register(builtin.PaymentChannelActorCodeID, &testActor{}, &testActorState{})
+	inv := vm.NewActorRegistry()
+	inv.Register(nil, testActor{})
+
 	sm.SetVMConstructor(func(ctx context.Context, vmopt *vm.VMOpts) (*vm.VM, error) {
 		nvm, err := vm.NewVM(ctx, vmopt)
 		if err != nil {
@@ -162,7 +174,7 @@ func TestForkHeightTriggers(t *testing.T) {

 	var msgs []*types.SignedMessage

-	enc, err := actors.SerializeParams(&init_.ExecParams{CodeCID: builtin.PaymentChannelActorCodeID})
+	enc, err := actors.SerializeParams(&init0.ExecParams{CodeCID: (testActor{}).Code()})
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -222,3 +234,84 @@ func TestForkHeightTriggers(t *testing.T) {
 		}
 	}
 }
+
+func TestForkRefuseCall(t *testing.T) {
+	logging.SetAllLoggers(logging.LevelInfo)
+
+	ctx := context.TODO()
+
+	cg, err := gen.NewGenerator()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	sm, err := NewStateManagerWithUpgradeSchedule(
+		cg.ChainStore(), UpgradeSchedule{{
+			Network:   1,
+			Expensive: true,
+			Height:    testForkHeight,
+			Migration: func(ctx context.Context, sm *StateManager, cb ExecCallback,
+				root cid.Cid, height abi.ChainEpoch, ts *types.TipSet) (cid.Cid, error) {
+				return root, nil
+			}}})
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	inv := vm.NewActorRegistry()
+	inv.Register(nil, testActor{})
+
+	sm.SetVMConstructor(func(ctx context.Context, vmopt *vm.VMOpts) (*vm.VM, error) {
+		nvm, err := vm.NewVM(ctx, vmopt)
+		if err != nil {
+			return nil, err
+		}
+		nvm.SetInvoker(inv)
+		return nvm, nil
+	})
+
+	cg.SetStateManager(sm)
+
+	enc, err := actors.SerializeParams(&init0.ExecParams{CodeCID: (testActor{}).Code()})
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	m := &types.Message{
+		From:       cg.Banker(),
+		To:         lotusinit.Address,
+		Method:     builtin.MethodsInit.Exec,
+		Params:     enc,
+		GasLimit:   types.TestGasLimit,
+		Value:      types.NewInt(0),
+		GasPremium: types.NewInt(0),
+		GasFeeCap:  types.NewInt(0),
+	}
+
+	for i := 0; i < 50; i++ {
+		ts, err := cg.NextTipSet()
+		if err != nil {
+			t.Fatal(err)
+		}
+
+		ret, err := sm.CallWithGas(ctx, m, nil, ts.TipSet.TipSet())
+		switch ts.TipSet.TipSet().Height() {
+		case testForkHeight, testForkHeight + 1:
+			// If I had a fork, or I _will_ have a fork, it should fail.
+			require.Equal(t, ErrExpensiveFork, err)
+		default:
+			require.NoError(t, err)
+			require.True(t, ret.MsgRct.ExitCode.IsSuccess())
+		}
+		// Call just runs on the parent state for a tipset, so we only
+		// expect an error at the fork height.
+		ret, err = sm.Call(ctx, m, ts.TipSet.TipSet())
+		switch ts.TipSet.TipSet().Height() {
+		case testForkHeight + 1:
+			require.Equal(t, ErrExpensiveFork, err)
+		default:
+			require.NoError(t, err)
+			require.True(t, ret.MsgRct.ExitCode.IsSuccess())
+		}
+	}
+}
@@ -5,6 +5,8 @@ import (
 	"fmt"
 	"sync"

+	"github.com/filecoin-project/lotus/chain/actors/builtin"
+
 	builtin0 "github.com/filecoin-project/specs-actors/actors/builtin"
 	msig0 "github.com/filecoin-project/specs-actors/actors/builtin/multisig"

@@ -24,7 +26,6 @@ import (
 	"github.com/filecoin-project/lotus/build"
 	"github.com/filecoin-project/lotus/chain/actors"
 	"github.com/filecoin-project/lotus/chain/actors/adt"
-	"github.com/filecoin-project/lotus/chain/actors/builtin"
 	"github.com/filecoin-project/lotus/chain/actors/builtin/market"
 	"github.com/filecoin-project/lotus/chain/actors/builtin/multisig"
 	"github.com/filecoin-project/lotus/chain/actors/builtin/paych"
@@ -38,24 +39,83 @@ import (

 var log = logging.Logger("statemgr")

+type versionSpec struct {
+	networkVersion network.Version
+	atOrBelow      abi.ChainEpoch
+}
+
 type StateManager struct {
 	cs *store.ChainStore

-	stCache       map[string][]cid.Cid
-	compWait      map[string]chan struct{}
-	stlk          sync.Mutex
-	genesisMsigLk sync.Mutex
-	newVM         func(context.Context, *vm.VMOpts) (*vm.VM, error)
-	genInfo       *genesisInfo
+	// Determines the network version at any given epoch.
+	networkVersions []versionSpec
+	latestVersion   network.Version
+
+	// Maps chain epochs to upgrade functions.
+	stateMigrations map[abi.ChainEpoch]UpgradeFunc
+	// A set of potentially expensive/time consuming upgrades. Explicit
+	// calls for, e.g., gas estimation fail against this epoch with
+	// ErrExpensiveFork.
+	expensiveUpgrades map[abi.ChainEpoch]struct{}
+
+	stCache              map[string][]cid.Cid
+	compWait             map[string]chan struct{}
+	stlk                 sync.Mutex
+	genesisMsigLk        sync.Mutex
+	newVM                func(context.Context, *vm.VMOpts) (*vm.VM, error)
+	preIgnitionGenInfos  *genesisInfo
+	postIgnitionGenInfos *genesisInfo
 }

 func NewStateManager(cs *store.ChainStore) *StateManager {
-	return &StateManager{
-		newVM:    vm.NewVM,
-		cs:       cs,
-		stCache:  make(map[string][]cid.Cid),
-		compWait: make(map[string]chan struct{}),
+	sm, err := NewStateManagerWithUpgradeSchedule(cs, DefaultUpgradeSchedule())
+	if err != nil {
+		panic(fmt.Sprintf("default upgrade schedule is invalid: %s", err))
 	}
+	return sm
+}
+
+func NewStateManagerWithUpgradeSchedule(cs *store.ChainStore, us UpgradeSchedule) (*StateManager, error) {
+	// If we have upgrades, make sure they're in-order and make sense.
+	if err := us.Validate(); err != nil {
+		return nil, err
+	}
+
+	stateMigrations := make(map[abi.ChainEpoch]UpgradeFunc, len(us))
+	expensiveUpgrades := make(map[abi.ChainEpoch]struct{}, len(us))
+	var networkVersions []versionSpec
+	lastVersion := network.Version0
+	if len(us) > 0 {
+		// If we have any upgrades, process them and create a version
+		// schedule.
+		for _, upgrade := range us {
+			if upgrade.Migration != nil {
+				stateMigrations[upgrade.Height] = upgrade.Migration
+			}
+			if upgrade.Expensive {
+				expensiveUpgrades[upgrade.Height] = struct{}{}
+			}
+			networkVersions = append(networkVersions, versionSpec{
+				networkVersion: lastVersion,
+				atOrBelow:      upgrade.Height,
+			})
+			lastVersion = upgrade.Network
+		}
+	} else {
+		// Otherwise, go directly to the latest version.
+		lastVersion = build.NewestNetworkVersion
+	}
+
+	return &StateManager{
+		networkVersions:   networkVersions,
+		latestVersion:     lastVersion,
+		stateMigrations:   stateMigrations,
+		expensiveUpgrades: expensiveUpgrades,
+		newVM:             vm.NewVM,
+		cs:                cs,
+		stCache:           make(map[string][]cid.Cid),
+		compWait:          make(map[string]chan struct{}),
+	}, nil
 }

 func cidsToKey(cids []cid.Cid) string {
@@ -123,9 +183,8 @@ func (sm *StateManager) TipSetState(ctx context.Context, ts *types.TipSet) (st c
 	return st, rec, nil
 }

-func (sm *StateManager) ExecutionTrace(ctx context.Context, ts *types.TipSet) (cid.Cid, []*api.InvocResult, error) {
-	var trace []*api.InvocResult
-	st, _, err := sm.computeTipSetState(ctx, ts, func(mcid cid.Cid, msg *types.Message, ret *vm.ApplyRet) error {
+func traceFunc(trace *[]*api.InvocResult) func(mcid cid.Cid, msg *types.Message, ret *vm.ApplyRet) error {
+	return func(mcid cid.Cid, msg *types.Message, ret *vm.ApplyRet) error {
 		ir := &api.InvocResult{
 			Msg:            msg,
 			MsgRct:         &ret.MessageReceipt,
@@ -135,9 +194,14 @@ func (sm *StateManager) ExecutionTrace(ctx context.Context, ts *types.TipSet) (c
 		if ret.ActorErr != nil {
 			ir.Error = ret.ActorErr.Error()
 		}
-		trace = append(trace, ir)
+		*trace = append(*trace, ir)
 		return nil
-	})
+	}
+}
+
+func (sm *StateManager) ExecutionTrace(ctx context.Context, ts *types.TipSet) (cid.Cid, []*api.InvocResult, error) {
+	var trace []*api.InvocResult
+	st, _, err := sm.computeTipSetState(ctx, ts, traceFunc(&trace))
 	if err != nil {
 		return cid.Undef, nil, err
 	}
@@ -149,20 +213,24 @@ type ExecCallback func(cid.Cid, *types.Message, *vm.ApplyRet) error

 func (sm *StateManager) ApplyBlocks(ctx context.Context, parentEpoch abi.ChainEpoch, pstate cid.Cid, bms []store.BlockMessages, epoch abi.ChainEpoch, r vm.Rand, cb ExecCallback, baseFee abi.TokenAmount, ts *types.TipSet) (cid.Cid, cid.Cid, error) {

-	vmopt := &vm.VMOpts{
-		StateBase:      pstate,
-		Epoch:          epoch,
-		Rand:           r,
-		Bstore:         sm.cs.Blockstore(),
-		Syscalls:       sm.cs.VMSys(),
-		CircSupplyCalc: sm.GetCirculatingSupply,
-		NtwkVersion:    sm.GetNtwkVersion,
-		BaseFee:        baseFee,
+	makeVmWithBaseState := func(base cid.Cid) (*vm.VM, error) {
+		vmopt := &vm.VMOpts{
+			StateBase:      base,
+			Epoch:          epoch,
+			Rand:           r,
+			Bstore:         sm.cs.Blockstore(),
+			Syscalls:       sm.cs.VMSys(),
+			CircSupplyCalc: sm.GetCirculatingSupply,
+			NtwkVersion:    sm.GetNtwkVersion,
+			BaseFee:        baseFee,
+		}
+
+		return sm.newVM(ctx, vmopt)
 	}

-	vmi, err := sm.newVM(ctx, vmopt)
+	vmi, err := makeVmWithBaseState(pstate)
 	if err != nil {
-		return cid.Undef, cid.Undef, xerrors.Errorf("instantiating VM failed: %w", err)
+		return cid.Undef, cid.Undef, xerrors.Errorf("making vm: %w", err)
 	}

 	runCron := func() error {
@@ -200,21 +268,34 @@ func (sm *StateManager) ApplyBlocks(ctx context.Context, parentEpoch abi.ChainEp
 	}

 	for i := parentEpoch; i < epoch; i++ {
+		if i > parentEpoch {
+			// run cron for null rounds if any
+			if err := runCron(); err != nil {
+				return cid.Undef, cid.Undef, err
+			}
+
+			pstate, err = vmi.Flush(ctx)
+			if err != nil {
+				return cid.Undef, cid.Undef, xerrors.Errorf("flushing vm: %w", err)
+			}
+		}
+
 		// handle state forks
 		// XXX: The state tree
-		err = sm.handleStateForks(ctx, vmi.StateTree(), i, ts)
+		newState, err := sm.handleStateForks(ctx, pstate, i, cb, ts)
 		if err != nil {
 			return cid.Undef, cid.Undef, xerrors.Errorf("error handling state forks: %w", err)
 		}

-		if i > parentEpoch {
-			// run cron for null rounds if any
-			if err := runCron(); err != nil {
-				return cid.Cid{}, cid.Cid{}, err
+		if pstate != newState {
+			vmi, err = makeVmWithBaseState(newState)
+			if err != nil {
+				return cid.Undef, cid.Undef, xerrors.Errorf("making vm: %w", err)
 			}
 		}

 		vmi.SetBlockHeight(i + 1)
+		pstate = newState
 	}

 	var receipts []cbg.CBORMarshaler
@@ -257,7 +338,7 @@ func (sm *StateManager) ApplyBlocks(ctx context.Context, parentEpoch abi.ChainEp

 		sysAct, actErr := vmi.StateTree().GetActor(builtin0.SystemActorAddr)
 		if actErr != nil {
-			return cid.Undef, cid.Undef, xerrors.Errorf("failed to get system actor: %w", err)
+			return cid.Undef, cid.Undef, xerrors.Errorf("failed to get system actor: %w", actErr)
 		}

 		rwMsg := &types.Message{
@@ -273,7 +354,7 @@ func (sm *StateManager) ApplyBlocks(ctx context.Context, parentEpoch abi.ChainEp
 		}
 		ret, actErr := vmi.ApplyImplicitMessage(ctx, rwMsg)
 		if actErr != nil {
-			return cid.Undef, cid.Undef, xerrors.Errorf("failed to apply reward message for miner %s: %w", b.Miner, err)
+			return cid.Undef, cid.Undef, xerrors.Errorf("failed to apply reward message for miner %s: %w", b.Miner, actErr)
 		}
 		if cb != nil {
 			if err := cb(rwMsg.Cid(), rwMsg, ret); err != nil {
@@ -291,7 +372,7 @@ func (sm *StateManager) ApplyBlocks(ctx context.Context, parentEpoch abi.ChainEp
 	}

 	// XXX: Is the height correct? Or should it be epoch-1?
-	rectarr, err := adt.NewArray(sm.cs.Store(ctx), builtin.VersionForNetwork(sm.GetNtwkVersion(ctx, epoch)))
+	rectarr, err := adt.NewArray(sm.cs.Store(ctx), actors.VersionForNetwork(sm.GetNtwkVersion(ctx, epoch)))
 	if err != nil {
 		return cid.Undef, cid.Undef, xerrors.Errorf("failed to create receipts amt: %w", err)
 	}
@@ -837,7 +918,7 @@ func (sm *StateManager) setupGenesisActors(ctx context.Context) error {

 	totalsByEpoch := make(map[abi.ChainEpoch]abi.TokenAmount)
 	err = sTree.ForEach(func(kaddr address.Address, act *types.Actor) error {
-		if act.IsMultisigActor() {
+		if builtin.IsMultisigActor(act.Code) {
 			s, err := multisig.Load(sm.cs.Store(ctx), act)
 			if err != nil {
 				return err
@@ -869,7 +950,7 @@ func (sm *StateManager) setupGenesisActors(ctx context.Context) error {
 				totalsByEpoch[ud] = ib
 			}

