Support forfeit with CHECKLOCKTIMEVERIFY (#389)

* explicit Timelock struct * support & test CLTV forfeit path * fix wasm pkg * fix wasm * fix liquid GetCurrentBlockTime * cleaning * move esplora URL check
2025-12-17 04:04:21 +01:00 · 2024-11-28 14:51:06 +01:00
parent a4ae439341
commit 02542c3634
51 changed files with 1007 additions and 257 deletions
--- a/common/bip68.go
+++ b/common/bip68.go
@@ -14,31 +14,68 @@ const (
 	SECONDS_MOD                    = 1 << SEQUENCE_LOCKTIME_GRANULARITY
 	SECONDS_MAX                    = SEQUENCE_LOCKTIME_MASK << SEQUENCE_LOCKTIME_GRANULARITY
 	SEQUENCE_LOCKTIME_DISABLE_FLAG = 1 << 31
+
+	SECONDS_PER_BLOCK = 10 * 60 // 10 minutes
 )

-func closerToModulo512(x uint) uint {
-	return x - (x % 512)
+type LocktimeType uint
+
+const (
+	LocktimeTypeSecond LocktimeType = iota
+	LocktimeTypeBlock
+)
+
+// Locktime represents a BIP68 relative timelock value.
+// This struct is comparable and can be used as a map key.
+type Locktime struct {
+	Type  LocktimeType
+	Value uint32
 }

-func BIP68Sequence(locktime uint) (uint32, error) {
-	isSeconds := locktime >= 512
+func (l Locktime) Seconds() int64 {
+	if l.Type == LocktimeTypeBlock {
+		return int64(l.Value) * SECONDS_PER_BLOCK
+	}
+	return int64(l.Value)
+}
+
+func (l Locktime) Compare(other Locktime) int {
+	val := l.Seconds()
+	otherVal := other.Seconds()
+
+	if val == otherVal {
+		return 0
+	}
+	if val < otherVal {
+		return -1
+	}
+	return 1
+}
+
+// LessThan returns true if this locktime is less than the other locktime
+func (l Locktime) LessThan(other Locktime) bool {
+	return l.Compare(other) < 0
+}
+
+func BIP68Sequence(locktime Locktime) (uint32, error) {
+	value := locktime.Value
+	isSeconds := locktime.Type == LocktimeTypeSecond
 	if isSeconds {
-		locktime = closerToModulo512(locktime)
-		if locktime > SECONDS_MAX {
+		if value > SECONDS_MAX {
 			return 0, fmt.Errorf("seconds too large, max is %d", SECONDS_MAX)
 		}
-		if locktime%SECONDS_MOD != 0 {
+		if value%SECONDS_MOD != 0 {
 			return 0, fmt.Errorf("seconds must be a multiple of %d", SECONDS_MOD)
 		}
 	}

-	return blockchain.LockTimeToSequence(isSeconds, uint32(locktime)), nil
+	return blockchain.LockTimeToSequence(isSeconds, value), nil
 }

-func BIP68DecodeSequence(sequence []byte) (uint, error) {
+func BIP68DecodeSequence(sequence []byte) (*Locktime, error) {
 	scriptNumber, err := txscript.MakeScriptNum(sequence, true, len(sequence))
 	if err != nil {
-		return 0, err
+		return nil, err
 	}

 	if scriptNumber >= txscript.OP_1 && scriptNumber <= txscript.OP_16 {
@@ -48,12 +85,12 @@ func BIP68DecodeSequence(sequence []byte) (uint, error) {
 	asNumber := int64(scriptNumber)

 	if asNumber&SEQUENCE_LOCKTIME_DISABLE_FLAG != 0 {
-		return 0, fmt.Errorf("sequence is disabled")
+		return nil, fmt.Errorf("sequence is disabled")
 	}
 	if asNumber&SEQUENCE_LOCKTIME_TYPE_FLAG != 0 {
 		seconds := asNumber & SEQUENCE_LOCKTIME_MASK << SEQUENCE_LOCKTIME_GRANULARITY
-		return uint(seconds), nil
+		return &Locktime{Type: LocktimeTypeSecond, Value: uint32(seconds)}, nil
 	}

-	return uint(asNumber), nil
+	return &Locktime{Type: LocktimeTypeBlock, Value: uint32(asNumber)}, nil
 }
--- a/common/bitcointree/builder.go
+++ b/common/bitcointree/builder.go
@@ -18,7 +18,7 @@ import (
 // CraftSharedOutput returns the taproot script and the amount of the initial root output
 func CraftSharedOutput(
 	cosigners []*secp256k1.PublicKey, server *secp256k1.PublicKey, receivers []tree.VtxoLeaf,
-	feeSatsPerNode uint64, roundLifetime int64,
+	feeSatsPerNode uint64, roundLifetime common.Locktime,
 ) ([]byte, int64, error) {
 	aggregatedKey, _, err := createAggregatedKeyWithSweep(
 		cosigners, server, roundLifetime,
@@ -45,7 +45,7 @@ func CraftSharedOutput(
 // BuildVtxoTree creates all the tree's transactions
 func BuildVtxoTree(
 	initialInput *wire.OutPoint, cosigners []*secp256k1.PublicKey, server *secp256k1.PublicKey, receivers []tree.VtxoLeaf,
-	feeSatsPerNode uint64, roundLifetime int64,
+	feeSatsPerNode uint64, roundLifetime common.Locktime,
 ) (tree.VtxoTree, error) {
 	aggregatedKey, sweepTapLeaf, err := createAggregatedKeyWithSweep(
 		cosigners, server, roundLifetime,
@@ -280,11 +280,11 @@ func createRootNode(
 }

 func createAggregatedKeyWithSweep(
-	cosigners []*secp256k1.PublicKey, server *secp256k1.PublicKey, roundLifetime int64,
+	cosigners []*secp256k1.PublicKey, server *secp256k1.PublicKey, roundLifetime common.Locktime,
 ) (*musig2.AggregateKey, *psbt.TaprootTapLeafScript, error) {
 	sweepClosure := &tree.CSVSigClosure{
 		MultisigClosure: tree.MultisigClosure{PubKeys: []*secp256k1.PublicKey{server}},
-		Seconds:         uint(roundLifetime),
+		Locktime:        roundLifetime,
 	}

 	sweepScript, err := sweepClosure.Script()
--- a/common/bitcointree/musig2_test.go
+++ b/common/bitcointree/musig2_test.go
@@ -5,6 +5,7 @@ import (
 	"os"
 	"testing"

+	"github.com/ark-network/ark/common"
 	"github.com/ark-network/ark/common/bitcointree"
 	"github.com/ark-network/ark/common/tree"
 	"github.com/btcsuite/btcd/btcec/v2"
@@ -18,9 +19,10 @@ import (
 const (
 	minRelayFee = 1000
 	exitDelay   = 512
-	lifetime    = 1024
 )

+var lifetime = common.Locktime{Type: common.LocktimeTypeBlock, Value: 144}
+
 var testTxid, _ = chainhash.NewHashFromStr("49f8664acc899be91902f8ade781b7eeb9cbe22bdd9efbc36e56195de21bcd12")

 func TestRoundTripSignTree(t *testing.T) {
@@ -63,7 +65,7 @@ func TestRoundTripSignTree(t *testing.T) {

 		sweepClosure := &tree.CSVSigClosure{
 			MultisigClosure: tree.MultisigClosure{PubKeys: []*secp256k1.PublicKey{server.PubKey()}},
-			Seconds:         uint(lifetime),
+			Locktime:        lifetime,
 		}

 		sweepScript, err := sweepClosure.Script()
--- a/common/bitcointree/pending.go
+++ b/common/bitcointree/pending.go
@@ -12,7 +12,6 @@ import (
 func BuildRedeemTx(
 	vtxos []common.VtxoInput,
 	outputs []*wire.TxOut,
-	feeAmount int64,
 ) (string, error) {
 	if len(vtxos) <= 0 {
 		return "", fmt.Errorf("missing vtxos")
@@ -50,10 +49,6 @@ func BuildRedeemTx(
 		ins = append(ins, vtxo.Outpoint)
 	}

-	if feeAmount >= outputs[len(outputs)-1].Value {
-		return "", fmt.Errorf("redeem tx fee is higher than the amount of the change receiver")
-	}
-
 	sequences := make([]uint32, len(ins))
 	for i := range sequences {
 		sequences[i] = wire.MaxTxInSequenceNum
--- a/common/bitcointree/validation.go
+++ b/common/bitcointree/validation.go
@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"strings"

+	"github.com/ark-network/ark/common"
 	"github.com/ark-network/ark/common/tree"
 	"github.com/btcsuite/btcd/btcec/v2/schnorr"
 	"github.com/btcsuite/btcd/btcutil/psbt"
@@ -71,7 +72,7 @@ func UnspendableKey() *secp256k1.PublicKey {
 // - every control block and taproot output scripts
 // - input and output amounts
 func ValidateVtxoTree(
-	vtxoTree tree.VtxoTree, roundTx string, serverPubkey *secp256k1.PublicKey, roundLifetime int64,
+	vtxoTree tree.VtxoTree, roundTx string, serverPubkey *secp256k1.PublicKey, roundLifetime common.Locktime,
 ) error {
 	roundTransaction, err := psbt.NewFromRawBytes(strings.NewReader(roundTx), true)
 	if err != nil {
@@ -125,7 +126,7 @@ func ValidateVtxoTree(

 	sweepClosure := &tree.CSVSigClosure{
 		MultisigClosure: tree.MultisigClosure{PubKeys: []*secp256k1.PublicKey{serverPubkey}},
-		Seconds:         uint(roundLifetime),
+		Locktime:        roundLifetime,
 	}

 	sweepScript, err := sweepClosure.Script()
--- a/common/bitcointree/vtxo.go
+++ b/common/bitcointree/vtxo.go
@@ -10,7 +10,7 @@ import (
 	"github.com/decred/dcrd/dcrec/secp256k1/v4"
 )

-type VtxoScript common.VtxoScript[bitcoinTapTree, *tree.MultisigClosure, *tree.CSVSigClosure]
+type VtxoScript common.VtxoScript[bitcoinTapTree, tree.Closure]

 func ParseVtxoScript(scripts []string) (VtxoScript, error) {
 	types := []VtxoScript{
@@ -26,7 +26,7 @@ func ParseVtxoScript(scripts []string) (VtxoScript, error) {
 	return nil, fmt.Errorf("invalid vtxo scripts: %s", scripts)
 }

