diff --git a/api/test/ccupgrade.go b/api/test/ccupgrade.go
index f58f1ff6e..97fb665ed 100644
--- a/api/test/ccupgrade.go
+++ b/api/test/ccupgrade.go
@@ -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]
 
diff --git a/api/test/deals.go b/api/test/deals.go
index 12cd0607a..aa5bfa716 100644
--- a/api/test/deals.go
+++ b/api/test/deals.go
@@ -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)
 		}
 	}
 
diff --git a/api/test/paych.go b/api/test/paych.go
index 15ce352bd..e95773b6a 100644
--- a/api/test/paych.go
+++ b/api/test/paych.go
@@ -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"
@@ -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 {
@@ -215,7 +228,7 @@ func TestPaymentChannels(t *testing.T, b APIBuilder, blocktime time.Duration) {
 	}
 
 	// 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 {
@@ -271,7 +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)
diff --git a/api/test/test.go b/api/test/test.go
index 409274ff1..853267eff 100644
--- a/api/test/test.go
+++ b/api/test/test.go
@@ -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
 }
diff --git a/api/test/window_post.go b/api/test/window_post.go
index 958c91816..eadcdbb05 100644
--- a/api/test/window_post.go
+++ b/api/test/window_post.go
@@ -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)
 
@@ -159,7 +189,7 @@ func TestWindowPost(t *testing.T, b APIBuilder, blocktime time.Duration, nSector
 		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
 		}
@@ -289,12 +319,11 @@ 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 {
@@ -315,7 +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
 }
diff --git a/build/params_2k.go b/build/params_2k.go
index 3682f7be1..f4a17f724 100644
--- a/build/params_2k.go
+++ b/build/params_2k.go
@@ -14,6 +14,7 @@ const BreezeGasTampingDuration = 0
 const UpgradeSmokeHeight = -1
 const UpgradeIgnitionHeight = -2
 const UpgradeLiftoffHeight = -3
+const UpgradeActorsV2Height = 10
 
 var DrandSchedule = map[abi.ChainEpoch]DrandEnum{
 	0: DrandMainnet,
diff --git a/build/params_shared_funcs.go b/build/params_shared_funcs.go
index 28567d3d1..40ccca50b 100644
--- a/build/params_shared_funcs.go
+++ b/build/params_shared_funcs.go
@@ -41,7 +41,7 @@ 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
diff --git a/build/params_shared_vals.go b/build/params_shared_vals.go
index 33828f954..4734a15ed 100644
--- a/build/params_shared_vals.go
+++ b/build/params_shared_vals.go
@@ -7,12 +7,12 @@ import (
 	"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"
 )
 
 // /////
@@ -25,7 +25,7 @@ const UnixfsLinksPerLevel = 1024
 // Consensus / Network
 
 const AllowableClockDriftSecs = uint64(1)
-const NewestNetworkVersion = network.Version3
+const NewestNetworkVersion = network.Version4
 const ActorUpgradeNetworkVersion = network.Version4
 
 // Epochs
@@ -35,7 +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
@@ -47,13 +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
diff --git a/build/params_testground.go b/build/params_testground.go
index 07cc88688..6d51100e4 100644
--- a/build/params_testground.go
+++ b/build/params_testground.go
@@ -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
@@ -47,9 +48,7 @@ var (
 	BlsSignatureCacheSize = 40000
 	VerifSigCacheSize     = 32000
 
-	SealRandomnessLookback      = Finality
-	SealRandomnessLookbackLimit = SealRandomnessLookback + 2000
-	MaxSealLookback             = SealRandomnessLookbackLimit + 2000
+	SealRandomnessLookback = policy.SealRandomnessLookback
 
 	TicketRandomnessLookback     = abi.ChainEpoch(1)
 	WinningPoStSectorSetLookback = abi.ChainEpoch(10)
@@ -77,13 +76,14 @@ var (
 	UpgradeSmokeHeight    abi.ChainEpoch = -1
 	UpgradeIgnitionHeight abi.ChainEpoch = -2
 	UpgradeLiftoffHeight  abi.ChainEpoch = -3
+	UpgradeActorsV2Height abi.ChainEpoch = 10
 
 	DrandSchedule = map[abi.ChainEpoch]DrandEnum{
 		0: DrandMainnet,
 	}
 
-	NewestNetworkVersion       = network.Version2
-	ActorUpgradeNetworkVersion = network.Version3
+	NewestNetworkVersion       = network.Version4
+	ActorUpgradeNetworkVersion = network.Version4
 
 	Devnet = true
 )
diff --git a/build/params_testnet.go b/build/params_testnet.go
index 960f3a9b6..0aa77788b 100644
--- a/build/params_testnet.go
+++ b/build/params_testnet.go
@@ -23,6 +23,9 @@ const UpgradeSmokeHeight = 51000
 
 const UpgradeIgnitionHeight = 94000
 
+// TODO: Actual epoch needs to be filled in
+const UpgradeActorsV2Height = 128888
+
 // 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.
diff --git a/chain/actors/adt/adt.go b/chain/actors/adt/adt.go
index 39dd5cebc..6a454ac26 100644
--- a/chain/actors/adt/adt.go
+++ b/chain/actors/adt/adt.go
@@ -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)
 }
diff --git a/chain/actors/builtin/account/account.go b/chain/actors/builtin/account/account.go
index 5b90580ec..7b1b2a792 100644
--- a/chain/actors/builtin/account/account.go
+++ b/chain/actors/builtin/account/account.go
@@ -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)
 }
diff --git a/chain/actors/builtin/account/v0.go b/chain/actors/builtin/account/v0.go
index 30bafbfd3..67c555c5d 100644
--- a/chain/actors/builtin/account/v0.go
+++ b/chain/actors/builtin/account/v0.go
@@ -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
 }
 
diff --git a/chain/actors/builtin/account/v2.go b/chain/actors/builtin/account/v2.go
new file mode 100644
index 000000000..2664631bc
--- /dev/null
+++ b/chain/actors/builtin/account/v2.go
@@ -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
+}
diff --git a/chain/actors/builtin/builtin.go b/chain/actors/builtin/builtin.go
index a85b4da65..d49164486 100644
--- a/chain/actors/builtin/builtin.go
+++ b/chain/actors/builtin/builtin.go
@@ -1,32 +1,25 @@
 package builtin
 
 import (
-	"fmt"
+	"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, network.Version3:
-		return Version0
-	default:
-		panic(fmt.Sprintf("unsupported network version %d", version))
-	}
-}
+var SystemActorAddr = builtin0.SystemActorAddr
+var BurntFundsActorAddr = builtin0.BurntFundsActorAddr
 
 // TODO: Why does actors have 2 different versions of this?
 type SectorInfo = proof0.SectorInfo
@@ -41,3 +34,55 @@ 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
+}
diff --git a/chain/actors/builtin/init/init.go b/chain/actors/builtin/init/init.go
index f235450c2..5777bb890 100644
--- a/chain/actors/builtin/init/init.go
+++ b/chain/actors/builtin/init/init.go
@@ -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
 }
diff --git a/chain/actors/builtin/init/v0.go b/chain/actors/builtin/init/v0.go
index 425ba654c..ceb87f970 100644
--- a/chain/actors/builtin/init/v0.go
+++ b/chain/actors/builtin/init/v0.go
@@ -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 {
diff --git a/chain/actors/builtin/init/v2.go b/chain/actors/builtin/init/v2.go
new file mode 100644
index 000000000..5aa0ddc18
--- /dev/null
+++ b/chain/actors/builtin/init/v2.go
@@ -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
+}
diff --git a/chain/actors/builtin/market/market.go b/chain/actors/builtin/market/market.go
index fef0c03f9..fd08a0119 100644
--- a/chain/actors/builtin/market/market.go
+++ b/chain/actors/builtin/market/market.go
@@ -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)
 }
diff --git a/chain/actors/builtin/market/v0.go b/chain/actors/builtin/market/v0.go
index 2727f513d..20d38b5f1 100644
--- a/chain/actors/builtin/market/v0.go
+++ b/chain/actors/builtin/market/v0.go
@@ -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)
 }
diff --git a/chain/actors/builtin/market/v2.go b/chain/actors/builtin/market/v2.go
new file mode 100644
index 000000000..a5e5c7b45
--- /dev/null
+++ b/chain/actors/builtin/market/v2.go
@@ -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)
+}
diff --git a/chain/actors/builtin/miner/miner.go b/chain/actors/builtin/miner/miner.go
index 5ea5cfc81..125d142d3 100644
--- a/chain/actors/builtin/miner/miner.go
+++ b/chain/actors/builtin/miner/miner.go
@@ -11,14 +11,26 @@ 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
+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
@@ -30,12 +42,9 @@ 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)
 }
diff --git a/chain/actors/builtin/miner/v0.go b/chain/actors/builtin/miner/v0.go
index f5aa7849d..902ed20f2 100644
--- a/chain/actors/builtin/miner/v0.go
+++ b/chain/actors/builtin/miner/v0.go
@@ -4,22 +4,32 @@ import (
 	"bytes"
 	"errors"
 
-	"github.com/libp2p/go-libp2p-core/peer"
-	cbg "github.com/whyrusleeping/cbor-gen"
-	"golang.org/x/xerrors"
-
 	"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
diff --git a/chain/actors/builtin/miner/v2.go b/chain/actors/builtin/miner/v2.go
new file mode 100644
index 000000000..934554d23
--- /dev/null
+++ b/chain/actors/builtin/miner/v2.go
@@ -0,0 +1,402 @@
+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), nil
+}
+
+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) 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,
+	}
+
+	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,
+	}
+}
diff --git a/chain/actors/builtin/multisig/message.go b/chain/actors/builtin/multisig/message.go
new file mode 100644
index 000000000..b19287432
--- /dev/null
+++ b/chain/actors/builtin/multisig/message.go
@@ -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)
+}
diff --git a/chain/actors/builtin/multisig/message0.go b/chain/actors/builtin/multisig/message0.go
new file mode 100644
index 000000000..dc43a9d5d
--- /dev/null
+++ b/chain/actors/builtin/multisig/message0.go
@@ -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
+}
diff --git a/chain/actors/builtin/multisig/message2.go b/chain/actors/builtin/multisig/message2.go
new file mode 100644
index 000000000..da2700d06
--- /dev/null
+++ b/chain/actors/builtin/multisig/message2.go
@@ -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
+}
diff --git a/chain/actors/builtin/multisig/multisig.go b/chain/actors/builtin/multisig/state.go
similarity index 64%
rename from chain/actors/builtin/multisig/multisig.go
rename to chain/actors/builtin/multisig/state.go
index 884b6f493..89a7eedad 100644
--- a/chain/actors/builtin/multisig/multisig.go
+++ b/chain/actors/builtin/multisig/state.go
@@ -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)
 }
diff --git a/chain/actors/builtin/multisig/v0.go b/chain/actors/builtin/multisig/state0.go
similarity index 87%
rename from chain/actors/builtin/multisig/v0.go
rename to chain/actors/builtin/multisig/state0.go
index ae0a7ac0e..c934343e7 100644
--- a/chain/actors/builtin/multisig/v0.go
+++ b/chain/actors/builtin/multisig/state0.go
@@ -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
diff --git a/chain/actors/builtin/multisig/state2.go b/chain/actors/builtin/multisig/state2.go
new file mode 100644
index 000000000..a78b07d55
--- /dev/null
+++ b/chain/actors/builtin/multisig/state2.go
@@ -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))
+	})
+}
diff --git a/chain/actors/builtin/paych/message.go b/chain/actors/builtin/paych/message.go
new file mode 100644
index 000000000..23b360394
--- /dev/null
+++ b/chain/actors/builtin/paych/message.go
@@ -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)
+}
diff --git a/chain/actors/builtin/paych/message0.go b/chain/actors/builtin/paych/message0.go
new file mode 100644
index 000000000..bfeb2731e
--- /dev/null
+++ b/chain/actors/builtin/paych/message0.go
@@ -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
+}
diff --git a/chain/actors/builtin/paych/message2.go b/chain/actors/builtin/paych/message2.go
new file mode 100644
index 000000000..2cf3ef22e
--- /dev/null
+++ b/chain/actors/builtin/paych/message2.go
@@ -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
+}
diff --git a/chain/actors/builtin/paych/paych.go b/chain/actors/builtin/paych/state.go
similarity index 62%
rename from chain/actors/builtin/paych/paych.go
rename to chain/actors/builtin/paych/state.go
index dad54163f..20c7a74b7 100644
--- a/chain/actors/builtin/paych/paych.go
+++ b/chain/actors/builtin/paych/state.go
@@ -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
+}
diff --git a/chain/actors/builtin/paych/v0.go b/chain/actors/builtin/paych/state0.go
similarity index 83%
rename from chain/actors/builtin/paych/v0.go
rename to chain/actors/builtin/paych/state0.go
index c0eea1000..8e0e3434e 100644
--- a/chain/actors/builtin/paych/v0.go
+++ b/chain/actors/builtin/paych/state0.go
@@ -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) {
diff --git a/chain/actors/builtin/paych/state2.go b/chain/actors/builtin/paych/state2.go
new file mode 100644
index 000000000..fbf4b9fde
--- /dev/null
+++ b/chain/actors/builtin/paych/state2.go
@@ -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
+}
diff --git a/chain/actors/builtin/power/power.go b/chain/actors/builtin/power/power.go
index e4bb52d44..e683cfd96 100644
--- a/chain/actors/builtin/power/power.go
+++ b/chain/actors/builtin/power/power.go
@@ -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)
 }
diff --git a/chain/actors/builtin/power/v0.go b/chain/actors/builtin/power/v0.go
index f2fe96dad..e2a9cf382 100644
--- a/chain/actors/builtin/power/v0.go
+++ b/chain/actors/builtin/power/v0.go
@@ -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
 	}
diff --git a/chain/actors/builtin/power/v2.go b/chain/actors/builtin/power/v2.go
new file mode 100644
index 000000000..6346a09b6
--- /dev/null
+++ b/chain/actors/builtin/power/v2.go
@@ -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
+}
diff --git a/chain/actors/builtin/reward/reward.go b/chain/actors/builtin/reward/reward.go
index cfa82c774..065f242e2 100644
--- a/chain/actors/builtin/reward/reward.go
+++ b/chain/actors/builtin/reward/reward.go
@@ -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)
 }
diff --git a/chain/actors/builtin/reward/v0.go b/chain/actors/builtin/reward/v0.go
index df7117b67..0efd0b482 100644
--- a/chain/actors/builtin/reward/v0.go
+++ b/chain/actors/builtin/reward/v0.go
@@ -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,
 		},
diff --git a/chain/actors/builtin/reward/v2.go b/chain/actors/builtin/reward/v2.go
new file mode 100644
index 000000000..ec0709c39
--- /dev/null
+++ b/chain/actors/builtin/reward/v2.go
@@ -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
+}
diff --git a/chain/actors/builtin/verifreg/util.go b/chain/actors/builtin/verifreg/util.go
new file mode 100644
index 000000000..4136c0c30
--- /dev/null
+++ b/chain/actors/builtin/verifreg/util.go
@@ -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)
+	})
+}
diff --git a/chain/actors/builtin/verifreg/v0.go b/chain/actors/builtin/verifreg/v0.go
index 51ed3b456..64def4706 100644
--- a/chain/actors/builtin/verifreg/v0.go
+++ b/chain/actors/builtin/verifreg/v0.go
@@ -3,73 +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)
 }
diff --git a/chain/actors/builtin/verifreg/v2.go b/chain/actors/builtin/verifreg/v2.go
new file mode 100644
index 000000000..5ee3bad05
--- /dev/null
+++ b/chain/actors/builtin/verifreg/v2.go
@@ -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)
+}
diff --git a/chain/actors/builtin/verifreg/verifreg.go b/chain/actors/builtin/verifreg/verifreg.go
index 95a60d1d9..204cdae95 100644
--- a/chain/actors/builtin/verifreg/verifreg.go
+++ b/chain/actors/builtin/verifreg/verifreg.go
@@ -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)
 }
diff --git a/chain/actors/policy/policy.go b/chain/actors/policy/policy.go
index b8205177e..f29da9802 100644
--- a/chain/actors/policy/policy.go
+++ b/chain/actors/policy/policy.go
@@ -2,10 +2,22 @@ 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.
@@ -17,6 +29,7 @@ func SetSupportedProofTypes(types ...abi.RegisteredSealProof) {
 	}
 	// Set for all miner versions.
 	miner0.SupportedProofTypes = newTypes
+	miner2.SupportedProofTypes = newTypes
 }
 
 // AddSupportedProofTypes sets supported proof types, across all actor versions.
@@ -25,6 +38,7 @@ func AddSupportedProofTypes(types ...abi.RegisteredSealProof) {
 	for _, t := range types {
 		// Set for all miner versions.
 		miner0.SupportedProofTypes[t] = struct{}{}
+		miner2.SupportedProofTypes[t] = struct{}{}
 	}
 }
 
@@ -33,6 +47,7 @@ func AddSupportedProofTypes(types ...abi.RegisteredSealProof) {
 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.
@@ -45,10 +60,50 @@ func GetPreCommitChallengeDelay() abi.ChainEpoch {
 // 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)
 }
diff --git a/chain/actors/policy/policy_test.go b/chain/actors/policy/policy_test.go
index be64362a2..62e7f8964 100644
--- a/chain/actors/policy/policy_test.go
+++ b/chain/actors/policy/policy_test.go
@@ -7,6 +7,9 @@ import (
 
 	"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) {
@@ -34,3 +37,14 @@ func TestSupportedProofTypes(t *testing.T) {
 		},
 	)
 }
+
+// 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))
+}
diff --git a/chain/actors/version.go b/chain/actors/version.go
new file mode 100644
index 000000000..385ff592f
--- /dev/null
+++ b/chain/actors/version.go
@@ -0,0 +1,26 @@
+package actors
+
+import (
+	"fmt"
+
+	"github.com/filecoin-project/go-state-types/network"
+)
+
+type Version int
+
+const (
+	Version0 = 0
+	Version2 = 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))
+	}
+}
diff --git a/chain/gen/gen.go b/chain/gen/gen.go
index d05165ab1..3ebd127f3 100644
--- a/chain/gen/gen.go
+++ b/chain/gen/gen.go
@@ -9,6 +9,7 @@ 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"
@@ -224,7 +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()),
 	}
 
diff --git a/chain/gen/genesis/genesis.go b/chain/gen/genesis/genesis.go
index 039e284cd..bb1056e2e 100644
--- a/chain/gen/genesis/genesis.go
+++ b/chain/gen/genesis/genesis.go
@@ -24,7 +24,7 @@ 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/actors"
 	"github.com/filecoin-project/lotus/chain/state"
 	"github.com/filecoin-project/lotus/chain/store"
 	"github.com/filecoin-project/lotus/chain/types"
@@ -115,7 +115,7 @@ 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, actors.Version0)
 	if err != nil {
 		return nil, nil, xerrors.Errorf("making new state tree: %w", err)
 	}
diff --git a/chain/messagepool/gasguess/guessgas.go b/chain/messagepool/gasguess/guessgas.go
index af58db7d2..607c7824a 100644
--- a/chain/messagepool/gasguess/guessgas.go
+++ b/chain/messagepool/gasguess/guessgas.go
@@ -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
diff --git a/chain/state/statetree.go b/chain/state/statetree.go
index fe932bfa1..3f9597420 100644
--- a/chain/state/statetree.go
+++ b/chain/state/statetree.go
@@ -13,7 +13,7 @@ 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/lotus/chain/actors"
 	init_ "github.com/filecoin-project/lotus/chain/actors/builtin/init"
 	cbg "github.com/whyrusleeping/cbor-gen"
 
@@ -26,7 +26,7 @@ var log = logging.Logger("statetree")
 // StateTree stores actors state by their ID.
 type StateTree struct {
 	root    adt.Map
-	version builtin.Version // TODO
+	version actors.Version // TODO
 	info    cid.Cid
 	Store   cbor.IpldStore
 
