diff --git a/chain/gen/gen.go b/chain/gen/gen.go
index 5cee19efb..fe5d6221d 100644
--- a/chain/gen/gen.go
+++ b/chain/gen/gen.go
@@ -20,7 +20,6 @@ import (
 	"github.com/filecoin-project/go-lotus/chain/store"
 	"github.com/filecoin-project/go-lotus/chain/types"
 	"github.com/filecoin-project/go-lotus/chain/wallet"
-	"github.com/filecoin-project/go-lotus/lib/vdf"
 	"github.com/filecoin-project/go-lotus/node/repo"
 
 	block "github.com/ipfs/go-block-format"
@@ -213,20 +212,13 @@ func (cg *ChainGen) nextBlockProof(ctx context.Context, pts *types.TipSet, m add
 		return nil, nil, err
 	}
 
-	vrfout, err := ComputeVRF(ctx, cg.w.Sign, worker, lastTicket.VDFResult)
-	if err != nil {
-		return nil, nil, err
-	}
-
-	out, proof, err := vdf.Run(vrfout)
+	vrfout, err := ComputeVRF(ctx, cg.w.Sign, worker, lastTicket.VRFProof)
 	if err != nil {
 		return nil, nil, err
 	}
 
 	tick := &types.Ticket{
-		VRFProof:  vrfout,
-		VDFProof:  proof,
-		VDFResult: out,
+		VRFProof: vrfout,
 	}
 
 	win, eproof, err := IsRoundWinner(ctx, pts, append(ticks, tick), m, &mca{w: cg.w, sm: cg.sm})
diff --git a/chain/gen/utils.go b/chain/gen/utils.go
index af42e4c2e..f6784962e 100644
--- a/chain/gen/utils.go
+++ b/chain/gen/utils.go
@@ -329,9 +329,7 @@ func MakeGenesisBlock(bs bstore.Blockstore, balances map[address.Address]types.B
 	log.Infof("Empty Genesis root: %s", emptyroot)
 
 	genesisticket := &types.Ticket{
-		VRFProof:  []byte("vrf proof"),
-		VDFResult: []byte("i am a vdf result"),
-		VDFProof:  []byte("vdf proof"),
+		VRFProof: []byte("vrf proof"),
 	}
 
 	b := &types.BlockHeader{
diff --git a/chain/store/store.go b/chain/store/store.go
index 33c139913..bbda0d145 100644
--- a/chain/store/store.go
+++ b/chain/store/store.go
@@ -743,7 +743,7 @@ func (cs *ChainStore) GetRandomness(ctx context.Context, blks []cid.Cid, tickets
 
 		t := tickets[lt-(1+lb)]
 
-		return t.VDFResult, nil
+		return t.VRFProof, nil
 	}
 
 	nv := lb - lt
@@ -758,7 +758,7 @@ func (cs *ChainStore) GetRandomness(ctx context.Context, blks []cid.Cid, tickets
 		lt := int64(len(mtb.Tickets))
 		if nv < lt {
 			t := mtb.Tickets[lt-(1+nv)]
-			return t.VDFResult, nil
+			return t.VRFProof, nil
 		}
 
 		nv -= lt
@@ -769,7 +769,7 @@ func (cs *ChainStore) GetRandomness(ctx context.Context, blks []cid.Cid, tickets
 
 			t := mtb.Tickets[0]
 
-			rval := t.VDFResult
+			rval := t.VRFProof
 			for i := int64(0); i < nv; i++ {
 				h := sha256.Sum256(rval)
 				rval = h[:]
diff --git a/chain/sync.go b/chain/sync.go
index cd288d7ee..054c46c59 100644
--- a/chain/sync.go
+++ b/chain/sync.go
@@ -14,7 +14,6 @@ import (
 	"github.com/filecoin-project/go-lotus/chain/stmgr"
 	"github.com/filecoin-project/go-lotus/chain/store"
 	"github.com/filecoin-project/go-lotus/chain/types"
-	"github.com/filecoin-project/go-lotus/lib/vdf"
 
 	amt "github.com/filecoin-project/go-amt-ipld"
 	"github.com/ipfs/go-cid"
@@ -405,15 +404,11 @@ func (syncer *Syncer) validateTickets(ctx context.Context, mworker address.Addre
 			Data: next.VRFProof,
 		}
 
