diff --git a/.changeset/add_support_for_block_pruning.md b/.changeset/add_support_for_block_pruning.md
new file mode 100644
index 0000000..95fe1ad
--- /dev/null
+++ b/.changeset/add_support_for_block_pruning.md
@@ -0,0 +1,7 @@
+---
+default: minor
+---
+
+# Add support for block pruning
+
+The chain manager can now automatically delete blocks after a configurable number of confirmations. Note that this does not apply retroactively.
diff --git a/chain/db.go b/chain/db.go
index 9f1eda0..466acfa 100644
--- a/chain/db.go
+++ b/chain/db.go
@@ -13,43 +13,32 @@ import (
 )
 
 type supplementedBlock struct {
-	Block      types.Block
+	Header     *types.BlockHeader
+	Block      *types.Block
 	Supplement *consensus.V1BlockSupplement
 }
 
 func (sb supplementedBlock) EncodeTo(e *types.Encoder) {
-	e.WriteUint8(2)
-	(types.V2Block)(sb.Block).EncodeTo(e)
-	e.WriteBool(sb.Supplement != nil)
-	if sb.Supplement != nil {
-		sb.Supplement.EncodeTo(e)
-	}
+	e.WriteUint8(3)
+	types.EncodePtr(e, sb.Header)
+	types.EncodePtr(e, (*types.V2Block)(sb.Block))
+	types.EncodePtr(e, sb.Supplement)
 }
 
 func (sb *supplementedBlock) DecodeFrom(d *types.Decoder) {
-	if v := d.ReadUint8(); v != 2 {
-		d.SetErr(fmt.Errorf("incompatible version (%d)", v))
-	}
-	(*types.V2Block)(&sb.Block).DecodeFrom(d)
-	if d.ReadBool() {
-		sb.Supplement = new(consensus.V1BlockSupplement)
-		sb.Supplement.DecodeFrom(d)
-	}
-}
-
-// helper type for decoding just the header information from a block
-type supplementedHeader struct {
-	ParentID  types.BlockID
-	Timestamp time.Time
-}
-
-func (sh *supplementedHeader) DecodeFrom(d *types.Decoder) {
-	if v := d.ReadUint8(); v != 2 {
+	switch v := d.ReadUint8(); v {
+	case 2:
+		sb.Header = nil
+		sb.Block = new(types.Block)
+		(*types.V2Block)(sb.Block).DecodeFrom(d)
+		types.DecodePtr(d, &sb.Supplement)
+	case 3:
+		types.DecodePtr(d, &sb.Header)
+		types.DecodePtrCast[types.V2Block](d, &sb.Block)
+		types.DecodePtr(d, &sb.Supplement)
+	default:
 		d.SetErr(fmt.Errorf("incompatible version (%d)", v))
 	}
-	sh.ParentID.DecodeFrom(d)
-	_ = d.ReadUint64() // nonce
-	sh.Timestamp = d.ReadTime()
 }
 
 type versionedState struct {
@@ -304,21 +293,62 @@ func (db *DBStore) putState(cs consensus.State) {
 	db.bucket(bStates).put(cs.Index.ID[:], versionedState{cs})
 }
 
-func (db *DBStore) getBlock(id types.BlockID) (b types.Block, bs *consensus.V1BlockSupplement, _ bool) {
+func (db *DBStore) getBlock(id types.BlockID) (bh types.BlockHeader, b *types.Block, bs *consensus.V1BlockSupplement, _ bool) {
 	var sb supplementedBlock
 	ok := db.bucket(bBlocks).get(id[:], &sb)
-	return sb.Block, sb.Supplement, ok
+	if sb.Header == nil {
+		sb.Header = new(types.BlockHeader)
+		*sb.Header = sb.Block.Header()
+	}
+	return *sb.Header, sb.Block, sb.Supplement, ok
 }
 