@@ -120,11 +120,17 @@ 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) {
+func NewStateTree(cst cbor.IpldStore, version actors.Version) (*StateTree, error) {
 	var info cid.Cid
 	switch version {
-	case builtin.Version0:
+	case actors.Version0:
 		// info is undefined
+	case actors.Version2:
+		var err error
+		info, err = cst.Put(context.TODO(), new(types.StateInfo))
+		if err != nil {
+			return nil, err
+		}
 	default:
 		return nil, xerrors.Errorf("unsupported state tree version: %d", version)
 	}
@@ -148,30 +154,28 @@ 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 = actors.Version0
 	}
 
 	switch root.Version {
-	case builtin.Version0:
-		// supported
+	case actors.Version0, actors.Version2:
+		// Load the actual state-tree HAMT.
+		nd, err := adt.AsMap(adt.WrapStore(context.TODO(), cst), root.Actors, actors.Version(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: actors.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 {
@@ -305,7 +309,7 @@ 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 == actors.Version0 {
 		return root, nil
 	}
 	// Otherwise, return a versioned tree.
@@ -396,7 +400,7 @@ 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() builtin.Version {
+func (st *StateTree) Version() actors.Version {
 	return st.version
 }
 
diff --git a/chain/state/statetree_test.go b/chain/state/statetree_test.go
index 79ab20606..3b08a4b53 100644
--- a/chain/state/statetree_test.go
+++ b/chain/state/statetree_test.go
@@ -9,16 +9,17 @@ 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/actors"
 	"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, actors.VersionForNetwork(build.NewestNetworkVersion))
 	if err != nil {
 		b.Fatal(err)
 	}
@@ -45,7 +46,7 @@ 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, actors.VersionForNetwork(build.NewestNetworkVersion))
 	if err != nil {
 		b.Fatal(err)
 	}
@@ -75,7 +76,7 @@ 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, actors.VersionForNetwork(build.NewestNetworkVersion))
 	if err != nil {
 		b.Fatal(err)
 	}
@@ -117,7 +118,7 @@ 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, actors.VersionForNetwork(build.NewestNetworkVersion))
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -154,7 +155,7 @@ 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, actors.VersionForNetwork(build.NewestNetworkVersion))
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -237,7 +238,8 @@ 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, actors.VersionForNetwork(network.Version3))
 	if err != nil {
 		t.Fatal(err)
 	}
diff --git a/chain/stmgr/call.go b/chain/stmgr/call.go
index f4dfc7115..15cbac53e 100644
--- a/chain/stmgr/call.go
+++ b/chain/stmgr/call.go
@@ -5,7 +5,6 @@ import (
 	"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 +17,26 @@ 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")
+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 ts == nil {
+		ts = sm.cs.GetHeaviestTipSet()
+	}
+
+	bstate := ts.ParentState()
+	bheight := ts.Height()
+
+	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,
@@ -89,18 +100,6 @@ 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()
@@ -114,6 +113,11 @@ 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() {
diff --git a/chain/stmgr/forks.go b/chain/stmgr/forks.go
index 252b731d7..d5d0dbf7e 100644
--- a/chain/stmgr/forks.go
+++ b/chain/stmgr/forks.go
@@ -6,43 +6,108 @@ import (
 	"encoding/binary"
 	"math"
 
-	multisig0 "github.com/filecoin-project/specs-actors/actors/builtin/multisig"
-
-	"github.com/filecoin-project/lotus/chain/actors/builtin/multisig"
-
-	"github.com/filecoin-project/lotus/chain/state"
-
-	"github.com/filecoin-project/specs-actors/actors/migration/nv3"
-
-	"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/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"
-	init0 "github.com/filecoin-project/specs-actors/actors/builtin/init"
 	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"
+	"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/types"
 	"github.com/filecoin-project/lotus/chain/vm"
-	cbor "github.com/ipfs/go-ipld-cbor"
-	"golang.org/x/xerrors"
 )
 
-var ForksAtHeight = map[abi.ChainEpoch]func(context.Context, *StateManager, ExecCallback, cid.Cid, *types.TipSet) (cid.Cid, error){
-	build.UpgradeBreezeHeight:   UpgradeFaucetBurnRecovery,
-	build.UpgradeIgnitionHeight: UpgradeIgnition,
-	build.UpgradeLiftoffHeight:  UpgradeLiftoff,
+type UpgradeFunc func(context.Context, *StateManager, ExecCallback, cid.Cid, *types.TipSet) (cid.Cid, error)
+
+type Upgrade struct {
+	Height    abi.ChainEpoch
+	Network   network.Version
+	Migration UpgradeFunc
+}
+
+type UpgradeSchedule []Upgrade
+
+func DefaultUpgradeSchedule() UpgradeSchedule {
+	var us UpgradeSchedule
+
+	for _, u := range []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.UpgradeActorsV2Height,
+		Network:   network.Version4,
+		Migration: UpgradeActorsV2,
+	}, {
+		Height:    build.UpgradeLiftoffHeight,
+		Network:   network.Version4,
+		Migration: UpgradeLiftoff,
+	}} {
+		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
 }
 
 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 := ForksAtHeight[height]
+	f, ok := sm.stateMigrations[height]
 	if ok {
 		retCid, err = f(ctx, sm, cb, root, ts)
 		if err != nil {
@@ -370,7 +435,13 @@ func UpgradeFaucetBurnRecovery(ctx context.Context, sm *StateManager, cb ExecCal
 func UpgradeIgnition(ctx context.Context, sm *StateManager, cb ExecCallback, root cid.Cid, ts *types.TipSet) (cid.Cid, error) {
 	store := sm.cs.Store(ctx)
 
-	nst, err := nv3.MigrateStateTree(ctx, store, root, build.UpgradeIgnitionHeight)
+	epoch := ts.Height() - 1
+
+	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)
 	}
@@ -395,7 +466,7 @@ func UpgradeIgnition(ctx context.Context, sm *StateManager, cb ExecCallback, roo
 		return cid.Undef, xerrors.Errorf("second split address: %w", err)
 	}
 
-	err = resetGenesisMsigs(ctx, sm, store, tree)
+	err = resetGenesisMsigs(ctx, sm, store, tree, build.UpgradeLiftoffHeight)
 	if err != nil {
 		return cid.Undef, xerrors.Errorf("resetting genesis msig start epochs: %w", err)
 	}
@@ -410,7 +481,7 @@ func UpgradeIgnition(ctx context.Context, sm *StateManager, cb ExecCallback, roo
 		return cid.Undef, xerrors.Errorf("splitting second msig: %w", err)
 	}
 
-	err = nv3.CheckStateTree(ctx, store, nst, build.UpgradeIgnitionHeight, builtin0.TotalFilecoin)
+	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)
 	}
@@ -418,6 +489,58 @@ func UpgradeIgnition(ctx context.Context, sm *StateManager, cb ExecCallback, roo
 	return tree.Flush(ctx)
 }
 
+func UpgradeActorsV2(ctx context.Context, sm *StateManager, cb ExecCallback, root cid.Cid, ts *types.TipSet) (cid.Cid, error) {
+	store := sm.cs.Store(ctx)
+
+	epoch := ts.Height() - 1
+
+	info, err := store.Put(ctx, new(types.StateInfo))
+	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{
+		// TODO: ActorUpgrade: should be state-tree specific, not just the actors version.
+		Version: actors.Version2,
+		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)
+	}
+
+	return newRoot, nil
+}
+
 func UpgradeLiftoff(ctx context.Context, sm *StateManager, cb ExecCallback, root cid.Cid, ts *types.TipSet) (cid.Cid, error) {
 	tree, err := sm.StateTree(root)
 	if err != nil {
@@ -432,20 +555,22 @@ func UpgradeLiftoff(ctx context.Context, sm *StateManager, cb ExecCallback, root
 	return tree.Flush(ctx)
 }
 
-func setNetworkName(ctx context.Context, store adt0.Store, tree *state.StateTree, name string) error {
+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)
 	}
 
-	var initState init0.State
-	if err := store.Get(ctx, ia.Head, &initState); err != nil {
+	initState, err := init_.Load(store, ia)
+	if err != nil {
 		return xerrors.Errorf("reading init state: %w", err)
 	}
 
-	initState.NetworkName = name
+	if err := initState.SetNetworkName(name); err != nil {
+		return xerrors.Errorf("setting network name: %w", err)
+	}
 
-	ia.Head, err = store.Put(ctx, &initState)
+	ia.Head, err = store.Put(ctx, initState)
 	if err != nil {
 		return xerrors.Errorf("writing new init state: %w", err)
 	}
@@ -574,7 +699,7 @@ func makeKeyAddr(splitAddr address.Address, count uint64) (address.Address, erro
 	return addr, nil
 }
 
-func resetGenesisMsigs(ctx context.Context, sm *StateManager, store adt0.Store, tree *state.StateTree) error {
+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)
@@ -603,7 +728,7 @@ func resetGenesisMsigs(ctx context.Context, sm *StateManager, store adt0.Store,
 				return xerrors.Errorf("reading multisig state: %w", err)
 			}
 
-			currState.StartEpoch = build.UpgradeLiftoffHeight
+			currState.StartEpoch = startEpoch
 
 			currActor.Head, err = store.Put(ctx, &currState)
 			if err != nil {
diff --git a/chain/stmgr/forks_test.go b/chain/stmgr/forks_test.go
index a3423ccdd..bb03f13b9 100644
--- a/chain/stmgr/forks_test.go
+++ b/chain/stmgr/forks_test.go
@@ -8,6 +8,7 @@ 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/filecoin-project/specs-actors/actors/builtin"
 	init_ "github.com/filecoin-project/specs-actors/actors/builtin/init"
 	"github.com/filecoin-project/specs-actors/actors/runtime"
@@ -18,7 +19,6 @@ import (
 	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"
@@ -26,7 +26,7 @@ import (
 	_ "github.com/filecoin-project/lotus/lib/sigs/secp"
 
 	"github.com/ipfs/go-cid"
-	cbor "github.com/ipfs/go-ipld-cbor"
+	ipldcbor "github.com/ipfs/go-ipld-cbor"
 	logging "github.com/ipfs/go-log"
 	cbg "github.com/whyrusleeping/cbor-gen"
 )
@@ -42,6 +42,10 @@ 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
 }
@@ -62,7 +66,7 @@ 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,
@@ -105,51 +109,57 @@ 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, cb ExecCallback, root cid.Cid, ts *types.TipSet) (cid.Cid, 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, ts *types.TipSet) (cid.Cid, error) {
+				cst := ipldcbor.NewCborStore(sm.ChainStore().Blockstore())
 
-		st, err := sm.StateTree(root)
-		if err != nil {
-			return cid.Undef, xerrors.Errorf("getting state tree: %w", err)
-		}
+				st, err := sm.StateTree(root)
+				if err != nil {
+					return cid.Undef, xerrors.Errorf("getting state tree: %w", err)
+				}
 
-		act, err := st.GetActor(taddr)
-		if err != nil {
-			return cid.Undef, err
-		}
+				act, err := st.GetActor(taddr)
+				if err != nil {
+					return cid.Undef, err
+				}
 
-		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)
-		}
+				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)
+				}
 
-		tas.HasUpgraded = 55
+				tas.HasUpgraded = 55
 
-		ns, err := cst.Put(ctx, &tas)
-		if err != nil {
-			return cid.Undef, err
-		}
+				ns, err := cst.Put(ctx, &tas)
+				if err != nil {
+					return cid.Undef, err
+				}
 
-		act.Head = ns
+				act.Head = ns
 
-		if err := st.SetActor(taddr, act); err != nil {
-			return cid.Undef, err
-		}
+				if err := st.SetActor(taddr, act); err != nil {
+					return cid.Undef, err
+				}
 
-		return st.Flush(ctx)
+				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 {
@@ -163,7 +173,7 @@ func TestForkHeightTriggers(t *testing.T) {
 
 	var msgs []*types.SignedMessage
 
-	enc, err := actors.SerializeParams(&init_.ExecParams{CodeCID: builtin.PaymentChannelActorCodeID})
+	enc, err := actors.SerializeParams(&init_.ExecParams{CodeCID: (testActor{}).Code()})
 	if err != nil {
 		t.Fatal(err)
 	}
diff --git a/chain/stmgr/stmgr.go b/chain/stmgr/stmgr.go
index 90e43ebbc..e371992e8 100644
--- a/chain/stmgr/stmgr.go
+++ b/chain/stmgr/stmgr.go
@@ -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"
@@ -38,9 +39,21 @@ import (
 
 var log = logging.Logger("statemgr")
 
+type versionSpec struct {
+	networkVersion network.Version
+	atOrBelow      abi.ChainEpoch
+}
+
 type StateManager struct {
 	cs *store.ChainStore
 
+	// Determines the network version at any given epoch.
+	networkVersions []versionSpec
+	latestVersion   network.Version
+
+	// Maps chain epochs to upgrade functions.
+	stateMigrations map[abi.ChainEpoch]UpgradeFunc
+
 	stCache              map[string][]cid.Cid
 	compWait             map[string]chan struct{}
 	stlk                 sync.Mutex
@@ -51,12 +64,49 @@ type StateManager struct {
 }
 
 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))
+	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
+			}
+			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,
+		newVM:           vm.NewVM,
+		cs:              cs,
+		stCache:         make(map[string][]cid.Cid),
+		compWait:        make(map[string]chan struct{}),
+	}, nil
 }
 
 func cidsToKey(cids []cid.Cid) string {
@@ -279,7 +329,7 @@ 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{
@@ -295,7 +345,7 @@ 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 {
@@ -313,7 +363,7 @@ 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)
 	}
@@ -859,7 +909,7 @@ 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
@@ -891,7 +941,7 @@ 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 {
@@ -1258,25 +1308,14 @@ 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
-	}
-
-	if height <= build.UpgradeIgnitionHeight {
-		return network.Version2
-	}
-
-	return build.NewestNetworkVersion
+	return sm.latestVersion
 }
 
 func (sm *StateManager) GetPaychState(ctx context.Context, addr address.Address, ts *types.TipSet) (*types.Actor, paych.State, error) {
diff --git a/chain/stmgr/utils.go b/chain/stmgr/utils.go
index bac5a31f5..98f6bc5ac 100644
--- a/chain/stmgr/utils.go
+++ b/chain/stmgr/utils.go
@@ -17,19 +17,12 @@ 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"
@@ -534,42 +527,23 @@ 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 {
@@ -580,22 +554,19 @@ 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")
 				}
@@ -607,7 +578,7 @@ func init() {
 				Ret:    et.Out(0),
 			}
 		}
-		MethodsMap[c] = methods
+		MethodsMap[actor.Code()] = methods
 	}
 }
 
diff --git a/chain/store/basefee.go b/chain/store/basefee.go
index 45785240e..33367abcc 100644
--- a/chain/store/basefee.go
+++ b/chain/store/basefee.go
@@ -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
 	}
 
diff --git a/chain/store/basefee_test.go b/chain/store/basefee_test.go
index b4757f70e..b3d414cf5 100644
--- a/chain/store/basefee_test.go
+++ b/chain/store/basefee_test.go
@@ -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())
 		})
 	}
 }
diff --git a/chain/store/store.go b/chain/store/store.go
index 0c99b9d43..aac28e5d3 100644
--- a/chain/store/store.go
+++ b/chain/store/store.go
@@ -17,11 +17,13 @@ import (
 
 	"github.com/filecoin-project/go-address"
 	"github.com/filecoin-project/go-state-types/abi"
+
 	"github.com/filecoin-project/specs-actors/actors/builtin"
-	"github.com/filecoin-project/specs-actors/actors/util/adt"
+	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"
@@ -757,7 +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)
 	}
@@ -950,7 +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)
 	}
diff --git a/chain/sub/incoming.go b/chain/sub/incoming.go
index 0c72b4d80..53bc3d68e 100644
--- a/chain/sub/incoming.go
+++ b/chain/sub/incoming.go
@@ -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"
@@ -384,9 +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)
diff --git a/chain/sync.go b/chain/sync.go
index b2e3bb7f1..46d3934b1 100644
--- a/chain/sync.go
+++ b/chain/sync.go
@@ -11,6 +11,8 @@ 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"
@@ -33,9 +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"
@@ -455,9 +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)
@@ -1087,7 +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
@@ -1101,9 +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)
@@ -1115,7 +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)
diff --git a/chain/types/actor.go b/chain/types/actor.go
index eb8e05c49..a9974a01f 100644
--- a/chain/types/actor.go
+++ b/chain/types/actor.go
@@ -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
-}
diff --git a/chain/types/voucher.go b/chain/types/voucher.go
deleted file mode 100644
index 687109c33..000000000
--- a/chain/types/voucher.go
+++ /dev/null
@@ -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
-}
diff --git a/chain/vectors/gen/main.go b/chain/vectors/gen/main.go
index 2b1c6f340..51d907648 100644
--- a/chain/vectors/gen/main.go
+++ b/chain/vectors/gen/main.go
@@ -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 {
diff --git a/chain/vm/gas.go b/chain/vm/gas.go
index 12acf6a21..6802013e5 100644
--- a/chain/vm/gas.go
+++ b/chain/vm/gas.go
@@ -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)
 
diff --git a/chain/vm/gas_v0.go b/chain/vm/gas_v0.go
index e5ded440e..bfb49c345 100644
--- a/chain/vm/gas_v0.go
+++ b/chain/vm/gas_v0.go
@@ -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
diff --git a/chain/vm/invoker.go b/chain/vm/invoker.go
index 0a83e273d..1e9f04081 100644
--- a/chain/vm/invoker.go
+++ b/chain/vm/invoker.go
@@ -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 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)
-
-}
-
-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))
+	if err := act.predicate(rt, act.vmActor); err != nil {
+		return nil, aerrors.Newf(exitcode.SysErrInvalidMethod, "unsupported actor: %s", err)
 	}
-	inv.builtInCode[c] = code
-	inv.builtInState[c] = reflect.TypeOf(state)
+	return act.methods[method](rt, params)
+
 }
 
-type Invokee interface {
+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,
+		}
+	}
+}
+
+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
 }
diff --git a/chain/vm/invoker_test.go b/chain/vm/invoker_test.go
index 3744aa8d2..4005dd42f 100644
--- a/chain/vm/invoker_test.go
+++ b/chain/vm/invoker_test.go
@@ -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)
 
diff --git a/chain/vm/mkactor.go b/chain/vm/mkactor.go
index 43d2f9431..33884368f 100644
--- a/chain/vm/mkactor.go
+++ b/chain/vm/mkactor.go
@@ -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"
@@ -39,7 +41,7 @@ func TryCreateAccountActor(rt *Runtime, addr address.Address) (*types.Actor, aer
 		return nil, aerrors.Escalate(err, "registering actor address")
 	}
 
-	act, aerr := makeActor(addr)
+	act, aerr := makeActor(actors.VersionForNetwork(rt.NetworkVersion()), addr)
 	if aerr != nil {
 		return nil, aerr
 	}
@@ -54,7 +56,7 @@ func TryCreateAccountActor(rt *Runtime, addr address.Address) (*types.Actor, aer
 	}
 	// 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")
 	}
@@ -66,12 +68,10 @@ func TryCreateAccountActor(rt *Runtime, addr address.Address) (*types.Actor, aer
 	return act, 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,
 	}
diff --git a/chain/vm/runtime.go b/chain/vm/runtime.go
index 72dd413ed..472017a00 100644
--- a/chain/vm/runtime.go
+++ b/chain/vm/runtime.go
@@ -9,14 +9,13 @@ 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/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"
@@ -110,6 +109,7 @@ 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() {
@@ -215,12 +215,9 @@ 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)
@@ -230,12 +227,7 @@ 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))
 	}
diff --git a/chain/vm/vm.go b/chain/vm/vm.go
index 44979454f..1361c6fbe 100644
--- a/chain/vm/vm.go
+++ b/chain/vm/vm.go
@@ -8,6 +8,8 @@ import (
 	"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"
@@ -23,7 +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"
@@ -152,7 +153,7 @@ type VM struct {
 	cst            *cbor.BasicIpldStore
 	buf            *bufbstore.BufferedBS
 	blockHeight    abi.ChainEpoch
-	inv            *Invoker
+	areg           *ActorRegistry
 	rand           Rand
 	circSupplyCalc CircSupplyCalculator
 	ntwkVersion    NtwkVersionGetter
@@ -186,7 +187,7 @@ 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,
@@ -403,7 +404,7 @@ 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{
@@ -741,15 +742,15 @@ 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 {
diff --git a/cli/multisig.go b/cli/multisig.go
index 5b0977382..6b3867cb3 100644
--- a/cli/multisig.go
+++ b/cli/multisig.go
@@ -9,6 +9,10 @@ import (
 	"strconv"
 	"text/tabwriter"
 
+	builtin2 "github.com/filecoin-project/specs-actors/v2/actors/builtin"
+
+	"github.com/filecoin-project/lotus/chain/actors/builtin"
+
 	"github.com/filecoin-project/lotus/chain/actors"
 