-func NewDefaultVtxoScript(owner, server *secp256k1.PublicKey, exitDelay uint) VtxoScript {
+func NewDefaultVtxoScript(owner, server *secp256k1.PublicKey, exitDelay common.Locktime) VtxoScript {
 	base := tree.NewDefaultVtxoScript(owner, server, exitDelay)

 	return &TapscriptsVtxoScript{*base}
--- a/common/descriptor/ark.go
+++ b/common/descriptor/ark.go
@@ -51,7 +51,7 @@ func ParseDefaultVtxoDescriptor(

 			if first, ok := andLeaf.First.(*Older); ok {
 				if second, ok := andLeaf.Second.(*PK); ok {
-					timeout = first.Timeout
+					timeout = uint(first.Locktime.Value)
 					keyBytes, err := hex.DecodeString(second.Key.Hex)
 					if err != nil {
 						return nil, nil, 0, err
--- a/common/descriptor/expression.go
+++ b/common/descriptor/expression.go
@@ -97,11 +97,11 @@ func (e *PK) Script(verify bool) (string, error) {
 }

 type Older struct {
-	Timeout uint
+	Locktime common.Locktime
 }

 func (e *Older) String() string {
-	return fmt.Sprintf("older(%d)", e.Timeout)
+	return fmt.Sprintf("older(%d)", e.Locktime.Value)
 }

 func (e *Older) Parse(policy string) error {
@@ -124,13 +124,13 @@ func (e *Older) Parse(policy string) error {
 		return ErrInvalidOlderPolicy
 	}

-	e.Timeout = uint(timeout)
+	e.Locktime = common.Locktime{Type: common.LocktimeTypeBlock, Value: uint32(timeout)}

 	return nil
 }

 func (e *Older) Script(bool) (string, error) {
-	sequence, err := common.BIP68Sequence(e.Timeout)
+	sequence, err := common.BIP68Sequence(e.Locktime)
 	if err != nil {
 		return "", err
 	}
--- a/common/descriptor/parser_test.go
+++ b/common/descriptor/parser_test.go
@@ -3,6 +3,7 @@ package descriptor_test
 import (
 	"testing"

+	"github.com/ark-network/ark/common"
 	"github.com/ark-network/ark/common/descriptor"
 	"github.com/stretchr/testify/require"
 )
@@ -53,7 +54,7 @@ func TestParseTaprootDescriptor(t *testing.T) {
 							},
 						},
 						Second: &descriptor.Older{
-							Timeout: 144,
+							Locktime: common.Locktime{Type: common.LocktimeTypeSecond, Value: 144},
 						},
 					},
 				},
@@ -91,7 +92,7 @@ func TestParseTaprootDescriptor(t *testing.T) {
 							},
 						},
 						First: &descriptor.Older{
-							Timeout: 604672,
+							Locktime: common.Locktime{Type: common.LocktimeTypeSecond, Value: 604672},
 						},
 					},
 				},
@@ -156,7 +157,7 @@ func TestParseTaprootDescriptor(t *testing.T) {
 							},
 						},
 						First: &descriptor.Older{
-							Timeout: 604672,
+							Locktime: common.Locktime{Type: common.LocktimeTypeSecond, Value: 604672},
 						},
 					},
 					&descriptor.And{
@@ -232,7 +233,7 @@ func TestParseTaprootDescriptor(t *testing.T) {
 					},
 					&descriptor.And{
 						First: &descriptor.Older{
-							Timeout: 512,
+							Locktime: common.Locktime{Type: common.LocktimeTypeSecond, Value: 512},
 						},
 						Second: &descriptor.And{
 							First: &descriptor.PK{
@@ -278,7 +279,7 @@ func TestParseTaprootDescriptor(t *testing.T) {
 					},
 					&descriptor.And{
 						First: &descriptor.Older{
-							Timeout: 1024,
+							Locktime: common.Locktime{Type: common.LocktimeTypeSecond, Value: 1024},
 						},
 						Second: &descriptor.And{
 							First: &descriptor.PK{
@@ -299,7 +300,7 @@ func TestParseTaprootDescriptor(t *testing.T) {
 					},
 					&descriptor.And{
 						First: &descriptor.Older{
-							Timeout: 512,
+							Locktime: common.Locktime{Type: common.LocktimeTypeSecond, Value: 512},
 						},
 						Second: &descriptor.PK{
 							Key: descriptor.XOnlyKey{
@@ -311,7 +312,7 @@ func TestParseTaprootDescriptor(t *testing.T) {
 					},
 					&descriptor.And{
 						First: &descriptor.Older{
-							Timeout: 512,
+							Locktime: common.Locktime{Type: common.LocktimeTypeSecond, Value: 512},
 						},
 						Second: &descriptor.And{
 							First: &descriptor.PK{
@@ -393,7 +394,7 @@ func TestCompileDescriptor(t *testing.T) {
 							},
 						},
 						Second: &descriptor.Older{
-							Timeout: 1024,
+							Locktime: common.Locktime{Type: common.LocktimeTypeSecond, Value: 1024},
 						},
 					},
 				},
@@ -464,14 +465,14 @@ func TestParseOlder(t *testing.T) {
 			policy:         "older(512)",
 			expectedScript: "03010040b275",
 			expected: descriptor.Older{
-				Timeout: uint(512),
+				Locktime: common.Locktime{Type: common.LocktimeTypeSecond, Value: 512},
 			},
 		},
 		{
 			policy:         "older(1024)",
 			expectedScript: "03020040b275",
 			expected: descriptor.Older{
-				Timeout: uint(1024),
+				Locktime: common.Locktime{Type: common.LocktimeTypeSecond, Value: 1024},
 			},
 		},
 	}
@@ -506,7 +507,7 @@ func TestParseAnd(t *testing.T) {
 					},
 				},
 				Second: &descriptor.Older{
-					Timeout: 512,
+					Locktime: common.Locktime{Type: common.LocktimeTypeSecond, Value: 512},
 				},
 			},
 		},
@@ -522,7 +523,7 @@ func TestParseAnd(t *testing.T) {
 					},
 				},
 				First: &descriptor.Older{
-					Timeout: 512,
+					Locktime: common.Locktime{Type: common.LocktimeTypeSecond, Value: 512},
 				},
 			},
 		},
--- a/common/tree/builder.go
+++ b/common/tree/builder.go
@@ -4,6 +4,7 @@ import (
 	"encoding/hex"
 	"fmt"

+	"github.com/ark-network/ark/common"
 	"github.com/btcsuite/btcd/btcec/v2/schnorr"
 	"github.com/btcsuite/btcd/chaincfg/chainhash"
 	"github.com/btcsuite/btcd/txscript"
@@ -14,7 +15,7 @@ import (

 func BuildVtxoTree(
 	asset string, serverPubkey *secp256k1.PublicKey, receivers []VtxoLeaf,
-	feeSatsPerNode uint64, roundLifetime int64,
+	feeSatsPerNode uint64, roundLifetime common.Locktime,
 ) (
 	factoryFn TreeFactory,
 	sharedOutputScript []byte, sharedOutputAmount uint64, err error,
@@ -53,7 +54,7 @@ type node struct {
 	right         *node
 	asset         string
 	feeSats       uint64
-	roundLifetime int64
+	roundLifetime common.Locktime

 	_inputTaprootKey  *secp256k1.PublicKey
 	_inputTaprootTree *taproot.IndexedElementsTapScriptTree
@@ -164,7 +165,7 @@ func (n *node) getWitnessData() (

 	sweepClosure := &CSVSigClosure{
 		MultisigClosure: MultisigClosure{PubKeys: []*secp256k1.PublicKey{n.sweepKey}},
-		Seconds:         uint(n.roundLifetime),
+		Locktime:        n.roundLifetime,
 	}

 	sweepLeaf, err := sweepClosure.Script()
@@ -380,7 +381,7 @@ func (n *node) buildVtxoTree() TreeFactory {

 func buildTreeNodes(
 	asset string, serverPubkey *secp256k1.PublicKey, receivers []VtxoLeaf,
-	feeSatsPerNode uint64, roundLifetime int64,
+	feeSatsPerNode uint64, roundLifetime common.Locktime,
 ) (root *node, err error) {
 	if len(receivers) == 0 {
 		return nil, fmt.Errorf("no receivers provided")
--- a/common/tree/script.go
+++ b/common/tree/script.go
@@ -53,16 +53,25 @@ type MultisigClosure struct {
 }

 // CSVSigClosure is a closure that contains a list of public keys and a
-// CHECKSEQUENCEVERIFY + DROP. The witness size is 64 bytes per key, admitting
+// CHECKSEQUENCEVERIFY. The witness size is 64 bytes per key, admitting
 // the sighash type is SIGHASH_DEFAULT.
 type CSVSigClosure struct {
 	MultisigClosure
-	Seconds uint
+	Locktime common.Locktime
+}
+
+// CLTVMultisigClosure is a closure that contains a list of public keys and a
+// CHECKLOCKTIMEVERIFY. The witness size is 64 bytes per key, admitting
+// the sighash type is SIGHASH_DEFAULT.
+type CLTVMultisigClosure struct {
+	MultisigClosure
+	Locktime common.Locktime
 }

 func DecodeClosure(script []byte) (Closure, error) {
 	types := []Closure{
 		&CSVSigClosure{},
+		&CLTVMultisigClosure{},
 		&MultisigClosure{},
 		&UnrollClosure{},
 	}
@@ -324,8 +333,13 @@ func (f *CSVSigClosure) WitnessSize() int {
 }

 func (d *CSVSigClosure) Script() ([]byte, error) {
+	sequence, err := common.BIP68Sequence(d.Locktime)
+	if err != nil {
+		return nil, err
+	}
+
 	csvScript, err := txscript.NewScriptBuilder().
-		AddInt64(int64(d.Seconds)).
+		AddInt64(int64(sequence)).
 		AddOps([]byte{
 			txscript.OP_CHECKSEQUENCEVERIFY,
 			txscript.OP_DROP,
@@ -360,7 +374,7 @@ func (d *CSVSigClosure) Decode(script []byte) (bool, error) {
 		sequence = sequence[1:]
 	}

-	seconds, err := common.BIP68DecodeSequence(sequence)
+	locktime, err := common.BIP68DecodeSequence(sequence)
 	if err != nil {
 		return false, err
 	}
@@ -375,7 +389,7 @@ func (d *CSVSigClosure) Decode(script []byte) (bool, error) {
 		return false, nil
 	}