-func (db *DBStore) putBlock(b types.Block, bs *consensus.V1BlockSupplement) {
-	id := b.ID()
-	db.bucket(bBlocks).put(id[:], supplementedBlock{b, bs})
+func (db *DBStore) putBlock(bh types.BlockHeader, b *types.Block, bs *consensus.V1BlockSupplement) {
+	id := bh.ID()
+	db.bucket(bBlocks).put(id[:], supplementedBlock{&bh, b, bs})
 }
 
-func (db *DBStore) getBlockHeader(id types.BlockID) (parentID types.BlockID, timestamp time.Time, _ bool) {
-	var sh supplementedHeader
-	ok := db.bucket(bBlocks).get(id[:], &sh)
-	return sh.ParentID, sh.Timestamp, ok
+func (db *DBStore) getAncestorInfo(id types.BlockID) (parentID types.BlockID, timestamp time.Time, ok bool) {
+	ok = db.bucket(bBlocks).get(id[:], types.DecoderFunc(func(d *types.Decoder) {
+		v := d.ReadUint8()
+		if v != 2 && v != 3 {
+			d.SetErr(fmt.Errorf("incompatible version (%d)", v))
+		}
+		// kinda cursed; don't worry about it
+		if v == 3 {
+			if !d.ReadBool() {
+				d.ReadBool()
+			}
+		}
+		parentID.DecodeFrom(d)
+		_ = d.ReadUint64() // nonce
+		timestamp = d.ReadTime()
+	}))
+	return
+}
+
+func (db *DBStore) getBlockHeader(id types.BlockID) (bh types.BlockHeader, ok bool) {
+	ok = db.bucket(bBlocks).get(id[:], types.DecoderFunc(func(d *types.Decoder) {
+		v := d.ReadUint8()
+		if v != 2 && v != 3 {
+			d.SetErr(fmt.Errorf("incompatible version (%d)", v))
+			return
+		}
+		if v == 3 {
+			bhp := &bh
+			types.DecodePtr(d, &bhp)
+			if bhp != nil {
+				return
+			} else if !d.ReadBool() {
+				d.SetErr(errors.New("neither header nor block present"))
+				return
+			}
+		}
+		var b types.Block
+		(*types.V2Block)(&b).DecodeFrom(d)
+		bh = b.Header()
+	}))
+	return
 }
 
 func (db *DBStore) treeKey(row, col uint64) []byte {
@@ -628,9 +658,9 @@ func (db *DBStore) AncestorTimestamp(id types.BlockID) (t time.Time, ok bool) {
 			}
 			break
 		}
-		ancestorID, _, _ = db.getBlockHeader(ancestorID)
+		ancestorID, _, _ = db.getAncestorInfo(ancestorID)
 	}
-	_, t, ok = db.getBlockHeader(ancestorID)
+	_, t, ok = db.getAncestorInfo(ancestorID)
 	return
 }
 
@@ -646,12 +676,23 @@ func (db *DBStore) AddState(cs consensus.State) {
 
 // Block implements Store.
 func (db *DBStore) Block(id types.BlockID) (types.Block, *consensus.V1BlockSupplement, bool) {
-	return db.getBlock(id)
+	_, b, bs, ok := db.getBlock(id)
+	if !ok || b == nil {
+		return types.Block{}, nil, false
+	}
+	return *b, bs, ok
 }
 
 // AddBlock implements Store.
 func (db *DBStore) AddBlock(b types.Block, bs *consensus.V1BlockSupplement) {
-	db.putBlock(b, bs)
+	db.putBlock(b.Header(), &b, bs)
+}
+
+// PruneBlock implements Store.
+func (db *DBStore) PruneBlock(id types.BlockID) {
+	if bh, _, _, ok := db.getBlock(id); ok {
+		db.putBlock(bh, nil, nil)
+	}
 }
 
 func (db *DBStore) shouldFlush() bool {
@@ -743,7 +784,7 @@ func NewDBStore(db DB, n *consensus.Network, genesisBlock types.Block) (_ *DBSto
 		dbs.putState(genesisState)
 		bs := consensus.V1BlockSupplement{Transactions: make([]consensus.V1TransactionSupplement, len(genesisBlock.Transactions))}
 		cs, cau := consensus.ApplyBlock(genesisState, genesisBlock, bs, time.Time{})
-		dbs.putBlock(genesisBlock, &bs)
+		dbs.putBlock(genesisBlock.Header(), &genesisBlock, &bs)
 		dbs.putState(cs)
 		dbs.ApplyBlock(cs, cau)
 		if err := dbs.Flush(); err != nil {
diff --git a/chain/manager.go b/chain/manager.go
index 679b281..53e47da 100644
--- a/chain/manager.go
+++ b/chain/manager.go
@@ -45,6 +45,7 @@ type Store interface {
 