 	"github.com/filecoin-project/go-state-types/big"
@@ -20,7 +24,6 @@ import (
 	"github.com/urfave/cli/v2"
 	"golang.org/x/xerrors"
 
-	"github.com/filecoin-project/specs-actors/actors/builtin"
 	init0 "github.com/filecoin-project/specs-actors/actors/builtin/init"
 	msig0 "github.com/filecoin-project/specs-actors/actors/builtin/multisig"
 
@@ -356,7 +359,7 @@ var msigProposeCmd = &cli.Command{
 			return fmt.Errorf("failed to look up multisig %s: %w", msig, err)
 		}
 
-		if !act.IsMultisigActor() {
+		if !builtin.IsMultisigActor(act.Code) {
 			return fmt.Errorf("actor %s is not a multisig actor", msig)
 		}
 
@@ -1029,7 +1032,7 @@ var msigLockProposeCmd = &cli.Command{
 			return actErr
 		}
 
-		msgCid, err := api.MsigPropose(ctx, msig, msig, big.Zero(), from, uint64(builtin.MethodsMultisig.LockBalance), params)
+		msgCid, err := api.MsigPropose(ctx, msig, msig, big.Zero(), from, uint64(builtin2.MethodsMultisig.LockBalance), params)
 		if err != nil {
 			return err
 		}
@@ -1126,7 +1129,7 @@ var msigLockApproveCmd = &cli.Command{
 			return actErr
 		}
 
-		msgCid, err := api.MsigApprove(ctx, msig, txid, prop, msig, big.Zero(), from, uint64(builtin.MethodsMultisig.LockBalance), params)
+		msgCid, err := api.MsigApprove(ctx, msig, txid, prop, msig, big.Zero(), from, uint64(builtin2.MethodsMultisig.LockBalance), params)
 		if err != nil {
 			return err
 		}
@@ -1218,7 +1221,7 @@ var msigLockCancelCmd = &cli.Command{
 			return actErr
 		}
 
-		msgCid, err := api.MsigCancel(ctx, msig, txid, msig, big.Zero(), from, uint64(builtin.MethodsMultisig.LockBalance), params)
+		msgCid, err := api.MsigCancel(ctx, msig, txid, msig, big.Zero(), from, uint64(builtin2.MethodsMultisig.LockBalance), params)
 		if err != nil {
 			return err
 		}
diff --git a/cli/paych.go b/cli/paych.go
index dc5b54c4a..1d5e304c3 100644
--- a/cli/paych.go
+++ b/cli/paych.go
@@ -14,10 +14,10 @@ import (
 
 	"github.com/filecoin-project/go-address"
 	"github.com/filecoin-project/lotus/build"
-	"github.com/filecoin-project/specs-actors/actors/builtin/paych"
 	"github.com/urfave/cli/v2"
 
-	types "github.com/filecoin-project/lotus/chain/types"
+	"github.com/filecoin-project/lotus/chain/actors/builtin/paych"
+	"github.com/filecoin-project/lotus/chain/types"
 )
 
 var paychCmd = &cli.Command{
@@ -404,7 +404,7 @@ var paychVoucherCheckCmd = &cli.Command{
 			return err
 		}
 
-		sv, err := types.DecodeSignedVoucher(cctx.Args().Get(1))
+		sv, err := paych.DecodeSignedVoucher(cctx.Args().Get(1))
 		if err != nil {
 			return err
 		}
@@ -440,7 +440,7 @@ var paychVoucherAddCmd = &cli.Command{
 			return err
 		}
 
-		sv, err := types.DecodeSignedVoucher(cctx.Args().Get(1))
+		sv, err := paych.DecodeSignedVoucher(cctx.Args().Get(1))
 		if err != nil {
 			return err
 		}
@@ -598,7 +598,7 @@ var paychVoucherSubmitCmd = &cli.Command{
 			return err
 		}
 
-		sv, err := types.DecodeSignedVoucher(cctx.Args().Get(1))
+		sv, err := paych.DecodeSignedVoucher(cctx.Args().Get(1))
 		if err != nil {
 			return err
 		}
diff --git a/cli/state.go b/cli/state.go
index 7baf57df2..cb1c974a7 100644
--- a/cli/state.go
+++ b/cli/state.go
@@ -14,7 +14,7 @@ import (
 	"strings"
 	"time"
 
-	"github.com/filecoin-project/specs-actors/actors/runtime"
+	"github.com/filecoin-project/lotus/chain/actors/builtin"
 
 	"github.com/multiformats/go-multiaddr"
 
@@ -30,8 +30,6 @@ import (
 	"github.com/filecoin-project/go-state-types/abi"
 	"github.com/filecoin-project/go-state-types/big"
 	"github.com/filecoin-project/go-state-types/exitcode"
-	"github.com/filecoin-project/specs-actors/actors/builtin"
-	"github.com/filecoin-project/specs-actors/actors/builtin/exported"
 
 	"github.com/filecoin-project/lotus/api"
 	"github.com/filecoin-project/lotus/api/apibstore"
@@ -1534,28 +1532,18 @@ func parseParamsForMethod(act cid.Cid, method uint64, args []string) ([]byte, er
 		return nil, nil
 	}
 
-	var target runtime.Invokee
-	for _, actor := range exported.BuiltinActors() {
-		if actor.Code() == act {
-			target = actor
-		}
-	}
-	if target == nil {
+	// TODO: consider moving this to a dedicated helper
+	actMeta, ok := stmgr.MethodsMap[act]
+	if !ok {
 		return nil, fmt.Errorf("unknown actor %s", act)
 	}
-	methods := target.Exports()
-	if uint64(len(methods)) <= method || methods[method] == nil {
+
+	methodMeta, ok := actMeta[abi.MethodNum(method)]
+	if !ok {
 		return nil, fmt.Errorf("unknown method %d for actor %s", method, act)
 	}
 
-	f := methods[method]
-
-	rf := reflect.TypeOf(f)
-	if rf.NumIn() != 2 {
-		return nil, fmt.Errorf("expected referenced method to have three arguments")
-	}
-
-	paramObj := rf.In(1).Elem()
+	paramObj := methodMeta.Params
 	if paramObj.NumField() != len(args) {
 		return nil, fmt.Errorf("not enough arguments given to call that method (expecting %d)", paramObj.NumField())
 	}
diff --git a/cmd/lotus-chainwatch/processor/common_actors.go b/cmd/lotus-chainwatch/processor/common_actors.go
index 56520880c..0f2c0d2ea 100644
--- a/cmd/lotus-chainwatch/processor/common_actors.go
+++ b/cmd/lotus-chainwatch/processor/common_actors.go
@@ -9,12 +9,15 @@ import (
 
 	"github.com/filecoin-project/go-address"
 	"github.com/filecoin-project/go-state-types/abi"
+	"github.com/ipfs/go-cid"
+
+	builtin2 "github.com/filecoin-project/specs-actors/v2/actors/builtin"
+
+	"github.com/filecoin-project/lotus/chain/actors/builtin"
 	_init "github.com/filecoin-project/lotus/chain/actors/builtin/init"
 	"github.com/filecoin-project/lotus/chain/events/state"
 	"github.com/filecoin-project/lotus/chain/types"
 	cw_util "github.com/filecoin-project/lotus/cmd/lotus-chainwatch/util"
-	"github.com/filecoin-project/specs-actors/actors/builtin"
-	"github.com/ipfs/go-cid"
 )
 
 func (p *Processor) setupCommonActors() error {
@@ -135,15 +138,15 @@ func (p Processor) storeActorAddresses(ctx context.Context, actors map[cid.Cid]A
 
 	addressToID := map[address.Address]address.Address{}
 	// HACK until genesis storage is figured out:
-	addressToID[builtin.SystemActorAddr] = builtin.SystemActorAddr
-	addressToID[builtin.InitActorAddr] = builtin.InitActorAddr
-	addressToID[builtin.RewardActorAddr] = builtin.RewardActorAddr
-	addressToID[builtin.CronActorAddr] = builtin.CronActorAddr
-	addressToID[builtin.StoragePowerActorAddr] = builtin.StoragePowerActorAddr
-	addressToID[builtin.StorageMarketActorAddr] = builtin.StorageMarketActorAddr
-	addressToID[builtin.VerifiedRegistryActorAddr] = builtin.VerifiedRegistryActorAddr
-	addressToID[builtin.BurntFundsActorAddr] = builtin.BurntFundsActorAddr
-	initActor, err := p.node.StateGetActor(ctx, builtin.InitActorAddr, types.EmptyTSK)
+	addressToID[builtin2.SystemActorAddr] = builtin2.SystemActorAddr
+	addressToID[builtin2.InitActorAddr] = builtin2.InitActorAddr
+	addressToID[builtin2.RewardActorAddr] = builtin2.RewardActorAddr
+	addressToID[builtin2.CronActorAddr] = builtin2.CronActorAddr
+	addressToID[builtin2.StoragePowerActorAddr] = builtin2.StoragePowerActorAddr
+	addressToID[builtin2.StorageMarketActorAddr] = builtin2.StorageMarketActorAddr
+	addressToID[builtin2.VerifiedRegistryActorAddr] = builtin2.VerifiedRegistryActorAddr
+	addressToID[builtin2.BurntFundsActorAddr] = builtin2.BurntFundsActorAddr
+	initActor, err := p.node.StateGetActor(ctx, builtin2.InitActorAddr, types.EmptyTSK)
 	if err != nil {
 		return err
 	}
diff --git a/cmd/lotus-pcr/main.go b/cmd/lotus-pcr/main.go
index 4ce5bbb9f..769fc4bb2 100644
--- a/cmd/lotus-pcr/main.go
+++ b/cmd/lotus-pcr/main.go
@@ -14,7 +14,9 @@ import (
 	"strconv"
 	"time"
 
-	"github.com/filecoin-project/specs-actors/actors/builtin"
+	"github.com/filecoin-project/lotus/chain/actors/builtin"
+	builtin0 "github.com/filecoin-project/specs-actors/actors/builtin"
+
 	miner0 "github.com/filecoin-project/specs-actors/actors/builtin/miner"
 
 	"github.com/filecoin-project/go-state-types/network"
@@ -850,14 +852,14 @@ func (r *refunder) ProcessTipset(ctx context.Context, tipset *types.TipSet, refu
 			continue
 		}
 
-		if !a.IsStorageMinerActor() {
+		if !builtin.IsStorageMinerActor(a.Code) {
 			continue
 		}
 
 		var messageMethod string
 
 		switch m.Method {
-		case builtin.MethodsMiner.ProveCommitSector:
+		case builtin0.MethodsMiner.ProveCommitSector:
 			if !r.proveCommitEnabled {
 				continue
 			}
@@ -904,7 +906,7 @@ func (r *refunder) ProcessTipset(ctx context.Context, tipset *types.TipSet, refu
 			}
 
 			refundValue = collateral
-		case builtin.MethodsMiner.PreCommitSector:
+		case builtin0.MethodsMiner.PreCommitSector:
 			if !r.preCommitEnabled {
 				continue
 			}
diff --git a/cmd/lotus-shed/balances.go b/cmd/lotus-shed/balances.go
index 1c89a00cf..fba6d7724 100644
--- a/cmd/lotus-shed/balances.go
+++ b/cmd/lotus-shed/balances.go
@@ -6,7 +6,7 @@ import (
 	"strconv"
 
 	"github.com/docker/go-units"
-	lotusbuiltin "github.com/filecoin-project/lotus/chain/actors/builtin"
+	"github.com/filecoin-project/lotus/chain/actors/builtin"
 	"github.com/filecoin-project/lotus/chain/actors/builtin/power"
 	"github.com/filecoin-project/lotus/chain/actors/builtin/reward"
 
@@ -97,7 +97,7 @@ var chainBalanceCmd = &cli.Command{
 				Type:    string(act.Code.Hash()[2:]),
 			}
 
-			if act.IsStorageMinerActor() {
+			if builtin.IsStorageMinerActor(act.Code) {
 				pow, err := api.StateMinerPower(ctx, addr, tsk)
 				if err != nil {
 					return xerrors.Errorf("failed to get power: %w", err)
@@ -198,7 +198,7 @@ var chainBalanceStateCmd = &cli.Command{
 				PreCommits:    types.FIL(big.NewInt(0)),
 			}
 
-			if minerInfo && act.IsStorageMinerActor() {
+			if minerInfo && builtin.IsStorageMinerActor(act.Code) {
 				pow, _, _, err := stmgr.GetPowerRaw(ctx, sm, sroot, addr)
 				if err != nil {
 					return xerrors.Errorf("failed to get power: %w", err)
@@ -322,7 +322,7 @@ var chainPledgeCmd = &cli.Command{
 		}
 
 		var (
-			powerSmoothed    lotusbuiltin.FilterEstimate
+			powerSmoothed    builtin.FilterEstimate
 			pledgeCollateral abi.TokenAmount
 		)
 		if act, err := state.GetActor(power.Address); err != nil {
diff --git a/cmd/lotus-shed/genesis-verify.go b/cmd/lotus-shed/genesis-verify.go
index da2c82359..9a47d6561 100644
--- a/cmd/lotus-shed/genesis-verify.go
+++ b/cmd/lotus-shed/genesis-verify.go
@@ -6,6 +6,8 @@ import (
 	"os"
 	"sort"
 
+	"github.com/filecoin-project/lotus/chain/actors/builtin"
+
 	"github.com/fatih/color"
 	"github.com/ipfs/go-datastore"
 	cbor "github.com/ipfs/go-ipld-cbor"
@@ -95,14 +97,14 @@ var genesisVerifyCmd = &cli.Command{
 
 		if err := stree.ForEach(func(addr address.Address, act *types.Actor) error {
 			switch {
-			case act.IsStorageMinerActor():
+			case builtin.IsStorageMinerActor(act.Code):
 				_, err := miner.Load(store, act)
 				if err != nil {
 					return xerrors.Errorf("miner actor: %w", err)
 				}
 				// TODO: actually verify something here?
 				kminers[addr] = minerInfo{}
-			case act.IsMultisigActor():
+			case builtin.IsMultisigActor(act.Code):
 				st, err := multisig.Load(store, act)
 				if err != nil {
 					return xerrors.Errorf("multisig actor: %w", err)
@@ -123,7 +125,7 @@ var genesisVerifyCmd = &cli.Command{
 					Threshold: threshold,
 				}
 				msigAddrs = append(msigAddrs, addr)
-			case act.IsAccountActor():
+			case builtin.IsAccountActor(act.Code):
 				st, err := account.Load(store, act)
 				if err != nil {
 					// TODO: magik6k: this _used_ to log instead of failing, why?
diff --git a/cmd/lotus-shed/mempool-stats.go b/cmd/lotus-shed/mempool-stats.go
index 165c01432..d70cd4b71 100644
--- a/cmd/lotus-shed/mempool-stats.go
+++ b/cmd/lotus-shed/mempool-stats.go
@@ -18,6 +18,7 @@ import (
 
 	"github.com/filecoin-project/go-address"
 	lapi "github.com/filecoin-project/lotus/api"
+	"github.com/filecoin-project/lotus/chain/actors/builtin"
 	"github.com/filecoin-project/lotus/chain/types"
 	lcli "github.com/filecoin-project/lotus/cli"
 )
@@ -122,7 +123,7 @@ var mpoolStatsCmd = &cli.Command{
 				return false, err
 			}
 
-			ism := act.IsStorageMinerActor()
+			ism := builtin.IsStorageMinerActor(act.Code)
 			mcache[addr] = ism
 			return ism, nil
 		}
diff --git a/cmd/tvx/actor_mapping.go b/cmd/tvx/actor_mapping.go
deleted file mode 100644
index 8c306aca0..000000000
--- a/cmd/tvx/actor_mapping.go
+++ /dev/null
@@ -1,44 +0,0 @@
-package main
-
-import (
-	"reflect"
-
-	"github.com/filecoin-project/specs-actors/actors/builtin"
-	"github.com/ipfs/go-cid"
-	"github.com/multiformats/go-multihash"
-)
-
-var ActorMethodTable = make(map[string][]string, 64)
-
-var Actors = map[cid.Cid]interface{}{
-	builtin.InitActorCodeID:             builtin.MethodsInit,
-	builtin.CronActorCodeID:             builtin.MethodsCron,
-	builtin.AccountActorCodeID:          builtin.MethodsAccount,
-	builtin.StoragePowerActorCodeID:     builtin.MethodsPower,
-	builtin.StorageMinerActorCodeID:     builtin.MethodsMiner,
-	builtin.StorageMarketActorCodeID:    builtin.MethodsMarket,
-	builtin.PaymentChannelActorCodeID:   builtin.MethodsPaych,
-	builtin.MultisigActorCodeID:         builtin.MethodsMultisig,
-	builtin.RewardActorCodeID:           builtin.MethodsReward,
-	builtin.VerifiedRegistryActorCodeID: builtin.MethodsVerifiedRegistry,
-}
-
-func init() {
-	for code, methods := range Actors {
-		cmh, err := multihash.Decode(code.Hash()) // identity hash.
-		if err != nil {
-			panic(err)
-		}
-
-		var (
-			aname = string(cmh.Digest)
-			rt    = reflect.TypeOf(methods)
-			nf    = rt.NumField()
-		)
-
-		ActorMethodTable[aname] = append(ActorMethodTable[aname], "Send")
-		for i := 0; i < nf; i++ {
-			ActorMethodTable[aname] = append(ActorMethodTable[aname], rt.Field(i).Name)
-		}
-	}
-}
diff --git a/cmd/tvx/extract_many.go b/cmd/tvx/extract_many.go
index 9679a1dbd..fe0ce6a6c 100644
--- a/cmd/tvx/extract_many.go
+++ b/cmd/tvx/extract_many.go
@@ -12,10 +12,14 @@ import (
 	"strings"
 
 	"github.com/fatih/color"
+	"github.com/filecoin-project/go-state-types/abi"
 	"github.com/filecoin-project/go-state-types/exitcode"
 	"github.com/hashicorp/go-multierror"
+	"github.com/ipfs/go-cid"
+	"github.com/multiformats/go-multihash"
 	"github.com/urfave/cli/v2"
 
+	"github.com/filecoin-project/lotus/chain/stmgr"
 	lcli "github.com/filecoin-project/lotus/cli"
 )
 
@@ -118,6 +122,8 @@ func runExtractMany(c *cli.Context) error {
 		log.Println(color.GreenString("csv sanity check succeeded; header contains fields: %v", header))
 	}
 
+	codeCidBuilder := cid.V1Builder{Codec: cid.Raw, MhType: multihash.IDENTITY}
+
 	var (
 		generated []string
 		merr      = new(multierror.Error)
@@ -133,7 +139,7 @@ func runExtractMany(c *cli.Context) error {
 			return fmt.Errorf("failed to read row: %w", err)
 		}
 		var (
-			cid          = row[0]
+			mcid         = row[0]
 			actorcode    = row[1]
 			methodnumstr = row[2]
 			exitcodestr  = row[3]
@@ -155,13 +161,18 @@ func runExtractMany(c *cli.Context) error {
 			return fmt.Errorf("invalid method number: %s", methodnumstr)
 		}
 
+		codeCid, err := codeCidBuilder.Sum([]byte(actorcode))
+		if err != nil {
+			return fmt.Errorf("failed to compute actor code CID")
+		}
+
 		// Lookup the method in actor method table.
-		if m, ok := ActorMethodTable[actorcode]; !ok {
+		if m, ok := stmgr.MethodsMap[codeCid]; !ok {
 			return fmt.Errorf("unrecognized actor: %s", actorcode)
 		} else if methodnum >= len(m) {
 			return fmt.Errorf("unrecognized method number for actor %s: %d", actorcode, methodnum)
 		} else {
-			methodname = m[methodnum]
+			methodname = m[abi.MethodNum(methodnum)].Name
 		}
 