-		if err := sig.Verify(mworker, cur.VDFResult); err != nil {
+		// TODO: ticket signatures should also include miner address
+		if err := sig.Verify(mworker, cur.VRFProof); err != nil {
 			return xerrors.Errorf("invalid ticket, VRFProof invalid: %w", err)
 		}
 
-		// now verify the VDF
-		if err := vdf.Verify(next.VRFProof, next.VDFResult, next.VDFProof); err != nil {
-			return xerrors.Errorf("ticket %d had invalid VDF: %w", err)
-		}
-
 		cur = next
 	}
 
diff --git a/chain/types/blockheader.go b/chain/types/blockheader.go
index 55b09f870..f1003ed07 100644
--- a/chain/types/blockheader.go
+++ b/chain/types/blockheader.go
@@ -14,9 +14,7 @@ import (
 )
 
 type Ticket struct {
-	VRFProof  []byte
-	VDFResult []byte
-	VDFProof  []byte
+	VRFProof []byte
 }
 
 type ElectionProof []byte
@@ -176,5 +174,5 @@ func PowerCmp(eproof ElectionProof, mpow, totpow BigInt) bool {
 }
 
 func (t *Ticket) Equals(ot *Ticket) bool {
-	return bytes.Equal(t.VDFResult, ot.VDFResult)
+	return bytes.Equal(t.VRFProof, ot.VRFProof)
 }
diff --git a/chain/types/blockheader_test.go b/chain/types/blockheader_test.go
index fadac1698..6af560423 100644
--- a/chain/types/blockheader_test.go
+++ b/chain/types/blockheader_test.go
@@ -27,9 +27,7 @@ func testBlockHeader(t testing.TB) *BlockHeader {
 		ElectionProof: []byte("cats won the election"),
 		Tickets: []*Ticket{
 			&Ticket{
-				VRFProof:  []byte("vrf proof"),
-				VDFResult: []byte("vdf result"),
-				VDFProof:  []byte("vrf proof"),
+				VRFProof: []byte("vrf proof"),
 			},
 		},
 		Parents:               []cid.Cid{c, c},
diff --git a/chain/types/cbor_gen.go b/chain/types/cbor_gen.go
index 5841abf03..bad374f1b 100644
--- a/chain/types/cbor_gen.go
+++ b/chain/types/cbor_gen.go
@@ -5,7 +5,7 @@ import (
 	"io"
 	"math"
 
-	cid "github.com/ipfs/go-cid"
+	"github.com/ipfs/go-cid"
 	cbg "github.com/whyrusleeping/cbor-gen"
 	xerrors "golang.org/x/xerrors"
 )
@@ -284,7 +284,7 @@ func (t *Ticket) MarshalCBOR(w io.Writer) error {
 		_, err := w.Write(cbg.CborNull)
 		return err
 	}
-	if _, err := w.Write([]byte{131}); err != nil {
+	if _, err := w.Write([]byte{129}); err != nil {
 		return err
 	}
 
@@ -295,22 +295,6 @@ func (t *Ticket) MarshalCBOR(w io.Writer) error {
 	if _, err := w.Write(t.VRFProof); err != nil {
 		return err
 	}
-
-	// t.t.VDFResult ([]uint8)
-	if _, err := w.Write(cbg.CborEncodeMajorType(cbg.MajByteString, uint64(len(t.VDFResult)))); err != nil {
-		return err
-	}
-	if _, err := w.Write(t.VDFResult); err != nil {
-		return err
-	}
-
-	// t.t.VDFProof ([]uint8)
-	if _, err := w.Write(cbg.CborEncodeMajorType(cbg.MajByteString, uint64(len(t.VDFProof)))); err != nil {
-		return err
-	}
-	if _, err := w.Write(t.VDFProof); err != nil {
-		return err
-	}
 	return nil
 }
 
@@ -325,7 +309,7 @@ func (t *Ticket) UnmarshalCBOR(r io.Reader) error {
 		return fmt.Errorf("cbor input should be of type array")
 	}
 
-	if extra != 3 {
+	if extra != 1 {
 		return fmt.Errorf("cbor input had wrong number of fields")
 	}
 