-		} else if act.IsAccountActor() {
+		} else if builtin.IsAccountActor(act.Code) {
 			// should exclude burnt funds actor and "remainder account actor"
 			// should only ever be "faucet" accounts in testnets
 			if kaddr == builtin0.BurntFundsActorAddr {
@@ -904,7 +985,7 @@ func (sm *StateManager) setupGenesisActors(ctx context.Context) error {
 		gi.genesisMsigs = append(gi.genesisMsigs, ns)
 	}

-	sm.genInfo = &gi
+	sm.preIgnitionGenInfos = &gi

 	return nil
 }
@@ -912,7 +993,7 @@ func (sm *StateManager) setupGenesisActors(ctx context.Context) error {
 // sets up information about the actors in the genesis state
 // For testnet we use a hardcoded set of multisig states, instead of what's actually in the genesis multisigs
 // We also do not consider ANY account actors (including the faucet)
-func (sm *StateManager) setupGenesisActorsTestnet(ctx context.Context) error {
+func (sm *StateManager) setupPreIgnitionGenesisActorsTestnet(ctx context.Context) error {

 	gi := genesisInfo{}

@@ -981,7 +1062,87 @@ func (sm *StateManager) setupGenesisActorsTestnet(ctx context.Context) error {
 		gi.genesisMsigs = append(gi.genesisMsigs, ns)
 	}

-	sm.genInfo = &gi
+	sm.preIgnitionGenInfos = &gi
+
+	return nil
+}
+
+// sets up information about the actors in the genesis state, post the ignition fork
+func (sm *StateManager) setupPostIgnitionGenesisActors(ctx context.Context) error {
+
+	gi := genesisInfo{}
+
+	gb, err := sm.cs.GetGenesis()
+	if err != nil {
+		return xerrors.Errorf("getting genesis block: %w", err)
+	}
+
+	gts, err := types.NewTipSet([]*types.BlockHeader{gb})
+	if err != nil {
+		return xerrors.Errorf("getting genesis tipset: %w", err)
+	}
+
+	st, _, err := sm.TipSetState(ctx, gts)
+	if err != nil {
+		return xerrors.Errorf("getting genesis tipset state: %w", err)
+	}
+
+	cst := cbor.NewCborStore(sm.cs.Blockstore())
+	sTree, err := state.LoadStateTree(cst, st)
+	if err != nil {
+		return xerrors.Errorf("loading state tree: %w", err)
+	}
+
+	// Unnecessary, should be removed
+	gi.genesisMarketFunds, err = getFilMarketLocked(ctx, sTree)
+	if err != nil {
+		return xerrors.Errorf("setting up genesis market funds: %w", err)
+	}
+
+	// Unnecessary, should be removed
+	gi.genesisPledge, err = getFilPowerLocked(ctx, sTree)
+	if err != nil {
+		return xerrors.Errorf("setting up genesis pledge: %w", err)
+	}
+
+	totalsByEpoch := make(map[abi.ChainEpoch]abi.TokenAmount)
+
+	// 6 months
+	sixMonths := abi.ChainEpoch(183 * builtin0.EpochsInDay)
+	totalsByEpoch[sixMonths] = big.NewInt(49_929_341)
+	totalsByEpoch[sixMonths] = big.Add(totalsByEpoch[sixMonths], big.NewInt(32_787_700))
+
+	// 1 year
+	oneYear := abi.ChainEpoch(365 * builtin0.EpochsInDay)
+	totalsByEpoch[oneYear] = big.NewInt(22_421_712)
+
+	// 2 years
+	twoYears := abi.ChainEpoch(2 * 365 * builtin0.EpochsInDay)
+	totalsByEpoch[twoYears] = big.NewInt(7_223_364)
+
+	// 3 years
+	threeYears := abi.ChainEpoch(3 * 365 * builtin0.EpochsInDay)
+	totalsByEpoch[threeYears] = big.NewInt(87_637_883)
+
+	// 6 years
+	sixYears := abi.ChainEpoch(6 * 365 * builtin0.EpochsInDay)
+	totalsByEpoch[sixYears] = big.NewInt(100_000_000)
+	totalsByEpoch[sixYears] = big.Add(totalsByEpoch[sixYears], big.NewInt(300_000_000))
+
+	gi.genesisMsigs = make([]msig0.State, 0, len(totalsByEpoch))
+	for k, v := range totalsByEpoch {
+		ns := msig0.State{
+			// In the pre-ignition logic, we incorrectly set this value in Fil, not attoFil, an off-by-10^18 error
+			InitialBalance: big.Mul(v, big.NewInt(int64(build.FilecoinPrecision))),
+			UnlockDuration: k,
+			PendingTxns:    cid.Undef,
+			// In the pre-ignition logic, the start epoch was 0. This changes in the fork logic of the Ignition upgrade itself.
+			StartEpoch: build.UpgradeLiftoffHeight,
+		}
+		gi.genesisMsigs = append(gi.genesisMsigs, ns)
+	}
+
+	sm.postIgnitionGenInfos = &gi

 	return nil
 }
@@ -991,13 +1152,23 @@ func (sm *StateManager) setupGenesisActorsTestnet(ctx context.Context) error {
 // - For Accounts, it counts max(currentBalance - genesisBalance, 0).
 func (sm *StateManager) GetFilVested(ctx context.Context, height abi.ChainEpoch, st *state.StateTree) (abi.TokenAmount, error) {
 	vf := big.Zero()
-	for _, v := range sm.genInfo.genesisMsigs {
-		au := big.Sub(v.InitialBalance, v.AmountLocked(height))
-		vf = big.Add(vf, au)
+	if height <= build.UpgradeIgnitionHeight {
+		for _, v := range sm.preIgnitionGenInfos.genesisMsigs {
+			au := big.Sub(v.InitialBalance, v.AmountLocked(height))
+			vf = big.Add(vf, au)
+		}
+	} else {
+		for _, v := range sm.postIgnitionGenInfos.genesisMsigs {
+			// In the pre-ignition logic, we simply called AmountLocked(height), assuming startEpoch was 0.
+			// The start epoch changed in the Ignition upgrade.
+			au := big.Sub(v.InitialBalance, v.AmountLocked(height-v.StartEpoch))
+			vf = big.Add(vf, au)
+		}
 	}

 	// there should not be any such accounts in testnet (and also none in mainnet?)
-	for _, v := range sm.genInfo.genesisActors {
+	// continue to use preIgnitionGenInfos, nothing changed at the Ignition epoch
+	for _, v := range sm.preIgnitionGenInfos.genesisActors {
 		act, err := st.GetActor(v.addr)
 		if err != nil {
 			return big.Zero(), xerrors.Errorf("failed to get actor: %w", err)
@@ -1009,12 +1180,27 @@ func (sm *StateManager) GetFilVested(ctx context.Context, height abi.ChainEpoch,
 		}
 	}

-	vf = big.Add(vf, sm.genInfo.genesisPledge)
-	vf = big.Add(vf, sm.genInfo.genesisMarketFunds)
+	// After UpgradeActorsV2Height these funds are accounted for in GetFilReserveDisbursed
+	if height <= build.UpgradeActorsV2Height {
+		// continue to use preIgnitionGenInfos, nothing changed at the Ignition epoch
+		vf = big.Add(vf, sm.preIgnitionGenInfos.genesisPledge)
+		// continue to use preIgnitionGenInfos, nothing changed at the Ignition epoch
+		vf = big.Add(vf, sm.preIgnitionGenInfos.genesisMarketFunds)
+	}

 	return vf, nil
 }

+func GetFilReserveDisbursed(ctx context.Context, st *state.StateTree) (abi.TokenAmount, error) {
+	ract, err := st.GetActor(builtin.ReserveAddress)
+	if err != nil {
+		return big.Zero(), xerrors.Errorf("failed to get reserve actor: %w", err)
+	}
+
+	// If money enters the reserve actor, this could lead to a negative term
+	return big.Sub(big.NewFromGo(build.InitialFilReserved), ract.Balance), nil
+}
+
 func GetFilMined(ctx context.Context, st *state.StateTree) (abi.TokenAmount, error) {
 	ractor, err := st.GetActor(reward.Address)
 	if err != nil {
@@ -1084,10 +1270,16 @@ func GetFilBurnt(ctx context.Context, st *state.StateTree) (abi.TokenAmount, err
 func (sm *StateManager) GetCirculatingSupplyDetailed(ctx context.Context, height abi.ChainEpoch, st *state.StateTree) (api.CirculatingSupply, error) {
 	sm.genesisMsigLk.Lock()
 	defer sm.genesisMsigLk.Unlock()
-	if sm.genInfo == nil {
-		err := sm.setupGenesisActorsTestnet(ctx)
+	if sm.preIgnitionGenInfos == nil {
+		err := sm.setupPreIgnitionGenesisActorsTestnet(ctx)
 		if err != nil {
-			return api.CirculatingSupply{}, xerrors.Errorf("failed to setup genesis information: %w", err)
+			return api.CirculatingSupply{}, xerrors.Errorf("failed to setup pre-ignition genesis information: %w", err)
+		}
+	}
+	if sm.postIgnitionGenInfos == nil {
+		err := sm.setupPostIgnitionGenesisActors(ctx)
+		if err != nil {
+			return api.CirculatingSupply{}, xerrors.Errorf("failed to setup post-ignition genesis information: %w", err)
 		}
 	}

@@ -1096,6 +1288,14 @@ func (sm *StateManager) GetCirculatingSupplyDetailed(ctx context.Context, height
 		return api.CirculatingSupply{}, xerrors.Errorf("failed to calculate filVested: %w", err)
 	}

+	filReserveDisbursed := big.Zero()
+	if height > build.UpgradeActorsV2Height {
+		filReserveDisbursed, err = GetFilReserveDisbursed(ctx, st)
+		if err != nil {
+			return api.CirculatingSupply{}, xerrors.Errorf("failed to calculate filReserveDisbursed: %w", err)
+		}
+	}
+
 	filMined, err := GetFilMined(ctx, st)
 	if err != nil {
 		return api.CirculatingSupply{}, xerrors.Errorf("failed to calculate filMined: %w", err)
@@ -1112,6 +1312,7 @@ func (sm *StateManager) GetCirculatingSupplyDetailed(ctx context.Context, height
 	}

 	ret := types.BigAdd(filVested, filMined)
+	ret = types.BigAdd(ret, filReserveDisbursed)
 	ret = types.BigSub(ret, filBurnt)
 	ret = types.BigSub(ret, filLocked)

@@ -1138,21 +1339,14 @@ func (sm *StateManager) GetCirculatingSupply(ctx context.Context, height abi.Cha
 }

 func (sm *StateManager) GetNtwkVersion(ctx context.Context, height abi.ChainEpoch) network.Version {
-	// TODO: move hard fork epoch checks to a schedule defined in build/
-
-	if build.UseNewestNetwork() {
-		return build.NewestNetworkVersion
+	// The epochs here are the _last_ epoch for every version, or -1 if the
+	// version is disabled.
+	for _, spec := range sm.networkVersions {
+		if height <= spec.atOrBelow {
+			return spec.networkVersion
+		}
 	}
-
-	if height <= build.UpgradeBreezeHeight {
-		return network.Version0
-	}
-
-	if height <= build.UpgradeSmokeHeight {
-		return network.Version1
-	}
-
-	return build.NewestNetworkVersion
+	return sm.latestVersion
 }

 func (sm *StateManager) GetPaychState(ctx context.Context, addr address.Address, ts *types.TipSet) (*types.Actor, paych.State, error) {
@@ -9,6 +9,11 @@ import (
 	"runtime"
 	"strings"

+	"github.com/filecoin-project/go-state-types/big"
+
+	"github.com/filecoin-project/go-state-types/network"
+	"github.com/filecoin-project/lotus/chain/actors/policy"
+
 	cid "github.com/ipfs/go-cid"
 	cbg "github.com/whyrusleeping/cbor-gen"
 	"golang.org/x/xerrors"
@@ -17,22 +22,14 @@ import (
 	"github.com/filecoin-project/go-bitfield"
 	"github.com/filecoin-project/go-state-types/abi"
 	"github.com/filecoin-project/go-state-types/crypto"
+	"github.com/filecoin-project/go-state-types/rt"

 	builtin0 "github.com/filecoin-project/specs-actors/actors/builtin"
-	account0 "github.com/filecoin-project/specs-actors/actors/builtin/account"
-	cron0 "github.com/filecoin-project/specs-actors/actors/builtin/cron"
-	init0 "github.com/filecoin-project/specs-actors/actors/builtin/init"
-	market0 "github.com/filecoin-project/specs-actors/actors/builtin/market"
-	miner0 "github.com/filecoin-project/specs-actors/actors/builtin/miner"
-	msig0 "github.com/filecoin-project/specs-actors/actors/builtin/multisig"
-	paych0 "github.com/filecoin-project/specs-actors/actors/builtin/paych"
-	power0 "github.com/filecoin-project/specs-actors/actors/builtin/power"
-	reward0 "github.com/filecoin-project/specs-actors/actors/builtin/reward"
-	verifreg0 "github.com/filecoin-project/specs-actors/actors/builtin/verifreg"
+	exported0 "github.com/filecoin-project/specs-actors/actors/builtin/exported"
 	proof0 "github.com/filecoin-project/specs-actors/actors/runtime/proof"
+	exported2 "github.com/filecoin-project/specs-actors/v2/actors/builtin/exported"

 	"github.com/filecoin-project/lotus/api"
-	"github.com/filecoin-project/lotus/build"
 	init_ "github.com/filecoin-project/lotus/chain/actors/builtin/init"
 	"github.com/filecoin-project/lotus/chain/actors/builtin/market"
 	"github.com/filecoin-project/lotus/chain/actors/builtin/miner"
@@ -102,6 +99,7 @@ func GetPowerRaw(ctx context.Context, sm *StateManager, st cid.Cid, maddr addres
 	}

 	var mpow power.Claim
+	var minpow bool
 	if maddr != address.Undef {
 		var found bool
 		mpow, found, err = pas.MinerPower(maddr)
@@ -109,11 +107,11 @@ func GetPowerRaw(ctx context.Context, sm *StateManager, st cid.Cid, maddr addres
 			// TODO: return an error when not found?
 			return power.Claim{}, power.Claim{}, false, err
 		}
-	}

-	minpow, err := pas.MinerNominalPowerMeetsConsensusMinimum(maddr)
-	if err != nil {
-		return power.Claim{}, power.Claim{}, false, err
+		minpow, err = pas.MinerNominalPowerMeetsConsensusMinimum(maddr)
+		if err != nil {
+			return power.Claim{}, power.Claim{}, false, err
+		}
 	}

 	return mpow, tpow, minpow, nil
@@ -368,6 +366,16 @@ func ComputeState(ctx context.Context, sm *StateManager, height abi.ChainEpoch,
 		return cid.Undef, nil, err
 	}