 	Block(id types.BlockID) (types.Block, *consensus.V1BlockSupplement, bool)
 	AddBlock(b types.Block, bs *consensus.V1BlockSupplement)
+	PruneBlock(id types.BlockID)
 	State(id types.BlockID) (consensus.State, bool)
 	AddState(cs consensus.State)
 	AncestorTimestamp(id types.BlockID) (time.Time, bool)
@@ -74,12 +75,15 @@ func blockAndChild(s Store, id types.BlockID) (types.Block, *consensus.V1BlockSu
 // A Manager tracks multiple blockchains and identifies the best valid
 // chain.
 type Manager struct {
-	log           *zap.Logger
 	store         Store
 	tipState      consensus.State
 	onReorg       map[[16]byte]func(types.ChainIndex)
 	invalidBlocks map[types.BlockID]error
 
+	// configuration options
+	log         *zap.Logger
+	pruneTarget uint64
+
 	txpool struct {
 		txns           []types.Transaction
 		v2txns         []types.V2Transaction
@@ -314,6 +318,12 @@ func (m *Manager) applyTip(index types.ChainIndex) error {
 	m.store.ApplyBlock(cs, cau)
 	m.applyPoolUpdate(cau, cs)
 	m.tipState = cs
+
+	if m.pruneTarget != 0 && cs.Index.Height > m.pruneTarget {
+		if index, ok := m.store.BestIndex(cs.Index.Height - m.pruneTarget); ok {
+			m.store.PruneBlock(index.ID)
+		}
+	}
 	return nil
 }
 
diff --git a/chain/options.go b/chain/options.go
index f7fa10a..05d5f6d 100644
--- a/chain/options.go
+++ b/chain/options.go
@@ -11,3 +11,10 @@ func WithLog(l *zap.Logger) ManagerOption {
 		m.log = l
 	}
 }
+
+// WithPruneTarget sets the target number of blocks to store.
+func WithPruneTarget(n uint64) ManagerOption {
+	return func(m *Manager) {
+		m.pruneTarget = n
+	}
+}
diff --git a/miner.go b/miner.go
index db4358a..e028d9d 100644
--- a/miner.go
+++ b/miner.go
@@ -10,15 +10,17 @@ import (
 
 // FindBlockNonce attempts to find a nonce for b that meets the PoW target.
 func FindBlockNonce(cs consensus.State, b *types.Block, timeout time.Duration) bool {
-	b.Nonce = 0
+	bh := b.Header()
+	bh.Nonce = 0
 	factor := cs.NonceFactor()
 	startBlock := time.Now()
-	for b.ID().CmpWork(cs.ChildTarget) < 0 {
-		b.Nonce += factor
+	for bh.ID().CmpWork(cs.ChildTarget) < 0 {
+		bh.Nonce += factor
 		if time.Since(startBlock) > timeout {
 			return false
 		}
 	}
+	b.Nonce = bh.Nonce
 	return true
 }
 
diff --git a/rhp/v4/rpc_test.go b/rhp/v4/rpc_test.go
index a869635..e264b1b 100644
--- a/rhp/v4/rpc_test.go
+++ b/rhp/v4/rpc_test.go
@@ -74,7 +74,7 @@ func startTestNode(tb testing.TB, n *consensus.Network, genesis types.Block) (*c
 	}
 	tb.Cleanup(func() { syncerListener.Close() })
 