-	d.Seconds = seconds
+	d.Locktime = *locktime
 	d.MultisigClosure = *multisigClosure

 	return valid, nil
@@ -666,3 +680,87 @@ func (c *UnrollClosure) Witness(controlBlock []byte, _ map[string][]byte) (wire.
 	// UnrollClosure only needs script and control block
 	return wire.TxWitness{script, controlBlock}, nil
 }
+
+func (f *CLTVMultisigClosure) Witness(controlBlock []byte, signatures map[string][]byte) (wire.TxWitness, error) {
+	multisigWitness, err := f.MultisigClosure.Witness(controlBlock, signatures)
+	if err != nil {
+		return nil, err
+	}
+
+	script, err := f.Script()
+	if err != nil {
+		return nil, fmt.Errorf("failed to generate script: %w", err)
+	}
+
+	// replace script with cltv script
+	multisigWitness[len(multisigWitness)-2] = script
+
+	return multisigWitness, nil
+}
+
+func (f *CLTVMultisigClosure) WitnessSize() int {
+	return f.MultisigClosure.WitnessSize()
+}
+
+func (d *CLTVMultisigClosure) Script() ([]byte, error) {
+	locktime, err := common.BIP68Sequence(d.Locktime)
+	if err != nil {
+		return nil, err
+	}
+
+	cltvScript, err := txscript.NewScriptBuilder().
+		AddInt64(int64(locktime)).
+		AddOps([]byte{
+			txscript.OP_CHECKLOCKTIMEVERIFY,
+			txscript.OP_DROP,
+		}).
+		Script()
+	if err != nil {
+		return nil, err
+	}
+
+	multisigScript, err := d.MultisigClosure.Script()
+	if err != nil {
+		return nil, err
+	}
+
+	return append(cltvScript, multisigScript...), nil
+}
+
+func (d *CLTVMultisigClosure) Decode(script []byte) (bool, error) {
+	if len(script) == 0 {
+		return false, fmt.Errorf("empty script")
+	}
+
+	cltvIndex := bytes.Index(
+		script, []byte{txscript.OP_CHECKLOCKTIMEVERIFY, txscript.OP_DROP},
+	)
+	if cltvIndex == -1 || cltvIndex == 0 {
+		return false, nil
+	}
+
+	locktime := script[:cltvIndex]
+	if len(locktime) > 1 {
+		locktime = locktime[1:]
+	}
+
+	locktimeValue, err := common.BIP68DecodeSequence(locktime)
+	if err != nil {
+		return false, err
+	}
+
+	multisigClosure := &MultisigClosure{}
+	valid, err := multisigClosure.Decode(script[cltvIndex+2:])
+	if err != nil {
+		return false, err
+	}
+
+	if !valid {
+		return false, nil
+	}
+
+	d.Locktime = *locktimeValue
+	d.MultisigClosure = *multisigClosure
+
+	return valid, nil
+}
--- a/common/tree/script_test.go
+++ b/common/tree/script_test.go
@@ -1,9 +1,11 @@
 package tree_test

 import (
+	"bytes"
 	"encoding/hex"
 	"testing"

+	"github.com/ark-network/ark/common"
 	"github.com/ark-network/ark/common/tree"
 	"github.com/btcsuite/btcd/btcec/v2/schnorr"
 	"github.com/btcsuite/btcd/txscript"
@@ -19,7 +21,7 @@ func TestRoundTripCSV(t *testing.T) {
 		MultisigClosure: tree.MultisigClosure{
 			PubKeys: []*secp256k1.PublicKey{seckey.PubKey()},
 		},
-		Seconds: 1024,
+		Locktime: common.Locktime{Type: common.LocktimeTypeSecond, Value: 1024},
 	}

 	leaf, err := csvSig.Script()
@@ -31,7 +33,7 @@ func TestRoundTripCSV(t *testing.T) {
 	require.NoError(t, err)
 	require.True(t, valid)

-	require.Equal(t, csvSig.Seconds, cl.Seconds)
+	require.Equal(t, csvSig.Locktime.Value, cl.Locktime.Value)
 }

 func TestMultisigClosure(t *testing.T) {
@@ -194,7 +196,7 @@ func TestCSVSigClosure(t *testing.T) {
 			MultisigClosure: tree.MultisigClosure{
 				PubKeys: []*secp256k1.PublicKey{pubkey1},
 			},
-			Seconds: 1024,
+			Locktime: common.Locktime{Type: common.LocktimeTypeSecond, Value: 1024},
 		}

 		script, err := csvSig.Script()
@@ -204,7 +206,7 @@ func TestCSVSigClosure(t *testing.T) {
 		valid, err := decodedCSV.Decode(script)
 		require.NoError(t, err)
 		require.True(t, valid)
-		require.Equal(t, uint32(1024), uint32(decodedCSV.Seconds))
+		require.Equal(t, uint32(1024), uint32(decodedCSV.Locktime.Value))
 		require.Equal(t, 1, len(decodedCSV.PubKeys))
 		require.Equal(t,
 			schnorr.SerializePubKey(pubkey1),
@@ -217,7 +219,7 @@ func TestCSVSigClosure(t *testing.T) {
 			MultisigClosure: tree.MultisigClosure{
 				PubKeys: []*secp256k1.PublicKey{pubkey1, pubkey2},
 			},
-			Seconds: 2016, // ~2 weeks
+			Locktime: common.Locktime{Type: common.LocktimeTypeSecond, Value: 512 * 4}, // ~2 weeks
 		}

 		script, err := csvSig.Script()
@@ -227,7 +229,7 @@ func TestCSVSigClosure(t *testing.T) {
 		valid, err := decodedCSV.Decode(script)
 		require.NoError(t, err)
 		require.True(t, valid)
-		require.Equal(t, uint32(2016), uint32(decodedCSV.Seconds))
+		require.Equal(t, uint32(512*4), uint32(decodedCSV.Locktime.Value))
 		require.Equal(t, 2, len(decodedCSV.PubKeys))
 		require.Equal(t,
 			schnorr.SerializePubKey(pubkey1),
@@ -265,7 +267,7 @@ func TestCSVSigClosure(t *testing.T) {
 			MultisigClosure: tree.MultisigClosure{
 				PubKeys: []*secp256k1.PublicKey{pubkey1, pubkey2},
 			},
-			Seconds: 1024,
+			Locktime: common.Locktime{Type: common.LocktimeTypeSecond, Value: 1024},
 		}
 		// Should be same as multisig witness size (64 bytes per signature)
 		require.Equal(t, 128, csvSig.WitnessSize())
@@ -276,7 +278,7 @@ func TestCSVSigClosure(t *testing.T) {
 			MultisigClosure: tree.MultisigClosure{
 				PubKeys: []*secp256k1.PublicKey{pubkey1},
 			},
-			Seconds: 65535, // Maximum allowed value
+			Locktime: common.Locktime{Type: common.LocktimeTypeSecond, Value: common.SECONDS_MAX}, // Maximum allowed value
 		}

 		script, err := csvSig.Script()
@@ -286,7 +288,7 @@ func TestCSVSigClosure(t *testing.T) {
 		valid, err := decodedCSV.Decode(script)
 		require.NoError(t, err)
 		require.True(t, valid)
-		require.Equal(t, uint32(65535), uint32(decodedCSV.Seconds))
+		require.Equal(t, uint32(common.SECONDS_MAX), decodedCSV.Locktime.Value)
 	})
 }

@@ -416,7 +418,7 @@ func TestCSVSigClosureWitness(t *testing.T) {
 		MultisigClosure: tree.MultisigClosure{
 			PubKeys: []*secp256k1.PublicKey{pub1},
 		},
-		Seconds: 144,
+		Locktime: common.Locktime{Type: common.LocktimeTypeBlock, Value: 144},
 	}

 	witness, err := closure.Witness(controlBlock, signatures)
@@ -469,3 +471,156 @@ func TestDecodeChecksigAdd(t *testing.T) {
 	require.Equal(t, tree.MultisigTypeChecksigAdd, multisigClosure.Type, "expected MultisigTypeChecksigAdd")
 	require.Equal(t, 3, len(multisigClosure.PubKeys), "expected 3 public keys")
 }
+
+func TestCLTVMultisigClosure(t *testing.T) {
+	// Generate test keys
+	privkey1, err := secp256k1.GeneratePrivateKey()
+	require.NoError(t, err)
+	pubkey1 := privkey1.PubKey()
+
+	privkey2, err := secp256k1.GeneratePrivateKey()
+	require.NoError(t, err)
+	pubkey2 := privkey2.PubKey()
+
+	locktime := common.Locktime{
+		Type:  common.LocktimeTypeBlock,
+		Value: 100,
+	}
+
+	t.Run("valid single key with CLTV", func(t *testing.T) {
+		closure := &tree.CLTVMultisigClosure{
+			MultisigClosure: tree.MultisigClosure{
+				PubKeys: []*secp256k1.PublicKey{pubkey1},
+				Type:    tree.MultisigTypeChecksig,
+			},
+			Locktime: locktime,
+		}
+
+		script, err := closure.Script()
+		require.NoError(t, err)
+
+		decodedClosure := &tree.CLTVMultisigClosure{}
+		valid, err := decodedClosure.Decode(script)
+		require.NoError(t, err)
+		require.True(t, valid)
+		require.Equal(t, closure.Locktime, decodedClosure.Locktime)
+		require.Equal(t, 1, len(decodedClosure.PubKeys))
+		require.True(t, closure.PubKeys[0].IsEqual(decodedClosure.PubKeys[0]))
+	})
+
+	t.Run("valid two keys with CLTV", func(t *testing.T) {
+		closure := &tree.CLTVMultisigClosure{
+			MultisigClosure: tree.MultisigClosure{
+				PubKeys: []*secp256k1.PublicKey{pubkey1, pubkey2},
+				Type:    tree.MultisigTypeChecksig,
+			},
+			Locktime: locktime,
+		}
+
+		script, err := closure.Script()
+		require.NoError(t, err)
+
+		decodedClosure := &tree.CLTVMultisigClosure{}
+		valid, err := decodedClosure.Decode(script)
+		require.NoError(t, err)
+		require.True(t, valid)
+		require.Equal(t, closure.Locktime, decodedClosure.Locktime)
+		require.Equal(t, 2, len(decodedClosure.PubKeys))
+	})
+
+	t.Run("valid two keys with CLTV using checksigadd", func(t *testing.T) {
+		closure := &tree.CLTVMultisigClosure{
+			MultisigClosure: tree.MultisigClosure{
+				PubKeys: []*secp256k1.PublicKey{pubkey1, pubkey2},
+				Type:    tree.MultisigTypeChecksigAdd,
+			},
+			Locktime: locktime,
+		}
+
+		script, err := closure.Script()
+		require.NoError(t, err)
+
+		decodedClosure := &tree.CLTVMultisigClosure{}
+		valid, err := decodedClosure.Decode(script)
+		require.NoError(t, err)
+		require.True(t, valid)
+		require.Equal(t, closure.Locktime, decodedClosure.Locktime)
+		require.Equal(t, closure.Type, decodedClosure.Type)
+		require.Equal(t, 2, len(decodedClosure.PubKeys))
+	})
+
+	t.Run("witness generation", func(t *testing.T) {
+		closure := &tree.CLTVMultisigClosure{
+			MultisigClosure: tree.MultisigClosure{
+				PubKeys: []*secp256k1.PublicKey{pubkey1, pubkey2},
+				Type:    tree.MultisigTypeChecksig,
+			},
+			Locktime: locktime,
+		}
+
+		controlBlock := bytes.Repeat([]byte{0x00}, 32)
+		signatures := map[string][]byte{
+			hex.EncodeToString(schnorr.SerializePubKey(pubkey1)): bytes.Repeat([]byte{0x01}, 64),
+			hex.EncodeToString(schnorr.SerializePubKey(pubkey2)): bytes.Repeat([]byte{0x01}, 64),
+		}
+
+		witness, err := closure.Witness(controlBlock, signatures)
+		require.NoError(t, err)
+		require.Equal(t, 4, len(witness)) // 2 sigs + script + control block
+
+		script, err := closure.Script()
+		require.NoError(t, err)
+		require.Equal(t, script, witness[2])
+		require.Equal(t, controlBlock, witness[3])
+	})
+
+	t.Run("invalid cases", func(t *testing.T) {
+		validClosure := &tree.CLTVMultisigClosure{
+			MultisigClosure: tree.MultisigClosure{
+				PubKeys: []*secp256k1.PublicKey{pubkey1},
+				Type:    tree.MultisigTypeChecksig,
+			},
+			Locktime: locktime,
+		}
+		script, err := validClosure.Script()
+		require.NoError(t, err)
+		emptyScriptErr := "empty script"
+
+		testCases := []struct {
+			name   string
+			script []byte
+			err    *string
+		}{
+			{
+				name:   "empty script",
+				script: []byte{},
+				err:    &emptyScriptErr,
+			},
+			{
+				name:   "invalid CLTV index",
+				script: append([]byte{txscript.OP_CHECKLOCKTIMEVERIFY, txscript.OP_DROP}, script...),
+			},
+			{
+				name:   "missing CLTV",
+				script: script[5:],
+			},
+			{
+				name:   "invalid multisig after CLTV",
+				script: append(script[:len(script)-1], txscript.OP_CHECKSIGVERIFY),
+			},
+		}
+
+		for _, tc := range testCases {
+			t.Run(tc.name, func(t *testing.T) {
+				closure := &tree.CLTVMultisigClosure{}
+				valid, err := closure.Decode(tc.script)
+				require.False(t, valid)
+				if tc.err != nil {
+					require.Contains(t, err.Error(), *tc.err)
+				} else {
+					require.NoError(t, err)
+				}
+			})
+		}
+	})
+}
--- a/common/tree/validation.go
+++ b/common/tree/validation.go
@@ -5,6 +5,7 @@ import (
 	"errors"
 	"fmt"