 		// exitcode string representations are of kind ErrType(0); strip out
@@ -181,14 +192,14 @@ func runExtractMany(c *cli.Context) error {
 			id:        id,
 			block:     block,
 			class:     "message",
-			cid:       cid,
+			cid:       mcid,
 			file:      file,
 			retain:    "accessed-cids",
 			precursor: PrecursorSelectSender,
 		}
 
 		if err := doExtract(ctx, fapi, opts); err != nil {
-			log.Println(color.RedString("failed to extract vector for message %s: %s; queuing for 'canonical' precursor selection", cid, err))
+			log.Println(color.RedString("failed to extract vector for message %s: %s; queuing for 'canonical' precursor selection", mcid, err))
 			retry = append(retry, opts)
 			continue
 		}
diff --git a/conformance/chaos/actor.go b/conformance/chaos/actor.go
index 477204374..d5e0b4352 100644
--- a/conformance/chaos/actor.go
+++ b/conformance/chaos/actor.go
@@ -3,7 +3,9 @@ package chaos
 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/filecoin-project/go-state-types/exitcode"
+	"github.com/filecoin-project/go-state-types/rt"
 	"github.com/filecoin-project/specs-actors/actors/builtin"
 	"github.com/filecoin-project/specs-actors/actors/runtime"
 	"github.com/ipfs/go-cid"
@@ -86,7 +88,11 @@ func (a Actor) Exports() []interface{} {
 	}
 }
 
-var _ runtime.Invokee = Actor{}
+func (a Actor) Code() cid.Cid     { return ChaosActorCodeCID }
+func (a Actor) State() cbor.Er    { return new(State) }
+func (a Actor) IsSingleton() bool { return true }
+
+var _ rt.VMActor = Actor{}
 
 // SendArgs are the arguments for the Send method.
 type SendArgs struct {
diff --git a/conformance/driver.go b/conformance/driver.go
index 9ced12d74..5648084ce 100644
--- a/conformance/driver.go
+++ b/conformance/driver.go
@@ -167,7 +167,7 @@ func (d *Driver) ExecuteMessage(bs blockstore.Blockstore, params ExecuteMessageP
 
 	// dummy state manager; only to reference the GetNetworkVersion method,
 	// which does not depend on state.
-	sm := new(stmgr.StateManager)
+	sm := stmgr.NewStateManager(nil)
 
 	vmOpts := &vm.VMOpts{
 		StateBase: params.Preroot,
@@ -187,11 +187,11 @@ func (d *Driver) ExecuteMessage(bs blockstore.Blockstore, params ExecuteMessageP
 		return nil, cid.Undef, err
 	}
 
-	invoker := vm.NewInvoker()
+	invoker := vm.NewActorRegistry()
 
 	// register the chaos actor if required by the vector.
 	if chaosOn, ok := d.selector["chaos_actor"]; ok && chaosOn == "true" {
-		invoker.Register(chaos.ChaosActorCodeCID, chaos.Actor{}, chaos.State{})
+		invoker.Register(nil, chaos.Actor{})
 	}
 