+	for i := ts.Height(); i < height; i++ {
+		// handle state forks
+		base, err = sm.handleStateForks(ctx, base, i, traceFunc(&trace), ts)
+		if err != nil {
+			return cid.Undef, nil, xerrors.Errorf("error handling state forks: %w", err)
+		}
+
+		// TODO: should we also run cron here?
+	}
+
 	r := store.NewChainRand(sm.cs, ts.Cids())
 	vmopt := &vm.VMOpts{
 		StateBase:      base,
@@ -379,21 +387,11 @@ func ComputeState(ctx context.Context, sm *StateManager, height abi.ChainEpoch,
 		NtwkVersion:    sm.GetNtwkVersion,
 		BaseFee:        ts.Blocks()[0].ParentBaseFee,
 	}
-	vmi, err := vm.NewVM(ctx, vmopt)
+	vmi, err := sm.newVM(ctx, vmopt)
 	if err != nil {
 		return cid.Undef, nil, err
 	}

-	for i := ts.Height(); i < height; i++ {
-		// handle state forks
-		err = sm.handleStateForks(ctx, vmi.StateTree(), i, ts)
-		if err != nil {
-			return cid.Undef, nil, xerrors.Errorf("error handling state forks: %w", err)
-		}
-
-		// TODO: should we also run cron here?
-	}
-
 	for i, msg := range msgs {
 		// TODO: Use the signed message length for secp messages
 		ret, err := vmi.ApplyMessage(ctx, msg)
@@ -415,8 +413,9 @@ func ComputeState(ctx context.Context, sm *StateManager, height abi.ChainEpoch,

 func GetLookbackTipSetForRound(ctx context.Context, sm *StateManager, ts *types.TipSet, round abi.ChainEpoch) (*types.TipSet, error) {
 	var lbr abi.ChainEpoch
-	if round > build.WinningPoStSectorSetLookback {
-		lbr = round - build.WinningPoStSectorSetLookback
+	lb := policy.GetWinningPoStSectorSetLookback(sm.GetNtwkVersion(ctx, round))
+	if round > lb {
+		lbr = round - lb
 	}

 	// more null blocks than our lookback
@@ -496,7 +495,7 @@ func MinerGetBaseInfo(ctx context.Context, sm *StateManager, bcs beacon.Schedule
 		return nil, nil
 	}

-	mpow, tpow, hmp, err := GetPowerRaw(ctx, sm, lbst, maddr)
+	mpow, tpow, _, err := GetPowerRaw(ctx, sm, lbst, maddr)
 	if err != nil {
 		return nil, xerrors.Errorf("failed to get power: %w", err)
 	}
@@ -511,15 +510,21 @@ func MinerGetBaseInfo(ctx context.Context, sm *StateManager, bcs beacon.Schedule
 		return nil, xerrors.Errorf("resolving worker address: %w", err)
 	}

+	// TODO: Not ideal performance...This method reloads miner and power state (already looked up here and in GetPowerRaw)
+	eligible, err := MinerEligibleToMine(ctx, sm, maddr, ts, lbts)
+	if err != nil {
+		return nil, xerrors.Errorf("determining miner eligibility: %w", err)
+	}
+
 	return &api.MiningBaseInfo{
-		MinerPower:      mpow.QualityAdjPower,
-		NetworkPower:    tpow.QualityAdjPower,
-		Sectors:         sectors,
-		WorkerKey:       worker,
-		SectorSize:      info.SectorSize,
-		PrevBeaconEntry: *prev,
-		BeaconEntries:   entries,
-		HasMinPower:     hmp,
+		MinerPower:        mpow.QualityAdjPower,
+		NetworkPower:      tpow.QualityAdjPower,
+		Sectors:           sectors,
+		WorkerKey:         worker,
+		SectorSize:        info.SectorSize,
+		PrevBeaconEntry:   *prev,
+		BeaconEntries:     entries,
+		EligibleForMining: eligible,
 	}, nil
 }

@@ -533,42 +538,23 @@ type MethodMeta struct {
 var MethodsMap = map[cid.Cid]map[abi.MethodNum]MethodMeta{}

 func init() {
-	cidToMethods := map[cid.Cid][2]interface{}{
-		// builtin.SystemActorCodeID:        {builtin.MethodsSystem, system.Actor{} }- apparently it doesn't have methods
-		builtin0.InitActorCodeID:             {builtin0.MethodsInit, init0.Actor{}},
-		builtin0.CronActorCodeID:             {builtin0.MethodsCron, cron0.Actor{}},
-		builtin0.AccountActorCodeID:          {builtin0.MethodsAccount, account0.Actor{}},
-		builtin0.StoragePowerActorCodeID:     {builtin0.MethodsPower, power0.Actor{}},
-		builtin0.StorageMinerActorCodeID:     {builtin0.MethodsMiner, miner0.Actor{}},
-		builtin0.StorageMarketActorCodeID:    {builtin0.MethodsMarket, market0.Actor{}},
-		builtin0.PaymentChannelActorCodeID:   {builtin0.MethodsPaych, paych0.Actor{}},
-		builtin0.MultisigActorCodeID:         {builtin0.MethodsMultisig, msig0.Actor{}},
-		builtin0.RewardActorCodeID:           {builtin0.MethodsReward, reward0.Actor{}},
-		builtin0.VerifiedRegistryActorCodeID: {builtin0.MethodsVerifiedRegistry, verifreg0.Actor{}},
-	}
+	// TODO: combine with the runtime actor registry.
+	var actors []rt.VMActor
+	actors = append(actors, exported0.BuiltinActors()...)
+	actors = append(actors, exported2.BuiltinActors()...)

-	for c, m := range cidToMethods {
-		exports := m[1].(vm.Invokee).Exports()
+	for _, actor := range actors {
+		exports := actor.Exports()
 		methods := make(map[abi.MethodNum]MethodMeta, len(exports))

 		// Explicitly add send, it's special.
+		// Note that builtin2.MethodSend = builtin0.MethodSend = 0.
 		methods[builtin0.MethodSend] = MethodMeta{
 			Name:   "Send",
 			Params: reflect.TypeOf(new(abi.EmptyValue)),
 			Ret:    reflect.TypeOf(new(abi.EmptyValue)),
 		}

-		// Learn method names from the builtin.Methods* structs.
-		rv := reflect.ValueOf(m[0])
-		rt := rv.Type()
-		nf := rt.NumField()
-		methodToName := make([]string, len(exports))
-		for i := 0; i < nf; i++ {
-			name := rt.Field(i).Name
-			number := rv.Field(i).Interface().(abi.MethodNum)
-			methodToName[number] = name
-		}
-
 		// Iterate over exported methods. Some of these _may_ be nil and
 		// must be skipped.
 		for number, export := range exports {
@@ -579,22 +565,19 @@ func init() {
 			ev := reflect.ValueOf(export)
 			et := ev.Type()

-			// Make sure the method name is correct.
-			// This is just a nice sanity check.
+			// Extract the method names using reflection. These
+			// method names always match the field names in the
+			// `builtin.Method*` structs (tested in the specs-actors
+			// tests).
 			fnName := runtime.FuncForPC(ev.Pointer()).Name()
 			fnName = strings.TrimSuffix(fnName[strings.LastIndexByte(fnName, '.')+1:], "-fm")
-			mName := methodToName[number]
-			if mName != fnName {
-				panic(fmt.Sprintf(
-					"actor method name is %s but exported method name is %s",
-					fnName, mName,
-				))
-			}

 			switch abi.MethodNum(number) {
 			case builtin0.MethodSend:
+				// Note that builtin2.MethodSend = builtin0.MethodSend = 0.
 				panic("method 0 is reserved for Send")
 			case builtin0.MethodConstructor:
+				// Note that builtin2.MethodConstructor = builtin0.MethodConstructor = 1.
 				if fnName != "Constructor" {
 					panic("method 1 is reserved for Constructor")
 				}
@@ -606,7 +589,7 @@ func init() {
 				Ret:    et.Out(0),
 			}
 		}
-		MethodsMap[c] = methods
+		MethodsMap[actor.Code()] = methods
 	}
 }

@@ -623,7 +606,7 @@ func GetReturnType(ctx context.Context, sm *StateManager, to address.Address, me
 	return reflect.New(m.Ret.Elem()).Interface().(cbg.CBORUnmarshaler), nil
 }

-func MinerHasMinPower(ctx context.Context, sm *StateManager, addr address.Address, ts *types.TipSet) (bool, error) {
+func minerHasMinPower(ctx context.Context, sm *StateManager, addr address.Address, ts *types.TipSet) (bool, error) {
 	pact, err := sm.LoadActor(ctx, power.Address, ts)
 	if err != nil {
 		return false, xerrors.Errorf("loading power actor state: %w", err)
@@ -637,6 +620,70 @@ func MinerHasMinPower(ctx context.Context, sm *StateManager, addr address.Addres
 	return ps.MinerNominalPowerMeetsConsensusMinimum(addr)
 }

+func MinerEligibleToMine(ctx context.Context, sm *StateManager, addr address.Address, baseTs *types.TipSet, lookbackTs *types.TipSet) (bool, error) {
+	hmp, err := minerHasMinPower(ctx, sm, addr, lookbackTs)
+
+	// TODO: We're blurring the lines between a "runtime network version" and a "Lotus upgrade epoch", is that unavoidable?
+	if sm.GetNtwkVersion(ctx, baseTs.Height()) <= network.Version3 {
+		return hmp, err
+	}
+
+	if err != nil {
+		return false, err
+	}
+
+	if !hmp {
+		return false, nil
+	}
+
+	// Post actors v2, also check MinerEligibleForElection with base ts
+
+	pact, err := sm.LoadActor(ctx, power.Address, baseTs)
+	if err != nil {
+		return false, xerrors.Errorf("loading power actor state: %w", err)
+	}
+
+	pstate, err := power.Load(sm.cs.Store(ctx), pact)
+	if err != nil {
+		return false, err
+	}
+
+	mact, err := sm.LoadActor(ctx, addr, baseTs)
+	if err != nil {
+		return false, xerrors.Errorf("loading miner actor state: %w", err)
+	}
+
+	mstate, err := miner.Load(sm.cs.Store(ctx), mact)
+	if err != nil {
+		return false, err
+	}
+
+	// Non-empty power claim.
+	if claim, found, err := pstate.MinerPower(addr); err != nil {
+		return false, err
+	} else if !found {
+		return false, err
+	} else if claim.QualityAdjPower.LessThanEqual(big.Zero()) {
+		return false, err
+	}
+
+	// No fee debt.
+	if debt, err := mstate.FeeDebt(); err != nil {
+		return false, err
+	} else if !debt.IsZero() {
+		return false, err
+	}
+
+	// No active consensus faults.
+	if mInfo, err := mstate.Info(); err != nil {
+		return false, err
+	} else if baseTs.Height() <= mInfo.ConsensusFaultElapsed {
+		return false, nil
+	}
+
+	return true, nil
+}
+
 func CheckTotalFIL(ctx context.Context, sm *StateManager, ts *types.TipSet) (abi.TokenAmount, error) {
 	str, err := state.LoadStateTree(sm.ChainStore().Store(ctx), ts.ParentState())
 	if err != nil {
@@ -46,7 +46,7 @@ func ComputeNextBaseFee(baseFee types.BigInt, gasLimitUsed int64, noOfBlocks int
 }

 func (cs *ChainStore) ComputeBaseFee(ctx context.Context, ts *types.TipSet) (abi.TokenAmount, error) {
-	if ts.Height() > build.UpgradeBreezeHeight && ts.Height() < build.UpgradeBreezeHeight+build.BreezeGasTampingDuration {
+	if build.UpgradeBreezeHeight >= 0 && ts.Height() > build.UpgradeBreezeHeight && ts.Height() < build.UpgradeBreezeHeight+build.BreezeGasTampingDuration {
 		return abi.NewTokenAmount(100), nil
 	}

@@ -11,24 +11,27 @@ import (

 func TestBaseFee(t *testing.T) {
 	tests := []struct {
-		basefee    uint64
-		limitUsed  int64
-		noOfBlocks int
-		output     uint64
+		basefee             uint64
+		limitUsed           int64
+		noOfBlocks          int
+		preSmoke, postSmoke uint64
 	}{
-		{100e6, 0, 1, 87.5e6},
-		{100e6, 0, 5, 87.5e6},
-		{100e6, build.BlockGasTarget, 1, 103.125e6},
-		{100e6, build.BlockGasTarget * 2, 2, 103.125e6},
-		{100e6, build.BlockGasLimit * 2, 2, 112.5e6},
-		{100e6, build.BlockGasLimit * 1.5, 2, 110937500},
+		{100e6, 0, 1, 87.5e6, 87.5e6},
+		{100e6, 0, 5, 87.5e6, 87.5e6},
+		{100e6, build.BlockGasTarget, 1, 103.125e6, 100e6},
+		{100e6, build.BlockGasTarget * 2, 2, 103.125e6, 100e6},
+		{100e6, build.BlockGasLimit * 2, 2, 112.5e6, 112.5e6},
+		{100e6, build.BlockGasLimit * 1.5, 2, 110937500, 106.250e6},
 	}

 	for _, test := range tests {
 		test := test
 		t.Run(fmt.Sprintf("%v", test), func(t *testing.T) {
-			output := ComputeNextBaseFee(types.NewInt(test.basefee), test.limitUsed, test.noOfBlocks, 0)
-			assert.Equal(t, fmt.Sprintf("%d", test.output), output.String())
+			preSmoke := ComputeNextBaseFee(types.NewInt(test.basefee), test.limitUsed, test.noOfBlocks, build.UpgradeSmokeHeight-1)
+			assert.Equal(t, fmt.Sprintf("%d", test.preSmoke), preSmoke.String())
+
+			postSmoke := ComputeNextBaseFee(types.NewInt(test.basefee), test.limitUsed, test.noOfBlocks, build.UpgradeSmokeHeight+1)
+			assert.Equal(t, fmt.Sprintf("%d", test.postSmoke), postSmoke.String())
 		})
 	}
 }
@@ -10,14 +10,20 @@ import (
 	"strconv"
 	"sync"

+	"golang.org/x/sync/errgroup"
+
 	"github.com/filecoin-project/go-state-types/crypto"
 	"github.com/minio/blake2b-simd"

 	"github.com/filecoin-project/go-address"
 	"github.com/filecoin-project/go-state-types/abi"
-	"github.com/filecoin-project/specs-actors/actors/util/adt"
+
+	"github.com/filecoin-project/specs-actors/actors/builtin"
+	adt0 "github.com/filecoin-project/specs-actors/actors/util/adt"

 	"github.com/filecoin-project/lotus/api"
+	"github.com/filecoin-project/lotus/build"
+	"github.com/filecoin-project/lotus/chain/actors/adt"
 	"github.com/filecoin-project/lotus/chain/vm"
 	"github.com/filecoin-project/lotus/journal"
 	bstore "github.com/filecoin-project/lotus/lib/blockstore"
@@ -282,6 +288,16 @@ func (cs *ChainStore) MarkBlockAsValidated(ctx context.Context, blkid cid.Cid) e
 	return nil
 }

+func (cs *ChainStore) UnmarkBlockAsValidated(ctx context.Context, blkid cid.Cid) error {
+	key := blockValidationCacheKeyPrefix.Instance(blkid.String())
+
+	if err := cs.ds.Delete(key); err != nil {
+		return xerrors.Errorf("removing from valid block cache: %w", err)
+	}
+
+	return nil
+}
+
 func (cs *ChainStore) SetGenesis(b *types.BlockHeader) error {
 	ts, err := types.NewTipSet([]*types.BlockHeader{b})
 	if err != nil {
@@ -465,14 +481,25 @@ func (cs *ChainStore) LoadTipSet(tsk types.TipSetKey) (*types.TipSet, error) {
 		return v.(*types.TipSet), nil
 	}