+	"github.com/ark-network/ark/common"
 	"github.com/btcsuite/btcd/btcec/v2/schnorr"
 	"github.com/btcsuite/btcd/chaincfg/chainhash"
 	"github.com/decred/dcrd/dcrec/secp256k1/v4"
@@ -72,7 +73,7 @@ func UnspendableKey() *secp256k1.PublicKey {
 // - input and output amounts
 func ValidateVtxoTree(
 	tree VtxoTree, roundTx string, serverPubkey *secp256k1.PublicKey,
-	roundLifetime int64,
+	roundLifetime common.Locktime,
 ) error {
 	roundTransaction, err := psetv2.NewPsetFromBase64(roundTx)
 	if err != nil {
@@ -148,7 +149,7 @@ func ValidateVtxoTree(
 func validateNodeTransaction(
 	node Node, tree VtxoTree,
 	expectedInternalKey, expectedServerPubkey *secp256k1.PublicKey,
-	expectedSequence int64,
+	expectedLifetime common.Locktime,
 ) error {
 	if node.Tx == "" {
 		return ErrNodeTxEmpty
@@ -242,7 +243,8 @@ func validateNodeTransaction(
 					schnorr.SerializePubKey(c.MultisigClosure.PubKeys[0]),
 					schnorr.SerializePubKey(expectedServerPubkey),
 				)
-				isSweepDelay := int64(c.Seconds) == expectedSequence
+
+				isSweepDelay := c.Locktime == expectedLifetime

 				if isServer && !isSweepDelay {
 					return ErrInvalidSweepSequence
--- a/common/tree/vtxo.go
+++ b/common/tree/vtxo.go
@@ -4,7 +4,6 @@ import (
 	"bytes"
 	"encoding/hex"
 	"fmt"
-	"math"

 	"github.com/ark-network/ark/common"
 	"github.com/btcsuite/btcd/btcec/v2/schnorr"
@@ -17,7 +16,7 @@ var (
 	ErrNoExitLeaf = fmt.Errorf("no exit leaf")
 )

-type VtxoScript common.VtxoScript[elementsTapTree, *MultisigClosure, *CSVSigClosure]
+type VtxoScript common.VtxoScript[elementsTapTree, Closure]

 func ParseVtxoScript(scripts []string) (VtxoScript, error) {
 	v := &TapscriptsVtxoScript{}
@@ -26,12 +25,12 @@ func ParseVtxoScript(scripts []string) (VtxoScript, error) {
 	return v, err
 }

-func NewDefaultVtxoScript(owner, server *secp256k1.PublicKey, exitDelay uint) *TapscriptsVtxoScript {
+func NewDefaultVtxoScript(owner, server *secp256k1.PublicKey, exitDelay common.Locktime) *TapscriptsVtxoScript {
 	return &TapscriptsVtxoScript{
 		[]Closure{
 			&CSVSigClosure{
 				MultisigClosure: MultisigClosure{PubKeys: []*secp256k1.PublicKey{owner}},
-				Seconds:         exitDelay,
+				Locktime:        exitDelay,
 			},
 			&MultisigClosure{PubKeys: []*secp256k1.PublicKey{owner, server}},
 		},
@@ -73,12 +72,17 @@ func (v *TapscriptsVtxoScript) Decode(scripts []string) error {
 	return nil
 }

-func (v *TapscriptsVtxoScript) Validate(server *secp256k1.PublicKey, minExitDelay uint) error {
+func (v *TapscriptsVtxoScript) Validate(server *secp256k1.PublicKey, minLocktime common.Locktime) error {
 	serverXonly := schnorr.SerializePubKey(server)
 	for _, forfeit := range v.ForfeitClosures() {
+		multisigClosure, ok := forfeit.(*MultisigClosure)
+		if !ok {
+			return fmt.Errorf("invalid forfeit closure, expected MultisigClosure")
+		}
+
 		// must contain server pubkey
 		found := false
-		for _, pubkey := range forfeit.PubKeys {
+		for _, pubkey := range multisigClosure.PubKeys {
 			if bytes.Equal(schnorr.SerializePubKey(pubkey), serverXonly) {
 				found = true
 				break
@@ -97,46 +101,48 @@ func (v *TapscriptsVtxoScript) Validate(server *secp256k1.PublicKey, minExitDela
 		return err
 	}

-	if smallestExit < minExitDelay {
+	if smallestExit.LessThan(minLocktime) {
 		return fmt.Errorf("exit delay is too short")
 	}

 	return nil
 }

-func (v *TapscriptsVtxoScript) SmallestExitDelay() (uint, error) {
-	smallest := uint(math.MaxUint32)
+func (v *TapscriptsVtxoScript) SmallestExitDelay() (*common.Locktime, error) {
+	var smallest *common.Locktime

 	for _, closure := range v.Closures {
 		if csvClosure, ok := closure.(*CSVSigClosure); ok {
-			if csvClosure.Seconds < smallest {
-				smallest = csvClosure.Seconds
+			if smallest == nil || csvClosure.Locktime.LessThan(*smallest) {
+				smallest = &csvClosure.Locktime
 			}
 		}
 	}

-	if smallest == math.MaxUint32 {
-		return 0, ErrNoExitLeaf
+	if smallest == nil {
+		return nil, ErrNoExitLeaf
 	}

 	return smallest, nil
 }

-func (v *TapscriptsVtxoScript) ForfeitClosures() []*MultisigClosure {
-	forfeits := make([]*MultisigClosure, 0)
+func (v *TapscriptsVtxoScript) ForfeitClosures() []Closure {
+	forfeits := make([]Closure, 0)
 	for _, closure := range v.Closures {
-		if multisigClosure, ok := closure.(*MultisigClosure); ok {
-			forfeits = append(forfeits, multisigClosure)
+		switch closure.(type) {
+		case *MultisigClosure, *CLTVMultisigClosure:
+			forfeits = append(forfeits, closure)
 		}
 	}
 	return forfeits
 }

-func (v *TapscriptsVtxoScript) ExitClosures() []*CSVSigClosure {
-	exits := make([]*CSVSigClosure, 0)
+func (v *TapscriptsVtxoScript) ExitClosures() []Closure {
+	exits := make([]Closure, 0)
 	for _, closure := range v.Closures {
-		if csvClosure, ok := closure.(*CSVSigClosure); ok {
-			exits = append(exits, csvClosure)
+		switch closure.(type) {
+		case *CSVSigClosure:
+			exits = append(exits, closure)
 		}
 	}
 	return exits
--- a/common/vtxo.go
+++ b/common/vtxo.go
@@ -31,15 +31,17 @@ It may also contain others closures implementing specific use cases.