 	lvm.SetInvoker(invoker)
diff --git a/conformance/runner.go b/conformance/runner.go
index 2db53b3e4..626545b2b 100644
--- a/conformance/runner.go
+++ b/conformance/runner.go
@@ -233,7 +233,12 @@ func writeStateToTempCAR(bs blockstore.Blockstore, roots ...cid.Cid) (string, er
 			if link.Cid.Prefix().Codec == cid.FilCommitmentSealed || link.Cid.Prefix().Codec == cid.FilCommitmentUnsealed {
 				continue
 			}
-			out = append(out, link)
+			// ignore things we don't have, the state tree is incomplete.
+			if has, err := bs.Has(link.Cid); err != nil {
+				return nil, err
+			} else if has {
+				out = append(out, link)
+			}
 		}
 		return out, nil
 	}
diff --git a/documentation/en/api-methods.md b/documentation/en/api-methods.md
index d03bb94ed..1bae2c1e6 100644
--- a/documentation/en/api-methods.md
+++ b/documentation/en/api-methods.md
@@ -3863,7 +3863,7 @@ Inputs:
 ]
 ```
 
-Response: `3`
+Response: `4`
 
 ### StateReadState
 StateReadState returns the indicated actor's state.
diff --git a/extern/fil-blst b/extern/fil-blst
index 8609119cf..5f93488fc 160000
--- a/extern/fil-blst
+++ b/extern/fil-blst
@@ -1 +1 @@
-Subproject commit 8609119cf4595d1741139c24378fcd8bc4f1c475
+Subproject commit 5f93488fc0dbfb450f2355269f18fc67010d59bb
diff --git a/extern/filecoin-ffi b/extern/filecoin-ffi
index 57e38efe4..f640612a1 160000
--- a/extern/filecoin-ffi
+++ b/extern/filecoin-ffi
@@ -1 +1 @@
-Subproject commit 57e38efe4943f09d3127dcf6f0edd614e6acf68e
+Subproject commit f640612a1a1f7a2dd8b3a49e1531db0aa0f63447
diff --git a/extern/oni b/extern/oni
index 9a0d5cd73..dbee44e4f 160000
--- a/extern/oni
+++ b/extern/oni
@@ -1 +1 @@
-Subproject commit 9a0d5cd739de77b357589ac1fc8b756ed27299be
+Subproject commit dbee44e4f940a502971f17116ccbba61ceaf2674
diff --git a/extern/storage-sealing/checks.go b/extern/storage-sealing/checks.go
index 49994024f..1010d31b2 100644
--- a/extern/storage-sealing/checks.go
+++ b/extern/storage-sealing/checks.go
@@ -4,11 +4,9 @@ import (
 	"bytes"
 	"context"
 
+	"github.com/filecoin-project/lotus/chain/actors"
 	"github.com/filecoin-project/lotus/chain/actors/policy"
 
-	"github.com/filecoin-project/lotus/build"
-	miner0 "github.com/filecoin-project/specs-actors/actors/builtin/miner"
-
 	proof0 "github.com/filecoin-project/specs-actors/actors/runtime/proof"
 
 	"golang.org/x/xerrors"
@@ -102,16 +100,10 @@ func checkPrecommit(ctx context.Context, maddr address.Address, si SectorInfo, t
 		return &ErrApi{xerrors.Errorf("calling StateNetworkVersion: %w", err)}
 	}
 
-	var msd abi.ChainEpoch
-	if nv < build.ActorUpgradeNetworkVersion {
-		msd = miner0.MaxSealDuration[si.SectorType]
-	} else {
-		// TODO: ActorUpgrade(use MaxProveCommitDuration)
-		msd = 0
-	}
+	msd := policy.GetMaxProveCommitDuration(actors.VersionForNetwork(nv), si.SectorType)
 
-	if height-(si.TicketEpoch+SealRandomnessLookback) > msd {
-		return &ErrExpiredTicket{xerrors.Errorf("ticket expired: seal height: %d, head: %d", si.TicketEpoch+SealRandomnessLookback, height)}
+	if height-(si.TicketEpoch+policy.SealRandomnessLookback) > msd {
+		return &ErrExpiredTicket{xerrors.Errorf("ticket expired: seal height: %d, head: %d", si.TicketEpoch+policy.SealRandomnessLookback, height)}
 	}
 
 	pci, err := api.StateSectorPreCommitInfo(ctx, maddr, si.SectorNumber, tok)
diff --git a/extern/storage-sealing/constants.go b/extern/storage-sealing/constants.go
index 8c7fa5abc..d6aba1814 100644
--- a/extern/storage-sealing/constants.go
+++ b/extern/storage-sealing/constants.go
@@ -1,11 +1,4 @@
 package sealing
 
-import (
-	miner0 "github.com/filecoin-project/specs-actors/actors/builtin/miner"
-)
-
-// Epochs
-const SealRandomnessLookback = miner0.ChainFinality
-
 // Epochs
 const InteractivePoRepConfidence = 6
diff --git a/extern/storage-sealing/states_failed.go b/extern/storage-sealing/states_failed.go
index 88bf2d58d..d22830253 100644
--- a/extern/storage-sealing/states_failed.go
+++ b/extern/storage-sealing/states_failed.go
@@ -4,14 +4,14 @@ import (
 	"bytes"
 	"time"
 
-	"github.com/filecoin-project/lotus/chain/actors/builtin/miner"
-
 	"golang.org/x/xerrors"
 
+	"github.com/filecoin-project/lotus/chain/actors/builtin/market"
+	"github.com/filecoin-project/lotus/chain/actors/builtin/miner"
+
 	"github.com/filecoin-project/go-state-types/abi"
 	"github.com/filecoin-project/go-state-types/exitcode"
 	"github.com/filecoin-project/go-statemachine"
-	"github.com/filecoin-project/specs-actors/actors/builtin/market"
 
 	"github.com/filecoin-project/lotus/extern/sector-storage/zerocomm"
 )
diff --git a/extern/storage-sealing/states_sealing.go b/extern/storage-sealing/states_sealing.go
index a4e852454..96589bcd2 100644
--- a/extern/storage-sealing/states_sealing.go
+++ b/extern/storage-sealing/states_sealing.go
@@ -4,10 +4,9 @@ import (
 	"bytes"
 	"context"
 
-	"github.com/filecoin-project/lotus/build"
+	"github.com/filecoin-project/lotus/chain/actors"
 	"github.com/filecoin-project/lotus/chain/actors/builtin/miner"
 	"github.com/filecoin-project/lotus/chain/actors/policy"
-	miner0 "github.com/filecoin-project/specs-actors/actors/builtin/miner"
 
 	"golang.org/x/xerrors"
 
@@ -60,7 +59,7 @@ func (m *Sealing) getTicket(ctx statemachine.Context, sector SectorInfo) (abi.Se
 		return nil, 0, nil
 	}
 
-	ticketEpoch := epoch - SealRandomnessLookback
+	ticketEpoch := epoch - policy.SealRandomnessLookback
 	buf := new(bytes.Buffer)
 	if err := m.maddr.MarshalCBOR(buf); err != nil {
 		return nil, 0, err
@@ -189,13 +188,7 @@ func (m *Sealing) handlePreCommitting(ctx statemachine.Context, sector SectorInf
 		return ctx.Send(SectorSealPreCommit1Failed{xerrors.Errorf("failed to get network version: %w", err)})
 	}
 
-	var msd abi.ChainEpoch
-	if nv < build.ActorUpgradeNetworkVersion {
-		msd = miner0.MaxSealDuration[sector.SectorType]
-	} else {
-		// TODO: ActorUpgrade(use MaxProveCommitDuration)
-		msd = 0
-	}
+	msd := policy.GetMaxProveCommitDuration(actors.VersionForNetwork(nv), sector.SectorType)
 
 	if minExpiration := height + msd + miner.MinSectorExpiration + 10; expiration < minExpiration {
 		expiration = minExpiration
diff --git a/extern/storage-sealing/types.go b/extern/storage-sealing/types.go
index c044defd3..046271a7f 100644
--- a/extern/storage-sealing/types.go
+++ b/extern/storage-sealing/types.go
@@ -9,7 +9,7 @@ import (
 	"github.com/filecoin-project/go-state-types/abi"
 	"github.com/filecoin-project/go-state-types/big"
 	"github.com/filecoin-project/go-state-types/exitcode"
-	"github.com/filecoin-project/specs-actors/actors/builtin/miner"
+	miner0 "github.com/filecoin-project/specs-actors/actors/builtin/miner"
 	"github.com/filecoin-project/specs-storage/storage"
 
 	sectorstorage "github.com/filecoin-project/lotus/extern/sector-storage"
@@ -82,7 +82,7 @@ type SectorInfo struct {
 	CommR *cid.Cid
 	Proof []byte
 
-	PreCommitInfo    *miner.SectorPreCommitInfo
+	PreCommitInfo    *miner0.SectorPreCommitInfo
 	PreCommitDeposit big.Int
 	PreCommitMessage *cid.Cid
 	PreCommitTipSet  TipSetToken
diff --git a/go.mod b/go.mod
index 024a6a204..a160389b0 100644
--- a/go.mod
+++ b/go.mod
@@ -33,11 +33,12 @@ require (
 	github.com/filecoin-project/go-multistore v0.0.3
 	github.com/filecoin-project/go-padreader v0.0.0-20200903213702-ed5fae088b20
 	github.com/filecoin-project/go-paramfetch v0.0.2-0.20200701152213-3e0f0afdc261
-	github.com/filecoin-project/go-state-types v0.0.0-20200911004822-964d6c679cfc
+	github.com/filecoin-project/go-state-types v0.0.0-20200928172055-2df22083d8ab
 	github.com/filecoin-project/go-statemachine v0.0.0-20200925024713-05bd7c71fbfe
 	github.com/filecoin-project/go-statestore v0.1.0
 	github.com/filecoin-project/go-storedcounter v0.0.0-20200421200003-1c99c62e8a5b
-	github.com/filecoin-project/specs-actors v0.9.11
+	github.com/filecoin-project/specs-actors v0.9.12
+	github.com/filecoin-project/specs-actors/v2 v2.0.0-20201002200957-bdd876b3bbe9
 	github.com/filecoin-project/specs-storage v0.1.1-0.20200907031224-ed2e5cd13796
 	github.com/filecoin-project/test-vectors/schema v0.0.3
 	github.com/gbrlsnchs/jwt/v3 v3.0.0-beta.1
diff --git a/go.sum b/go.sum
index e820ede3a..5a00fff77 100644
--- a/go.sum
+++ b/go.sum
@@ -248,6 +248,8 @@ github.com/filecoin-project/go-hamt-ipld v0.1.5 h1:uoXrKbCQZ49OHpsTCkrThPNelC4W3
 github.com/filecoin-project/go-hamt-ipld v0.1.5 h1:uoXrKbCQZ49OHpsTCkrThPNelC4W3LPEk0OrS/ytIBM=
 github.com/filecoin-project/go-hamt-ipld v0.1.5/go.mod h1:6Is+ONR5Cd5R6XZoCse1CWaXZc0Hdb/JeX+EQCQzX24=
 github.com/filecoin-project/go-hamt-ipld v0.1.5/go.mod h1:6Is+ONR5Cd5R6XZoCse1CWaXZc0Hdb/JeX+EQCQzX24=
+github.com/filecoin-project/go-hamt-ipld/v2 v2.0.0 h1:b3UDemBYN2HNfk3KOXNuxgTTxlWi3xVvbQP0IT38fvM=
+github.com/filecoin-project/go-hamt-ipld/v2 v2.0.0/go.mod h1:7aWZdaQ1b16BVoQUYR+eEvrDCGJoPLxFpDynFjYfBjI=
 github.com/filecoin-project/go-jsonrpc v0.1.2-0.20200822201400-474f4fdccc52 h1:FXtCp0ybqdQL9knb3OGDpkNTaBbPxgkqPeWKotUwkH0=
 github.com/filecoin-project/go-jsonrpc v0.1.2-0.20200822201400-474f4fdccc52/go.mod h1:XBBpuKIMaXIIzeqzO1iucq4GvbF8CxmXRFoezRh+Cx4=
 github.com/filecoin-project/go-multistore v0.0.3 h1:vaRBY4YiA2UZFPK57RNuewypB8u0DzzQwqsL0XarpnI=
@@ -259,8 +261,8 @@ github.com/filecoin-project/go-paramfetch v0.0.2-0.20200701152213-3e0f0afdc261/g
 github.com/filecoin-project/go-state-types v0.0.0-20200903145444-247639ffa6ad/go.mod h1:IQ0MBPnonv35CJHtWSN3YY1Hz2gkPru1Q9qoaYLxx9I=
 github.com/filecoin-project/go-state-types v0.0.0-20200904021452-1883f36ca2f4/go.mod h1:IQ0MBPnonv35CJHtWSN3YY1Hz2gkPru1Q9qoaYLxx9I=
 github.com/filecoin-project/go-state-types v0.0.0-20200905071437-95828685f9df/go.mod h1:IQ0MBPnonv35CJHtWSN3YY1Hz2gkPru1Q9qoaYLxx9I=
-github.com/filecoin-project/go-state-types v0.0.0-20200911004822-964d6c679cfc h1:1vr/LoqGq5m5g37Q3sNSAjfwF1uJY0zmiHcvnxY6hik=
-github.com/filecoin-project/go-state-types v0.0.0-20200911004822-964d6c679cfc/go.mod h1:ezYnPf0bNkTsDibL/psSz5dy4B5awOJ/E7P2Saeep8g=
+github.com/filecoin-project/go-state-types v0.0.0-20200928172055-2df22083d8ab h1:cEDC5Ei8UuT99hPWhCjA72SM9AuRtnpvdSTIYbnzN8I=
+github.com/filecoin-project/go-state-types v0.0.0-20200928172055-2df22083d8ab/go.mod h1:ezYnPf0bNkTsDibL/psSz5dy4B5awOJ/E7P2Saeep8g=
 github.com/filecoin-project/go-statemachine v0.0.0-20200714194326-a77c3ae20989/go.mod h1:FGwQgZAt2Gh5mjlwJUlVB62JeYdo+if0xWxSEfBD9ig=
 github.com/filecoin-project/go-statemachine v0.0.0-20200925024713-05bd7c71fbfe h1:dF8u+LEWeIcTcfUcCf3WFVlc81Fr2JKg8zPzIbBDKDw=
 github.com/filecoin-project/go-statemachine v0.0.0-20200925024713-05bd7c71fbfe/go.mod h1:FGwQgZAt2Gh5mjlwJUlVB62JeYdo+if0xWxSEfBD9ig=
@@ -270,8 +272,10 @@ github.com/filecoin-project/go-storedcounter v0.0.0-20200421200003-1c99c62e8a5b
 github.com/filecoin-project/go-storedcounter v0.0.0-20200421200003-1c99c62e8a5b/go.mod h1:Q0GQOBtKf1oE10eSXSlhN45kDBdGvEcVOqMiffqX+N8=
 github.com/filecoin-project/specs-actors v0.9.4/go.mod h1:BStZQzx5x7TmCkLv0Bpa07U6cPKol6fd3w9KjMPZ6Z4=
 github.com/filecoin-project/specs-actors v0.9.7/go.mod h1:wM2z+kwqYgXn5Z7scV1YHLyd1Q1cy0R8HfTIWQ0BFGU=
-github.com/filecoin-project/specs-actors v0.9.11 h1:TnpG7HAeiUrfj0mJM7UaPW0P2137H62RGof7ftT5Mas=
-github.com/filecoin-project/specs-actors v0.9.11/go.mod h1:czlvLQGEX0fjLLfdNHD7xLymy6L3n7aQzRWzsYGf+ys=
+github.com/filecoin-project/specs-actors v0.9.12 h1:iIvk58tuMtmloFNHhAOQHG+4Gci6Lui0n7DYQGi3cJk=
+github.com/filecoin-project/specs-actors v0.9.12/go.mod h1:TS1AW/7LbG+615j4NsjMK1qlpAwaFsG9w0V2tg2gSao=
+github.com/filecoin-project/specs-actors/v2 v2.0.0-20201002200957-bdd876b3bbe9 h1:UXVcGwUD9GJYNcgfGbf7ok790wrunvUhl5ZlgApGhGs=
+github.com/filecoin-project/specs-actors/v2 v2.0.0-20201002200957-bdd876b3bbe9/go.mod h1:52FuQUNDXq2WDg+6+UOhkqBuNc2e62h9BCIB67Bluxg=
 github.com/filecoin-project/specs-storage v0.1.1-0.20200907031224-ed2e5cd13796 h1:dJsTPWpG2pcTeojO2pyn0c6l+x/3MZYCBgo/9d11JEk=
 github.com/filecoin-project/specs-storage v0.1.1-0.20200907031224-ed2e5cd13796/go.mod h1:nJRRM7Aa9XVvygr3W9k6xGF46RWzr2zxF/iGoAIfA/g=
 github.com/filecoin-project/test-vectors/schema v0.0.3 h1:1zuBo25B3016inbygYLgYFdpJ2m1BDTbAOCgABRleiU=
@@ -1396,6 +1400,7 @@ github.com/whyrusleeping/cbor-gen v0.0.0-20200414195334-429a0b5e922e/go.mod h1:X
 github.com/whyrusleeping/cbor-gen v0.0.0-20200504204219-64967432584d/go.mod h1:W5MvapuoHRP8rz4vxjwCK1pDqF1aQcWsV5PZ+AHbqdg=
 github.com/whyrusleeping/cbor-gen v0.0.0-20200710004633-5379fc63235d/go.mod h1:fgkXqYy7bV2cFeIEOkVTZS/WjXARfBqSH6Q2qHL33hQ=
 github.com/whyrusleeping/cbor-gen v0.0.0-20200715143311-227fab5a2377/go.mod h1:fgkXqYy7bV2cFeIEOkVTZS/WjXARfBqSH6Q2qHL33hQ=
+github.com/whyrusleeping/cbor-gen v0.0.0-20200806213330-63aa96ca5488/go.mod h1:fgkXqYy7bV2cFeIEOkVTZS/WjXARfBqSH6Q2qHL33hQ=
 github.com/whyrusleeping/cbor-gen v0.0.0-20200810223238-211df3b9e24c/go.mod h1:fgkXqYy7bV2cFeIEOkVTZS/WjXARfBqSH6Q2qHL33hQ=
 github.com/whyrusleeping/cbor-gen v0.0.0-20200812213548-958ddffe352c/go.mod h1:fgkXqYy7bV2cFeIEOkVTZS/WjXARfBqSH6Q2qHL33hQ=
 github.com/whyrusleeping/cbor-gen v0.0.0-20200826160007-0b9f6c5fb163 h1:TtcUeY2XZSriVWR1pXyfCBWIf/NGC2iUdNw1lofUjUU=
diff --git a/journal/registry_test.go b/journal/registry_test.go
index 9d2085c12..bce3d3f17 100644
--- a/journal/registry_test.go
+++ b/journal/registry_test.go
@@ -14,7 +14,7 @@ func TestDisabledEvents(t *testing.T) {
 			registry := NewEventTypeRegistry(dis)
 
 			reg1 := registry.RegisterEventType("system1", "disabled1")
-			reg2 := registry.RegisterEventType("system2", "disabled2")
+			reg2 := registry.RegisterEventType("system1", "disabled2")
 
 			req.False(reg1.Enabled())
 			req.False(reg2.Enabled())
@@ -29,21 +29,21 @@ func TestDisabledEvents(t *testing.T) {
 
 	t.Run("direct", test(DisabledEvents{
 		EventType{System: "system1", Event: "disabled1"},
-		EventType{System: "system2", Event: "disabled2"},
+		EventType{System: "system1", Event: "disabled2"},
 	}))
 
-	dis, err := ParseDisabledEvents("system1:disabled1,system2:disabled2")
+	dis, err := ParseDisabledEvents("system1:disabled1,system1:disabled2")
 	req.NoError(err)
 
 	t.Run("parsed", test(dis))
 
-	dis, err = ParseDisabledEvents("  system1:disabled1 , system2:disabled2  ")
+	dis, err = ParseDisabledEvents("  system1:disabled1 , system1:disabled2  ")
 	req.NoError(err)
 
 	t.Run("parsed_spaces", test(dis))
 }
 
 func TestParseDisableEvents(t *testing.T) {
-	_, err := ParseDisabledEvents("system1:disabled1:failed,system2:disabled2")
+	_, err := ParseDisabledEvents("system1:disabled1:failed,system1:disabled2")
 	require.Error(t, err)
 }
diff --git a/journal/types.go b/journal/types.go
index 56c7d4bc0..5b51ed4c8 100644
--- a/journal/types.go
+++ b/journal/types.go
@@ -22,7 +22,7 @@ var (
 // DisabledEvents is the set of event types whose journaling is suppressed.
 type DisabledEvents []EventType
 
-// ParseDisabledEvents parses a string of the form: "system1:event1,system2:event2[,...]"
+// ParseDisabledEvents parses a string of the form: "system1:event1,system1:event2[,...]"
 // into a DisabledEvents object, returning an error if the string failed to parse.
 //
 // It sanitizes strings via strings.TrimSpace.
diff --git a/lotuspond/front/src/chain/methodgen.go b/lotuspond/front/src/chain/methodgen.go
index 3197803fe..5a00d5e6e 100644
--- a/lotuspond/front/src/chain/methodgen.go
+++ b/lotuspond/front/src/chain/methodgen.go
@@ -4,12 +4,11 @@ import (
 	"encoding/json"
 	"io/ioutil"
 	"os"
-	"reflect"
 
-	"github.com/ipfs/go-cid"
 	"github.com/multiformats/go-multihash"
 
-	"github.com/filecoin-project/specs-actors/actors/builtin"
+	"github.com/filecoin-project/go-state-types/abi"
+	"github.com/filecoin-project/lotus/chain/stmgr"
 )
 
 func main() {
@@ -17,6 +16,7 @@ func main() {
 		panic(err) // note: must run in lotuspond/front/src/chain
 	}
 
+	// TODO: ActorUpgrade: this is going to be a problem.
 	names := map[string]string{
 		"system":   "fil/1/system",
 		"init":     "fil/1/init",
@@ -42,33 +42,25 @@ func main() {
 		}
 	}
 
-	methods := map[cid.Cid]interface{}{
-		// builtin.SystemActorCodeID:        builtin.MethodsSystem - apparently it doesn't have methods
-		builtin.InitActorCodeID:             builtin.MethodsInit,
-		builtin.CronActorCodeID:             builtin.MethodsCron,
-		builtin.AccountActorCodeID:          builtin.MethodsAccount,
-		builtin.StoragePowerActorCodeID:     builtin.MethodsPower,
-		builtin.StorageMinerActorCodeID:     builtin.MethodsMiner,
-		builtin.StorageMarketActorCodeID:    builtin.MethodsMarket,
-		builtin.PaymentChannelActorCodeID:   builtin.MethodsPaych,
-		builtin.MultisigActorCodeID:         builtin.MethodsMultisig,
-		builtin.RewardActorCodeID:           builtin.MethodsReward,
-		builtin.VerifiedRegistryActorCodeID: builtin.MethodsVerifiedRegistry,
-	}
-
 	out := map[string][]string{}
-	for c, methods := range methods {
+
+	for c, methods := range stmgr.MethodsMap {
 		cmh, err := multihash.Decode(c.Hash())
 		if err != nil {
 			panic(err)
 		}
 
-		rt := reflect.TypeOf(methods)
-		nf := rt.NumField()
+		name := string(cmh.Digest)
+		remaining := len(methods)
 
-		out[string(cmh.Digest)] = append(out[string(cmh.Digest)], "Send")
-		for i := 0; i < nf; i++ {
-			out[string(cmh.Digest)] = append(out[string(cmh.Digest)], rt.Field(i).Name)
+		// iterate over actor methods in order.
+		for i := abi.MethodNum(0); remaining > 0; i++ {
+			m, ok := methods[i]
+			if !ok {
+				continue
+			}
+			out[name] = append(out[name], m.Name)
+			remaining--
 		}
 	}
 
diff --git a/lotuspond/front/src/chain/methods.json b/lotuspond/front/src/chain/methods.json
index ce4919cc4..5e15b053b 100644
--- a/lotuspond/front/src/chain/methods.json
+++ b/lotuspond/front/src/chain/methods.json
@@ -87,6 +87,10 @@
     "SubmitPoRepForBulkVerify",
     "CurrentTotalPower"
   ],
+  "fil/1/system": [
+    "Send",
+    "Constructor"
+  ],
   "fil/1/verifiedregistry": [
     "Send",
     "Constructor",
@@ -95,5 +99,107 @@
     "AddVerifiedClient",
     "UseBytes",
     "RestoreBytes"
+  ],
+  "fil/2/account": [
+    "Send",
+    "Constructor",
+    "PubkeyAddress"
+  ],
+  "fil/2/cron": [
+    "Send",
+    "Constructor",
+    "EpochTick"
+  ],
+  "fil/2/init": [
+    "Send",
+    "Constructor",
+    "Exec"
+  ],
+  "fil/2/multisig": [
+    "Send",
+    "Constructor",
+    "Propose",
+    "Approve",
+    "Cancel",
+    "AddSigner",
+    "RemoveSigner",
+    "SwapSigner",
+    "ChangeNumApprovalsThreshold",
+    "LockBalance"
+  ],
+  "fil/2/paymentchannel": [
+    "Send",
+    "Constructor",
+    "UpdateChannelState",
+    "Settle",
+    "Collect"
+  ],
+  "fil/2/reward": [
+    "Send",
+    "Constructor",
+    "AwardBlockReward",
+    "ThisEpochReward",
+    "UpdateNetworkKPI"
+  ],
+  "fil/2/storagemarket": [
+    "Send",
+    "Constructor",
+    "AddBalance",
+    "WithdrawBalance",
+    "PublishStorageDeals",
+    "VerifyDealsForActivation",
+    "ActivateDeals",
+    "OnMinerSectorsTerminate",
+    "ComputeDataCommitment",
+    "CronTick"
+  ],
+  "fil/2/storageminer": [
+    "Send",
+    "Constructor",
+    "ControlAddresses",
+    "ChangeWorkerAddress",
+    "ChangePeerID",
+    "SubmitWindowedPoSt",
+    "PreCommitSector",
+    "ProveCommitSector",
+    "ExtendSectorExpiration",
+    "TerminateSectors",
+    "DeclareFaults",
+    "DeclareFaultsRecovered",
+    "OnDeferredCronEvent",
+    "CheckSectorProven",
+    "ApplyRewards",
+    "ReportConsensusFault",
+    "WithdrawBalance",
+    "ConfirmSectorProofsValid",
+    "ChangeMultiaddrs",
+    "CompactPartitions",
+    "CompactSectorNumbers",
+    "ConfirmUpdateWorkerKey",
+    "RepayDebt"
+  ],
+  "fil/2/storagepower": [
+    "Send",
+    "Constructor",