@@ -346,40 +330,6 @@ func (t *Ticket) UnmarshalCBOR(r io.Reader) error {
 	if _, err := io.ReadFull(br, t.VRFProof); err != nil {
 		return err
 	}
-	// t.t.VDFResult ([]uint8)
-
-	maj, extra, err = cbg.CborReadHeader(br)
-	if err != nil {
-		return err
-	}
-	if extra > 8192 {
-		return fmt.Errorf("t.VDFResult: array too large (%d)", extra)
-	}
-
-	if maj != cbg.MajByteString {
-		return fmt.Errorf("expected byte array")
-	}
-	t.VDFResult = make([]byte, extra)
-	if _, err := io.ReadFull(br, t.VDFResult); err != nil {
-		return err
-	}
-	// t.t.VDFProof ([]uint8)
-
-	maj, extra, err = cbg.CborReadHeader(br)
-	if err != nil {
-		return err
-	}
-	if extra > 8192 {
-		return fmt.Errorf("t.VDFProof: array too large (%d)", extra)
-	}
-
-	if maj != cbg.MajByteString {
-		return fmt.Errorf("expected byte array")
-	}
-	t.VDFProof = make([]byte, extra)
-	if _, err := io.ReadFull(br, t.VDFProof); err != nil {
-		return err
-	}
 	return nil
 }
 
diff --git a/chain/types/tipset.go b/chain/types/tipset.go
index 2197b2d3f..979f59290 100644
--- a/chain/types/tipset.go
+++ b/chain/types/tipset.go
@@ -125,7 +125,7 @@ func (ts *TipSet) Equals(ots *TipSet) bool {
 }
 
 func (t *Ticket) Less(o *Ticket) bool {
-	return bytes.Compare(t.VDFResult, o.VDFResult) < 0
+	return bytes.Compare(t.VRFProof, o.VRFProof) < 0
 }
 
 func (ts *TipSet) MinTicket() *Ticket {
diff --git a/lib/vdf/vdf.go b/lib/vdf/vdf.go
deleted file mode 100644
index 98590be8e..000000000
--- a/lib/vdf/vdf.go
+++ /dev/null
@@ -1,28 +0,0 @@
-package vdf
-
-import (
-	"bytes"
-	"crypto/sha256"
-	"fmt"
-)
-
-func Run(input []byte) ([]byte, []byte, error) {
-	h := sha256.Sum256(input)
-	// TODO: THIS IS A FAKE VDF. THE SPEC IS UNCLEAR ON WHAT TO REALLY DO HERE
-	return h[:], []byte("proof"), nil
-}
-
-func Verify(input []byte, out []byte, proof []byte) error {
-	// this is a fake VDF
-	h := sha256.Sum256(input)
-
-	if !bytes.Equal(h[:], out) {
-		return fmt.Errorf("vdf output incorrect")
-	}
-
-	if !bytes.Equal(proof, []byte("proof")) {
-		return fmt.Errorf("vdf proof failed to validate")
-	}
-
-	return nil
-}
diff --git a/miner/miner.go b/miner/miner.go
index df47f3f14..84c779a70 100644
--- a/miner/miner.go
+++ b/miner/miner.go
@@ -10,7 +10,6 @@ import (
 	"github.com/filecoin-project/go-lotus/chain/address"
 	"github.com/filecoin-project/go-lotus/chain/gen"
 	"github.com/filecoin-project/go-lotus/chain/types"
-	"github.com/filecoin-project/go-lotus/lib/vdf"
 	"github.com/filecoin-project/go-lotus/node/impl/full"
 
 	logging "github.com/ipfs/go-log"
@@ -22,7 +21,7 @@ import (
 
 var log = logging.Logger("miner")
 
-type vdfFunc func(ctx context.Context, input []byte) ([]byte, []byte, error)
+type waitFunc func(ctx context.Context) error
 
 type api struct {
 	fx.In
@@ -36,9 +35,11 @@ type api struct {
 func NewMiner(api api) *Miner {
 	return &Miner{
 		api: api,
-
-		// time between blocks, network parameter
-		runVDF: delayVDF(build.BlockDelay * time.Second),
+		waitFunc: func(ctx context.Context) error {
+			// Wait around for half the block time in case other parents come in
+			time.Sleep(build.BlockDelay * time.Second / 2)
+			return nil
+		},
 	}
 }
 