-	var blks []*types.BlockHeader
-	for _, c := range tsk.Cids() {
-		b, err := cs.GetBlock(c)
-		if err != nil {
-			return nil, xerrors.Errorf("get block %s: %w", c, err)
-		}
+	// Fetch tipset block headers from blockstore in parallel
+	var eg errgroup.Group
+	cids := tsk.Cids()
+	blks := make([]*types.BlockHeader, len(cids))
+	for i, c := range cids {
+		i, c := i, c
+		eg.Go(func() error {
+			b, err := cs.GetBlock(c)
+			if err != nil {
+				return xerrors.Errorf("get block %s: %w", c, err)
+			}

-		blks = append(blks, b)
+			blks[i] = b
+			return nil
+		})
+	}
+	err := eg.Wait()
+	if err != nil {
+		return nil, err
 	}

 	ts, err := types.NewTipSet(blks)
@@ -732,7 +759,8 @@ func (cs *ChainStore) GetSignedMessage(c cid.Cid) (*types.SignedMessage, error)

 func (cs *ChainStore) readAMTCids(root cid.Cid) ([]cid.Cid, error) {
 	ctx := context.TODO()
-	a, err := adt.AsArray(cs.Store(ctx), root)
+	// block headers use adt0, for now.
+	a, err := adt0.AsArray(cs.Store(ctx), root)
 	if err != nil {
 		return nil, xerrors.Errorf("amt load: %w", err)
 	}
@@ -925,7 +953,8 @@ func (cs *ChainStore) MessagesForBlock(b *types.BlockHeader) ([]*types.Message,

 func (cs *ChainStore) GetParentReceipt(b *types.BlockHeader, i int) (*types.MessageReceipt, error) {
 	ctx := context.TODO()
-	a, err := adt.AsArray(cs.Store(ctx), b.ParentMessageReceipts)
+	// block headers use adt0, for now.
+	a, err := adt0.AsArray(cs.Store(ctx), b.ParentMessageReceipts)
 	if err != nil {
 		return nil, xerrors.Errorf("amt load: %w", err)
 	}
@@ -1166,13 +1195,6 @@ func recurseLinks(bs bstore.Blockstore, walked *cid.Set, root cid.Cid, in []cid.
 }

 func (cs *ChainStore) Export(ctx context.Context, ts *types.TipSet, inclRecentRoots abi.ChainEpoch, skipOldMsgs bool, w io.Writer) error {
-	if ts == nil {
-		ts = cs.GetHeaviestTipSet()
-	}
-
-	seen := cid.NewSet()
-	walked := cid.NewSet()
-
 	h := &car.CarHeader{
 		Roots:   ts.Cids(),
 		Version: 1,
@@ -1182,27 +1204,57 @@ func (cs *ChainStore) Export(ctx context.Context, ts *types.TipSet, inclRecentRo
 		return xerrors.Errorf("failed to write car header: %s", err)
 	}

+	return cs.WalkSnapshot(ctx, ts, inclRecentRoots, skipOldMsgs, func(c cid.Cid) error {
+		blk, err := cs.bs.Get(c)
+		if err != nil {
+			return xerrors.Errorf("writing object to car, bs.Get: %w", err)
+		}
+
+		if err := carutil.LdWrite(w, c.Bytes(), blk.RawData()); err != nil {
+			return xerrors.Errorf("failed to write block to car output: %w", err)
+		}
+
+		return nil
+	})
+}
+
+func (cs *ChainStore) WalkSnapshot(ctx context.Context, ts *types.TipSet, inclRecentRoots abi.ChainEpoch, skipOldMsgs bool, cb func(cid.Cid) error) error {
+	if ts == nil {
+		ts = cs.GetHeaviestTipSet()
+	}
+
+	seen := cid.NewSet()
+	walked := cid.NewSet()
+
 	blocksToWalk := ts.Cids()
+	currentMinHeight := ts.Height()

 	walkChain := func(blk cid.Cid) error {
 		if !seen.Visit(blk) {
 			return nil
 		}

+		if err := cb(blk); err != nil {
+			return err
+		}
+
 		data, err := cs.bs.Get(blk)
 		if err != nil {
 			return xerrors.Errorf("getting block: %w", err)
 		}

-		if err := carutil.LdWrite(w, blk.Bytes(), data.RawData()); err != nil {
-			return xerrors.Errorf("failed to write block to car output: %w", err)
-		}
-
 		var b types.BlockHeader
 		if err := b.UnmarshalCBOR(bytes.NewBuffer(data.RawData())); err != nil {
 			return xerrors.Errorf("unmarshaling block header (cid=%s): %w", blk, err)
 		}

+		if currentMinHeight > b.Height {
+			currentMinHeight = b.Height
+			if currentMinHeight%builtin.EpochsInDay == 0 {
+				log.Infow("export", "height", currentMinHeight)
+			}
+		}
+
 		var cids []cid.Cid
 		if !skipOldMsgs || b.Height > ts.Height()-inclRecentRoots {
 			mcids, err := recurseLinks(cs.bs, walked, b.Messages, []cid.Cid{b.Messages})
@@ -1237,20 +1289,20 @@ func (cs *ChainStore) Export(ctx context.Context, ts *types.TipSet, inclRecentRo
 				if c.Prefix().Codec != cid.DagCBOR {
 					continue
 				}
-				data, err := cs.bs.Get(c)
-				if err != nil {
-					return xerrors.Errorf("writing object to car (get %s): %w", c, err)
+
+				if err := cb(c); err != nil {
+					return err
 				}

-				if err := carutil.LdWrite(w, c.Bytes(), data.RawData()); err != nil {
-					return xerrors.Errorf("failed to write out car object: %w", err)
-				}
 			}
 		}

 		return nil
 	}

+	log.Infow("export started")
+	exportStart := build.Clock.Now()
+
 	for len(blocksToWalk) > 0 {
 		next := blocksToWalk[0]
 		blocksToWalk = blocksToWalk[1:]
@@ -1259,6 +1311,8 @@ func (cs *ChainStore) Export(ctx context.Context, ts *types.TipSet, inclRecentRo
 		}
 	}

+	log.Infow("export finished", "duration", build.Clock.Now().Sub(exportStart).Seconds())
+
 	return nil
 }

@@ -1301,7 +1355,7 @@ func (cs *ChainStore) GetLatestBeaconEntry(ts *types.TipSet) (*types.BeaconEntry
 		}, nil
 	}

-	return nil, xerrors.Errorf("found NO beacon entries in the 20 blocks prior to given tipset")
+	return nil, xerrors.Errorf("found NO beacon entries in the 20 latest tipsets")
 }

 type chainRand struct {
@@ -8,12 +8,9 @@ import (
 	datastore "github.com/ipfs/go-datastore"

 	"github.com/filecoin-project/go-state-types/abi"
-	"github.com/filecoin-project/go-state-types/big"
 	"github.com/filecoin-project/go-state-types/crypto"
-	miner0 "github.com/filecoin-project/specs-actors/actors/builtin/miner"
-	power0 "github.com/filecoin-project/specs-actors/actors/builtin/power"
-	verifreg0 "github.com/filecoin-project/specs-actors/actors/builtin/verifreg"

+	"github.com/filecoin-project/lotus/chain/actors/policy"
 	"github.com/filecoin-project/lotus/chain/gen"
 	"github.com/filecoin-project/lotus/chain/store"
 	"github.com/filecoin-project/lotus/chain/types"
@@ -22,11 +19,9 @@ import (
 )

 func init() {
-	miner0.SupportedProofTypes = map[abi.RegisteredSealProof]struct{}{
-		abi.RegisteredSealProof_StackedDrg2KiBV1: {},
-	}
-	power0.ConsensusMinerMinPower = big.NewInt(2048)
-	verifreg0.MinVerifiedDealSize = big.NewInt(256)
+	policy.SetSupportedProofTypes(abi.RegisteredSealProof_StackedDrg2KiBV1)
+	policy.SetConsensusMinerMinPower(abi.NewStoragePower(2048))
+	policy.SetMinVerifiedDealSize(abi.NewStoragePower(256))
 }

 func BenchmarkGetRandomness(b *testing.B) {
@@ -10,7 +10,6 @@ import (
 	"golang.org/x/xerrors"

 	address "github.com/filecoin-project/go-address"
-	"github.com/filecoin-project/specs-actors/actors/util/adt"
 	lru "github.com/hashicorp/golang-lru"
 	blocks "github.com/ipfs/go-block-format"
 	bserv "github.com/ipfs/go-blockservice"
@@ -24,6 +23,8 @@ import (
 	"go.opencensus.io/stats"
 	"go.opencensus.io/tag"

+	adt0 "github.com/filecoin-project/specs-actors/actors/util/adt"
+
 	"github.com/filecoin-project/lotus/build"
 	"github.com/filecoin-project/lotus/chain"
 	"github.com/filecoin-project/lotus/chain/actors/builtin/miner"
@@ -43,7 +44,11 @@ var log = logging.Logger("sub")
 var ErrSoftFailure = errors.New("soft validation failure")
 var ErrInsufficientPower = errors.New("incoming block's miner does not have minimum power")

-func HandleIncomingBlocks(ctx context.Context, bsub *pubsub.Subscription, s *chain.Syncer, bserv bserv.BlockService, cmgr connmgr.ConnManager) {
+func HandleIncomingBlocks(ctx context.Context, bsub *pubsub.Subscription, s *chain.Syncer, bs bserv.BlockService, cmgr connmgr.ConnManager) {
+	// Timeout after (block time + propagation delay). This is useless at
+	// this point.
+	timeout := time.Duration(build.BlockDelaySecs+build.PropagationDelaySecs) * time.Second
+
 	for {
 		msg, err := bsub.Next(ctx)
 		if err != nil {
@@ -64,15 +69,22 @@ func HandleIncomingBlocks(ctx context.Context, bsub *pubsub.Subscription, s *cha
 		src := msg.GetFrom()

 		go func() {
+			ctx, cancel := context.WithTimeout(ctx, timeout)
+			defer cancel()
+
+			// NOTE: we could also share a single session between
+			// all requests but that may have other consequences.
+			ses := bserv.NewSession(ctx, bs)
+
 			start := build.Clock.Now()
 			log.Debug("about to fetch messages for block from pubsub")
-			bmsgs, err := FetchMessagesByCids(context.TODO(), bserv, blk.BlsMessages)
+			bmsgs, err := FetchMessagesByCids(ctx, ses, blk.BlsMessages)
 			if err != nil {
 				log.Errorf("failed to fetch all bls messages for block received over pubusb: %s; source: %s", err, src)
 				return
 			}

-			smsgs, err := FetchSignedMessagesByCids(context.TODO(), bserv, blk.SecpkMessages)
+			smsgs, err := FetchSignedMessagesByCids(ctx, ses, blk.SecpkMessages)
 			if err != nil {
 				log.Errorf("failed to fetch all secpk messages for block received over pubusb: %s; source: %s", err, src)
 				return
@@ -97,7 +109,7 @@ func HandleIncomingBlocks(ctx context.Context, bsub *pubsub.Subscription, s *cha

 func FetchMessagesByCids(
 	ctx context.Context,
-	bserv bserv.BlockService,
+	bserv bserv.BlockGetter,
 	cids []cid.Cid,
 ) ([]*types.Message, error) {
 	out := make([]*types.Message, len(cids))
@@ -126,7 +138,7 @@ func FetchMessagesByCids(
 // FIXME: Duplicate of above.
 func FetchSignedMessagesByCids(
 	ctx context.Context,
-	bserv bserv.BlockService,
+	bserv bserv.BlockGetter,
 	cids []cid.Cid,
 ) ([]*types.SignedMessage, error) {
 	out := make([]*types.SignedMessage, len(cids))
@@ -156,12 +168,11 @@ func FetchSignedMessagesByCids(
 //  blocks we did not request.
 func fetchCids(
 	ctx context.Context,
-	bserv bserv.BlockService,
+	bserv bserv.BlockGetter,
 	cids []cid.Cid,
 	cb func(int, blocks.Block) error,
 ) error {
-	// FIXME: Why don't we use the context here?
-	fetchedBlocks := bserv.GetBlocks(context.TODO(), cids)
+	fetchedBlocks := bserv.GetBlocks(ctx, cids)

 	cidIndex := make(map[cid.Cid]int)
 	for i, c := range cids {
@@ -374,9 +385,10 @@ func (bv *BlockValidator) isChainNearSynced() bool {

 func (bv *BlockValidator) validateMsgMeta(ctx context.Context, msg *types.BlockMsg) error {
 	// TODO there has to be a simpler way to do this without the blockstore dance
-	store := adt.WrapStore(ctx, cbor.NewCborStore(blockstore.NewTemporary()))
-	bmArr := adt.MakeEmptyArray(store)
-	smArr := adt.MakeEmptyArray(store)
+	// block headers use adt0
+	store := adt0.WrapStore(ctx, cbor.NewCborStore(blockstore.NewTemporary()))
+	bmArr := adt0.MakeEmptyArray(store)
+	smArr := adt0.MakeEmptyArray(store)

 	for i, m := range msg.BlsMessages {
 		c := cbg.CborCid(m)
@@ -473,14 +485,14 @@ func (bv *BlockValidator) checkPowerAndGetWorkerKey(ctx context.Context, bh *typ
 		return address.Undef, ErrSoftFailure
 	}

-	hmp, err := stmgr.MinerHasMinPower(ctx, bv.stmgr, bh.Miner, lbts)
+	eligible, err := stmgr.MinerEligibleToMine(ctx, bv.stmgr, bh.Miner, baseTs, lbts)
 	if err != nil {
 		log.Warnf("failed to determine if incoming block's miner has minimum power: %s", err)
 		return address.Undef, ErrSoftFailure
 	}

-	if !hmp {
-		log.Warnf("incoming block's miner does not have minimum power")
+	if !eligible {
+		log.Warnf("incoming block's miner is ineligible")
 		return address.Undef, ErrInsufficientPower
 	}

@@ -11,12 +11,15 @@ import (
 	"sync"
 	"time"

+	"github.com/filecoin-project/lotus/chain/actors/builtin"
+
 	"github.com/filecoin-project/lotus/node/modules/dtypes"

 	"github.com/filecoin-project/specs-actors/actors/runtime/proof"

 	"github.com/Gurpartap/async"
 	"github.com/hashicorp/go-multierror"
+	blocks "github.com/ipfs/go-block-format"
 	"github.com/ipfs/go-cid"
 	cbor "github.com/ipfs/go-ipld-cbor"
 	logging "github.com/ipfs/go-log/v2"
@@ -32,9 +35,10 @@ import (
 	"github.com/filecoin-project/go-state-types/abi"
 	"github.com/filecoin-project/go-state-types/crypto"
 	"github.com/filecoin-project/lotus/extern/sector-storage/ffiwrapper"
-	"github.com/filecoin-project/specs-actors/actors/util/adt"
 	blst "github.com/supranational/blst/bindings/go"