+    "CreateMiner",
+    "UpdateClaimedPower",
+    "EnrollCronEvent",
+    "OnEpochTickEnd",
+    "UpdatePledgeTotal",
+    "SubmitPoRepForBulkVerify",
+    "CurrentTotalPower"
+  ],
+  "fil/2/system": [
+    "Send",
+    "Constructor"
+  ],
+  "fil/2/verifiedregistry": [
+    "Send",
+    "Constructor",
+    "AddVerifier",
+    "RemoveVerifier",
+    "AddVerifiedClient",
+    "UseBytes",
+    "RestoreBytes"
   ]
 }
\ No newline at end of file
diff --git a/markets/retrievaladapter/client.go b/markets/retrievaladapter/client.go
index ab81dd8c9..1bef23e12 100644
--- a/markets/retrievaladapter/client.go
+++ b/markets/retrievaladapter/client.go
@@ -3,8 +3,6 @@ package retrievaladapter
 import (
 	"context"
 
-	"github.com/filecoin-project/specs-actors/actors/builtin/paych"
-
 	"github.com/filecoin-project/go-address"
 	"github.com/filecoin-project/go-fil-markets/retrievalmarket"
 	"github.com/filecoin-project/go-fil-markets/shared"
@@ -12,6 +10,7 @@ import (
 	"github.com/ipfs/go-cid"
 	"github.com/multiformats/go-multiaddr"
 
+	"github.com/filecoin-project/lotus/chain/actors/builtin/paych"
 	"github.com/filecoin-project/lotus/chain/types"
 	"github.com/filecoin-project/lotus/node/impl/full"
 	payapi "github.com/filecoin-project/lotus/node/impl/paych"
diff --git a/markets/retrievaladapter/provider.go b/markets/retrievaladapter/provider.go
index 443c4fb4a..674ec4793 100644
--- a/markets/retrievaladapter/provider.go
+++ b/markets/retrievaladapter/provider.go
@@ -5,6 +5,7 @@ import (
 	"io"
 
 	"github.com/filecoin-project/lotus/api"
+	"github.com/filecoin-project/lotus/chain/actors/builtin/paych"
 	"github.com/filecoin-project/lotus/chain/types"
 	sectorstorage "github.com/filecoin-project/lotus/extern/sector-storage"
 	"github.com/filecoin-project/lotus/extern/sector-storage/storiface"
@@ -14,7 +15,6 @@ import (
 	"github.com/filecoin-project/go-fil-markets/retrievalmarket"
 	"github.com/filecoin-project/go-fil-markets/shared"
 	"github.com/filecoin-project/go-state-types/abi"
-	"github.com/filecoin-project/specs-actors/actors/builtin/paych"
 
 	"github.com/ipfs/go-cid"
 )
diff --git a/node/builder.go b/node/builder.go
index 41fb01ef7..0d48ec130 100644
--- a/node/builder.go
+++ b/node/builder.go
@@ -259,7 +259,8 @@ func Online() Option {
 			Override(new(ffiwrapper.Verifier), ffiwrapper.ProofVerifier),
 			Override(new(vm.SyscallBuilder), vm.Syscalls),
 			Override(new(*store.ChainStore), modules.ChainStore),
-			Override(new(*stmgr.StateManager), stmgr.NewStateManager),
+			Override(new(stmgr.UpgradeSchedule), stmgr.DefaultUpgradeSchedule()),
+			Override(new(*stmgr.StateManager), stmgr.NewStateManagerWithUpgradeSchedule),
 			Override(new(*wallet.Wallet), wallet.NewWallet),
 			Override(new(*messagesigner.MessageSigner), messagesigner.NewMessageSigner),
 
diff --git a/node/impl/client/client.go b/node/impl/client/client.go
index 5c1752154..f146dcea3 100644
--- a/node/impl/client/client.go
+++ b/node/impl/client/client.go
@@ -42,7 +42,6 @@ import (
 	"github.com/filecoin-project/go-multistore"
 	"github.com/filecoin-project/go-padreader"
 	"github.com/filecoin-project/go-state-types/abi"
-	miner0 "github.com/filecoin-project/specs-actors/actors/builtin/miner"
 
 	"github.com/filecoin-project/lotus/extern/sector-storage/ffiwrapper"
 	marketevents "github.com/filecoin-project/lotus/markets/loggers"
@@ -88,7 +87,7 @@ func calcDealExpiration(minDuration uint64, md *dline.Info, startEpoch abi.Chain
 	minExp := startEpoch + abi.ChainEpoch(minDuration)
 
 	// Align on miners ProvingPeriodBoundary
-	return minExp + miner0.WPoStProvingPeriod - (minExp % miner0.WPoStProvingPeriod) + (md.PeriodStart % miner0.WPoStProvingPeriod) - 1
+	return minExp + md.WPoStProvingPeriod - (minExp % md.WPoStProvingPeriod) + (md.PeriodStart % md.WPoStProvingPeriod) - 1
 }
 
 func (a *API) imgr() *importmgr.Mgr {
diff --git a/node/impl/full/chain.go b/node/impl/full/chain.go
index 9606a023a..095e32ad2 100644
--- a/node/impl/full/chain.go
+++ b/node/impl/full/chain.go
@@ -285,6 +285,8 @@ func (s stringKey) Key() string {
 	return (string)(s)
 }
 
+// TODO: ActorUpgrade: this entire function is a problem (in theory) as we don't know the HAMT version.
+// In practice, hamt v0 should work "just fine" for reading.
 func resolveOnce(bs blockstore.Blockstore) func(ctx context.Context, ds ipld.NodeGetter, nd ipld.Node, names []string) (*ipld.Link, []string, error) {
 	return func(ctx context.Context, ds ipld.NodeGetter, nd ipld.Node, names []string) (*ipld.Link, []string, error) {
 		store := adt.WrapStore(ctx, cbor.NewCborStore(bs))
@@ -422,7 +424,7 @@ func resolveOnce(bs blockstore.Blockstore) func(ctx context.Context, ds ipld.Nod
 				return nil, nil, xerrors.Errorf("getting actor head for @state: %w", err)
 			}
 
-			m, err := vm.DumpActorState(act.Code, head.RawData())
+			m, err := vm.DumpActorState(&act, head.RawData())
 			if err != nil {
 				return nil, nil, err
 			}
diff --git a/node/impl/full/gas.go b/node/impl/full/gas.go
index f03807c80..c912c7a8c 100644
--- a/node/impl/full/gas.go
+++ b/node/impl/full/gas.go
@@ -6,6 +6,8 @@ import (
 	"math/rand"
 	"sort"
 
+	"github.com/filecoin-project/lotus/chain/actors/builtin"
+
 	"go.uber.org/fx"
 	"golang.org/x/xerrors"
 
@@ -182,7 +184,7 @@ func (a *GasAPI) GasEstimateGasLimit(ctx context.Context, msgIn *types.Message,
 		return res.MsgRct.GasUsed, nil
 	}
 
-	if !act.IsPaymentChannelActor() {
+	if !builtin.IsPaymentChannelActor(act.Code) {
 		return res.MsgRct.GasUsed, nil
 	}
 	if msgIn.Method != builtin0.MethodsPaych.Collect {
diff --git a/node/impl/full/multisig.go b/node/impl/full/multisig.go
index 8c15a27be..715689edc 100644
--- a/node/impl/full/multisig.go
+++ b/node/impl/full/multisig.go
@@ -9,15 +9,13 @@ import (
 	"github.com/filecoin-project/go-state-types/abi"
 	"github.com/filecoin-project/lotus/api"
 	"github.com/filecoin-project/lotus/chain/actors"
-	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/types"
 
 	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/ipfs/go-cid"
-	"github.com/minio/blake2b-simd"
 	"go.uber.org/fx"
 	"golang.org/x/xerrors"
 )
@@ -30,58 +28,31 @@ type MsigAPI struct {
 	MpoolAPI  MpoolAPI
 }
 
+func (a *MsigAPI) messageBuilder(ctx context.Context, from address.Address) (multisig.MessageBuilder, error) {
+	nver, err := a.StateAPI.StateNetworkVersion(ctx, types.EmptyTSK)
+	if err != nil {
+		return nil, err
+	}
+
+	return multisig.Message(actors.VersionForNetwork(nver), from), nil
+}
+
 // TODO: remove gp (gasPrice) from arguments
+// TODO: Add "vesting start" to arguments.
 func (a *MsigAPI) MsigCreate(ctx context.Context, req uint64, addrs []address.Address, duration abi.ChainEpoch, val types.BigInt, src address.Address, gp types.BigInt) (cid.Cid, error) {
 
-	lenAddrs := uint64(len(addrs))
-
-	if lenAddrs < req {
-		return cid.Undef, xerrors.Errorf("cannot require signing of more addresses than provided for multisig")
+	mb, err := a.messageBuilder(ctx, src)
+	if err != nil {
+		return cid.Undef, err
 	}
 
-	if req == 0 {
-		req = lenAddrs
-	}
-
-	if src == address.Undef {
-		return cid.Undef, xerrors.Errorf("must provide source address")
-	}
-
-	// Set up constructor parameters for multisig
-	msigParams := &multisig0.ConstructorParams{
-		Signers:               addrs,
-		NumApprovalsThreshold: req,
-		UnlockDuration:        duration,
-	}
-
-	enc, actErr := actors.SerializeParams(msigParams)
-	if actErr != nil {
-		return cid.Undef, actErr
-	}
-
-	// new actors are created by invoking 'exec' on the init actor with the constructor params
-	// TODO: network upgrade?
-	execParams := &init0.ExecParams{
-		CodeCID:           builtin0.MultisigActorCodeID,
-		ConstructorParams: enc,
-	}
-
-	enc, actErr = actors.SerializeParams(execParams)
-	if actErr != nil {
-		return cid.Undef, actErr
-	}
-
-	// now we create the message to send this with
-	msg := types.Message{
-		To:     init_.Address,
-		From:   src,
-		Method: builtin0.MethodsInit.Exec,
-		Params: enc,
-		Value:  val,
+	msg, err := mb.Create(addrs, req, 0, duration, val)
+	if err != nil {
+		return cid.Undef, err
 	}
 
 	// send the message out to the network
-	smsg, err := a.MpoolAPI.MpoolPushMessage(ctx, &msg, nil)
+	smsg, err := a.MpoolAPI.MpoolPushMessage(ctx, msg, nil)
 	if err != nil {
 		return cid.Undef, err
 	}
@@ -91,38 +62,14 @@ func (a *MsigAPI) MsigCreate(ctx context.Context, req uint64, addrs []address.Ad
 
 func (a *MsigAPI) MsigPropose(ctx context.Context, msig address.Address, to address.Address, amt types.BigInt, src address.Address, method uint64, params []byte) (cid.Cid, error) {
 
-	if msig == address.Undef {
-		return cid.Undef, xerrors.Errorf("must provide a multisig address for proposal")
+	mb, err := a.messageBuilder(ctx, src)
+	if err != nil {
+		return cid.Undef, err
 	}
 
-	if to == address.Undef {
-		return cid.Undef, xerrors.Errorf("must provide a target address for proposal")
-	}
-
-	if amt.Sign() == -1 {
-		return cid.Undef, xerrors.Errorf("must provide a positive amount for proposed send")
-	}
-
-	if src == address.Undef {
-		return cid.Undef, xerrors.Errorf("must provide source address")
-	}
-
-	enc, actErr := actors.SerializeParams(&multisig0.ProposeParams{
-		To:     to,
-		Value:  amt,
-		Method: abi.MethodNum(method),
-		Params: params,
-	})
-	if actErr != nil {
-		return cid.Undef, xerrors.Errorf("failed to serialize parameters: %w", actErr)
-	}
-
-	msg := &types.Message{
-		To:     msig,
-		From:   src,
-		Value:  types.NewInt(0),
-		Method: builtin0.MethodsMultisig.Propose,
-		Params: enc,
+	msg, err := mb.Propose(msig, to, amt, abi.MethodNum(method), params)
+	if err != nil {
+		return cid.Undef, xerrors.Errorf("failed to create proposal: %w", err)
 	}
 
 	smsg, err := a.MpoolAPI.MpoolPushMessage(ctx, msg, nil)
@@ -200,14 +147,6 @@ func (a *MsigAPI) msigApproveOrCancel(ctx context.Context, operation api.MsigPro
 		return cid.Undef, xerrors.Errorf("must provide multisig address")
 	}
 
-	if to == address.Undef {
-		return cid.Undef, xerrors.Errorf("must provide proposed target address")
-	}
-
-	if amt.Sign() == -1 {
-		return cid.Undef, xerrors.Errorf("must provide the positive amount that was proposed")
-	}
-
 	if src == address.Undef {
 		return cid.Undef, xerrors.Errorf("must provide source address")
 	}
@@ -220,7 +159,7 @@ func (a *MsigAPI) msigApproveOrCancel(ctx context.Context, operation api.MsigPro
 		proposer = proposerID
 	}
 
-	p := multisig0.ProposalHashData{
+	p := multisig.ProposalHashData{
 		Requester: proposer,
 		To:        to,
 		Value:     amt,
@@ -228,42 +167,22 @@ func (a *MsigAPI) msigApproveOrCancel(ctx context.Context, operation api.MsigPro
 		Params:    params,
 	}
 
-	pser, err := p.Serialize()
-	if err != nil {
-		return cid.Undef, err
-	}
-	phash := blake2b.Sum256(pser)
-
-	enc, err := actors.SerializeParams(&multisig0.TxnIDParams{
-		ID:           multisig0.TxnID(txID),
-		ProposalHash: phash[:],
-	})
-
+	mb, err := a.messageBuilder(ctx, src)
 	if err != nil {
 		return cid.Undef, err
 	}
 
-	var msigResponseMethod abi.MethodNum
-
-	/*
-		We pass in a MsigProposeResponse instead of MethodNum to
-		tighten the possible inputs to just Approve and Cancel.
-	*/
+	var msg *types.Message
 	switch operation {
 	case api.MsigApprove:
-		msigResponseMethod = builtin0.MethodsMultisig.Approve
+		msg, err = mb.Approve(msig, txID, &p)
 	case api.MsigCancel:
-		msigResponseMethod = builtin0.MethodsMultisig.Cancel
+		msg, err = mb.Cancel(msig, txID, &p)
 	default:
 		return cid.Undef, xerrors.Errorf("Invalid operation for msigApproveOrCancel")
 	}
-
-	msg := &types.Message{
-		To:     msig,
-		From:   src,
-		Value:  types.NewInt(0),
-		Method: msigResponseMethod,
-		Params: enc,
+	if err != nil {
+		return cid.Undef, err
 	}
 
 	smsg, err := a.MpoolAPI.MpoolPushMessage(ctx, msg, nil)
diff --git a/node/impl/full/state.go b/node/impl/full/state.go
index e5bd9f9d8..3a4390d03 100644
--- a/node/impl/full/state.go
+++ b/node/impl/full/state.go
@@ -5,10 +5,8 @@ import (
 	"context"
 	"strconv"
 
-	lotusbuiltin "github.com/filecoin-project/lotus/chain/actors/builtin"
-
-	builtin0 "github.com/filecoin-project/specs-actors/actors/builtin"
-	market0 "github.com/filecoin-project/specs-actors/actors/builtin/market"
+	"github.com/filecoin-project/lotus/chain/actors/builtin"
+	"github.com/filecoin-project/lotus/chain/actors/policy"
 
 	"github.com/filecoin-project/lotus/chain/actors/builtin/verifreg"
 
@@ -411,7 +409,7 @@ func (a *StateAPI) StateReadState(ctx context.Context, actor address.Address, ts
 		return nil, xerrors.Errorf("getting actor head: %w", err)
 	}
 
-	oif, err := vm.DumpActorState(act.Code, blk.RawData())
+	oif, err := vm.DumpActorState(act, blk.RawData())
 	if err != nil {
 		return nil, xerrors.Errorf("dumping actor state (a:%s): %w", actor, err)
 	}
@@ -883,10 +881,10 @@ func (a *StateAPI) StateMinerPreCommitDepositForPower(ctx context.Context, maddr
 	} else {
 		// NB: not exactly accurate, but should always lead us to *over* estimate, not under
 		duration := pci.Expiration - ts.Height()
-		sectorWeight = lotusbuiltin.QAPowerForWeight(ssize, duration, w, vw)
+		sectorWeight = builtin.QAPowerForWeight(ssize, duration, w, vw)
 	}
 
-	var powerSmoothed lotusbuiltin.FilterEstimate
+	var powerSmoothed builtin.FilterEstimate
 	if act, err := state.GetActor(power.Address); err != nil {
 		return types.EmptyInt, xerrors.Errorf("loading power actor: %w", err)
 	} else if s, err := power.Load(store, act); err != nil {
@@ -944,11 +942,11 @@ func (a *StateAPI) StateMinerInitialPledgeCollateral(ctx context.Context, maddr
 	} else {
 		// NB: not exactly accurate, but should always lead us to *over* estimate, not under
 		duration := pci.Expiration - ts.Height()
-		sectorWeight = lotusbuiltin.QAPowerForWeight(ssize, duration, w, vw)
+		sectorWeight = builtin.QAPowerForWeight(ssize, duration, w, vw)
 	}
 
 	var (
-		powerSmoothed    lotusbuiltin.FilterEstimate
+		powerSmoothed    builtin.FilterEstimate
 		pledgeCollateral abi.TokenAmount
 	)
 	if act, err := state.GetActor(power.Address); err != nil {
@@ -1108,12 +1106,12 @@ func (a *StateAPI) StateDealProviderCollateralBounds(ctx context.Context, size a
 		return api.DealCollateralBounds{}, xerrors.Errorf("loading tipset %s: %w", tsk, err)
 	}
 
-	pact, err := a.StateGetActor(ctx, builtin0.StoragePowerActorAddr, tsk)
+	pact, err := a.StateGetActor(ctx, power.Address, tsk)
 	if err != nil {
 		return api.DealCollateralBounds{}, xerrors.Errorf("failed to load power actor: %w", err)
 	}
 
-	ract, err := a.StateGetActor(ctx, builtin0.RewardActorAddr, tsk)
+	ract, err := a.StateGetActor(ctx, reward.Address, tsk)
 	if err != nil {
 		return api.DealCollateralBounds{}, xerrors.Errorf("failed to load reward actor: %w", err)
 	}
@@ -1143,7 +1141,7 @@ func (a *StateAPI) StateDealProviderCollateralBounds(ctx context.Context, size a
 		return api.DealCollateralBounds{}, xerrors.Errorf("getting reward baseline power: %w", err)
 	}
 
-	min, max := market0.DealProviderCollateralBounds(size,
+	min, max := policy.DealProviderCollateralBounds(size,
 		verified,
 		powClaim.RawBytePower,
 		powClaim.QualityAdjPower,
diff --git a/node/test/builder.go b/node/test/builder.go
index c496b1e4c..a3455f376 100644
--- a/node/test/builder.go
+++ b/node/test/builder.go
@@ -137,7 +137,7 @@ func CreateTestStorageNode(ctx context.Context, t *testing.T, waddr address.Addr
 	return test.TestStorageNode{StorageMiner: minerapi, MineOne: mineOne}
 }
 
-func Builder(t *testing.T, nFull int, storage []test.StorageMiner) ([]test.TestNode, []test.TestStorageNode) {
+func Builder(t *testing.T, nFull int, storage []test.StorageMiner, opts ...node.Option) ([]test.TestNode, []test.TestStorageNode) {
 	ctx := context.Background()
 	mn := mocknet.New(ctx)
 
@@ -198,6 +198,7 @@ func Builder(t *testing.T, nFull int, storage []test.StorageMiner) ([]test.TestN
 	templ := &genesis.Template{
 		Accounts:         genaccs,
 		Miners:           genms,
+		NetworkName:      "test",
 		Timestamp:        uint64(time.Now().Unix() - 10000), // some time sufficiently far in the past
 		VerifregRootKey:  gen.DefaultVerifregRootkeyActor,
 		RemainderAccount: gen.DefaultRemainderAccountActor,
@@ -223,6 +224,7 @@ func Builder(t *testing.T, nFull int, storage []test.StorageMiner) ([]test.TestN
 			node.Test(),
 
 			genesis,
+			node.Options(opts...),
 		)
 		if err != nil {
 			t.Fatal(err)
@@ -284,7 +286,7 @@ func Builder(t *testing.T, nFull int, storage []test.StorageMiner) ([]test.TestN
 	return fulls, storers
 }
 
-func MockSbBuilder(t *testing.T, nFull int, storage []test.StorageMiner) ([]test.TestNode, []test.TestStorageNode) {
+func MockSbBuilder(t *testing.T, nFull int, storage []test.StorageMiner, options ...node.Option) ([]test.TestNode, []test.TestStorageNode) {
 	ctx := context.Background()
 	mn := mocknet.New(ctx)
 
@@ -344,6 +346,7 @@ func MockSbBuilder(t *testing.T, nFull int, storage []test.StorageMiner) ([]test
 	templ := &genesis.Template{
 		Accounts:         genaccs,
 		Miners:           genms,
+		NetworkName:      "test",
 		Timestamp:        uint64(time.Now().Unix()) - (build.BlockDelaySecs * 20000),
 		VerifregRootKey:  gen.DefaultVerifregRootkeyActor,
 		RemainderAccount: gen.DefaultRemainderAccountActor,
@@ -371,6 +374,7 @@ func MockSbBuilder(t *testing.T, nFull int, storage []test.StorageMiner) ([]test
 			node.Override(new(ffiwrapper.Verifier), mock.MockVerifier),
 
 			genesis,
+			node.Options(options...),
 		)
 		if err != nil {
 			t.Fatalf("%+v", err)
@@ -433,16 +437,16 @@ func MockSbBuilder(t *testing.T, nFull int, storage []test.StorageMiner) ([]test
 	return fulls, storers
 }
 
-func RPCBuilder(t *testing.T, nFull int, storage []test.StorageMiner) ([]test.TestNode, []test.TestStorageNode) {
-	return rpcWithBuilder(t, Builder, nFull, storage)
+func RPCBuilder(t *testing.T, nFull int, storage []test.StorageMiner, opts ...node.Option) ([]test.TestNode, []test.TestStorageNode) {
+	return rpcWithBuilder(t, Builder, nFull, storage, opts...)
 }
 
-func RPCMockSbBuilder(t *testing.T, nFull int, storage []test.StorageMiner) ([]test.TestNode, []test.TestStorageNode) {
-	return rpcWithBuilder(t, MockSbBuilder, nFull, storage)
+func RPCMockSbBuilder(t *testing.T, nFull int, storage []test.StorageMiner, opts ...node.Option) ([]test.TestNode, []test.TestStorageNode) {
+	return rpcWithBuilder(t, MockSbBuilder, nFull, storage, opts...)
 }
 
-func rpcWithBuilder(t *testing.T, b test.APIBuilder, nFull int, storage []test.StorageMiner) ([]test.TestNode, []test.TestStorageNode) {
-	fullApis, storaApis := b(t, nFull, storage)
+func rpcWithBuilder(t *testing.T, b test.APIBuilder, nFull int, storage []test.StorageMiner, opts ...node.Option) ([]test.TestNode, []test.TestStorageNode) {
+	fullApis, storaApis := b(t, nFull, storage, opts...)
 	fulls := make([]test.TestNode, nFull)
 	storers := make([]test.TestStorageNode, len(storage))
 
diff --git a/paychmgr/manager.go b/paychmgr/manager.go
index d9c568cbe..f2fc190c7 100644
--- a/paychmgr/manager.go
+++ b/paychmgr/manager.go
@@ -2,6 +2,7 @@ package paychmgr
 
 import (
 	"context"
+	"errors"
 	"sync"
 
 	"github.com/ipfs/go-cid"
@@ -12,7 +13,7 @@ import (
 
 	"github.com/filecoin-project/go-address"
 	"github.com/filecoin-project/go-state-types/crypto"
-	paych0 "github.com/filecoin-project/specs-actors/actors/builtin/paych"
+	"github.com/filecoin-project/go-state-types/network"
 
 	"github.com/filecoin-project/lotus/api"
 	"github.com/filecoin-project/lotus/chain/actors/adt"
@@ -25,6 +26,8 @@ import (
 