-	s := syncer.New(syncerListener, cm, testutil.NewMemPeerStore(), gateway.Header{
+	s := syncer.New(syncerListener, cm, testutil.NewEphemeralPeerStore(), gateway.Header{
 		GenesisID:  genesis.ID(),
 		UniqueID:   gateway.GenerateUniqueID(),
 		NetAddress: "localhost:1234",
diff --git a/syncer/peer.go b/syncer/peer.go
index 45a6d81..de98c86 100644
--- a/syncer/peer.go
+++ b/syncer/peer.go
@@ -182,8 +182,8 @@ func (p *Peer) SendCheckpoint(index types.ChainIndex, timeout time.Duration) (ty
 }
 
 // RelayV2Header relays a v2 block header to the peer.
-func (p *Peer) RelayV2Header(h types.BlockHeader, timeout time.Duration) error {
-	return p.callRPC(&gateway.RPCRelayV2Header{Header: h}, timeout)
+func (p *Peer) RelayV2Header(bh types.BlockHeader, timeout time.Duration) error {
+	return p.callRPC(&gateway.RPCRelayV2Header{Header: bh}, timeout)
 }
 
 // RelayV2BlockOutline relays a v2 block outline to the peer.
diff --git a/syncer/syncer.go b/syncer/syncer.go
index f1ac29b..6778d79 100644
--- a/syncer/syncer.go
+++ b/syncer/syncer.go
@@ -533,9 +533,9 @@ func (s *Syncer) peerLoop(ctx context.Context) error {
 
 			ctx, cancel := context.WithTimeout(ctx, s.config.ConnectTimeout)
 			if _, err := s.Connect(ctx, p); err != nil {
-				log.Debug("connected to peer", zap.String("peer", p))
-			} else {
 				log.Debug("failed to connect to peer", zap.String("peer", p), zap.Error(err))
+			} else {
+				log.Debug("connected to peer", zap.String("peer", p))
 			}
 			cancel()
 			lastTried[p] = time.Now()
@@ -723,10 +723,12 @@ func (s *Syncer) Connect(ctx context.Context, addr string) (*Peer, error) {
 }
 
 // BroadcastHeader broadcasts a header to all peers.
-func (s *Syncer) BroadcastHeader(h types.BlockHeader) { s.relayHeader(h, nil) }
+func (s *Syncer) BroadcastHeader(bh types.BlockHeader) { s.relayHeader(bh, nil) }
 
 // BroadcastV2Header broadcasts a v2 header to all peers.
-func (s *Syncer) BroadcastV2Header(h types.BlockHeader) { s.relayV2Header(h, nil) }
+func (s *Syncer) BroadcastV2Header(bh types.BlockHeader) {
+	s.relayV2Header(bh, nil)
+}
 
 // BroadcastV2BlockOutline broadcasts a v2 block outline to all peers.
 func (s *Syncer) BroadcastV2BlockOutline(b gateway.V2BlockOutline) { s.relayV2BlockOutline(b, nil) }
diff --git a/syncer/syncer_test.go b/syncer/syncer_test.go
index d3551a0..eb5d673 100644
--- a/syncer/syncer_test.go
+++ b/syncer/syncer_test.go
@@ -42,7 +42,7 @@ func TestSyncer(t *testing.T) {
 	}
 	defer l2.Close()
 
-	s1 := syncer.New(l1, cm1, testutil.NewMemPeerStore(), gateway.Header{
+	s1 := syncer.New(l1, cm1, testutil.NewEphemeralPeerStore(), gateway.Header{
 		GenesisID:  genesis.ID(),
 		UniqueID:   gateway.GenerateUniqueID(),
 		NetAddress: l1.Addr().String(),
@@ -50,7 +50,7 @@ func TestSyncer(t *testing.T) {
 	defer s1.Close()
 	go s1.Run(context.Background())
 
-	s2 := syncer.New(l2, cm2, testutil.NewMemPeerStore(), gateway.Header{
+	s2 := syncer.New(l2, cm2, testutil.NewEphemeralPeerStore(), gateway.Header{
 		GenesisID:  genesis.ID(),
 		UniqueID:   gateway.GenerateUniqueID(),
 		NetAddress: l2.Addr().String(),
diff --git a/testutil/syncer.go b/testutil/syncer.go
index 1aba4f6..caa621a 100644
--- a/testutil/syncer.go
+++ b/testutil/syncer.go
@@ -7,15 +7,15 @@ import (
 	"go.sia.tech/coreutils/syncer"
 )
 