 VtxoScript abstracts the taproot complexity behind vtxo contracts.
 it is compiled, transferred and parsed using descriptor string.
+
+// TODO gather common and tree package to prevent circular dependency and move C generic
 */
-type VtxoScript[T TaprootTree, F interface{}, E interface{}] interface {
-	Validate(server *secp256k1.PublicKey, minExitDelay uint) error
+type VtxoScript[T TaprootTree, C interface{}] interface {
+	Validate(server *secp256k1.PublicKey, minLocktime Locktime) error
 	TapTree() (taprootKey *secp256k1.PublicKey, taprootScriptTree T, err error)
 	Encode() ([]string, error)
 	Decode(scripts []string) error
-	SmallestExitDelay() (uint, error)
-	ForfeitClosures() []F
-	ExitClosures() []E
+	SmallestExitDelay() (*Locktime, error)
+	ForfeitClosures() []C
+	ExitClosures() []C
 }

 // BiggestLeafMerkleProof returns the leaf with the biggest witness size (for fee estimation)
--- a/pkg/client-sdk/client.go
+++ b/pkg/client-sdk/client.go
@@ -146,15 +146,25 @@ func (a *arkClient) initWithWallet(
 		return fmt.Errorf("failed to parse server pubkey: %s", err)
 	}

+	lifetimeType := common.LocktimeTypeBlock
+	if info.RoundLifetime >= 512 {
+		lifetimeType = common.LocktimeTypeSecond
+	}
+
+	unilateralExitDelayType := common.LocktimeTypeBlock
+	if info.UnilateralExitDelay >= 512 {
+		unilateralExitDelayType = common.LocktimeTypeSecond
+	}
+
 	storeData := types.Config{
 		ServerUrl:                  args.ServerUrl,
 		ServerPubKey:               serverPubkey,
 		WalletType:                 args.Wallet.GetType(),
 		ClientType:                 args.ClientType,
 		Network:                    network,
-		RoundLifetime:              info.RoundLifetime,
+		RoundLifetime:              common.Locktime{Type: lifetimeType, Value: uint32(info.RoundLifetime)},
 		RoundInterval:              info.RoundInterval,
-		UnilateralExitDelay:        info.UnilateralExitDelay,
+		UnilateralExitDelay:        common.Locktime{Type: unilateralExitDelayType, Value: uint32(info.UnilateralExitDelay)},
 		Dust:                       info.Dust,
 		BoardingDescriptorTemplate: info.BoardingDescriptorTemplate,
 		ForfeitAddress:             info.ForfeitAddress,
@@ -213,15 +223,25 @@ func (a *arkClient) init(
 		return fmt.Errorf("failed to parse server pubkey: %s", err)
 	}

+	lifetimeType := common.LocktimeTypeBlock
+	if info.RoundLifetime >= 512 {
+		lifetimeType = common.LocktimeTypeSecond
+	}
+
+	unilateralExitDelayType := common.LocktimeTypeBlock
+	if info.UnilateralExitDelay >= 512 {
+		unilateralExitDelayType = common.LocktimeTypeSecond
+	}
+
 	cfgData := types.Config{
 		ServerUrl:                  args.ServerUrl,
 		ServerPubKey:               serverPubkey,
 		WalletType:                 args.WalletType,
 		ClientType:                 args.ClientType,
 		Network:                    network,
-		RoundLifetime:              info.RoundLifetime,
+		RoundLifetime:              common.Locktime{Type: lifetimeType, Value: uint32(info.RoundLifetime)},
 		RoundInterval:              info.RoundInterval,
-		UnilateralExitDelay:        info.UnilateralExitDelay,
+		UnilateralExitDelay:        common.Locktime{Type: unilateralExitDelayType, Value: uint32(info.UnilateralExitDelay)},
 		Dust:                       info.Dust,
 		BoardingDescriptorTemplate: info.BoardingDescriptorTemplate,
 		ExplorerURL:                args.ExplorerURL,
@@ -347,8 +367,8 @@ func getWalletStore(storeType, datadir string) (walletstore.WalletStore, error)
 	}
 }

-func getCreatedAtFromExpiry(roundLifetime int64, expiry time.Time) time.Time {
-	return expiry.Add(-time.Duration(roundLifetime) * time.Second)
+func getCreatedAtFromExpiry(roundLifetime common.Locktime, expiry time.Time) time.Time {
+	return expiry.Add(-time.Duration(roundLifetime.Seconds()) * time.Second)
 }

 func filterByOutpoints(vtxos []client.Vtxo, outpoints []client.Outpoint) []client.Vtxo {
--- a/pkg/client-sdk/covenant_client.go
+++ b/pkg/client-sdk/covenant_client.go
@@ -708,7 +708,7 @@ func (a *covenantArkClient) getClaimableBoardingUtxos(ctx context.Context, opts
 				}
 			}

-			u := utxo.ToUtxo(boardingTimeout, addr.Tapscripts)
+			u := utxo.ToUtxo(*boardingTimeout, addr.Tapscripts)
 			if u.SpendableAt.Before(now) {
 				continue
 			}
@@ -1535,7 +1535,7 @@ func (a *covenantArkClient) coinSelectOnchain(
 		}

 		for _, utxo := range utxos {
-			u := utxo.ToUtxo(boardingTimeout, addr.Tapscripts)
+			u := utxo.ToUtxo(*boardingTimeout, addr.Tapscripts)
 			if u.SpendableAt.Before(now) {
 				fetchedUtxos = append(fetchedUtxos, u)
 			}
@@ -1571,7 +1571,7 @@ func (a *covenantArkClient) coinSelectOnchain(
 		}

 		for _, utxo := range utxos {
-			u := utxo.ToUtxo(uint(a.UnilateralExitDelay), addr.Tapscripts)
+			u := utxo.ToUtxo(a.UnilateralExitDelay, addr.Tapscripts)
 			if u.SpendableAt.Before(now) {
 				fetchedUtxos = append(fetchedUtxos, u)
 			}
@@ -1719,7 +1719,7 @@ func (a *covenantArkClient) getBoardingTxs(ctx context.Context) (transactions []
 }

 func vtxosToTxsCovenant(
-	roundLifetime int64, spendable, spent []client.Vtxo, boardingTxs []types.Transaction,
+	roundLifetime common.Locktime, spendable, spent []client.Vtxo, boardingTxs []types.Transaction,
 ) ([]types.Transaction, error) {
 	transactions := make([]types.Transaction, 0)
 	unconfirmedBoardingTxs := make([]types.Transaction, 0)
--- a/pkg/client-sdk/covenantless_client.go
+++ b/pkg/client-sdk/covenantless_client.go
@@ -1703,7 +1703,7 @@ func (a *covenantlessArkClient) handleRoundSigningStarted(
 ) (signerSession bitcointree.SignerSession, err error) {
 	sweepClosure := tree.CSVSigClosure{
 		MultisigClosure: tree.MultisigClosure{PubKeys: []*secp256k1.PublicKey{a.ServerPubKey}},
-		Seconds:         uint(a.RoundLifetime),
+		Locktime:        a.RoundLifetime,
 	}

 	script, err := sweepClosure.Script()
@@ -2163,7 +2163,7 @@ func (a *covenantlessArkClient) coinSelectOnchain(
 		}

 		for _, utxo := range utxos {
-			u := utxo.ToUtxo(boardingTimeout, addr.Tapscripts)
+			u := utxo.ToUtxo(*boardingTimeout, addr.Tapscripts)
 			if u.SpendableAt.Before(now) {
 				fetchedUtxos = append(fetchedUtxos, u)
 			}
@@ -2199,7 +2199,7 @@ func (a *covenantlessArkClient) coinSelectOnchain(
 		}

 		for _, utxo := range utxos {
-			u := utxo.ToUtxo(uint(a.UnilateralExitDelay), addr.Tapscripts)
+			u := utxo.ToUtxo(a.UnilateralExitDelay, addr.Tapscripts)
 			if u.SpendableAt.Before(now) {
 				fetchedUtxos = append(fetchedUtxos, u)
 			}
@@ -2387,7 +2387,7 @@ func (a *covenantlessArkClient) getClaimableBoardingUtxos(ctx context.Context, o
 				}
 			}

-			u := utxo.ToUtxo(boardingTimeout, addr.Tapscripts)
+			u := utxo.ToUtxo(*boardingTimeout, addr.Tapscripts)
 			if u.SpendableAt.Before(now) {
 				continue
 			}
@@ -2682,5 +2682,5 @@ func buildRedeemTx(
 		})
 	}

-	return bitcointree.BuildRedeemTx(ins, outs, fees)
+	return bitcointree.BuildRedeemTx(ins, outs)
 }
--- a/pkg/client-sdk/explorer/explorer.go
+++ b/pkg/client-sdk/explorer/explorer.go
@@ -53,7 +53,7 @@ type SpentStatus struct {
 	SpentBy string `json:"txid,omitempty"`
 }

-func (e ExplorerUtxo) ToUtxo(delay uint, tapscripts []string) types.Utxo {
+func (e ExplorerUtxo) ToUtxo(delay common.Locktime, tapscripts []string) types.Utxo {
 	return newUtxo(e, delay, tapscripts)
 }

@@ -65,7 +65,7 @@ type Explorer interface {
 	GetUtxos(addr string) ([]ExplorerUtxo, error)
 	GetBalance(addr string) (uint64, error)
 	GetRedeemedVtxosBalance(
-		addr string, unilateralExitDelay int64,
+		addr string, unilateralExitDelay common.Locktime,
 	) (uint64, map[int64]uint64, error)
 	GetTxBlockTime(
 		txid string,
@@ -247,7 +247,7 @@ func (e *explorerSvc) GetBalance(addr string) (uint64, error) {
 }

 func (e *explorerSvc) GetRedeemedVtxosBalance(
-	addr string, unilateralExitDelay int64,
+	addr string, unilateralExitDelay common.Locktime,
 ) (spendableBalance uint64, lockedBalance map[int64]uint64, err error) {
 	utxos, err := e.GetUtxos(addr)
 	if err != nil {
@@ -262,7 +262,7 @@ func (e *explorerSvc) GetRedeemedVtxosBalance(
 			blocktime = time.Unix(utxo.Status.Blocktime, 0)
 		}

-		delay := time.Duration(unilateralExitDelay) * time.Second
+		delay := time.Duration(unilateralExitDelay.Seconds()) * time.Second
 		availableAt := blocktime.Add(delay)
 		if availableAt.After(now) {
 			if _, ok := lockedBalance[availableAt.Unix()]; !ok {
@@ -415,7 +415,7 @@ func parseBitcoinTx(txStr string) (string, string, error) {
 	return txhex, txid, nil
 }

-func newUtxo(explorerUtxo ExplorerUtxo, delay uint, tapscripts []string) types.Utxo {
+func newUtxo(explorerUtxo ExplorerUtxo, delay common.Locktime, tapscripts []string) types.Utxo {
 	utxoTime := explorerUtxo.Status.Blocktime
 	createdAt := time.Unix(utxoTime, 0)
 	if utxoTime == 0 {
@@ -429,7 +429,7 @@ func newUtxo(explorerUtxo ExplorerUtxo, delay uint, tapscripts []string) types.U
 		Amount:      explorerUtxo.Amount,
 		Asset:       explorerUtxo.Asset,
 		Delay:       delay,
-		SpendableAt: time.Unix(utxoTime, 0).Add(time.Duration(delay) * time.Second),
+		SpendableAt: time.Unix(utxoTime, 0).Add(time.Duration(delay.Seconds()) * time.Second),
 		CreatedAt:   createdAt,
 		Tapscripts:  tapscripts,
 	}
--- a/pkg/client-sdk/redemption/covenant_redeem.go
+++ b/pkg/client-sdk/redemption/covenant_redeem.go
@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"time"