 var log = logging.Logger("paych")
 
+var errProofNotSupported = errors.New("payment channel proof parameter is not supported")
+
 // PaychAPI is used by dependency injection to pass the consituent APIs to NewManager()
 type PaychAPI struct {
 	fx.In
@@ -47,6 +50,7 @@ type paychAPI interface {
 	MpoolPushMessage(ctx context.Context, msg *types.Message, maxFee *api.MessageSendSpec) (*types.SignedMessage, error)
 	WalletHas(ctx context.Context, addr address.Address) (bool, error)
 	WalletSign(ctx context.Context, k address.Address, msg []byte) (*crypto.Signature, error)
+	StateNetworkVersion(context.Context, types.TipSetKey) (network.Version, error)
 }
 
 // managerAPI defines all methods needed by the manager
@@ -221,7 +225,7 @@ func (pm *Manager) GetChannelInfo(addr address.Address) (*ChannelInfo, error) {
 	return ca.getChannelInfo(addr)
 }
 
-func (pm *Manager) CreateVoucher(ctx context.Context, ch address.Address, voucher paych0.SignedVoucher) (*api.VoucherCreateResult, error) {
+func (pm *Manager) CreateVoucher(ctx context.Context, ch address.Address, voucher paych.SignedVoucher) (*api.VoucherCreateResult, error) {
 	ca, err := pm.accessorByAddress(ch)
 	if err != nil {
 		return nil, err
@@ -233,7 +237,7 @@ func (pm *Manager) CreateVoucher(ctx context.Context, ch address.Address, vouche
 // CheckVoucherValid checks if the given voucher is valid (is or could become spendable at some point).
 // If the channel is not in the store, fetches the channel from state (and checks that
 // the channel To address is owned by the wallet).
-func (pm *Manager) CheckVoucherValid(ctx context.Context, ch address.Address, sv *paych0.SignedVoucher) error {
+func (pm *Manager) CheckVoucherValid(ctx context.Context, ch address.Address, sv *paych.SignedVoucher) error {
 	// Get an accessor for the channel, creating it from state if necessary
 	ca, err := pm.inboundChannelAccessor(ctx, ch)
 	if err != nil {
@@ -245,35 +249,44 @@ func (pm *Manager) CheckVoucherValid(ctx context.Context, ch address.Address, sv
 }
 
 // CheckVoucherSpendable checks if the given voucher is currently spendable
-func (pm *Manager) CheckVoucherSpendable(ctx context.Context, ch address.Address, sv *paych0.SignedVoucher, secret []byte, proof []byte) (bool, error) {
+func (pm *Manager) CheckVoucherSpendable(ctx context.Context, ch address.Address, sv *paych.SignedVoucher, secret []byte, proof []byte) (bool, error) {
+	if len(proof) > 0 {
+		return false, errProofNotSupported
+	}
 	ca, err := pm.accessorByAddress(ch)
 	if err != nil {
 		return false, err
 	}
 
-	return ca.checkVoucherSpendable(ctx, ch, sv, secret, proof)
+	return ca.checkVoucherSpendable(ctx, ch, sv, secret)
 }
 
 // AddVoucherOutbound adds a voucher for an outbound channel.
 // Returns an error if the channel is not already in the store.
-func (pm *Manager) AddVoucherOutbound(ctx context.Context, ch address.Address, sv *paych0.SignedVoucher, proof []byte, minDelta types.BigInt) (types.BigInt, error) {
+func (pm *Manager) AddVoucherOutbound(ctx context.Context, ch address.Address, sv *paych.SignedVoucher, proof []byte, minDelta types.BigInt) (types.BigInt, error) {
+	if len(proof) > 0 {
+		return types.NewInt(0), errProofNotSupported
+	}
 	ca, err := pm.accessorByAddress(ch)
 	if err != nil {
 		return types.NewInt(0), err
 	}
-	return ca.addVoucher(ctx, ch, sv, proof, minDelta)
+	return ca.addVoucher(ctx, ch, sv, minDelta)
 }
 
 // AddVoucherInbound adds a voucher for an inbound channel.
 // If the channel is not in the store, fetches the channel from state (and checks that
 // the channel To address is owned by the wallet).
-func (pm *Manager) AddVoucherInbound(ctx context.Context, ch address.Address, sv *paych0.SignedVoucher, proof []byte, minDelta types.BigInt) (types.BigInt, error) {
+func (pm *Manager) AddVoucherInbound(ctx context.Context, ch address.Address, sv *paych.SignedVoucher, proof []byte, minDelta types.BigInt) (types.BigInt, error) {
+	if len(proof) > 0 {
+		return types.NewInt(0), errProofNotSupported
+	}
 	// Get an accessor for the channel, creating it from state if necessary
 	ca, err := pm.inboundChannelAccessor(ctx, ch)
 	if err != nil {
 		return types.BigInt{}, err
 	}
-	return ca.addVoucher(ctx, ch, sv, proof, minDelta)
+	return ca.addVoucher(ctx, ch, sv, minDelta)
 }
 
 // inboundChannelAccessor gets an accessor for the given channel. The channel
@@ -336,12 +349,15 @@ func (pm *Manager) trackInboundChannel(ctx context.Context, ch address.Address)
 	return pm.store.TrackChannel(stateCi)
 }
 
-func (pm *Manager) SubmitVoucher(ctx context.Context, ch address.Address, sv *paych0.SignedVoucher, secret []byte, proof []byte) (cid.Cid, error) {
+func (pm *Manager) SubmitVoucher(ctx context.Context, ch address.Address, sv *paych.SignedVoucher, secret []byte, proof []byte) (cid.Cid, error) {
+	if len(proof) > 0 {
+		return cid.Undef, errProofNotSupported
+	}
 	ca, err := pm.accessorByAddress(ch)
 	if err != nil {
 		return cid.Undef, err
 	}
-	return ca.submitVoucher(ctx, ch, sv, secret, proof)
+	return ca.submitVoucher(ctx, ch, sv, secret)
 }
 
 func (pm *Manager) AllocateLane(ch address.Address) (uint64, error) {
diff --git a/paychmgr/mock_test.go b/paychmgr/mock_test.go
index c761221d2..3393a3072 100644
--- a/paychmgr/mock_test.go
+++ b/paychmgr/mock_test.go
@@ -9,8 +9,10 @@ import (
 
 	"github.com/filecoin-project/go-address"
 	"github.com/filecoin-project/go-state-types/crypto"
+	"github.com/filecoin-project/go-state-types/network"
 
 	"github.com/filecoin-project/lotus/api"
+	"github.com/filecoin-project/lotus/build"
 	"github.com/filecoin-project/lotus/chain/actors/builtin/paych"
 	"github.com/filecoin-project/lotus/chain/types"
 	"github.com/filecoin-project/lotus/lib/sigs"
@@ -241,3 +243,7 @@ func (pchapi *mockPaychAPI) addSigningKey(key []byte) {
 
 	pchapi.signingKey = key
 }
+
+func (pchapi *mockPaychAPI) StateNetworkVersion(ctx context.Context, tsk types.TipSetKey) (network.Version, error) {
+	return build.NewestNetworkVersion, nil
+}
diff --git a/paychmgr/paych.go b/paychmgr/paych.go
index e67991911..c4ef3deb0 100644
--- a/paychmgr/paych.go
+++ b/paychmgr/paych.go
@@ -1,7 +1,6 @@
 package paychmgr
 
 import (
-	"bytes"
 	"context"
 	"fmt"
 
@@ -11,8 +10,6 @@ import (
 	"github.com/filecoin-project/go-address"
 	cborutil "github.com/filecoin-project/go-cbor-util"
 	"github.com/filecoin-project/go-state-types/big"
-	"github.com/filecoin-project/specs-actors/actors/builtin"
-	paych0 "github.com/filecoin-project/specs-actors/actors/builtin/paych"
 
 	"github.com/filecoin-project/lotus/api"
 	"github.com/filecoin-project/lotus/chain/actors"
@@ -85,6 +82,15 @@ func newChannelAccessor(pm *Manager, from address.Address, to address.Address) *
 	}
 }
 
+func (ca *channelAccessor) messageBuilder(ctx context.Context, from address.Address) (paych.MessageBuilder, error) {
+	nwVersion, err := ca.api.StateNetworkVersion(ctx, types.EmptyTSK)
+	if err != nil {
+		return nil, err
+	}
+
+	return paych.Message(actors.VersionForNetwork(nwVersion), from), nil
+}
+
 func (ca *channelAccessor) getChannelInfo(addr address.Address) (*ChannelInfo, error) {
 	ca.lk.Lock()
 	defer ca.lk.Unlock()
@@ -103,7 +109,7 @@ func (ca *channelAccessor) outboundActiveByFromTo(from, to address.Address) (*Ch
 // nonce, signing the voucher and storing it in the local datastore.
 // If there are not enough funds in the channel to create the voucher, returns
 // the shortfall in funds.
-func (ca *channelAccessor) createVoucher(ctx context.Context, ch address.Address, voucher paych0.SignedVoucher) (*api.VoucherCreateResult, error) {
+func (ca *channelAccessor) createVoucher(ctx context.Context, ch address.Address, voucher paych.SignedVoucher) (*api.VoucherCreateResult, error) {
 	ca.lk.Lock()
 	defer ca.lk.Unlock()
 
@@ -133,7 +139,7 @@ func (ca *channelAccessor) createVoucher(ctx context.Context, ch address.Address
 	sv.Signature = sig
 
 	// Store the voucher
-	if _, err := ca.addVoucherUnlocked(ctx, ch, sv, nil, types.NewInt(0)); err != nil {
+	if _, err := ca.addVoucherUnlocked(ctx, ch, sv, types.NewInt(0)); err != nil {
 		// If there are not enough funds in the channel to cover the voucher,
 		// return a voucher create result with the shortfall
 		var ife insufficientFundsErr
@@ -162,14 +168,14 @@ func (ca *channelAccessor) nextNonceForLane(ci *ChannelInfo, lane uint64) uint64
 	return maxnonce + 1
 }
 
-func (ca *channelAccessor) checkVoucherValid(ctx context.Context, ch address.Address, sv *paych0.SignedVoucher) (map[uint64]paych.LaneState, error) {
+func (ca *channelAccessor) checkVoucherValid(ctx context.Context, ch address.Address, sv *paych.SignedVoucher) (map[uint64]paych.LaneState, error) {
 	ca.lk.Lock()
 	defer ca.lk.Unlock()
 
 	return ca.checkVoucherValidUnlocked(ctx, ch, sv)
 }
 
-func (ca *channelAccessor) checkVoucherValidUnlocked(ctx context.Context, ch address.Address, sv *paych0.SignedVoucher) (map[uint64]paych.LaneState, error) {
+func (ca *channelAccessor) checkVoucherValidUnlocked(ctx context.Context, ch address.Address, sv *paych.SignedVoucher) (map[uint64]paych.LaneState, error) {
 	if sv.ChannelAddr != ch {
 		return nil, xerrors.Errorf("voucher ChannelAddr doesn't match channel address, got %s, expected %s", sv.ChannelAddr, ch)
 	}
@@ -265,7 +271,7 @@ func (ca *channelAccessor) checkVoucherValidUnlocked(ctx context.Context, ch add
 	return laneStates, nil
 }
 
-func (ca *channelAccessor) checkVoucherSpendable(ctx context.Context, ch address.Address, sv *paych0.SignedVoucher, secret []byte, proof []byte) (bool, error) {
+func (ca *channelAccessor) checkVoucherSpendable(ctx context.Context, ch address.Address, sv *paych.SignedVoucher, secret []byte) (bool, error) {
 	ca.lk.Lock()
 	defer ca.lk.Unlock()
 
@@ -288,37 +294,17 @@ func (ca *channelAccessor) checkVoucherSpendable(ctx context.Context, ch address
 		return false, nil
 	}
 
-	// If proof is needed and wasn't supplied as a parameter, get it from the
-	// datastore
-	if sv.Extra != nil && proof == nil {
-		vi, err := ci.infoForVoucher(sv)
-		if err != nil {
-			return false, err
-		}
-
-		if vi.Proof != nil {
-			log.Info("CheckVoucherSpendable: using stored proof")
-			proof = vi.Proof
-		} else {
-			log.Warn("CheckVoucherSpendable: nil proof for voucher with validation")
-		}
-	}
-
-	enc, err := actors.SerializeParams(&paych0.UpdateChannelStateParams{
-		Sv:     *sv,
-		Secret: secret,
-		Proof:  proof,
-	})
+	mb, err := ca.messageBuilder(ctx, recipient)
 	if err != nil {
 		return false, err
 	}
 
-	ret, err := ca.api.Call(ctx, &types.Message{
-		From:   recipient,
-		To:     ch,
-		Method: builtin.MethodsPaych.UpdateChannelState,
-		Params: enc,
-	}, nil)
+	mes, err := mb.Update(ch, sv, secret)
+	if err != nil {
+		return false, err
+	}
+
+	ret, err := ca.api.Call(ctx, mes, nil)
 	if err != nil {
 		return false, err
 	}
@@ -339,44 +325,31 @@ func (ca *channelAccessor) getPaychRecipient(ctx context.Context, ch address.Add
 	return state.To()
 }
 
-func (ca *channelAccessor) addVoucher(ctx context.Context, ch address.Address, sv *paych0.SignedVoucher, proof []byte, minDelta types.BigInt) (types.BigInt, error) {
+func (ca *channelAccessor) addVoucher(ctx context.Context, ch address.Address, sv *paych.SignedVoucher, minDelta types.BigInt) (types.BigInt, error) {
 	ca.lk.Lock()
 	defer ca.lk.Unlock()
 
-	return ca.addVoucherUnlocked(ctx, ch, sv, proof, minDelta)
+	return ca.addVoucherUnlocked(ctx, ch, sv, minDelta)
 }
 
-func (ca *channelAccessor) addVoucherUnlocked(ctx context.Context, ch address.Address, sv *paych0.SignedVoucher, proof []byte, minDelta types.BigInt) (types.BigInt, error) {
+func (ca *channelAccessor) addVoucherUnlocked(ctx context.Context, ch address.Address, sv *paych.SignedVoucher, minDelta types.BigInt) (types.BigInt, error) {
 	ci, err := ca.store.ByAddress(ch)
 	if err != nil {
 		return types.BigInt{}, err
 	}
 
 	// Check if the voucher has already been added
-	for i, v := range ci.Vouchers {
+	for _, v := range ci.Vouchers {
 		eq, err := cborutil.Equals(sv, v.Voucher)
 		if err != nil {
 			return types.BigInt{}, err
 		}
-		if !eq {
-			continue
+		if eq {
+			// Ignore the duplicate voucher.
+			log.Warnf("AddVoucher: voucher re-added")
+			return types.NewInt(0), nil
 		}
 
-		// This is a duplicate voucher.
-		// Update the proof on the existing voucher
-		if len(proof) > 0 && !bytes.Equal(v.Proof, proof) {
-			log.Warnf("AddVoucher: adding proof to stored voucher")
-			ci.Vouchers[i] = &VoucherInfo{
-				Voucher: v.Voucher,
-				Proof:   proof,
-			}
-
-			return types.NewInt(0), ca.store.putChannelInfo(ci)
-		}
-
-		// Otherwise just ignore the duplicate voucher
-		log.Warnf("AddVoucher: voucher re-added with matching proof")
-		return types.NewInt(0), nil
 	}
 
 	// Check voucher validity
@@ -403,7 +376,6 @@ func (ca *channelAccessor) addVoucherUnlocked(ctx context.Context, ch address.Ad
 
 	ci.Vouchers = append(ci.Vouchers, &VoucherInfo{
 		Voucher: sv,
-		Proof:   proof,
 	})
 
 	if ci.NextLane <= sv.Lane {
@@ -413,7 +385,7 @@ func (ca *channelAccessor) addVoucherUnlocked(ctx context.Context, ch address.Ad
 	return delta, ca.store.putChannelInfo(ci)
 }
 
-func (ca *channelAccessor) submitVoucher(ctx context.Context, ch address.Address, sv *paych0.SignedVoucher, secret []byte, proof []byte) (cid.Cid, error) {
+func (ca *channelAccessor) submitVoucher(ctx context.Context, ch address.Address, sv *paych.SignedVoucher, secret []byte) (cid.Cid, error) {
 	ca.lk.Lock()
 	defer ca.lk.Unlock()
 
@@ -422,21 +394,6 @@ func (ca *channelAccessor) submitVoucher(ctx context.Context, ch address.Address
 		return cid.Undef, err
 	}
 
-	// If voucher needs proof, and none was supplied, check datastore for proof
-	if sv.Extra != nil && proof == nil {
-		vi, err := ci.infoForVoucher(sv)
-		if err != nil {
-			return cid.Undef, err
-		}
-
-		if vi.Proof != nil {
-			log.Info("SubmitVoucher: using stored proof")
-			proof = vi.Proof
-		} else {
-			log.Warn("SubmitVoucher: nil proof for voucher with validation")
-		}
-	}
-
 	has, err := ci.hasVoucher(sv)
 	if err != nil {
 		return cid.Undef, err
@@ -454,21 +411,14 @@ func (ca *channelAccessor) submitVoucher(ctx context.Context, ch address.Address
 		}
 	}
 
-	enc, err := actors.SerializeParams(&paych0.UpdateChannelStateParams{
-		Sv:     *sv,
-		Secret: secret,
-		Proof:  proof,
-	})
+	mb, err := ca.messageBuilder(ctx, ci.Control)
 	if err != nil {
 		return cid.Undef, err
 	}
 
-	msg := &types.Message{
-		From:   ci.Control,
-		To:     ch,
-		Value:  types.NewInt(0),
-		Method: builtin.MethodsPaych.UpdateChannelState,
-		Params: enc,
+	msg, err := mb.Update(ch, sv, secret)
+	if err != nil {
+		return cid.Undef, err
 	}
 
 	smsg, err := ca.api.MpoolPushMessage(ctx, msg, nil)
@@ -481,7 +431,6 @@ func (ca *channelAccessor) submitVoucher(ctx context.Context, ch address.Address
 		// Add the voucher to the channel
 		ci.Vouchers = append(ci.Vouchers, &VoucherInfo{
 			Voucher: sv,
-			Proof:   proof,
 		})
 	}
 
@@ -568,7 +517,7 @@ func (ca *channelAccessor) laneState(state paych.State, ch address.Address) (map
 }
 
 // Get the total redeemed amount across all lanes, after applying the voucher
-func (ca *channelAccessor) totalRedeemedWithVoucher(laneStates map[uint64]paych.LaneState, sv *paych0.SignedVoucher) (big.Int, error) {
+func (ca *channelAccessor) totalRedeemedWithVoucher(laneStates map[uint64]paych.LaneState, sv *paych.SignedVoucher) (big.Int, error) {
 	// TODO: merges
 	if len(sv.Merges) != 0 {
 		return big.Int{}, xerrors.Errorf("dont currently support paych lane merges")
@@ -621,11 +570,13 @@ func (ca *channelAccessor) settle(ctx context.Context, ch address.Address) (cid.
 		return cid.Undef, err
 	}
 
-	msg := &types.Message{
-		To:     ch,
-		From:   ci.Control,
-		Value:  types.NewInt(0),
-		Method: builtin.MethodsPaych.Settle,
+	mb, err := ca.messageBuilder(ctx, ci.Control)
+	if err != nil {
+		return cid.Undef, err
+	}
+	msg, err := mb.Settle(ch)
+	if err != nil {
+		return cid.Undef, err
 	}
 	smgs, err := ca.api.MpoolPushMessage(ctx, msg, nil)
 	if err != nil {
@@ -650,11 +601,14 @@ func (ca *channelAccessor) collect(ctx context.Context, ch address.Address) (cid
 		return cid.Undef, err
 	}
 
-	msg := &types.Message{
-		To:     ch,
-		From:   ci.Control,
-		Value:  types.NewInt(0),
-		Method: builtin.MethodsPaych.Collect,
+	mb, err := ca.messageBuilder(ctx, ci.Control)
+	if err != nil {
+		return cid.Undef, err
+	}
+
+	msg, err := mb.Collect(ch)
+	if err != nil {
+		return cid.Undef, err
 	}
 
 	smsg, err := ca.api.MpoolPushMessage(ctx, msg, nil)
diff --git a/paychmgr/paych_test.go b/paychmgr/paych_test.go
index 56e7e9089..fcd3d50a8 100644
--- a/paychmgr/paych_test.go
+++ b/paychmgr/paych_test.go
@@ -15,8 +15,8 @@ import (
 	"github.com/filecoin-project/go-state-types/big"
 	"github.com/filecoin-project/go-state-types/crypto"
 	"github.com/filecoin-project/specs-actors/actors/builtin"
-	paych0 "github.com/filecoin-project/specs-actors/actors/builtin/paych"
 	tutils "github.com/filecoin-project/specs-actors/support/testing"
+	paych2 "github.com/filecoin-project/specs-actors/v2/actors/builtin/paych"
 
 	"github.com/filecoin-project/lotus/api"
 	"github.com/filecoin-project/lotus/chain/actors/builtin/paych"
@@ -237,7 +237,7 @@ func TestCreateVoucher(t *testing.T) {
 
 	// Create a voucher in lane 1
 	voucherLane1Amt := big.NewInt(5)
-	voucher := paych0.SignedVoucher{
+	voucher := paych2.SignedVoucher{
 		Lane:   1,
 		Amount: voucherLane1Amt,
 	}
@@ -252,7 +252,7 @@ func TestCreateVoucher(t *testing.T) {
 
 	// Create a voucher in lane 1 again, with a higher amount
 	voucherLane1Amt = big.NewInt(8)
-	voucher = paych0.SignedVoucher{
+	voucher = paych2.SignedVoucher{
 		Lane:   1,
 		Amount: voucherLane1Amt,
 	}
@@ -267,7 +267,7 @@ func TestCreateVoucher(t *testing.T) {
 	// Create a voucher in lane 2 that covers all the remaining funds
 	// in the channel
 	voucherLane2Amt := big.Sub(s.amt, voucherLane1Amt)
-	voucher = paych0.SignedVoucher{
+	voucher = paych2.SignedVoucher{
 		Lane:   2,
 		Amount: voucherLane2Amt,
 	}
@@ -281,7 +281,7 @@ func TestCreateVoucher(t *testing.T) {
 	// Create a voucher in lane 2 that exceeds the remaining funds in the
 	// channel
 	voucherLane2Amt = big.Add(voucherLane2Amt, big.NewInt(1))
-	voucher = paych0.SignedVoucher{
+	voucher = paych2.SignedVoucher{
 		Lane:   2,
 		Amount: voucherLane2Amt,
 	}
@@ -450,53 +450,6 @@ func TestAllocateLaneWithExistingLaneState(t *testing.T) {
 	require.EqualValues(t, 3, lane)
 }
 
-func TestAddVoucherProof(t *testing.T) {
-	ctx := context.Background()
-
-	// Set up a manager with a single payment channel
-	s := testSetupMgrWithChannel(t)
-
-	nonce := uint64(1)
-	voucherAmount := big.NewInt(1)
-	minDelta := big.NewInt(0)
-	voucherAmount = big.NewInt(2)
-	voucherLane := uint64(1)
-
-	// Add a voucher with no proof
-	var proof []byte
-	sv := createTestVoucher(t, s.ch, voucherLane, nonce, voucherAmount, s.fromKeyPrivate)
-	_, err := s.mgr.AddVoucherOutbound(ctx, s.ch, sv, nil, minDelta)
-	require.NoError(t, err)
-
-	// Expect one voucher with no proof
-	ci, err := s.mgr.GetChannelInfo(s.ch)
-	require.NoError(t, err)
-	require.Len(t, ci.Vouchers, 1)
-	require.Len(t, ci.Vouchers[0].Proof, 0)
-
-	// Add same voucher with no proof
-	voucherLane = uint64(1)
-	_, err = s.mgr.AddVoucherOutbound(ctx, s.ch, sv, proof, minDelta)
-	require.NoError(t, err)
-
-	// Expect one voucher with no proof
-	ci, err = s.mgr.GetChannelInfo(s.ch)
-	require.NoError(t, err)
