diff --git a/chain/actors/builtin/paych/paych.go b/chain/actors/builtin/paych/paych.go
index f462de6fd..20c7a74b7 100644
--- a/chain/actors/builtin/paych/paych.go
+++ b/chain/actors/builtin/paych/paych.go
@@ -1,6 +1,8 @@
 package paych
 
 import (
+	"encoding/base64"
+
 	"golang.org/x/xerrors"
 
 	"github.com/filecoin-project/go-address"
@@ -8,6 +10,7 @@ import (
 	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"
@@ -68,3 +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/stmgr/forks.go b/chain/stmgr/forks.go
index 252b731d7..9561e5ed9 100644
--- a/chain/stmgr/forks.go
+++ b/chain/stmgr/forks.go
@@ -6,31 +6,27 @@ 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/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"
+
 	"github.com/filecoin-project/lotus/build"
+	"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){
diff --git a/chain/store/store.go b/chain/store/store.go
index 6c93db7a0..ab732413b 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"
@@ -747,7 +749,8 @@ 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)
 	}
@@ -940,7 +943,8 @@ 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 c6e0c8b80..eb17b078d 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"
@@ -374,9 +375,10 @@ 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 9e098a57e..6abe43567 100644
--- a/chain/sync.go
+++ b/chain/sync.go
@@ -33,9 +33,10 @@ 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 +456,10 @@ 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)
@@ -1092,9 +1094,9 @@ 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)
@@ -1106,7 +1108,7 @@ 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/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/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/extern/storage-sealing/states_failed.go b/extern/storage-sealing/states_failed.go
index b026e70f9..63e64ca1b 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/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/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/impl/full/chain.go b/node/impl/full/chain.go
index ea715c66a..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))
diff --git a/paychmgr/manager.go b/paychmgr/manager.go
index d9c568cbe..7ef1264c5 100644
--- a/paychmgr/manager.go
+++ b/paychmgr/manager.go
@@ -12,7 +12,6 @@ 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/lotus/api"
 	"github.com/filecoin-project/lotus/chain/actors/adt"
@@ -221,7 +220,7 @@ 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 +232,7 @@ 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 {
@@ -245,7 +244,7 @@ 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) {
 	ca, err := pm.accessorByAddress(ch)
 	if err != nil {
 		return false, err
@@ -256,7 +255,7 @@ func (pm *Manager) CheckVoucherSpendable(ctx context.Context, ch address.Address
 
 // 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) {
 	ca, err := pm.accessorByAddress(ch)
 	if err != nil {
 		return types.NewInt(0), err
@@ -267,7 +266,7 @@ func (pm *Manager) AddVoucherOutbound(ctx context.Context, ch address.Address, s
 // 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) {
 	// Get an accessor for the channel, creating it from state if necessary
 	ca, err := pm.inboundChannelAccessor(ctx, ch)
 	if err != nil {
@@ -336,7 +335,7 @@ 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) {
 	ca, err := pm.accessorByAddress(ch)
 	if err != nil {
 		return cid.Undef, err
diff --git a/paychmgr/paych.go b/paychmgr/paych.go
index f856b9890..ba96c5e40 100644
--- a/paychmgr/paych.go
+++ b/paychmgr/paych.go
@@ -103,7 +103,7 @@ 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()
 
@@ -162,14 +162,14 @@ 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)
 	}
@@ -272,7 +272,7 @@ 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, proof []byte) (bool, error) {
 	ca.lk.Lock()
 	defer ca.lk.Unlock()
 
@@ -346,14 +346,14 @@ 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, proof []byte, minDelta types.BigInt) (types.BigInt, error) {
 	ca.lk.Lock()
 	defer ca.lk.Unlock()
 
 	return ca.addVoucherUnlocked(ctx, ch, sv, proof, 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, proof []byte, minDelta types.BigInt) (types.BigInt, error) {
 	ci, err := ca.store.ByAddress(ch)
 	if err != nil {
 		return types.BigInt{}, err
@@ -420,7 +420,7 @@ 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, proof []byte) (cid.Cid, error) {
 	ca.lk.Lock()
 	defer ca.lk.Unlock()
 
@@ -461,6 +461,10 @@ func (ca *channelAccessor) submitVoucher(ctx context.Context, ch address.Address
 		}
 	}
 
+	// TODO: ActorUpgrade
+	// The "proof" field is going away. We will need to abstract over the
+	// network version here.
+	// Alternatively, we'd need to support the "old" method on-chain.
 	enc, err := actors.SerializeParams(&paych0.UpdateChannelStateParams{
 		Sv:     *sv,
 		Secret: secret,
@@ -572,7 +576,7 @@ func (ca *channelAccessor) laneState(ctx context.Context, state paych.State, ch
 }
 
 // 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")
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/store.go b/paychmgr/store.go
index 23916669e..dbd663832 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"
 )
 
@@ -49,7 +48,7 @@ const (
 )
 
 type VoucherInfo struct {
-	Voucher   *paych0.SignedVoucher
+	Voucher   *paych.SignedVoucher
 	Proof     []byte
 	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 {