+	"github.com/ark-network/ark/common"
 	"github.com/ark-network/ark/common/tree"
 	"github.com/ark-network/ark/pkg/client-sdk/client"
 	"github.com/ark-network/ark/pkg/client-sdk/explorer"
@@ -26,12 +27,12 @@ func NewCovenantRedeemBranch(
 	explorer explorer.Explorer,
 	vtxoTree tree.VtxoTree, vtxo client.Vtxo,
 ) (*CovenantRedeemBranch, error) {
-	sweepClosure, seconds, err := findCovenantSweepClosure(vtxoTree)
+	sweepClosure, locktime, err := findCovenantSweepClosure(vtxoTree)
 	if err != nil {
 		return nil, err
 	}

-	lifetime, err := time.ParseDuration(fmt.Sprintf("%ds", seconds))
+	lifetime, err := time.ParseDuration(fmt.Sprintf("%ds", locktime.Seconds()))
 	if err != nil {
 		return nil, err
 	}
@@ -183,19 +184,19 @@ func (r *CovenantRedeemBranch) offchainPath() ([]*psetv2.Pset, error) {

 func findCovenantSweepClosure(
 	vtxoTree tree.VtxoTree,
-) (*taproot.TapElementsLeaf, uint, error) {
+) (*taproot.TapElementsLeaf, *common.Locktime, error) {
 	root, err := vtxoTree.Root()
 	if err != nil {
-		return nil, 0, err
+		return nil, nil, err
 	}

 	// find the sweep closure
 	tx, err := psetv2.NewPsetFromBase64(root.Tx)
 	if err != nil {
-		return nil, 0, err
+		return nil, nil, err
 	}

-	var seconds uint
+	var locktime *common.Locktime
 	var sweepClosure *taproot.TapElementsLeaf
 	for _, tapLeaf := range tx.Inputs[0].TapLeafScript {
 		closure := &tree.CSVSigClosure{}
@@ -204,15 +205,15 @@ func findCovenantSweepClosure(
 			continue
 		}

-		if valid && closure.Seconds > seconds {
-			seconds = closure.Seconds
+		if valid && (locktime == nil || closure.Locktime.LessThan(*locktime)) {
+			locktime = &closure.Locktime
 			sweepClosure = &tapLeaf.TapElementsLeaf
 		}
 	}

 	if sweepClosure == nil {
-		return nil, 0, fmt.Errorf("sweep closure not found")
+		return nil, nil, fmt.Errorf("sweep closure not found")
 	}

-	return sweepClosure, seconds, nil
+	return sweepClosure, locktime, nil
 }
--- a/pkg/client-sdk/redemption/covenantless_redeem.go
+++ b/pkg/client-sdk/redemption/covenantless_redeem.go
@@ -7,6 +7,7 @@ import (
 	"strings"
 	"time"

+	"github.com/ark-network/ark/common"
 	"github.com/ark-network/ark/common/tree"
 	"github.com/ark-network/ark/pkg/client-sdk/client"
 	"github.com/ark-network/ark/pkg/client-sdk/explorer"
@@ -25,12 +26,12 @@ func NewCovenantlessRedeemBranch(
 	explorer explorer.Explorer,
 	vtxoTree tree.VtxoTree, vtxo client.Vtxo,
 ) (*CovenantlessRedeemBranch, error) {
-	_, seconds, err := findCovenantlessSweepClosure(vtxoTree)
+	_, locktime, err := findCovenantlessSweepClosure(vtxoTree)
 	if err != nil {
 		return nil, err
 	}

-	lifetime, err := time.ParseDuration(fmt.Sprintf("%ds", seconds))
+	lifetime, err := time.ParseDuration(fmt.Sprintf("%ds", locktime.Seconds()))
 	if err != nil {
 		return nil, err
 	}
@@ -156,19 +157,19 @@ func (r *CovenantlessRedeemBranch) OffchainPath() ([]*psbt.Packet, error) {

 func findCovenantlessSweepClosure(
 	vtxoTree tree.VtxoTree,
-) (*txscript.TapLeaf, uint, error) {
+) (*txscript.TapLeaf, *common.Locktime, error) {
 	root, err := vtxoTree.Root()
 	if err != nil {
-		return nil, 0, err
+		return nil, nil, err
 	}

 	// find the sweep closure
 	tx, err := psbt.NewFromRawBytes(strings.NewReader(root.Tx), true)
 	if err != nil {
-		return nil, 0, err
+		return nil, nil, err
 	}

-	var seconds uint
+	var locktime *common.Locktime
 	var sweepClosure *txscript.TapLeaf
 	for _, tapLeaf := range tx.Inputs[0].TaprootLeafScript {
 		closure := &tree.CSVSigClosure{}
@@ -177,16 +178,16 @@ func findCovenantlessSweepClosure(
 			continue
 		}

-		if valid && closure.Seconds > seconds {
-			seconds = closure.Seconds
+		if valid && (locktime == nil || closure.Locktime.LessThan(*locktime)) {
+			locktime = &closure.Locktime
 			leaf := txscript.NewBaseTapLeaf(tapLeaf.Script)
 			sweepClosure = &leaf
 		}
 	}

 	if sweepClosure == nil {
-		return nil, 0, fmt.Errorf("sweep closure not found")
+		return nil, nil, fmt.Errorf("sweep closure not found")
 	}

-	return sweepClosure, seconds, nil
+	return sweepClosure, locktime, nil
 }
--- a/pkg/client-sdk/store/file/config_store.go
+++ b/pkg/client-sdk/store/file/config_store.go
@@ -57,9 +57,9 @@ func (s *configStore) AddData(ctx context.Context, data types.Config) error {
 		WalletType:                 data.WalletType,
 		ClientType:                 data.ClientType,
 		Network:                    data.Network.Name,
-		RoundLifetime:              fmt.Sprintf("%d", data.RoundLifetime),
+		RoundLifetime:              fmt.Sprintf("%d", data.RoundLifetime.Value),
 		RoundInterval:              fmt.Sprintf("%d", data.RoundInterval),
-		UnilateralExitDelay:        fmt.Sprintf("%d", data.UnilateralExitDelay),
+		UnilateralExitDelay:        fmt.Sprintf("%d", data.UnilateralExitDelay.Value),
 		Dust:                       fmt.Sprintf("%d", data.Dust),
 		BoardingDescriptorTemplate: data.BoardingDescriptorTemplate,
 		ExplorerURL:                data.ExplorerURL,
--- a/pkg/client-sdk/store/file/types.go
+++ b/pkg/client-sdk/store/file/types.go
@@ -4,6 +4,7 @@ import (
 	"encoding/hex"
 	"strconv"

+	"github.com/ark-network/ark/common"
 	"github.com/ark-network/ark/pkg/client-sdk/internal/utils"
 	"github.com/ark-network/ark/pkg/client-sdk/types"
 	"github.com/decred/dcrd/dcrec/secp256k1/v4"
@@ -44,14 +45,25 @@ func (d storeData) decode() types.Config {
 	buf, _ := hex.DecodeString(d.ServerPubKey)
 	serverPubkey, _ := secp256k1.ParsePubKey(buf)
 	explorerURL := d.ExplorerURL
+
+	lifetimeType := common.LocktimeTypeBlock
+	if roundLifetime >= 512 {
+		lifetimeType = common.LocktimeTypeSecond
+	}
+
+	unilateralExitDelayType := common.LocktimeTypeBlock
+	if unilateralExitDelay >= 512 {
+		unilateralExitDelayType = common.LocktimeTypeSecond
+	}
+
 	return types.Config{
 		ServerUrl:                  d.ServerUrl,
 		ServerPubKey:               serverPubkey,
 		WalletType:                 d.WalletType,
 		ClientType:                 d.ClientType,
 		Network:                    network,
-		RoundLifetime:              int64(roundLifetime),
-		UnilateralExitDelay:        int64(unilateralExitDelay),
+		RoundLifetime:              common.Locktime{Type: lifetimeType, Value: uint32(roundLifetime)},
+		UnilateralExitDelay:        common.Locktime{Type: unilateralExitDelayType, Value: uint32(unilateralExitDelay)},
 		RoundInterval:              int64(roundInterval),
 		Dust:                       uint64(dust),
 		BoardingDescriptorTemplate: d.BoardingDescriptorTemplate,
--- a/pkg/client-sdk/store/service_test.go
+++ b/pkg/client-sdk/store/service_test.go
@@ -26,9 +26,9 @@ func TestStore(t *testing.T) {
 		WalletType:                 wallet.SingleKeyWallet,
 		ClientType:                 client.GrpcClient,
 		Network:                    common.LiquidRegTest,
-		RoundLifetime:              512,
+		RoundLifetime:              common.Locktime{Type: common.LocktimeTypeSecond, Value: 512},
 		RoundInterval:              10,
-		UnilateralExitDelay:        512,
+		UnilateralExitDelay:        common.Locktime{Type: common.LocktimeTypeSecond, Value: 512},
 		Dust:                       1000,
 		BoardingDescriptorTemplate: "tr(0250929b74c1a04954b78b4b6035e97a5e078a5a0f28ec96d547bfee9ace803ac0,{ and(pk(873079a0091c9b16abd1f8c508320b07f0d50144d09ccd792ce9c915dac60465), pk(USER)), and(older(604672), pk(USER)) })",
 		ForfeitAddress:             "bcrt1qzvqj",
--- a/pkg/client-sdk/types/types.go
+++ b/pkg/client-sdk/types/types.go
@@ -21,9 +21,9 @@ type Config struct {
 	WalletType                 string
 	ClientType                 string
 	Network                    common.Network
-	RoundLifetime              int64
+	RoundLifetime              common.Locktime
 	RoundInterval              int64
-	UnilateralExitDelay        int64
+	UnilateralExitDelay        common.Locktime
 	Dust                       uint64
 	BoardingDescriptorTemplate string
 	ExplorerURL                string
@@ -110,7 +110,7 @@ type Utxo struct {
 	VOut        uint32
 	Amount      uint64
 	Asset       string // liquid only
-	Delay       uint
+	Delay       common.Locktime
 	SpendableAt time.Time
 	CreatedAt   time.Time
 	Tapscripts  []string
--- a/pkg/client-sdk/wallet/singlekey/bitcoin_wallet.go
+++ b/pkg/client-sdk/wallet/singlekey/bitcoin_wallet.go
@@ -220,6 +220,13 @@ func (s *bitcoinWallet) SignTransaction(
 							break
 						}
 					}
+				case *tree.CLTVMultisigClosure:
+					for _, key := range c.MultisigClosure.PubKeys {
+						if bytes.Equal(schnorr.SerializePubKey(key), myPubkey) {
+							sign = true
+							break
+						}
+					}
 				}