-// A MemPeerStore is an in-memory implementation of a PeerStore.
-type MemPeerStore struct {
+// A EphemeralPeerStore is an in-memory implementation of a PeerStore.
+type EphemeralPeerStore struct {
 	mu    sync.Mutex
 	peers map[string]syncer.PeerInfo
 }
 
 // AddPeer adds a peer to the store. If the peer already exists, nil should
 // be returned.
-func (ps *MemPeerStore) AddPeer(addr string) error {
+func (ps *EphemeralPeerStore) AddPeer(addr string) error {
 	ps.mu.Lock()
 	defer ps.mu.Unlock()
 	if _, ok := ps.peers[addr]; ok {
@@ -26,7 +26,7 @@ func (ps *MemPeerStore) AddPeer(addr string) error {
 }
 
 // Peers returns the set of known peers.
-func (ps *MemPeerStore) Peers() ([]syncer.PeerInfo, error) {
+func (ps *EphemeralPeerStore) Peers() ([]syncer.PeerInfo, error) {
 	ps.mu.Lock()
 	defer ps.mu.Unlock()
 	var peers []syncer.PeerInfo
@@ -38,7 +38,7 @@ func (ps *MemPeerStore) Peers() ([]syncer.PeerInfo, error) {
 
 // PeerInfo returns the metadata for the specified peer or ErrPeerNotFound
 // if the peer wasn't found in the store.
-func (ps *MemPeerStore) PeerInfo(addr string) (syncer.PeerInfo, error) {
+func (ps *EphemeralPeerStore) PeerInfo(addr string) (syncer.PeerInfo, error) {
 	ps.mu.Lock()
 	defer ps.mu.Unlock()
 	p, ok := ps.peers[addr]
@@ -50,7 +50,7 @@ func (ps *MemPeerStore) PeerInfo(addr string) (syncer.PeerInfo, error) {
 
 // UpdatePeerInfo updates the metadata for the specified peer. If the peer
 // is not found, the error should be ErrPeerNotFound.
-func (ps *MemPeerStore) UpdatePeerInfo(addr string, fn func(*syncer.PeerInfo)) error {
+func (ps *EphemeralPeerStore) UpdatePeerInfo(addr string, fn func(*syncer.PeerInfo)) error {
 	ps.mu.Lock()
 	defer ps.mu.Unlock()
 	p := ps.peers[addr]
@@ -61,18 +61,18 @@ func (ps *MemPeerStore) UpdatePeerInfo(addr string, fn func(*syncer.PeerInfo)) e
 
 // Ban temporarily bans one or more IPs. The addr should either be a single
 // IP with port (e.g. 1.2.3.4:5678) or a CIDR subnet (e.g. 1.2.3.4/16).
-func (ps *MemPeerStore) Ban(addr string, duration time.Duration, reason string) error {
+func (ps *EphemeralPeerStore) Ban(addr string, duration time.Duration, reason string) error {
 	return nil
 }
 
 // Banned returns false
-func (ps *MemPeerStore) Banned(addr string) (bool, error) { return false, nil }
+func (ps *EphemeralPeerStore) Banned(addr string) (bool, error) { return false, nil }
 
-var _ syncer.PeerStore = (*MemPeerStore)(nil)
+var _ syncer.PeerStore = (*EphemeralPeerStore)(nil)
 
-// NewMemPeerStore returns a new MemPeerStore.
-func NewMemPeerStore() *MemPeerStore {
-	return &MemPeerStore{
+// NewEphemeralPeerStore returns a new EphemeralPeerStore.
+func NewEphemeralPeerStore() *EphemeralPeerStore {
+	return &EphemeralPeerStore{
 		peers: make(map[string]syncer.PeerInfo),
 	}
 }