-	require.Len(t, ci.Vouchers, 1)
-	require.Len(t, ci.Vouchers[0].Proof, 0)
-
-	// Add same voucher with proof
-	proof = []byte{1}
-	_, err = s.mgr.AddVoucherOutbound(ctx, s.ch, sv, proof, minDelta)
-	require.NoError(t, err)
-
-	// Should add proof to existing voucher
-	ci, err = s.mgr.GetChannelInfo(s.ch)
-	require.NoError(t, err)
-	require.Len(t, ci.Vouchers, 1)
-	require.Len(t, ci.Vouchers[0].Proof, 1)
-}
-
 func TestAddVoucherInboundWalletKey(t *testing.T) {
 	ctx := context.Background()
 
@@ -644,10 +597,9 @@ func TestCheckSpendable(t *testing.T) {
 	voucherAmount := big.NewInt(1)
 	voucher := createTestVoucherWithExtra(t, s.ch, voucherLane, nonce, voucherAmount, s.fromKeyPrivate)
 
-	// Add voucher with proof
+	// Add voucher
 	minDelta := big.NewInt(0)
-	proof := []byte("proof")
-	_, err := s.mgr.AddVoucherInbound(ctx, s.ch, voucher, proof, minDelta)
+	_, err := s.mgr.AddVoucherInbound(ctx, s.ch, voucher, nil, minDelta)
 	require.NoError(t, err)
 
 	// Return success exit code from VM call, which indicates that voucher is
@@ -661,33 +613,17 @@ func TestCheckSpendable(t *testing.T) {
 
 	// Check that spendable is true
 	secret := []byte("secret")
-	otherProof := []byte("other proof")
-	spendable, err := s.mgr.CheckVoucherSpendable(ctx, s.ch, voucher, secret, otherProof)
+	spendable, err := s.mgr.CheckVoucherSpendable(ctx, s.ch, voucher, secret, nil)
 	require.NoError(t, err)
 	require.True(t, spendable)
 
-	// Check that the secret and proof were passed through correctly
+	// Check that the secret was passed through correctly
 	lastCall := s.mock.getLastCall()
-	var p paych0.UpdateChannelStateParams
+	var p paych2.UpdateChannelStateParams
 	err = p.UnmarshalCBOR(bytes.NewReader(lastCall.Params))
 	require.NoError(t, err)
-	require.Equal(t, otherProof, p.Proof)
 	require.Equal(t, secret, p.Secret)
 
-	// Check that if no proof is supplied, the proof supplied to add voucher
-	// above is used
-	secret2 := []byte("secret2")
-	spendable, err = s.mgr.CheckVoucherSpendable(ctx, s.ch, voucher, secret2, nil)
-	require.NoError(t, err)
-	require.True(t, spendable)
-
-	lastCall = s.mock.getLastCall()
-	var p2 paych0.UpdateChannelStateParams
-	err = p2.UnmarshalCBOR(bytes.NewReader(lastCall.Params))
-	require.NoError(t, err)
-	require.Equal(t, proof, p2.Proof)
-	require.Equal(t, secret2, p2.Secret)
-
 	// Check that if VM call returns non-success exit code, spendable is false
 	s.mock.setCallResponse(&api.InvocResult{
 		MsgRct: &types.MessageReceipt{
@@ -725,73 +661,48 @@ func TestSubmitVoucher(t *testing.T) {
 	voucherAmount := big.NewInt(1)
 	voucher := createTestVoucherWithExtra(t, s.ch, voucherLane, nonce, voucherAmount, s.fromKeyPrivate)
 
-	// Add voucher with proof
+	// Add voucher
 	minDelta := big.NewInt(0)
-	addVoucherProof := []byte("proof")
-	_, err := s.mgr.AddVoucherInbound(ctx, s.ch, voucher, addVoucherProof, minDelta)
+	_, err := s.mgr.AddVoucherInbound(ctx, s.ch, voucher, nil, minDelta)
 	require.NoError(t, err)
 
 	// Submit voucher
 	secret := []byte("secret")
-	submitProof := []byte("submit proof")
-	submitCid, err := s.mgr.SubmitVoucher(ctx, s.ch, voucher, secret, submitProof)
+	submitCid, err := s.mgr.SubmitVoucher(ctx, s.ch, voucher, secret, nil)
 	require.NoError(t, err)
 
-	// Check that the secret and proof were passed through correctly
+	// Check that the secret was passed through correctly
 	msg := s.mock.pushedMessages(submitCid)
-	var p paych0.UpdateChannelStateParams
+	var p paych2.UpdateChannelStateParams
 	err = p.UnmarshalCBOR(bytes.NewReader(msg.Message.Params))
 	require.NoError(t, err)
-	require.Equal(t, submitProof, p.Proof)
 	require.Equal(t, secret, p.Secret)
 
-	// Check that if no proof is supplied to submit voucher, the proof supplied
-	// to add voucher is used
-	nonce++
-	voucherAmount = big.NewInt(2)
-	addVoucherProof2 := []byte("proof2")
-	secret2 := []byte("secret2")
-	voucher = createTestVoucherWithExtra(t, s.ch, voucherLane, nonce, voucherAmount, s.fromKeyPrivate)
-	_, err = s.mgr.AddVoucherInbound(ctx, s.ch, voucher, addVoucherProof2, minDelta)
-	require.NoError(t, err)
-
-	submitCid, err = s.mgr.SubmitVoucher(ctx, s.ch, voucher, secret2, nil)
-	require.NoError(t, err)
-
-	msg = s.mock.pushedMessages(submitCid)
-	var p2 paych0.UpdateChannelStateParams
-	err = p2.UnmarshalCBOR(bytes.NewReader(msg.Message.Params))
-	require.NoError(t, err)
-	require.Equal(t, addVoucherProof2, p2.Proof)
-	require.Equal(t, secret2, p2.Secret)
-
 	// Submit a voucher without first adding it
 	nonce++
 	voucherAmount = big.NewInt(3)
 	secret3 := []byte("secret2")
-	proof3 := []byte("proof3")
 	voucher = createTestVoucherWithExtra(t, s.ch, voucherLane, nonce, voucherAmount, s.fromKeyPrivate)
-	submitCid, err = s.mgr.SubmitVoucher(ctx, s.ch, voucher, secret3, proof3)
+	submitCid, err = s.mgr.SubmitVoucher(ctx, s.ch, voucher, secret3, nil)
 	require.NoError(t, err)
 
 	msg = s.mock.pushedMessages(submitCid)
-	var p3 paych0.UpdateChannelStateParams
+	var p3 paych2.UpdateChannelStateParams
 	err = p3.UnmarshalCBOR(bytes.NewReader(msg.Message.Params))
 	require.NoError(t, err)
-	require.Equal(t, proof3, p3.Proof)
 	require.Equal(t, secret3, p3.Secret)
 
 	// Verify that vouchers are marked as submitted
 	vis, err := s.mgr.ListVouchers(ctx, s.ch)
 	require.NoError(t, err)
-	require.Len(t, vis, 3)
+	require.Len(t, vis, 2)
 
 	for _, vi := range vis {
 		require.True(t, vi.Submitted)
 	}
 
 	// Attempting to submit the same voucher again should fail
-	_, err = s.mgr.SubmitVoucher(ctx, s.ch, voucher, secret2, nil)
+	_, err = s.mgr.SubmitVoucher(ctx, s.ch, voucher, secret3, nil)
 	require.Error(t, err)
 }
 
@@ -862,8 +773,8 @@ func testGenerateKeyPair(t *testing.T) ([]byte, []byte) {
 	return priv, pub
 }
 
-func createTestVoucher(t *testing.T, ch address.Address, voucherLane uint64, nonce uint64, voucherAmount big.Int, key []byte) *paych0.SignedVoucher {
-	sv := &paych0.SignedVoucher{
+func createTestVoucher(t *testing.T, ch address.Address, voucherLane uint64, nonce uint64, voucherAmount big.Int, key []byte) *paych2.SignedVoucher {
+	sv := &paych2.SignedVoucher{
 		ChannelAddr: ch,
 		Lane:        voucherLane,
 		Nonce:       nonce,
@@ -878,13 +789,13 @@ func createTestVoucher(t *testing.T, ch address.Address, voucherLane uint64, non
 	return sv
 }
 
-func createTestVoucherWithExtra(t *testing.T, ch address.Address, voucherLane uint64, nonce uint64, voucherAmount big.Int, key []byte) *paych0.SignedVoucher {
-	sv := &paych0.SignedVoucher{
+func createTestVoucherWithExtra(t *testing.T, ch address.Address, voucherLane uint64, nonce uint64, voucherAmount big.Int, key []byte) *paych2.SignedVoucher {
+	sv := &paych2.SignedVoucher{
 		ChannelAddr: ch,
 		Lane:        voucherLane,
 		Nonce:       nonce,
 		Amount:      voucherAmount,
-		Extra: &paych0.ModVerifyParams{
+		Extra: &paych2.ModVerifyParams{
 			Actor: tutils.NewActorAddr(t, "act"),
 		},
 	}
@@ -902,13 +813,13 @@ type mockBestSpendableAPI struct {
 	mgr *Manager
 }
 
-func (m *mockBestSpendableAPI) PaychVoucherList(ctx context.Context, ch address.Address) ([]*paych0.SignedVoucher, error) {
+func (m *mockBestSpendableAPI) PaychVoucherList(ctx context.Context, ch address.Address) ([]*paych2.SignedVoucher, error) {
 	vi, err := m.mgr.ListVouchers(ctx, ch)
 	if err != nil {
 		return nil, err
 	}
 
-	out := make([]*paych0.SignedVoucher, len(vi))
+	out := make([]*paych2.SignedVoucher, len(vi))
 	for k, v := range vi {
 		out[k] = v.Voucher
 	}
@@ -916,7 +827,7 @@ func (m *mockBestSpendableAPI) PaychVoucherList(ctx context.Context, ch address.
 	return out, nil
 }
 
-func (m *mockBestSpendableAPI) PaychVoucherCheckSpendable(ctx context.Context, ch address.Address, voucher *paych0.SignedVoucher, secret []byte, proof []byte) (bool, error) {
+func (m *mockBestSpendableAPI) PaychVoucherCheckSpendable(ctx context.Context, ch address.Address, voucher *paych2.SignedVoucher, secret []byte, proof []byte) (bool, error) {
 	return m.mgr.CheckVoucherSpendable(ctx, ch, voucher, secret, proof)
 }
 
diff --git a/paychmgr/paychget_test.go b/paychmgr/paychget_test.go
index e35ae8371..9f19dd13d 100644
--- a/paychmgr/paychget_test.go
+++ b/paychmgr/paychget_test.go
@@ -15,9 +15,9 @@ 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/specs-actors/actors/builtin"
-	init_ "github.com/filecoin-project/specs-actors/actors/builtin/init"
-	tutils "github.com/filecoin-project/specs-actors/support/testing"
+	"github.com/filecoin-project/specs-actors/v2/actors/builtin"
+	init2 "github.com/filecoin-project/specs-actors/v2/actors/builtin/init"
+	tutils "github.com/filecoin-project/specs-actors/v2/support/testing"
 
 	lotusinit "github.com/filecoin-project/lotus/chain/actors/builtin/init"
 	"github.com/filecoin-project/lotus/chain/actors/builtin/paych"
@@ -26,7 +26,7 @@ import (
 )
 
 func testChannelResponse(t *testing.T, ch address.Address) types.MessageReceipt {
-	createChannelRet := init_.ExecReturn{
+	createChannelRet := init2.ExecReturn{
 		IDAddress:     ch,
 		RobustAddress: ch,
 	}
diff --git a/paychmgr/settler/settler.go b/paychmgr/settler/settler.go
index 654ed66cc..02fe9256e 100644
--- a/paychmgr/settler/settler.go
+++ b/paychmgr/settler/settler.go
@@ -15,10 +15,10 @@ import (
 	"github.com/filecoin-project/go-state-types/abi"
 
 	builtin0 "github.com/filecoin-project/specs-actors/actors/builtin"
-	paych0 "github.com/filecoin-project/specs-actors/actors/builtin/paych"
 
 	"github.com/filecoin-project/lotus/api"
 	"github.com/filecoin-project/lotus/build"
+	"github.com/filecoin-project/lotus/chain/actors/builtin/paych"
 	"github.com/filecoin-project/lotus/chain/events"
 	"github.com/filecoin-project/lotus/chain/types"
 	"github.com/filecoin-project/lotus/node/impl/full"
@@ -39,9 +39,9 @@ type API struct {
 type settlerAPI interface {
 	PaychList(context.Context) ([]address.Address, error)
 	PaychStatus(context.Context, address.Address) (*api.PaychStatus, error)
-	PaychVoucherCheckSpendable(context.Context, address.Address, *paych0.SignedVoucher, []byte, []byte) (bool, error)
-	PaychVoucherList(context.Context, address.Address) ([]*paych0.SignedVoucher, error)
-	PaychVoucherSubmit(context.Context, address.Address, *paych0.SignedVoucher, []byte, []byte) (cid.Cid, error)
+	PaychVoucherCheckSpendable(context.Context, address.Address, *paych.SignedVoucher, []byte, []byte) (bool, error)
+	PaychVoucherList(context.Context, address.Address) ([]*paych.SignedVoucher, error)
+	PaychVoucherSubmit(context.Context, address.Address, *paych.SignedVoucher, []byte, []byte) (cid.Cid, error)
 	StateWaitMsg(ctx context.Context, cid cid.Cid, confidence uint64) (*api.MsgLookup, error)
 }
 
@@ -86,7 +86,7 @@ func (pcs *paymentChannelSettler) messageHandler(msg *types.Message, rec *types.
 		if err != nil {
 			return true, err
 		}
-		go func(voucher *paych0.SignedVoucher, submitMessageCID cid.Cid) {
+		go func(voucher *paych.SignedVoucher, submitMessageCID cid.Cid) {
 			defer wg.Done()
 			msgLookup, err := pcs.api.StateWaitMsg(pcs.ctx, submitMessageCID, build.MessageConfidence)
 			if err != nil {
diff --git a/paychmgr/simple.go b/paychmgr/simple.go
index ca778829f..253075604 100644
--- a/paychmgr/simple.go
+++ b/paychmgr/simple.go
@@ -12,14 +12,11 @@ import (
 
 	"github.com/filecoin-project/go-address"
 	"github.com/filecoin-project/go-state-types/big"
-	"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"
+
+	init2 "github.com/filecoin-project/specs-actors/v2/actors/builtin/init"
 
 	"github.com/filecoin-project/lotus/api"
 	"github.com/filecoin-project/lotus/build"
-	"github.com/filecoin-project/lotus/chain/actors"
-	lotusinit "github.com/filecoin-project/lotus/chain/actors/builtin/init"
 	"github.com/filecoin-project/lotus/chain/types"
 )
 
@@ -387,25 +384,13 @@ func (ca *channelAccessor) processTask(ctx context.Context, amt types.BigInt) *p
 
 // createPaych sends a message to create the channel and returns the message cid
 func (ca *channelAccessor) createPaych(ctx context.Context, amt types.BigInt) (cid.Cid, error) {
-	params, aerr := actors.SerializeParams(&paych0.ConstructorParams{From: ca.from, To: ca.to})
-	if aerr != nil {
-		return cid.Undef, aerr
+	mb, err := ca.messageBuilder(ctx, ca.from)
+	if err != nil {
+		return cid.Undef, err
 	}
-
-	enc, aerr := actors.SerializeParams(&init0.ExecParams{
-		CodeCID:           builtin.PaymentChannelActorCodeID,
-		ConstructorParams: params,
-	})
-	if aerr != nil {
-		return cid.Undef, aerr
-	}
-
-	msg := &types.Message{
-		To:     lotusinit.Address,
-		From:   ca.from,
-		Value:  amt,
-		Method: builtin.MethodsInit.Exec,
-		Params: enc,
+	msg, err := mb.Create(ca.to, amt)
+	if err != nil {
+		return cid.Undef, err
 	}
 
 	smsg, err := ca.api.MpoolPushMessage(ctx, msg, nil)
@@ -457,7 +442,10 @@ func (ca *channelAccessor) waitPaychCreateMsg(channelID string, mcid cid.Cid) er
 		return err
 	}
 
-	var decodedReturn init0.ExecReturn
+	// TODO: ActorUpgrade abstract over this.
+	// This "works" because it hasn't changed from v0 to v2, but we still
+	// need an abstraction here.
+	var decodedReturn init2.ExecReturn
 	err = decodedReturn.UnmarshalCBOR(bytes.NewReader(mwait.Receipt.Return))
 	if err != nil {
 		log.Error(err)
diff --git a/paychmgr/store.go b/paychmgr/store.go
index 23916669e..a17ad1fcd 100644
--- a/paychmgr/store.go
+++ b/paychmgr/store.go
@@ -17,11 +17,10 @@ import (
 	"github.com/ipfs/go-datastore/namespace"
 	dsq "github.com/ipfs/go-datastore/query"
 
-	paych0 "github.com/filecoin-project/specs-actors/actors/builtin/paych"
-
 	"github.com/filecoin-project/go-address"
 	cborrpc "github.com/filecoin-project/go-cbor-util"
 
+	"github.com/filecoin-project/lotus/chain/actors/builtin/paych"
 	"github.com/filecoin-project/lotus/node/modules/dtypes"
 )
 
@@ -49,8 +48,8 @@ const (
 )
 
 type VoucherInfo struct {
-	Voucher   *paych0.SignedVoucher
-	Proof     []byte
+	Voucher   *paych.SignedVoucher
+	Proof     []byte // ignored
 	Submitted bool
 }
 
@@ -103,7 +102,7 @@ func (ci *ChannelInfo) to() address.Address {
 
 // infoForVoucher gets the VoucherInfo for the given voucher.
 // returns nil if the channel doesn't have the voucher.
-func (ci *ChannelInfo) infoForVoucher(sv *paych0.SignedVoucher) (*VoucherInfo, error) {
+func (ci *ChannelInfo) infoForVoucher(sv *paych.SignedVoucher) (*VoucherInfo, error) {
 	for _, v := range ci.Vouchers {
 		eq, err := cborutil.Equals(sv, v.Voucher)
 		if err != nil {
@@ -116,7 +115,7 @@ func (ci *ChannelInfo) infoForVoucher(sv *paych0.SignedVoucher) (*VoucherInfo, e
 	return nil, nil
 }
 
-func (ci *ChannelInfo) hasVoucher(sv *paych0.SignedVoucher) (bool, error) {
+func (ci *ChannelInfo) hasVoucher(sv *paych.SignedVoucher) (bool, error) {
 	vi, err := ci.infoForVoucher(sv)
 	return vi != nil, err
 }
@@ -124,7 +123,7 @@ func (ci *ChannelInfo) hasVoucher(sv *paych0.SignedVoucher) (bool, error) {
 // markVoucherSubmitted marks the voucher, and any vouchers of lower nonce
 // in the same lane, as being submitted.
 // Note: This method doesn't write anything to the store.
-func (ci *ChannelInfo) markVoucherSubmitted(sv *paych0.SignedVoucher) error {
+func (ci *ChannelInfo) markVoucherSubmitted(sv *paych.SignedVoucher) error {
 	vi, err := ci.infoForVoucher(sv)
 	if err != nil {
 		return err
@@ -148,7 +147,7 @@ func (ci *ChannelInfo) markVoucherSubmitted(sv *paych0.SignedVoucher) error {
 }
 
 // wasVoucherSubmitted returns true if the voucher has been submitted
-func (ci *ChannelInfo) wasVoucherSubmitted(sv *paych0.SignedVoucher) (bool, error) {
+func (ci *ChannelInfo) wasVoucherSubmitted(sv *paych.SignedVoucher) (bool, error) {
 	vi, err := ci.infoForVoucher(sv)
 	if err != nil {
 		return false, err
@@ -277,7 +276,7 @@ func (ps *Store) VouchersForPaych(ch address.Address) ([]*VoucherInfo, error) {
 	return ci.Vouchers, nil
 }
 
-func (ps *Store) MarkVoucherSubmitted(ci *ChannelInfo, sv *paych0.SignedVoucher) error {
+func (ps *Store) MarkVoucherSubmitted(ci *ChannelInfo, sv *paych.SignedVoucher) error {
 	err := ci.markVoucherSubmitted(sv)
 	if err != nil {
 		return err
diff --git a/paychmgr/util.go b/paychmgr/util.go
index 2a8181c15..8e5dd4fab 100644
--- a/paychmgr/util.go
+++ b/paychmgr/util.go
@@ -5,21 +5,21 @@ import (
 
 	"github.com/filecoin-project/go-address"
 
-	paych0 "github.com/filecoin-project/specs-actors/actors/builtin/paych"
+	"github.com/filecoin-project/lotus/chain/actors/builtin/paych"
 )
 
 type BestSpendableAPI interface {
-	PaychVoucherList(context.Context, address.Address) ([]*paych0.SignedVoucher, error)
-	PaychVoucherCheckSpendable(context.Context, address.Address, *paych0.SignedVoucher, []byte, []byte) (bool, error)
+	PaychVoucherList(context.Context, address.Address) ([]*paych.SignedVoucher, error)
+	PaychVoucherCheckSpendable(context.Context, address.Address, *paych.SignedVoucher, []byte, []byte) (bool, error)
 }
 
-func BestSpendableByLane(ctx context.Context, api BestSpendableAPI, ch address.Address) (map[uint64]*paych0.SignedVoucher, error) {
+func BestSpendableByLane(ctx context.Context, api BestSpendableAPI, ch address.Address) (map[uint64]*paych.SignedVoucher, error) {
 	vouchers, err := api.PaychVoucherList(ctx, ch)
 	if err != nil {
 		return nil, err
 	}
 
-	bestByLane := make(map[uint64]*paych0.SignedVoucher)
+	bestByLane := make(map[uint64]*paych.SignedVoucher)
 	for _, voucher := range vouchers {
 		spendable, err := api.PaychVoucherCheckSpendable(ctx, ch, voucher, nil, nil)
 		if err != nil {
diff --git a/storage/wdpost_run.go b/storage/wdpost_run.go
index 65dbd6e59..6aa3d5188 100644
--- a/storage/wdpost_run.go
+++ b/storage/wdpost_run.go
@@ -327,17 +327,22 @@ func (s *WindowPoStScheduler) checkNextFaults(ctx context.Context, dlIdx uint64,
 	}
 
 	for partIdx, partition := range partitions {
-		good, err := s.checkSectors(ctx, partition.ActiveSectors)
+		nonFaulty, err := bitfield.SubtractBitField(partition.LiveSectors, partition.FaultySectors)
+		if err != nil {
+			return nil, nil, xerrors.Errorf("determining non faulty sectors: %w", err)
+		}
+
+		good, err := s.checkSectors(ctx, nonFaulty)
 		if err != nil {
 			return nil, nil, xerrors.Errorf("checking sectors: %w", err)
 		}
 
-		faulty, err := bitfield.SubtractBitField(partition.ActiveSectors, good)
+		newFaulty, err := bitfield.SubtractBitField(nonFaulty, good)
 		if err != nil {
 			return nil, nil, xerrors.Errorf("calculating faulty sector set: %w", err)
 		}
 
-		c, err := faulty.Count()
+		c, err := newFaulty.Count()
 		if err != nil {
 			return nil, nil, xerrors.Errorf("counting faulty sectors: %w", err)
 		}
@@ -351,7 +356,7 @@ func (s *WindowPoStScheduler) checkNextFaults(ctx context.Context, dlIdx uint64,
 		params.Faults = append(params.Faults, miner.FaultDeclaration{
 			Deadline:  dlIdx,
 			Partition: uint64(partIdx),
-			Sectors:   faulty,
+			Sectors:   newFaulty,
 		})
 	}
 
@@ -509,7 +514,11 @@ func (s *WindowPoStScheduler) runPost(ctx context.Context, di dline.Info, ts *ty
 			var sinfos []proof.SectorInfo
 			for partIdx, partition := range batch {
 				// TODO: Can do this in parallel
-				toProve, err := bitfield.MergeBitFields(partition.ActiveSectors, partition.RecoveringSectors)
+				toProve, err := bitfield.SubtractBitField(partition.LiveSectors, partition.FaultySectors)
+				if err != nil {
+					return nil, xerrors.Errorf("removing faults from set of sectors to prove: %w", err)
+				}
+				toProve, err = bitfield.MergeBitFields(toProve, partition.RecoveringSectors)
 				if err != nil {
 					return nil, xerrors.Errorf("adding recoveries to set of sectors to prove: %w", err)
 				}