 				if sign {
@@ -310,7 +317,7 @@ func (w *bitcoinWallet) getAddress(
 	defaultVtxoScript := bitcointree.NewDefaultVtxoScript(
 		w.walletData.PubKey,
 		data.ServerPubKey,
-		uint(data.UnilateralExitDelay),
+		data.UnilateralExitDelay,
 	)

 	vtxoTapKey, _, err := defaultVtxoScript.TapTree()
@@ -327,7 +334,10 @@ func (w *bitcoinWallet) getAddress(
 	boardingVtxoScript := bitcointree.NewDefaultVtxoScript(
 		w.walletData.PubKey,
 		data.ServerPubKey,
-		uint(data.UnilateralExitDelay*2),
+		common.Locktime{
+			Type:  data.UnilateralExitDelay.Type,
+			Value: data.UnilateralExitDelay.Value * 2,
+		},
 	)

 	boardingTapKey, _, err := boardingVtxoScript.TapTree()
--- a/pkg/client-sdk/wallet/singlekey/liquid_wallet.go
+++ b/pkg/client-sdk/wallet/singlekey/liquid_wallet.go
@@ -242,6 +242,13 @@ func (s *liquidWallet) SignTransaction(
 							break
 						}
 					}
+				case *tree.CLTVMultisigClosure:
+					for _, key := range c.MultisigClosure.PubKeys {
+						if bytes.Equal(schnorr.SerializePubKey(key), myPubkey) {
+							sign = true
+							break
+						}
+					}
 				}

 				if sign {
@@ -332,7 +339,7 @@ func (w *liquidWallet) getAddress(
 	vtxoScript := tree.NewDefaultVtxoScript(
 		w.walletData.PubKey,
 		data.ServerPubKey,
-		uint(data.UnilateralExitDelay),
+		data.UnilateralExitDelay,
 	)

 	vtxoTapKey, _, err := vtxoScript.TapTree()
@@ -349,7 +356,10 @@ func (w *liquidWallet) getAddress(
 	boardingVtxoScript := tree.NewDefaultVtxoScript(
 		w.walletData.PubKey,
 		data.ServerPubKey,
-		uint(data.UnilateralExitDelay*2),
+		common.Locktime{
+			Type:  data.UnilateralExitDelay.Type,
+			Value: data.UnilateralExitDelay.Value * 2,
+		},
 	)

 	boardingTapKey, _, err := boardingVtxoScript.TapTree()
--- a/pkg/client-sdk/wallet/wallet_test.go
+++ b/pkg/client-sdk/wallet/wallet_test.go
@@ -26,9 +26,9 @@ func TestWallet(t *testing.T) {
 		WalletType:                 wallet.SingleKeyWallet,
 		ClientType:                 client.GrpcClient,
 		Network:                    common.LiquidRegTest,
-		RoundLifetime:              512,
+		RoundLifetime:              common.Locktime{Type: common.LocktimeTypeSecond, Value: 512},
 		RoundInterval:              10,
-		UnilateralExitDelay:        512,
+		UnilateralExitDelay:        common.Locktime{Type: common.LocktimeTypeSecond, Value: 512},
 		Dust:                       1000,
 		BoardingDescriptorTemplate: "tr(0250929b74c1a04954b78b4b6035e97a5e078a5a0f28ec96d547bfee9ace803ac0,{ and(pk(873079a0091c9b16abd1f8c508320b07f0d50144d09ccd792ce9c915dac60465), pk(USER)), and(older(604672), pk(USER)) })",
 		ForfeitAddress:             "bcrt1qzvqj",
--- a/pkg/client-sdk/wasm/browser/config_store.go
+++ b/pkg/client-sdk/wasm/browser/config_store.go
@@ -11,6 +11,7 @@ import (
 	"strconv"
 	"syscall/js"

+	"github.com/ark-network/ark/common"
 	"github.com/ark-network/ark/pkg/client-sdk/internal/utils"
 	"github.com/ark-network/ark/pkg/client-sdk/types"
 	"github.com/decred/dcrd/dcrec/secp256k1/v4"
@@ -59,9 +60,9 @@ func (s *configStore) AddData(ctx context.Context, data types.Config) error {
 		WalletType:                 data.WalletType,
 		ClientType:                 data.ClientType,
 		Network:                    data.Network.Name,
-		RoundLifetime:              fmt.Sprintf("%d", data.RoundLifetime),
+		RoundLifetime:              fmt.Sprintf("%d", data.RoundLifetime.Value),
 		RoundInterval:              fmt.Sprintf("%d", data.RoundInterval),
-		UnilateralExitDelay:        fmt.Sprintf("%d", data.UnilateralExitDelay),
+		UnilateralExitDelay:        fmt.Sprintf("%d", data.UnilateralExitDelay.Value),
 		Dust:                       fmt.Sprintf("%d", data.Dust),
 		ExplorerURL:                data.ExplorerURL,
 		ForfeitAddress:             data.ForfeitAddress,
@@ -94,15 +95,25 @@ func (s *configStore) GetData(ctx context.Context) (*types.Config, error) {
 	dust, _ := strconv.Atoi(s.store.Call("getItem", "dust").String())
 	withTxFeed, _ := strconv.ParseBool(s.store.Call("getItem", "with_transaction_feed").String())

+	lifetimeType := common.LocktimeTypeBlock
+	if roundLifetime >= 512 {
+		lifetimeType = common.LocktimeTypeSecond
+	}
+
+	unilateralExitDelayType := common.LocktimeTypeBlock
+	if unilateralExitDelay >= 512 {
+		unilateralExitDelayType = common.LocktimeTypeSecond
+	}
+
 	return &types.Config{
 		ServerUrl:                  s.store.Call("getItem", "server_url").String(),
 		ServerPubKey:               serverPubkey,
 		WalletType:                 s.store.Call("getItem", "wallet_type").String(),
 		ClientType:                 s.store.Call("getItem", "client_type").String(),
 		Network:                    network,
-		RoundLifetime:              int64(roundLifetime),
+		RoundLifetime:              common.Locktime{Value: uint32(roundLifetime), Type: lifetimeType},
 		RoundInterval:              int64(roundInterval),
-		UnilateralExitDelay:        int64(unilateralExitDelay),
+		UnilateralExitDelay:        common.Locktime{Value: uint32(unilateralExitDelay), Type: unilateralExitDelayType},
 		Dust:                       uint64(dust),
 		ExplorerURL:                s.store.Call("getItem", "explorer_url").String(),
 		ForfeitAddress:             s.store.Call("getItem", "forfeit_address").String(),
--- a/pkg/client-sdk/wasm/browser/wrappers.go
+++ b/pkg/client-sdk/wasm/browser/wrappers.go
@@ -374,7 +374,7 @@ func GetRoundLifetimeWrapper() js.Func {
 		data, _ := arkSdkClient.GetConfigData(context.Background())
 		var roundLifettime int64
 		if data != nil {
-			roundLifettime = data.RoundLifetime
+			roundLifettime = data.RoundLifetime.Seconds()
 		}
 		return js.ValueOf(roundLifettime)
 	})
@@ -385,7 +385,7 @@ func GetUnilateralExitDelayWrapper() js.Func {
 		data, _ := arkSdkClient.GetConfigData(context.Background())
 		var unilateralExitDelay int64
 		if data != nil {
-			unilateralExitDelay = data.UnilateralExitDelay
+			unilateralExitDelay = data.UnilateralExitDelay.Seconds()
 		}
 		return js.ValueOf(unilateralExitDelay)
 	})
--- a/server/cmd/arkd/main.go
+++ b/server/cmd/arkd/main.go
@@ -59,6 +59,17 @@ func mainAction(_ *cli.Context) error {
 		TLSExtraDomains: cfg.TLSExtraDomains,
 	}

+	lifetimeType, unilateralExitType, boardingExitType := common.LocktimeTypeBlock, common.LocktimeTypeBlock, common.LocktimeTypeBlock
+	if cfg.RoundLifetime >= 512 {
+		lifetimeType = common.LocktimeTypeSecond
+	}
+	if cfg.UnilateralExitDelay >= 512 {
+		unilateralExitType = common.LocktimeTypeSecond
+	}
+	if cfg.BoardingExitDelay >= 512 {
+		boardingExitType = common.LocktimeTypeSecond
+	}
+
 	appConfig := &appconfig.Config{
 		EventDbType:             cfg.EventDbType,
 		DbType:                  cfg.DbType,
@@ -70,8 +81,8 @@ func mainAction(_ *cli.Context) error {
 		SchedulerType:           cfg.SchedulerType,
 		TxBuilderType:           cfg.TxBuilderType,
 		WalletAddr:              cfg.WalletAddr,
-		RoundLifetime:           cfg.RoundLifetime,
-		UnilateralExitDelay:     cfg.UnilateralExitDelay,
+		RoundLifetime:           common.Locktime{Type: lifetimeType, Value: uint32(cfg.RoundLifetime)},
+		UnilateralExitDelay:     common.Locktime{Type: unilateralExitType, Value: uint32(cfg.UnilateralExitDelay)},
 		EsploraURL:              cfg.EsploraURL,
 		NeutrinoPeer:            cfg.NeutrinoPeer,
 		BitcoindRpcUser:         cfg.BitcoindRpcUser,
@@ -79,7 +90,7 @@ func mainAction(_ *cli.Context) error {
 		BitcoindRpcHost:         cfg.BitcoindRpcHost,
 		BitcoindZMQBlock:        cfg.BitcoindZMQBlock,
 		BitcoindZMQTx:           cfg.BitcoindZMQTx,
-		BoardingExitDelay:       cfg.BoardingExitDelay,
+		BoardingExitDelay:       common.Locktime{Type: boardingExitType, Value: uint32(cfg.BoardingExitDelay)},
 		UnlockerType:            cfg.UnlockerType,
 		UnlockerFilePath:        cfg.UnlockerFilePath,
 		UnlockerPassword:        cfg.UnlockerPassword,
--- a/server/internal/app-config/config.go
+++ b/server/internal/app-config/config.go
@@ -65,9 +65,9 @@ type Config struct {
 	SchedulerType           string
 	TxBuilderType           string
 	WalletAddr              string
-	RoundLifetime           int64
-	UnilateralExitDelay     int64
-	BoardingExitDelay       int64
+	RoundLifetime           common.Locktime
+	UnilateralExitDelay     common.Locktime
+	BoardingExitDelay       common.Locktime
 	NostrDefaultRelays      []string
 	NoteUriPrefix           string
 	MarketHourStartTime     time.Time
@@ -119,18 +119,18 @@ func (c *Config) Validate() error {
 	if !supportedNetworks.supports(c.Network.Name) {
 		return fmt.Errorf("invalid network, must be one of: %s", supportedNetworks)
 	}
-	if c.RoundLifetime < minAllowedSequence {
+	if c.RoundLifetime.Type == common.LocktimeTypeBlock {
 		if c.SchedulerType != "block" {
 			return fmt.Errorf("scheduler type must be block if round lifetime is expressed in blocks")
 		}
-	} else {
+	} else { // seconds
 		if c.SchedulerType != "gocron" {
 			return fmt.Errorf("scheduler type must be gocron if round lifetime is expressed in seconds")
 		}