@@ -50,7 +51,7 @@ type Miner struct {
 	stop      chan struct{}
 	stopping  chan struct{}
 
-	runVDF vdfFunc
+	waitFunc waitFunc
 
 	lastWork *MiningBase
 }
@@ -144,6 +145,10 @@ func (m *Miner) mine(ctx context.Context) {
 			return
 		default:
 		}
+		if err := m.waitFunc(ctx); err != nil {
+			log.Error(err)
+			return
+		}
 
 		base, err := m.GetBestMiningCandidate()
 		if err != nil {
@@ -159,6 +164,11 @@ func (m *Miner) mine(ctx context.Context) {
 			continue
 		}
 
+		btime := time.Unix(int64(b.Header.Timestamp), 0)
+		if time.Now().Before(btime) {
+			time.Sleep(time.Until(btime))
+		}
+
 		if b != nil {
 			if err := m.api.ChainSubmitBlock(ctx, b); err != nil {
 				log.Errorf("failed to submit newly mined block: %s", err)
@@ -255,18 +265,6 @@ func (m *Miner) getMinerWorker(ctx context.Context, addr address.Address, ts *ty
 	return w, nil
 }
 
-func delayVDF(delay time.Duration) func(ctx context.Context, input []byte) ([]byte, []byte, error) {
-	return func(ctx context.Context, input []byte) ([]byte, []byte, error) {
-		select {
-		case <-ctx.Done():
-			return nil, nil, ctx.Err()
-		case <-time.After(delay):
-		}
-
-		return vdf.Run(input)
-	}
-}
-
 func (m *Miner) scratchTicket(ctx context.Context, base *MiningBase) (*types.Ticket, error) {
 	var lastTicket *types.Ticket
 	if len(base.tickets) > 0 {
@@ -275,20 +273,13 @@ func (m *Miner) scratchTicket(ctx context.Context, base *MiningBase) (*types.Tic
 		lastTicket = base.ts.MinTicket()
 	}
 
-	vrfOut, err := m.computeVRF(ctx, lastTicket.VDFResult)
-	if err != nil {
-		return nil, err
-	}
-
-	res, proof, err := m.runVDF(ctx, vrfOut)
+	vrfOut, err := m.computeVRF(ctx, lastTicket.VRFProof)
 	if err != nil {
 		return nil, err
 	}
 
 	return &types.Ticket{
-		VRFProof:  vrfOut,
-		VDFResult: res,
-		VDFProof:  proof,
+		VRFProof: vrfOut,
 	}, nil
 }
 
@@ -304,7 +295,7 @@ func (m *Miner) createBlock(base *MiningBase, ticket *types.Ticket, proof types.
 		return nil, xerrors.Errorf("message filtering failed: %w", err)
 	}
 
-	uts := time.Now().Unix() // TODO: put smallest valid timestamp
+	uts := base.ts.MinTimestamp() + uint64(build.BlockDelay*(len(base.tickets)+1))
 
 	// why even return this? that api call could just submit it for us
 	return m.api.MinerCreateBlock(context.TODO(), m.addresses[0], base.ts, append(base.tickets, ticket), proof, msgs, uint64(uts))
diff --git a/miner/testminer.go b/miner/testminer.go
index 241f9ffa8..6adf02266 100644
--- a/miner/testminer.go
+++ b/miner/testminer.go
@@ -2,27 +2,25 @@ package miner
 
 import (
 	"context"
-
-	"github.com/filecoin-project/go-lotus/lib/vdf"
 )
 
 func NewTestMiner(nextCh <-chan struct{}) func(api api) *Miner {
 	return func(api api) *Miner {
 		return &Miner{
-			api:    api,
-			runVDF: chanVDF(nextCh),
+			api:      api,
+			waitFunc: chanWaiter(nextCh),
 		}
 	}
 }
 
-func chanVDF(next <-chan struct{}) func(ctx context.Context, input []byte) ([]byte, []byte, error) {
-	return func(ctx context.Context, input []byte) ([]byte, []byte, error) {
+func chanWaiter(next <-chan struct{}) func(ctx context.Context) error {
+	return func(ctx context.Context) error {
 		select {
 		case <-ctx.Done():
-			return nil, nil, ctx.Err()
+			return ctx.Err()
 		case <-next:
 		}
 
-		return vdf.Run(input)
+		return nil
 	}
 }