+	adt0 "github.com/filecoin-project/specs-actors/actors/util/adt"
+
 	"github.com/filecoin-project/lotus/api"
 	"github.com/filecoin-project/lotus/build"
 	"github.com/filecoin-project/lotus/chain/actors/builtin/power"
@@ -374,21 +378,28 @@ func (syncer *Syncer) InformNewBlock(from peer.ID, blk *types.FullBlock) bool {
 	return syncer.InformNewHead(from, fts)
 }

-func copyBlockstore(from, to bstore.Blockstore) error {
-	cids, err := from.AllKeysChan(context.TODO())
+func copyBlockstore(ctx context.Context, from, to bstore.Blockstore) error {
+	ctx, span := trace.StartSpan(ctx, "copyBlockstore")
+	defer span.End()
+
+	cids, err := from.AllKeysChan(ctx)
 	if err != nil {
 		return err
 	}

+	// TODO: should probably expose better methods on the blockstore for this operation
+	var blks []blocks.Block
 	for c := range cids {
 		b, err := from.Get(c)
 		if err != nil {
 			return err
 		}

-		if err := to.Put(b); err != nil {
-			return err
-		}
+		blks = append(blks, b)
+	}
+
+	if err := to.PutMany(blks); err != nil {
+		return err
 	}

 	return nil
@@ -447,9 +458,10 @@ func zipTipSetAndMessages(bs cbor.IpldStore, ts *types.TipSet, allbmsgs []*types
 // computeMsgMeta computes the root CID of the combined arrays of message CIDs
 // of both types (BLS and Secpk).
 func computeMsgMeta(bs cbor.IpldStore, bmsgCids, smsgCids []cid.Cid) (cid.Cid, error) {
-	store := adt.WrapStore(context.TODO(), bs)
-	bmArr := adt.MakeEmptyArray(store)
-	smArr := adt.MakeEmptyArray(store)
+	// block headers use adt0
+	store := adt0.WrapStore(context.TODO(), bs)
+	bmArr := adt0.MakeEmptyArray(store)
+	smArr := adt0.MakeEmptyArray(store)

 	for i, m := range bmsgCids {
 		c := cbg.CborCid(m)
@@ -589,7 +601,7 @@ func isPermanent(err error) bool {
 	return !errors.Is(err, ErrTemporal)
 }

-func (syncer *Syncer) ValidateTipSet(ctx context.Context, fts *store.FullTipSet) error {
+func (syncer *Syncer) ValidateTipSet(ctx context.Context, fts *store.FullTipSet, useCache bool) error {
 	ctx, span := trace.StartSpan(ctx, "validateTipSet")
 	defer span.End()

@@ -605,7 +617,7 @@ func (syncer *Syncer) ValidateTipSet(ctx context.Context, fts *store.FullTipSet)
 		b := b // rebind to a scoped variable

 		futures = append(futures, async.Err(func() error {
-			if err := syncer.ValidateBlock(ctx, b); err != nil {
+			if err := syncer.ValidateBlock(ctx, b, useCache); err != nil {
 				if isPermanent(err) {
 					syncer.bad.Add(b.Cid(), NewBadBlockReason([]cid.Cid{b.Cid()}, err.Error()))
 				}
@@ -672,7 +684,7 @@ func blockSanityChecks(h *types.BlockHeader) error {
 }

 // ValidateBlock should match up with 'Semantical Validation' in validation.md in the spec
-func (syncer *Syncer) ValidateBlock(ctx context.Context, b *types.FullBlock) (err error) {
+func (syncer *Syncer) ValidateBlock(ctx context.Context, b *types.FullBlock, useCache bool) (err error) {
 	defer func() {
 		// b.Cid() could panic for empty blocks that are used in tests.
 		if rerr := recover(); rerr != nil {
@@ -681,13 +693,15 @@ func (syncer *Syncer) ValidateBlock(ctx context.Context, b *types.FullBlock) (er
 		}
 	}()

-	isValidated, err := syncer.store.IsBlockValidated(ctx, b.Cid())
-	if err != nil {
-		return xerrors.Errorf("check block validation cache %s: %w", b.Cid(), err)
-	}
+	if useCache {
+		isValidated, err := syncer.store.IsBlockValidated(ctx, b.Cid())
+		if err != nil {
+			return xerrors.Errorf("check block validation cache %s: %w", b.Cid(), err)
+		}

-	if isValidated {
-		return nil
+		if isValidated {
+			return nil
+		}
 	}

 	validationStart := build.Clock.Now()
@@ -774,31 +788,35 @@ func (syncer *Syncer) ValidateBlock(ctx context.Context, b *types.FullBlock) (er
 			b.Header.ParentWeight, pweight)
 	}

-	// Stuff that needs stateroot / worker address
-	stateroot, precp, err := syncer.sm.TipSetState(ctx, baseTs)
-	if err != nil {
-		return xerrors.Errorf("get tipsetstate(%d, %s) failed: %w", h.Height, h.Parents, err)
-	}
-
-	if stateroot != h.ParentStateRoot {
-		msgs, err := syncer.store.MessagesForTipset(baseTs)
+	stateRootCheck := async.Err(func() error {
+		stateroot, precp, err := syncer.sm.TipSetState(ctx, baseTs)
 		if err != nil {
-			log.Error("failed to load messages for tipset during tipset state mismatch error: ", err)
-		} else {
-			log.Warn("Messages for tipset with mismatching state:")
-			for i, m := range msgs {
-				mm := m.VMMessage()
-				log.Warnf("Message[%d]: from=%s to=%s method=%d params=%x", i, mm.From, mm.To, mm.Method, mm.Params)
-			}
+			return xerrors.Errorf("get tipsetstate(%d, %s) failed: %w", h.Height, h.Parents, err)
 		}

-		return xerrors.Errorf("parent state root did not match computed state (%s != %s)", stateroot, h.ParentStateRoot)
-	}
+		if stateroot != h.ParentStateRoot {
+			msgs, err := syncer.store.MessagesForTipset(baseTs)
+			if err != nil {
+				log.Error("failed to load messages for tipset during tipset state mismatch error: ", err)
+			} else {
+				log.Warn("Messages for tipset with mismatching state:")
+				for i, m := range msgs {
+					mm := m.VMMessage()
+					log.Warnf("Message[%d]: from=%s to=%s method=%d params=%x", i, mm.From, mm.To, mm.Method, mm.Params)
+				}
+			}

-	if precp != h.ParentMessageReceipts {
-		return xerrors.Errorf("parent receipts root did not match computed value (%s != %s)", precp, h.ParentMessageReceipts)
-	}
+			return xerrors.Errorf("parent state root did not match computed state (%s != %s)", stateroot, h.ParentStateRoot)
+		}

+		if precp != h.ParentMessageReceipts {
+			return xerrors.Errorf("parent receipts root did not match computed value (%s != %s)", precp, h.ParentMessageReceipts)
+		}
+
+		return nil
+	})
+
+	// Stuff that needs worker address
 	waddr, err := stmgr.GetMinerWorkerRaw(ctx, syncer.sm, lbst, h.Miner)
 	if err != nil {
 		return xerrors.Errorf("GetMinerWorkerRaw failed: %w", err)
@@ -809,13 +827,13 @@ func (syncer *Syncer) ValidateBlock(ctx context.Context, b *types.FullBlock) (er
 			return xerrors.Errorf("block is not claiming to be a winner")
 		}

-		hp, err := stmgr.MinerHasMinPower(ctx, syncer.sm, h.Miner, lbts)
+		eligible, err := stmgr.MinerEligibleToMine(ctx, syncer.sm, h.Miner, baseTs, lbts)
 		if err != nil {
 			return xerrors.Errorf("determining if miner has min power failed: %w", err)
 		}

-		if !hp {
-			return xerrors.New("block's miner does not meet minimum power threshold")
+		if !eligible {
+			return xerrors.New("block's miner is ineligible to mine")
 		}

 		rBeacon := *prevBeacon
@@ -919,6 +937,7 @@ func (syncer *Syncer) ValidateBlock(ctx context.Context, b *types.FullBlock) (er
 		winnerCheck,
 		msgsCheck,
 		baseFeeCheck,
+		stateRootCheck,
 	}

 	var merr error
@@ -946,8 +965,10 @@ func (syncer *Syncer) ValidateBlock(ctx context.Context, b *types.FullBlock) (er
 		return mulErr
 	}

-	if err := syncer.store.MarkBlockAsValidated(ctx, b.Cid()); err != nil {
-		return xerrors.Errorf("caching block validation %s: %w", b.Cid(), err)
+	if useCache {
+		if err := syncer.store.MarkBlockAsValidated(ctx, b.Cid()); err != nil {
+			return xerrors.Errorf("caching block validation %s: %w", b.Cid(), err)
+		}
 	}

 	return nil
@@ -1070,7 +1091,7 @@ func (syncer *Syncer) checkBlockMessages(ctx context.Context, b *types.FullBlock
 				return xerrors.Errorf("failed to get actor: %w", err)
 			}

-			if !act.IsAccountActor() {
+			if !builtin.IsAccountActor(act.Code) {
 				return xerrors.New("Sender must be an account actor")
 			}
 			nonces[m.From] = act.Nonce
@@ -1084,9 +1105,9 @@ func (syncer *Syncer) checkBlockMessages(ctx context.Context, b *types.FullBlock
 		return nil
 	}

-	store := adt.WrapStore(ctx, cst)
+	store := adt0.WrapStore(ctx, cst)

-	bmArr := adt.MakeEmptyArray(store)
+	bmArr := adt0.MakeEmptyArray(store)
 	for i, m := range b.BlsMessages {
 		if err := checkMsg(m); err != nil {
 			return xerrors.Errorf("block had invalid bls message at index %d: %w", i, err)
@@ -1098,7 +1119,7 @@ func (syncer *Syncer) checkBlockMessages(ctx context.Context, b *types.FullBlock
 		}
 	}

-	smArr := adt.MakeEmptyArray(store)
+	smArr := adt0.MakeEmptyArray(store)
 	for i, m := range b.SecpkMessages {
 		if err := checkMsg(m); err != nil {
 			return xerrors.Errorf("block had invalid secpk message at index %d: %w", i, err)
@@ -1449,7 +1470,7 @@ func (syncer *Syncer) syncMessagesAndCheckState(ctx context.Context, headers []*

 	return syncer.iterFullTipsets(ctx, headers, func(ctx context.Context, fts *store.FullTipSet) error {
 		log.Debugw("validating tipset", "height", fts.TipSet().Height(), "size", len(fts.TipSet().Cids()))
-		if err := syncer.ValidateTipSet(ctx, fts); err != nil {
+		if err := syncer.ValidateTipSet(ctx, fts, true); err != nil {
 			log.Errorf("failed to validate tipset: %+v", err)
 			return xerrors.Errorf("message processing failed: %w", err)
 		}
@@ -1515,11 +1536,11 @@ func (syncer *Syncer) iterFullTipsets(ctx context.Context, headers []*types.TipS
 				return err
 			}

-			if err := persistMessages(bs, bstip); err != nil {
+			if err := persistMessages(ctx, bs, bstip); err != nil {
 				return err
 			}

-			if err := copyBlockstore(bs, syncer.store.Blockstore()); err != nil {
+			if err := copyBlockstore(ctx, bs, syncer.store.Blockstore()); err != nil {
 				return xerrors.Errorf("message processing failed: %w", err)
 			}
 		}
@@ -1596,7 +1617,10 @@ func (syncer *Syncer) fetchMessages(ctx context.Context, headers []*types.TipSet
 	return batch, nil
 }

-func persistMessages(bs bstore.Blockstore, bst *exchange.CompactedMessages) error {
+func persistMessages(ctx context.Context, bs bstore.Blockstore, bst *exchange.CompactedMessages) error {
+	_, span := trace.StartSpan(ctx, "persistMessages")
+	defer span.End()
+
 	for _, m := range bst.Bls {
 		//log.Infof("putting BLS message: %s", m.Cid())
 		if _, err := store.PutMessage(bs, m); err != nil {
@@ -1728,7 +1752,7 @@ func (syncer *Syncer) getLatestBeaconEntry(_ context.Context, ts *types.TipSet)
 		cur = next
 	}

-	return nil, xerrors.Errorf("found NO beacon entries in the 20 blocks prior to given tipset")
+	return nil, xerrors.Errorf("found NO beacon entries in the 20 latest tipsets")
 }

 func (syncer *Syncer) IsEpochBeyondCurrMax(epoch abi.ChainEpoch) bool {
@@ -19,13 +19,10 @@ import (

 	"github.com/filecoin-project/go-address"
 	"github.com/filecoin-project/go-state-types/abi"
-	"github.com/filecoin-project/go-state-types/big"
-	miner0 "github.com/filecoin-project/specs-actors/actors/builtin/miner"
-	power0 "github.com/filecoin-project/specs-actors/actors/builtin/power"
-	verifreg0 "github.com/filecoin-project/specs-actors/actors/builtin/verifreg"

 	"github.com/filecoin-project/lotus/api"
 	"github.com/filecoin-project/lotus/build"
+	"github.com/filecoin-project/lotus/chain/actors/policy"
 	"github.com/filecoin-project/lotus/chain/gen"
 	"github.com/filecoin-project/lotus/chain/gen/slashfilter"
 	"github.com/filecoin-project/lotus/chain/store"
@@ -43,11 +40,9 @@ func init() {
 	if err != nil {
 		panic(err)
 	}
-	miner0.SupportedProofTypes = map[abi.RegisteredSealProof]struct{}{
-		abi.RegisteredSealProof_StackedDrg2KiBV1: {},
-	}
-	power0.ConsensusMinerMinPower = big.NewInt(2048)
-	verifreg0.MinVerifiedDealSize = big.NewInt(256)
+	policy.SetSupportedProofTypes(abi.RegisteredSealProof_StackedDrg2KiBV1)
+	policy.SetConsensusMinerMinPower(abi.NewStoragePower(2048))
+	policy.SetMinVerifiedDealSize(abi.NewStoragePower(256))
 }

 const source = 0
@@ -737,7 +732,7 @@ func TestSyncInputs(t *testing.T) {

 	err := s.ValidateBlock(context.TODO(), &types.FullBlock{
 		Header: &types.BlockHeader{},
-	})
+	}, false)
 	if err == nil {
 		t.Fatal("should error on empty block")
 	}
@@ -746,7 +741,7 @@ func TestSyncInputs(t *testing.T) {

 	h.ElectionProof = nil

-	err = s.ValidateBlock(context.TODO(), &types.FullBlock{Header: h})
+	err = s.ValidateBlock(context.TODO(), &types.FullBlock{Header: h}, false)
 	if err == nil {
 		t.Fatal("should error on block with nil election proof")
 	}
@@ -4,8 +4,6 @@ import (
 	"errors"

 	"github.com/ipfs/go-cid"
-
-	builtin0 "github.com/filecoin-project/specs-actors/actors/builtin"
 )

 var ErrActorNotFound = errors.New("actor not found")
@@ -17,19 +15,3 @@ type Actor struct {
 	Nonce   uint64
 	Balance BigInt
 }
-
-func (a *Actor) IsAccountActor() bool {
-	return a.Code == builtin0.AccountActorCodeID
-}
-
-func (a *Actor) IsStorageMinerActor() bool {
-	return a.Code == builtin0.StorageMinerActorCodeID
-}
-
-func (a *Actor) IsMultisigActor() bool {
-	return a.Code == builtin0.MultisigActorCodeID
-}
-
-func (a *Actor) IsPaymentChannelActor() bool {
-	return a.Code == builtin0.PaymentChannelActorCodeID
-}
@@ -1648,7 +1648,7 @@ func (t *StateRoot) MarshalCBOR(w io.Writer) error {

 	scratch := make([]byte, 9)

-	// t.Version (uint64) (uint64)
+	// t.Version (types.StateTreeVersion) (uint64)

 	if err := cbg.WriteMajorTypeHeaderBuf(scratch, w, cbg.MajUnsignedInt, uint64(t.Version)); err != nil {
 		return err
@@ -1687,7 +1687,7 @@ func (t *StateRoot) UnmarshalCBOR(r io.Reader) error {
 		return fmt.Errorf("cbor input had wrong number of fields")
 	}

-	// t.Version (uint64) (uint64)
+	// t.Version (types.StateTreeVersion) (uint64)

 	{

@@ -1698,7 +1698,7 @@ func (t *StateRoot) UnmarshalCBOR(r io.Reader) error {
 		if maj != cbg.MajUnsignedInt {
 			return fmt.Errorf("wrong type for uint64 field")
 		}
-		t.Version = uint64(extra)
+		t.Version = StateTreeVersion(extra)

 	}
 	// t.Actors (cid.Cid) (struct)
@@ -1728,22 +1728,22 @@ func (t *StateRoot) UnmarshalCBOR(r io.Reader) error {
 	return nil
 }

-var lengthBufStateInfo = []byte{128}
+var lengthBufStateInfo0 = []byte{128}

-func (t *StateInfo) MarshalCBOR(w io.Writer) error {
+func (t *StateInfo0) MarshalCBOR(w io.Writer) error {
 	if t == nil {
 		_, err := w.Write(cbg.CborNull)
 		return err
 	}
-	if _, err := w.Write(lengthBufStateInfo); err != nil {
+	if _, err := w.Write(lengthBufStateInfo0); err != nil {
 		return err
 	}

 	return nil
 }

-func (t *StateInfo) UnmarshalCBOR(r io.Reader) error {
-	*t = StateInfo{}
+func (t *StateInfo0) UnmarshalCBOR(r io.Reader) error {
+	*t = StateInfo0{}

 	br := cbg.GetPeeker(r)
 	scratch := make([]byte, 8)
@@ -2,9 +2,20 @@ package types

 import "github.com/ipfs/go-cid"

+// StateTreeVersion is the version of the state tree itself, independent of the
+// network version or the actors version.
+type StateTreeVersion uint64
+
+const (
+	// StateTreeVersion0 corresponds to actors < v2.
+	StateTreeVersion0 StateTreeVersion = iota
+	// StateTreeVersion1 corresponds to actors >= v2.
+	StateTreeVersion1
+)
+
 type StateRoot struct {
-	// State root version. Versioned along with actors (for now).
-	Version uint64
+	// State tree version.
+	Version StateTreeVersion
 	// Actors tree. The structure depends on the state root version.
 	Actors cid.Cid
 	// Info. The structure depends on the state root version.
@@ -12,4 +23,4 @@ type StateRoot struct {
 }

 // TODO: version this.
-type StateInfo struct{}
+type StateInfo0 struct{}
@@ -167,12 +167,16 @@ func (ts *TipSet) Equals(ots *TipSet) bool {
 		return false
 	}

-	if len(ts.blks) != len(ots.blks) {
+	if ts.height != ots.height {
 		return false
 	}

-	for i, b := range ts.blks {
-		if b.Cid() != ots.blks[i].Cid() {
+	if len(ts.cids) != len(ots.cids) {
+		return false
+	}
+
+	for i, cid := range ts.cids {
+		if cid != ots.cids[i] {
 			return false
 		}
 	}
@@ -1,22 +0,0 @@
-package types
-
-import (
-	"encoding/base64"
-
-	"github.com/filecoin-project/specs-actors/actors/builtin/paych"
-	cbor "github.com/ipfs/go-ipld-cbor"
-)
-
-func DecodeSignedVoucher(s string) (*paych.SignedVoucher, error) {
-	data, err := base64.RawURLEncoding.DecodeString(s)
-	if err != nil {
-		return nil, err
-	}
-
-	var sv paych.SignedVoucher
-	if err := cbor.DecodeInto(data, &sv); err != nil {
-		return nil, err
-	}
-
-	return &sv, nil
-}
@@ -1,9 +1,12 @@
 package chain

 import (
+	"crypto/rand"
 	"encoding/json"
 	"testing"

+	"github.com/filecoin-project/lotus/build"
+
 	"github.com/filecoin-project/go-address"
 	"github.com/filecoin-project/lotus/chain/types"
 )
@@ -35,3 +38,40 @@ func TestSignedMessageJsonRoundtrip(t *testing.T) {
 		t.Fatal(err)
 	}
 }
+
+func TestAddressType(t *testing.T) {
+	build.SetAddressNetwork(address.Testnet)
+	addr, err := makeRandomAddress()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if string(addr[0]) != address.TestnetPrefix {
+		t.Fatalf("address should start with %s", address.TestnetPrefix)
+	}
+
+	build.SetAddressNetwork(address.Mainnet)
+	addr, err = makeRandomAddress()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if string(addr[0]) != address.MainnetPrefix {
+		t.Fatalf("address should start with %s", address.MainnetPrefix)
+	}
+}
+
+func makeRandomAddress() (string, error) {
+	bytes := make([]byte, 32)
+	_, err := rand.Read(bytes)
+	if err != nil {
+		return "", err
+	}
+
+	addr, err := address.NewActorAddress(bytes)
+	if err != nil {
+		return "", err
+	}
+
+	return addr.String(), nil
+}
@@ -6,28 +6,25 @@ import (
 	"math/rand"
 	"os"

-	power0 "github.com/filecoin-project/specs-actors/actors/builtin/power"
-
 	"github.com/filecoin-project/go-address"
 	"golang.org/x/xerrors"

 	"github.com/filecoin-project/go-state-types/abi"
-	"github.com/filecoin-project/go-state-types/big"
 	"github.com/filecoin-project/go-state-types/crypto"
+	"github.com/filecoin-project/lotus/chain/actors/policy"
 	"github.com/filecoin-project/lotus/chain/gen"
 	"github.com/filecoin-project/lotus/chain/types"
 	"github.com/filecoin-project/lotus/chain/types/mock"
 	"github.com/filecoin-project/lotus/chain/vectors"
 	"github.com/filecoin-project/lotus/chain/wallet"
-	verifreg0 "github.com/filecoin-project/specs-actors/actors/builtin/verifreg"

 	_ "github.com/filecoin-project/lotus/lib/sigs/bls"
 	_ "github.com/filecoin-project/lotus/lib/sigs/secp"
 )

 func init() {
-	verifreg0.MinVerifiedDealSize = big.NewInt(2048)
-	power0.ConsensusMinerMinPower = big.NewInt(2048)
+	policy.SetMinVerifiedDealSize(abi.NewStoragePower(2048))
+	policy.SetConsensusMinerMinPower(abi.NewStoragePower(2048))
 }

 func MakeHeaderVectors() []vectors.HeaderVector {
@@ -9,7 +9,6 @@ import (
 	addr "github.com/filecoin-project/go-address"
 	"github.com/filecoin-project/go-state-types/abi"
 	"github.com/filecoin-project/go-state-types/crypto"
-	"github.com/filecoin-project/specs-actors/actors/runtime"
 	vmr "github.com/filecoin-project/specs-actors/actors/runtime"
 	"github.com/ipfs/go-cid"
 )
@@ -210,7 +209,7 @@ func (ps pricedSyscalls) VerifyPoSt(vi proof.WindowPoStVerifyInfo) error {
 // the "parent grinding fault", in which case it must be the sibling of h1 (same parent tipset) and one of the
 // blocks in the parent of h2 (i.e. h2's grandparent).
 // Returns nil and an error if the headers don't prove a fault.
-func (ps pricedSyscalls) VerifyConsensusFault(h1 []byte, h2 []byte, extra []byte) (*runtime.ConsensusFault, error) {
+func (ps pricedSyscalls) VerifyConsensusFault(h1 []byte, h2 []byte, extra []byte) (*vmr.ConsensusFault, error) {
 	ps.chargeGas(ps.pl.OnVerifyConsensusFault())
 	defer ps.chargeGas(gasOnActorExec)

@@ -8,7 +8,7 @@ import (
 	"github.com/filecoin-project/go-state-types/abi"
 	"github.com/filecoin-project/go-state-types/big"
 	"github.com/filecoin-project/go-state-types/crypto"
-	"github.com/filecoin-project/specs-actors/actors/builtin"
+	builtin0 "github.com/filecoin-project/specs-actors/actors/builtin"
 )

 type scalingCost struct {
@@ -112,14 +112,14 @@ func (pl *pricelistV0) OnMethodInvocation(value abi.TokenAmount, methodNum abi.M

 	if big.Cmp(value, abi.NewTokenAmount(0)) != 0 {
 		ret += pl.sendTransferFunds
-		if methodNum == builtin.MethodSend {
+		if methodNum == builtin0.MethodSend {
 			// transfer only
 			ret += pl.sendTransferOnlyPremium
 		}
 		extra += "t"
 	}

-	if methodNum != builtin.MethodSend {
+	if methodNum != builtin0.MethodSend {
 		extra += "i"
 		// running actors is cheaper becase we hand over to actors
 		ret += pl.sendInvokeMethod
@@ -6,91 +6,126 @@ import (
 	"fmt"
 	"reflect"

+	"github.com/filecoin-project/lotus/chain/actors/builtin"
+
 	"github.com/ipfs/go-cid"
 	cbg "github.com/whyrusleeping/cbor-gen"
 	"golang.org/x/xerrors"

-	builtin0 "github.com/filecoin-project/specs-actors/actors/builtin"
-	account0 "github.com/filecoin-project/specs-actors/actors/builtin/account"
-	cron0 "github.com/filecoin-project/specs-actors/actors/builtin/cron"
-	init0 "github.com/filecoin-project/specs-actors/actors/builtin/init"
-	market0 "github.com/filecoin-project/specs-actors/actors/builtin/market"
-	miner0 "github.com/filecoin-project/specs-actors/actors/builtin/miner"
-	msig0 "github.com/filecoin-project/specs-actors/actors/builtin/multisig"
-	paych0 "github.com/filecoin-project/specs-actors/actors/builtin/paych"
-	power0 "github.com/filecoin-project/specs-actors/actors/builtin/power"
-	reward0 "github.com/filecoin-project/specs-actors/actors/builtin/reward"
-	system0 "github.com/filecoin-project/specs-actors/actors/builtin/system"
-	verifreg0 "github.com/filecoin-project/specs-actors/actors/builtin/verifreg"
-	vmr "github.com/filecoin-project/specs-actors/actors/runtime"
+	exported0 "github.com/filecoin-project/specs-actors/actors/builtin/exported"
+	exported2 "github.com/filecoin-project/specs-actors/v2/actors/builtin/exported"
+	vmr "github.com/filecoin-project/specs-actors/v2/actors/runtime"

 	"github.com/filecoin-project/go-state-types/abi"
 	"github.com/filecoin-project/go-state-types/exitcode"
+	rtt "github.com/filecoin-project/go-state-types/rt"

+	"github.com/filecoin-project/lotus/chain/actors"
 	"github.com/filecoin-project/lotus/chain/actors/aerrors"
+	"github.com/filecoin-project/lotus/chain/types"
 )

-type Invoker struct {
-	builtInCode  map[cid.Cid]nativeCode
-	builtInState map[cid.Cid]reflect.Type
+type ActorRegistry struct {
+	actors map[cid.Cid]*actorInfo
+}
+
+// An ActorPredicate returns an error if the given actor is not valid for the given runtime environment (e.g., chain height, version, etc.).
+type ActorPredicate func(vmr.Runtime, rtt.VMActor) error
+
+func ActorsVersionPredicate(ver actors.Version) ActorPredicate {
+	return func(rt vmr.Runtime, v rtt.VMActor) error {
+		nver := actors.VersionForNetwork(rt.NetworkVersion())
+		if nver != ver {
+			return xerrors.Errorf("actor %s is a version %d actor; chain only supports actor version %d at height %d", v.Code(), ver, nver, rt.CurrEpoch())
+		}
+		return nil
+	}
 }

 type invokeFunc func(rt vmr.Runtime, params []byte) ([]byte, aerrors.ActorError)
 type nativeCode []invokeFunc

-func NewInvoker() *Invoker {
-	inv := &Invoker{
-		builtInCode:  make(map[cid.Cid]nativeCode),
-		builtInState: make(map[cid.Cid]reflect.Type),
-	}
+type actorInfo struct {
+	methods nativeCode
+	vmActor rtt.VMActor
+	// TODO: consider making this a network version range?
+	predicate ActorPredicate
+}
+
+func NewActorRegistry() *ActorRegistry {
+	inv := &ActorRegistry{actors: make(map[cid.Cid]*actorInfo)}
+
+	// TODO: define all these properties on the actors themselves, in specs-actors.

 	// add builtInCode using: register(cid, singleton)
-	// NETUPGRADE: register code IDs for v2, etc.
-	inv.Register(builtin0.SystemActorCodeID, system0.Actor{}, abi.EmptyValue{})
-	inv.Register(builtin0.InitActorCodeID, init0.Actor{}, init0.State{})
-	inv.Register(builtin0.RewardActorCodeID, reward0.Actor{}, reward0.State{})
-	inv.Register(builtin0.CronActorCodeID, cron0.Actor{}, cron0.State{})
-	inv.Register(builtin0.StoragePowerActorCodeID, power0.Actor{}, power0.State{})
-	inv.Register(builtin0.StorageMarketActorCodeID, market0.Actor{}, market0.State{})
-	inv.Register(builtin0.StorageMinerActorCodeID, miner0.Actor{}, miner0.State{})
-	inv.Register(builtin0.MultisigActorCodeID, msig0.Actor{}, msig0.State{})
-	inv.Register(builtin0.PaymentChannelActorCodeID, paych0.Actor{}, paych0.State{})
-	inv.Register(builtin0.VerifiedRegistryActorCodeID, verifreg0.Actor{}, verifreg0.State{})
-	inv.Register(builtin0.AccountActorCodeID, account0.Actor{}, account0.State{})
+	inv.Register(ActorsVersionPredicate(actors.Version0), exported0.BuiltinActors()...)
+	inv.Register(ActorsVersionPredicate(actors.Version2), exported2.BuiltinActors()...)

 	return inv
 }

-func (inv *Invoker) Invoke(codeCid cid.Cid, rt vmr.Runtime, method abi.MethodNum, params []byte) ([]byte, aerrors.ActorError) {
-
-	code, ok := inv.builtInCode[codeCid]
+func (ar *ActorRegistry) Invoke(codeCid cid.Cid, rt vmr.Runtime, method abi.MethodNum, params []byte) ([]byte, aerrors.ActorError) {
+	act, ok := ar.actors[codeCid]
 	if !ok {
 		log.Errorf("no code for actor %s (Addr: %s)", codeCid, rt.Receiver())
 		return nil, aerrors.Newf(exitcode.SysErrorIllegalActor, "no code for actor %s(%d)(%s)", codeCid, method, hex.EncodeToString(params))
 	}
-	if method >= abi.MethodNum(len(code)) || code[method] == nil {
+	if err := act.predicate(rt, act.vmActor); err != nil {
+		return nil, aerrors.Newf(exitcode.SysErrorIllegalActor, "unsupported actor: %s", err)
+	}
+	if method >= abi.MethodNum(len(act.methods)) || act.methods[method] == nil {
 		return nil, aerrors.Newf(exitcode.SysErrInvalidMethod, "no method %d on actor", method)
 	}
-	return code[method](rt, params)
+	return act.methods[method](rt, params)

 }

-func (inv *Invoker) Register(c cid.Cid, instance Invokee, state interface{}) {
-	code, err := inv.transform(instance)
-	if err != nil {
-		panic(xerrors.Errorf("%s: %w", string(c.Hash()), err))
+func (ar *ActorRegistry) Register(pred ActorPredicate, actors ...rtt.VMActor) {
+	if pred == nil {
+		pred = func(vmr.Runtime, rtt.VMActor) error { return nil }
+	}
+	for _, a := range actors {
+		code, err := ar.transform(a)
+		if err != nil {
+			panic(xerrors.Errorf("%s: %w", string(a.Code().Hash()), err))
+		}
+		ar.actors[a.Code()] = &actorInfo{
+			methods:   code,
+			vmActor:   a,
+			predicate: pred,
+		}
 	}
-	inv.builtInCode[c] = code
-	inv.builtInState[c] = reflect.TypeOf(state)
 }

-type Invokee interface {
+func (ar *ActorRegistry) Create(codeCid cid.Cid, rt vmr.Runtime) (*types.Actor, aerrors.ActorError) {
+	act, ok := ar.actors[codeCid]
+	if !ok {
+		return nil, aerrors.Newf(exitcode.SysErrorIllegalArgument, "Can only create built-in actors.")
+	}
+
+	if err := act.predicate(rt, act.vmActor); err != nil {
+		return nil, aerrors.Newf(exitcode.SysErrorIllegalArgument, "Cannot create actor: %w", err)
+	}
+
+	if rtt.IsSingletonActor(act.vmActor) {
+		return nil, aerrors.Newf(exitcode.SysErrorIllegalArgument, "Can only have one instance of singleton actors.")
+	}
+	return &types.Actor{
+		Code:    codeCid,
+		Head:    EmptyObjectCid,
+		Nonce:   0,
+		Balance: abi.NewTokenAmount(0),
+	}, nil
+}
+
+type invokee interface {
 	Exports() []interface{}
 }

-func (*Invoker) transform(instance Invokee) (nativeCode, error) {
+func (*ActorRegistry) transform(instance invokee) (nativeCode, error) {
 	itype := reflect.TypeOf(instance)
 	exports := instance.Exports()
+	runtimeType := reflect.TypeOf((*vmr.Runtime)(nil)).Elem()
 	for i, m := range exports {
 		i := i
 		newErr := func(format string, args ...interface{}) error {
@@ -111,7 +146,7 @@ func (*Invoker) transform(instance Invokee) (nativeCode, error) {
 			return nil, newErr("wrong number of inputs should be: " +
 				"vmr.Runtime, <parameter>")
 		}
-		if t.In(0) != reflect.TypeOf((*vmr.Runtime)(nil)).Elem() {
+		if !runtimeType.Implements(t.In(0)) {
 			return nil, newErr("first arguemnt should be vmr.Runtime")
 		}
 		if t.In(1).Kind() != reflect.Ptr {
@@ -176,27 +211,22 @@ func DecodeParams(b []byte, out interface{}) error {
 	return um.UnmarshalCBOR(bytes.NewReader(b))
 }

-func DumpActorState(code cid.Cid, b []byte) (interface{}, error) {
-	if code == builtin0.AccountActorCodeID { // Account code special case
+func DumpActorState(act *types.Actor, b []byte) (interface{}, error) {
+	if builtin.IsAccountActor(act.Code) { // Account code special case
 		return nil, nil
 	}

-	i := NewInvoker() // TODO: register builtins in init block
+	i := NewActorRegistry() // TODO: register builtins in init block

-	typ, ok := i.builtInState[code]
+	actInfo, ok := i.actors[act.Code]
 	if !ok {
-		return nil, xerrors.Errorf("state type for actor %s not found", code)
-	}
-
-	rv := reflect.New(typ)
-	um, ok := rv.Interface().(cbg.CBORUnmarshaler)
-	if !ok {
-		return nil, xerrors.New("state type does not implement CBORUnmarshaler")
+		return nil, xerrors.Errorf("state type for actor %s not found", act.Code)
 	}

+	um := actInfo.vmActor.State()
 	if err := um.UnmarshalCBOR(bytes.NewReader(b)); err != nil {
 		return nil, xerrors.Errorf("unmarshaling actor state: %w", err)
 	}

-	return rv.Elem().Interface(), nil
+	return um, nil
 }
@@ -77,7 +77,7 @@ func (basicContract) InvokeSomething10(rt runtime.Runtime, params *basicParams)
 }

 func TestInvokerBasic(t *testing.T) {
-	inv := Invoker{}
+	inv := ActorRegistry{}
 	code, err := inv.transform(basicContract{})
 	assert.NoError(t, err)

@@ -6,11 +6,13 @@ import (
 	"github.com/filecoin-project/go-state-types/big"
 	"github.com/filecoin-project/go-state-types/exitcode"
 	"github.com/filecoin-project/lotus/chain/actors"
-	"github.com/filecoin-project/specs-actors/actors/builtin"

 	"github.com/ipfs/go-cid"
 	cbor "github.com/ipfs/go-ipld-cbor"

+	builtin0 "github.com/filecoin-project/specs-actors/actors/builtin"
+	builtin2 "github.com/filecoin-project/specs-actors/v2/actors/builtin"
+
 	"github.com/filecoin-project/go-address"
 	"github.com/filecoin-project/lotus/chain/actors/aerrors"
 	"github.com/filecoin-project/lotus/chain/types"
@@ -29,49 +31,47 @@ func init() {
 var EmptyObjectCid cid.Cid

 // TryCreateAccountActor creates account actors from only BLS/SECP256K1 addresses.
-func TryCreateAccountActor(rt *Runtime, addr address.Address) (*types.Actor, aerrors.ActorError) {
+func TryCreateAccountActor(rt *Runtime, addr address.Address) (*types.Actor, address.Address, aerrors.ActorError) {
 	if err := rt.chargeGasSafe(PricelistByEpoch(rt.height).OnCreateActor()); err != nil {
-		return nil, err
+		return nil, address.Undef, err
 	}

 	addrID, err := rt.state.RegisterNewAddress(addr)
 	if err != nil {
-		return nil, aerrors.Escalate(err, "registering actor address")
+		return nil, address.Undef, aerrors.Escalate(err, "registering actor address")
 	}

-	act, aerr := makeActor(addr)
+	act, aerr := makeActor(actors.VersionForNetwork(rt.NetworkVersion()), addr)
 	if aerr != nil {
-		return nil, aerr
+		return nil, address.Undef, aerr
 	}

 	if err := rt.state.SetActor(addrID, act); err != nil {
-		return nil, aerrors.Escalate(err, "creating new actor failed")
+		return nil, address.Undef, aerrors.Escalate(err, "creating new actor failed")
 	}

 	p, err := actors.SerializeParams(&addr)
 	if err != nil {
-		return nil, aerrors.Escalate(err, "couldn't serialize params for actor construction")
+		return nil, address.Undef, aerrors.Escalate(err, "couldn't serialize params for actor construction")
 	}
 	// call constructor on account

-	_, aerr = rt.internalSend(builtin.SystemActorAddr, addrID, builtin.MethodsAccount.Constructor, big.Zero(), p)
+	_, aerr = rt.internalSend(builtin0.SystemActorAddr, addrID, builtin0.MethodsAccount.Constructor, big.Zero(), p)
 	if aerr != nil {
-		return nil, aerrors.Wrap(aerr, "failed to invoke account constructor")
+		return nil, address.Undef, aerrors.Wrap(aerr, "failed to invoke account constructor")
 	}

 	act, err = rt.state.GetActor(addrID)
 	if err != nil {
-		return nil, aerrors.Escalate(err, "loading newly created actor failed")
+		return nil, address.Undef, aerrors.Escalate(err, "loading newly created actor failed")
 	}
-	return act, nil
+	return act, addrID, nil
 }

-func makeActor(addr address.Address) (*types.Actor, aerrors.ActorError) {
+func makeActor(ver actors.Version, addr address.Address) (*types.Actor, aerrors.ActorError) {
 	switch addr.Protocol() {
-	case address.BLS:
-		return NewBLSAccountActor(), nil
-	case address.SECP256K1:
-		return NewSecp256k1AccountActor(), nil
+	case address.BLS, address.SECP256K1:
+		return newAccountActor(ver), nil
 	case address.ID:
 		return nil, aerrors.Newf(exitcode.SysErrInvalidReceiver, "no actor with given ID: %s", addr)
 	case address.Actor:
@@ -81,19 +81,19 @@ func makeActor(addr address.Address) (*types.Actor, aerrors.ActorError) {
 	}
 }

-func NewBLSAccountActor() *types.Actor {
+func newAccountActor(ver actors.Version) *types.Actor {
+	// TODO: ActorsUpgrade use a global actor registry?
+	var code cid.Cid
+	switch ver {
+	case actors.Version0:
+		code = builtin0.AccountActorCodeID
+	case actors.Version2:
+		code = builtin2.AccountActorCodeID
+	default:
+		panic("unsupported actors version")
+	}
 	nact := &types.Actor{
-		Code:    builtin.AccountActorCodeID,
-		Balance: types.NewInt(0),
-		Head:    EmptyObjectCid,
-	}
-
-	return nact
-}
-
-func NewSecp256k1AccountActor() *types.Actor {
-	nact := &types.Actor{
-		Code:    builtin.AccountActorCodeID,
+		Code:    code,
 		Balance: types.NewInt(0),
 		Head:    EmptyObjectCid,
 	}
@@ -5,19 +5,17 @@ import (
 	"context"
 	"encoding/binary"
 	"fmt"
-	gruntime "runtime"
 	"time"

 	"github.com/filecoin-project/go-address"
 	"github.com/filecoin-project/go-state-types/abi"
-	"github.com/filecoin-project/go-state-types/big"
 	"github.com/filecoin-project/go-state-types/cbor"
 	"github.com/filecoin-project/go-state-types/crypto"
 	"github.com/filecoin-project/go-state-types/exitcode"
 	"github.com/filecoin-project/go-state-types/network"
 	rtt "github.com/filecoin-project/go-state-types/rt"
-	"github.com/filecoin-project/specs-actors/actors/builtin"
 	rt0 "github.com/filecoin-project/specs-actors/actors/runtime"
+	rt2 "github.com/filecoin-project/specs-actors/v2/actors/runtime"
 	"github.com/ipfs/go-cid"
 	ipldcbor "github.com/ipfs/go-ipld-cbor"
 	"go.opencensus.io/trace"
@@ -29,8 +27,33 @@ import (
 	"github.com/filecoin-project/lotus/chain/types"
 )

+type Message struct {
+	msg types.Message
+}
+
+func (m *Message) Caller() address.Address {
+	if m.msg.From.Protocol() != address.ID {
+		panic("runtime message has a non-ID caller")
+	}
+	return m.msg.From
+}
+
+func (m *Message) Receiver() address.Address {
+	if m.msg.To != address.Undef && m.msg.To.Protocol() != address.ID {
+		panic("runtime message has a non-ID receiver")
+	}
+	return m.msg.To
+}
+
+func (m *Message) ValueReceived() abi.TokenAmount {
+	return m.msg.Value
+}
+
+// EnableGasTracing, if true, outputs gas tracing in execution traces.
+var EnableGasTracing = false
+
 type Runtime struct {
-	types.Message
+	rt0.Message
 	rt0.Syscalls

 	ctx context.Context
@@ -111,6 +134,7 @@ func (rt *Runtime) StorePut(x cbor.Marshaler) cid.Cid {
 }

 var _ rt0.Runtime = (*Runtime)(nil)
+var _ rt2.Runtime = (*Runtime)(nil)

 func (rt *Runtime) shimCall(f func() interface{}) (rval []byte, aerr aerrors.ActorError) {
 	defer func() {
@@ -123,7 +147,11 @@ func (rt *Runtime) shimCall(f func() interface{}) (rval []byte, aerr aerrors.Act
 			//log.Desugar().WithOptions(zap.AddStacktrace(zapcore.ErrorLevel)).
 			//Sugar().Errorf("spec actors failure: %s", r)
 			log.Errorf("spec actors failure: %s", r)
-			aerr = aerrors.Newf(1, "spec actors failure: %s", r)
+			if rt.NetworkVersion() <= network.Version3 {
+				aerr = aerrors.Newf(1, "spec actors failure: %s", r)
+			} else {
+				aerr = aerrors.Newf(exitcode.SysErrReserved1, "spec actors failure: %s", r)
+			}
 		}
 	}()

@@ -216,12 +244,9 @@ func (rt *Runtime) NewActorAddress() address.Address {
 }

 func (rt *Runtime) CreateActor(codeID cid.Cid, address address.Address) {
-	if !builtin.IsBuiltinActor(codeID) {
-		rt.Abortf(exitcode.SysErrorIllegalArgument, "Can only create built-in actors.")
-	}
-
-	if builtin.IsSingletonActor(codeID) {
-		rt.Abortf(exitcode.SysErrorIllegalArgument, "Can only have one instance of singleton actors.")
+	act, aerr := rt.vm.areg.Create(codeID, rt)
+	if aerr != nil {
+		rt.Abortf(aerr.RetCode(), aerr.Error())
 	}

 	_, err := rt.state.GetActor(address)
@@ -231,12 +256,7 @@ func (rt *Runtime) CreateActor(codeID cid.Cid, address address.Address) {

 	rt.chargeGas(rt.Pricelist().OnCreateActor())

-	err = rt.state.SetActor(address, &types.Actor{
-		Code:    codeID,
-		Head:    EmptyObjectCid,
-		Nonce:   0,
-		Balance: big.Zero(),
-	})
+	err = rt.state.SetActor(address, act)
 	if err != nil {
 		panic(aerrors.Fatalf("creating actor entry: %v", err))
 	}
@@ -460,8 +480,10 @@ func (rt *Runtime) stateCommit(oldh, newh cid.Cid) aerrors.ActorError {
 }

 func (rt *Runtime) finilizeGasTracing() {
-	if rt.lastGasCharge != nil {
-		rt.lastGasCharge.TimeTaken = time.Since(rt.lastGasChargeTime)
+	if EnableGasTracing {
+		if rt.lastGasCharge != nil {
+			rt.lastGasCharge.TimeTaken = time.Since(rt.lastGasChargeTime)
+		}
 	}
 }

@@ -492,32 +514,35 @@ func (rt *Runtime) chargeGasFunc(skip int) func(GasCharge) {

 func (rt *Runtime) chargeGasInternal(gas GasCharge, skip int) aerrors.ActorError {
 	toUse := gas.Total()
-	var callers [10]uintptr
-	cout := gruntime.Callers(2+skip, callers[:])
+	if EnableGasTracing {
+		var callers [10]uintptr

-	now := build.Clock.Now()
-	if rt.lastGasCharge != nil {
-		rt.lastGasCharge.TimeTaken = now.Sub(rt.lastGasChargeTime)
+		cout := 0 //gruntime.Callers(2+skip, callers[:])
+
+		now := build.Clock.Now()
+		if rt.lastGasCharge != nil {
+			rt.lastGasCharge.TimeTaken = now.Sub(rt.lastGasChargeTime)
+		}
+
+		gasTrace := types.GasTrace{
+			Name:  gas.Name,
+			Extra: gas.Extra,
+
+			TotalGas:   toUse,
+			ComputeGas: gas.ComputeGas,
+			StorageGas: gas.StorageGas,
+
+			TotalVirtualGas:   gas.VirtualCompute*GasComputeMulti + gas.VirtualStorage*GasStorageMulti,
+			VirtualComputeGas: gas.VirtualCompute,
+			VirtualStorageGas: gas.VirtualStorage,
+
+			Callers: callers[:cout],
+		}
+		rt.executionTrace.GasCharges = append(rt.executionTrace.GasCharges, &gasTrace)
+		rt.lastGasChargeTime = now
+		rt.lastGasCharge = &gasTrace
 	}

-	gasTrace := types.GasTrace{
-		Name:  gas.Name,
-		Extra: gas.Extra,
-
-		TotalGas:   toUse,
-		ComputeGas: gas.ComputeGas,
-		StorageGas: gas.StorageGas,
-
-		TotalVirtualGas:   gas.VirtualCompute*GasComputeMulti + gas.VirtualStorage*GasStorageMulti,
-		VirtualComputeGas: gas.VirtualCompute,
-		VirtualStorageGas: gas.VirtualStorage,
-
-		Callers: callers[:cout],
-	}
-	rt.executionTrace.GasCharges = append(rt.executionTrace.GasCharges, &gasTrace)
-	rt.lastGasChargeTime = now
-	rt.lastGasCharge = &gasTrace
-
 	// overflow safe
 	if rt.gasUsed > rt.gasAvailable-toUse {
 		rt.gasUsed = rt.gasAvailable
@@ -45,3 +45,23 @@ func TestRuntimePutErrors(t *testing.T) {
 	rt.StorePut(&NotAVeryGoodMarshaler{})
 	t.Error("expected panic")
 }
+
+func BenchmarkRuntime_CreateRuntimeChargeGas_TracingDisabled(b *testing.B) {
+	var (
+		cst = cbor.NewCborStore(nil)
+		gch = newGasCharge("foo", 1000, 1000)
+	)
+
+	b.ResetTimer()
+
+	EnableGasTracing = false
+	noop := func() bool { return EnableGasTracing }
+	for n := 0; n < b.N; n++ {
+		// flip the value and access it to make sure
+		// the compiler doesn't optimize away
+		EnableGasTracing = true
+		_ = noop()
+		EnableGasTracing = false
+		_ = (&Runtime{cst: cst}).chargeGasInternal(gch, 0)
+	}
+}
@@ -5,8 +5,11 @@ import (
 	"context"
 	"fmt"
 	"reflect"
+	"sync/atomic"
 	"time"

+	"github.com/filecoin-project/lotus/chain/actors/builtin"
+
 	block "github.com/ipfs/go-block-format"
 	cid "github.com/ipfs/go-cid"
 	cbor "github.com/ipfs/go-ipld-cbor"
@@ -22,7 +25,6 @@ import (
 	"github.com/filecoin-project/go-state-types/crypto"
 	"github.com/filecoin-project/go-state-types/exitcode"
 	"github.com/filecoin-project/go-state-types/network"
-	"github.com/filecoin-project/specs-actors/actors/builtin"

 	"github.com/filecoin-project/lotus/build"
 	"github.com/filecoin-project/lotus/chain/actors/adt"
@@ -40,6 +42,12 @@ var log = logging.Logger("vm")
 var actorLog = logging.Logger("actors")
 var gasOnActorExec = newGasCharge("OnActorExec", 0, 0)

+// stat counters
+var (
+	StatSends   uint64
+	StatApplied uint64
+)
+
 // ResolveToKeyAddr returns the public key type of address (`BLS`/`SECP256K1`) of an account actor identified by `addr`.
 func ResolveToKeyAddr(state types.StateTree, cst cbor.IpldStore, addr address.Address) (address.Address, error) {
 	if addr.Protocol() == address.BLS || addr.Protocol() == address.SECP256K1 {
@@ -123,7 +131,15 @@ func (vm *VM) makeRuntime(ctx context.Context, msg *types.Message, origin addres
 		rt.Abortf(exitcode.SysErrInvalidReceiver, "resolve msg.From address failed")
 	}
 	vmm.From = resF
-	rt.Message = vmm
+
+	if vm.ntwkVersion(ctx, vm.blockHeight) <= network.Version3 {
+		rt.Message = &vmm
+	} else {
+		resT, _ := rt.ResolveAddress(msg.To)
+		// may be set to undef if recipient doesn't exist yet
+		vmm.To = resT
+		rt.Message = &Message{msg: vmm}
+	}

 	return rt
 }
@@ -145,7 +161,7 @@ type VM struct {
 	cst            *cbor.BasicIpldStore
 	buf            *bufbstore.BufferedBS
 	blockHeight    abi.ChainEpoch
-	inv            *Invoker
+	areg           *ActorRegistry
 	rand           Rand
 	circSupplyCalc CircSupplyCalculator
 	ntwkVersion    NtwkVersionGetter
@@ -179,7 +195,7 @@ func NewVM(ctx context.Context, opts *VMOpts) (*VM, error) {
 		cst:            cst,
 		buf:            buf,
 		blockHeight:    opts.Epoch,
-		inv:            NewInvoker(),
+		areg:           NewActorRegistry(),
 		rand:           opts.Rand, // TODO: Probably should be a syscall
 		circSupplyCalc: opts.CircSupplyCalc,
 		ntwkVersion:    opts.NtwkVersion,
@@ -204,6 +220,8 @@ type ApplyRet struct {
 func (vm *VM) send(ctx context.Context, msg *types.Message, parent *Runtime,
 	gasCharge *GasCharge, start time.Time) ([]byte, aerrors.ActorError, *Runtime) {

+	defer atomic.AddUint64(&StatSends, 1)
+
 	st := vm.cstate

 	origin := msg.From
@@ -218,14 +236,21 @@ func (vm *VM) send(ctx context.Context, msg *types.Message, parent *Runtime,
 	}

 	rt := vm.makeRuntime(ctx, msg, origin, on, gasUsed, nac)
-	rt.lastGasChargeTime = start
+	if EnableGasTracing {
+		rt.lastGasChargeTime = start
+		if parent != nil {
+			rt.lastGasChargeTime = parent.lastGasChargeTime
+			rt.lastGasCharge = parent.lastGasCharge
+			defer func() {
+				parent.lastGasChargeTime = rt.lastGasChargeTime
+				parent.lastGasCharge = rt.lastGasCharge
+			}()
+		}
+	}
+
 	if parent != nil {
-		rt.lastGasChargeTime = parent.lastGasChargeTime
-		rt.lastGasCharge = parent.lastGasCharge
 		defer func() {
 			parent.gasUsed = rt.gasUsed
-			parent.lastGasChargeTime = rt.lastGasChargeTime
-			parent.lastGasCharge = rt.lastGasCharge
 		}()
 	}
 	if gasCharge != nil {
@@ -240,11 +265,24 @@ func (vm *VM) send(ctx context.Context, msg *types.Message, parent *Runtime,
 		toActor, err := st.GetActor(msg.To)
 		if err != nil {
 			if xerrors.Is(err, types.ErrActorNotFound) {
-				a, err := TryCreateAccountActor(rt, msg.To)
+				a, aid, err := TryCreateAccountActor(rt, msg.To)
 				if err != nil {
 					return nil, aerrors.Wrapf(err, "could not create account")
 				}
 				toActor = a
+				if vm.ntwkVersion(ctx, vm.blockHeight) <= network.Version3 {
+					// Leave the rt.Message as is
+				} else {
+					nmsg := Message{
+						msg: types.Message{
+							To:    aid,
+							From:  rt.Message.Caller(),
+							Value: rt.Message.ValueReceived(),
+						},
+					}
+
+					rt.Message = &nmsg
+				}
 			} else {
 				return nil, aerrors.Escalate(err, "getting actor")
 			}
@@ -312,6 +350,7 @@ func checkMessage(msg *types.Message) error {

 func (vm *VM) ApplyImplicitMessage(ctx context.Context, msg *types.Message) (*ApplyRet, error) {
 	start := build.Clock.Now()
+	defer atomic.AddUint64(&StatApplied, 1)
 	ret, actorErr, rt := vm.send(ctx, msg, nil, nil, start)
 	rt.finilizeGasTracing()
 	return &ApplyRet{
@@ -331,6 +370,7 @@ func (vm *VM) ApplyMessage(ctx context.Context, cmsg types.ChainMsg) (*ApplyRet,
 	start := build.Clock.Now()
 	ctx, span := trace.StartSpan(ctx, "vm.ApplyMessage")
 	defer span.End()
+	defer atomic.AddUint64(&StatApplied, 1)
 	msg := cmsg.VMMessage()
 	if span.IsRecordingEvents() {
 		span.AddAttributes(
@@ -385,7 +425,7 @@ func (vm *VM) ApplyMessage(ctx context.Context, cmsg types.ChainMsg) (*ApplyRet,
 	}

 	// this should never happen, but is currently still exercised by some tests
-	if !fromActor.IsAccountActor() {
+	if !builtin.IsAccountActor(fromActor.Code) {
 		gasOutputs := ZeroGasOutputs()
 		gasOutputs.MinerPenalty = minerPenaltyAmount
 		return &ApplyRet{
@@ -546,7 +586,7 @@ func (vm *VM) Flush(ctx context.Context) (cid.Cid, error) {
 		return cid.Undef, xerrors.Errorf("flushing vm: %w", err)
 	}

-	if err := Copy(from, to, root); err != nil {
+	if err := Copy(ctx, from, to, root); err != nil {
 		return cid.Undef, xerrors.Errorf("copying tree: %w", err)
 	}

@@ -600,9 +640,18 @@ func linksForObj(blk block.Block, cb func(cid.Cid)) error {
 	}
 }

-func Copy(from, to blockstore.Blockstore, root cid.Cid) error {
+func Copy(ctx context.Context, from, to blockstore.Blockstore, root cid.Cid) error {
+	ctx, span := trace.StartSpan(ctx, "vm.Copy") // nolint
+	defer span.End()
+
+	var numBlocks int
+	var totalCopySize int
+
 	var batch []block.Block
 	batchCp := func(blk block.Block) error {
+		numBlocks++
+		totalCopySize += len(blk.RawData())
+
 		batch = append(batch, blk)
 		if len(batch) > 100 {
 			if err := to.PutMany(batch); err != nil {
@@ -623,6 +672,11 @@ func Copy(from, to blockstore.Blockstore, root cid.Cid) error {
 		}
 	}

+	span.AddAttributes(
+		trace.Int64Attribute("numBlocks", int64(numBlocks)),
+		trace.Int64Attribute("copySize", int64(totalCopySize)),
+	)
+
 	return nil
 }

@@ -709,15 +763,15 @@ func (vm *VM) Invoke(act *types.Actor, rt *Runtime, method abi.MethodNum, params
 	defer func() {
 		rt.ctx = oldCtx
 	}()
-	ret, err := vm.inv.Invoke(act.Code, rt, method, params)
+	ret, err := vm.areg.Invoke(act.Code, rt, method, params)
 	if err != nil {
 		return nil, err
 	}
 	return ret, nil
 }

-func (vm *VM) SetInvoker(i *Invoker) {
-	vm.inv = i
+func (vm *VM) SetInvoker(i *ActorRegistry) {
+	vm.areg = i
 }

 func (vm *VM) GetNtwkVersion(ctx context.Context, ce abi.ChainEpoch) network.Version {
@@ -81,7 +81,7 @@ func (w *Wallet) findKey(addr address.Address) (*Key, error) {
 		return nil, nil
 	}

-	ki, err := w.keystore.Get(KNamePrefix + addr.String())
+	ki, err := w.tryFind(addr)
 	if err != nil {
 		if xerrors.Is(err, types.ErrKeyInfoNotFound) {
 			return nil, nil
@@ -96,6 +96,42 @@ func (w *Wallet) findKey(addr address.Address) (*Key, error) {
 	return k, nil
 }

+func (w *Wallet) tryFind(addr address.Address) (types.KeyInfo, error) {
+
+	ki, err := w.keystore.Get(KNamePrefix + addr.String())
+	if err == nil {
+		return ki, err
+	}
+
+	if !xerrors.Is(err, types.ErrKeyInfoNotFound) {
+		return types.KeyInfo{}, err
+	}
+
+	// We got an ErrKeyInfoNotFound error
+	// Try again, this time with the testnet prefix
+
+	aChars := []rune(addr.String())
+	prefixRunes := []rune(address.TestnetPrefix)
+	if len(prefixRunes) != 1 {
+		return types.KeyInfo{}, xerrors.Errorf("unexpected prefix length: %d", len(prefixRunes))
+	}
+
+	aChars[0] = prefixRunes[0]
+	ki, err = w.keystore.Get(KNamePrefix + string(aChars))
+	if err != nil {
+		return types.KeyInfo{}, err
+	}
+
+	// We found it with the testnet prefix
+	// Add this KeyInfo with the mainnet prefix address string
+	err = w.keystore.Put(KNamePrefix+addr.String(), ki)
+	if err != nil {
+		return types.KeyInfo{}, err
+	}
+
+	return ki, nil
+}
+
 func (w *Wallet) Export(addr address.Address) (*types.KeyInfo, error) {
 	k, err := w.findKey(addr)
 	if err != nil {
@@ -129,6 +165,7 @@ func (w *Wallet) ListAddrs() ([]address.Address, error) {

 	sort.Strings(all)

+	seen := map[address.Address]struct{}{}
 	out := make([]address.Address, 0, len(all))
 	for _, a := range all {
 		if strings.HasPrefix(a, KNamePrefix) {
@@ -137,10 +174,19 @@ func (w *Wallet) ListAddrs() ([]address.Address, error) {
 			if err != nil {
 				return nil, xerrors.Errorf("converting name to address: %w", err)
 			}
+			if _, ok := seen[addr]; ok {
+				continue // got duplicate with a different prefix
+			}
+			seen[addr] = struct{}{}
+
 			out = append(out, addr)
 		}
 	}

+	sort.Slice(out, func(i, j int) bool {
+		return out[i].String() < out[j].String()
+	})
+
 	return out, nil
 }

--- a/Show More
+++ b/Show More