 		// round life time must be a multiple of 512 if expressed in seconds
-		if c.RoundLifetime%minAllowedSequence != 0 {
-			c.RoundLifetime -= c.RoundLifetime % minAllowedSequence
+		if c.RoundLifetime.Value%minAllowedSequence != 0 {
+			c.RoundLifetime.Value -= c.RoundLifetime.Value % minAllowedSequence
 			log.Infof(
 				"round lifetime must be a multiple of %d, rounded to %d",
 				minAllowedSequence, c.RoundLifetime,
@@ -138,28 +138,28 @@ func (c *Config) Validate() error {
 		}
 	}

-	if c.UnilateralExitDelay < minAllowedSequence {
+	if c.UnilateralExitDelay.Type == common.LocktimeTypeBlock {
 		return fmt.Errorf(
 			"invalid unilateral exit delay, must at least %d", minAllowedSequence,
 		)
 	}

-	if c.BoardingExitDelay < minAllowedSequence {
+	if c.BoardingExitDelay.Type == common.LocktimeTypeBlock {
 		return fmt.Errorf(
 			"invalid boarding exit delay, must at least %d", minAllowedSequence,
 		)
 	}

-	if c.UnilateralExitDelay%minAllowedSequence != 0 {
-		c.UnilateralExitDelay -= c.UnilateralExitDelay % minAllowedSequence
+	if c.UnilateralExitDelay.Value%minAllowedSequence != 0 {
+		c.UnilateralExitDelay.Value -= c.UnilateralExitDelay.Value % minAllowedSequence
 		log.Infof(
 			"unilateral exit delay must be a multiple of %d, rounded to %d",
 			minAllowedSequence, c.UnilateralExitDelay,
 		)
 	}

-	if c.BoardingExitDelay%minAllowedSequence != 0 {
-		c.BoardingExitDelay -= c.BoardingExitDelay % minAllowedSequence
+	if c.BoardingExitDelay.Value%minAllowedSequence != 0 {
+		c.BoardingExitDelay.Value -= c.BoardingExitDelay.Value % minAllowedSequence
 		log.Infof(
 			"boarding exit delay must be a multiple of %d, rounded to %d",
 			minAllowedSequence, c.BoardingExitDelay,
@@ -260,7 +260,7 @@ func (c *Config) repoManager() error {

 func (c *Config) walletService() error {
 	if common.IsLiquid(c.Network) {
-		svc, err := liquidwallet.NewService(c.WalletAddr)
+		svc, err := liquidwallet.NewService(c.WalletAddr, c.EsploraURL)
 		if err != nil {
 			return fmt.Errorf("failed to connect to wallet: %s", err)
 		}
@@ -384,7 +384,7 @@ func (c *Config) appService() error {

 func (c *Config) adminService() error {
 	unit := ports.UnixTime
-	if c.RoundLifetime < minAllowedSequence {
+	if c.RoundLifetime.Value < minAllowedSequence {
 		unit = ports.BlockHeight
 	}

--- a/server/internal/core/application/covenant.go
+++ b/server/internal/core/application/covenant.go
@@ -31,10 +31,10 @@ var (
 type covenantService struct {
 	network             common.Network
 	pubkey              *secp256k1.PublicKey
-	roundLifetime       int64
 	roundInterval       int64
-	unilateralExitDelay int64
-	boardingExitDelay   int64
+	roundLifetime       common.Locktime
+	unilateralExitDelay common.Locktime
+	boardingExitDelay   common.Locktime

 	nostrDefaultRelays []string

@@ -57,7 +57,8 @@ type covenantService struct {

 func NewCovenantService(
 	network common.Network,
-	roundInterval, roundLifetime, unilateralExitDelay, boardingExitDelay int64,
+	roundInterval int64,
+	roundLifetime, unilateralExitDelay, boardingExitDelay common.Locktime,
 	nostrDefaultRelays []string,
 	walletSvc ports.WalletService, repoManager ports.RepoManager,
 	builder ports.TxBuilder, scanner ports.BlockchainScanner,
@@ -162,7 +163,7 @@ func (s *covenantService) Stop() {
 }

 func (s *covenantService) GetBoardingAddress(ctx context.Context, userPubkey *secp256k1.PublicKey) (string, []string, error) {
-	vtxoScript := tree.NewDefaultVtxoScript(userPubkey, s.pubkey, uint(s.boardingExitDelay))
+	vtxoScript := tree.NewDefaultVtxoScript(userPubkey, s.pubkey, s.boardingExitDelay)

 	tapKey, _, err := vtxoScript.TapTree()
 	if err != nil {
@@ -235,7 +236,7 @@ func (s *covenantService) SpendVtxos(ctx context.Context, inputs []ports.Input)
 				}

 				// if the exit path is available, forbid registering the boarding utxo
-				if blocktime+int64(exitDelay) < now {
+				if blocktime+exitDelay.Seconds() < now {
 					return "", fmt.Errorf("tx %s expired", input.Txid)
 				}

@@ -332,7 +333,7 @@ func (s *covenantService) newBoardingInput(tx *transaction.Transaction, input po
 		return nil, fmt.Errorf("descriptor does not match script in transaction output")
 	}

-	if err := boardingScript.Validate(s.pubkey, uint(s.unilateralExitDelay)); err != nil {
+	if err := boardingScript.Validate(s.pubkey, s.unilateralExitDelay); err != nil {
 		return nil, err
 	}

@@ -457,8 +458,8 @@ func (s *covenantService) GetInfo(ctx context.Context) (*ServiceInfo, error) {

 	return &ServiceInfo{
 		PubKey:              pubkey,
-		RoundLifetime:       s.roundLifetime,
-		UnilateralExitDelay: s.unilateralExitDelay,
+		RoundLifetime:       int64(s.roundLifetime.Value),
+		UnilateralExitDelay: int64(s.unilateralExitDelay.Value),
 		RoundInterval:       s.roundInterval,
 		Network:             s.network.Name,
 		Dust:                dust,
@@ -1003,7 +1004,7 @@ func (s *covenantService) scheduleSweepVtxosForRound(round *domain.Round) {
 		return
 	}

-	expirationTime := s.sweeper.scheduler.AddNow(s.roundLifetime)
+	expirationTime := s.sweeper.scheduler.AddNow(int64(s.roundLifetime.Value))

 	if err := s.sweeper.schedule(
 		expirationTime, round.Txid, round.VtxoTree,
--- a/server/internal/core/application/covenantless.go
+++ b/server/internal/core/application/covenantless.go
@@ -33,10 +33,10 @@ const marketHourDelta = 5 * time.Minute
 type covenantlessService struct {
 	network             common.Network
 	pubkey              *secp256k1.PublicKey
-	roundLifetime       int64
+	roundLifetime       common.Locktime
 	roundInterval       int64
-	unilateralExitDelay int64
-	boardingExitDelay   int64
+	unilateralExitDelay common.Locktime
+	boardingExitDelay   common.Locktime

 	nostrDefaultRelays []string

@@ -61,7 +61,8 @@ type covenantlessService struct {

 func NewCovenantlessService(
 	network common.Network,
-	roundInterval, roundLifetime, unilateralExitDelay, boardingExitDelay int64,
+	roundInterval int64,
+	roundLifetime, unilateralExitDelay, boardingExitDelay common.Locktime,
 	nostrDefaultRelays []string,
 	walletSvc ports.WalletService, repoManager ports.RepoManager,
 	builder ports.TxBuilder, scanner ports.BlockchainScanner,
@@ -303,6 +304,35 @@ func (s *covenantlessService) SubmitRedeemTx(
 			return "", fmt.Errorf("witness utxo value mismatch")
 		}

+		// verify forfeit closure script
+		closure, err := tree.DecodeClosure(tapscript.Script)
+		if err != nil {
+			return "", fmt.Errorf("failed to decode forfeit closure: %s", err)
+		}
+
+		switch c := closure.(type) {
+		case *tree.CLTVMultisigClosure:
+			blocktimestamp, err := s.wallet.GetCurrentBlockTime(ctx)
+			if err != nil {
+				return "", fmt.Errorf("failed to get current block time: %s", err)
+			}
+
+			switch c.Locktime.Type {
+			case common.LocktimeTypeBlock:
+				if c.Locktime.Value > blocktimestamp.Height {
+					return "", fmt.Errorf("forfeit closure is CLTV locked, %d > %d (block height)", c.Locktime.Value, blocktimestamp.Height)
+				}
+			case common.LocktimeTypeSecond:
+				if c.Locktime.Value > uint32(blocktimestamp.Time) {
+					return "", fmt.Errorf("forfeit closure is CLTV locked, %d > %d (block time)", c.Locktime.Value, blocktimestamp.Time)
+				}
+			}
+		case *tree.MultisigClosure:
+			// prevent failure in case of multisig closure
+		default:
+			return "", fmt.Errorf("invalid forfeit closure script")
+		}
+
 		ctrlBlock, err := txscript.ParseControlBlock(tapscript.ControlBlock)
 		if err != nil {
 			return "", fmt.Errorf("failed to parse control block: %s", err)
@@ -349,7 +379,7 @@ func (s *covenantlessService) SubmitRedeemTx(
 	}

 	// recompute redeem tx
-	rebuiltRedeemTx, err := bitcointree.BuildRedeemTx(ins, outputs, fees)
+	rebuiltRedeemTx, err := bitcointree.BuildRedeemTx(ins, outputs)
 	if err != nil {
 		return "", fmt.Errorf("failed to rebuild redeem tx: %s", err)
 	}
@@ -439,7 +469,7 @@ func (s *covenantlessService) SubmitRedeemTx(
 func (s *covenantlessService) GetBoardingAddress(
 	ctx context.Context, userPubkey *secp256k1.PublicKey,
 ) (address string, scripts []string, err error) {
-	vtxoScript := bitcointree.NewDefaultVtxoScript(s.pubkey, userPubkey, uint(s.boardingExitDelay))
+	vtxoScript := bitcointree.NewDefaultVtxoScript(s.pubkey, userPubkey, s.boardingExitDelay)

 	tapKey, _, err := vtxoScript.TapTree()
 	if err != nil {
@@ -546,7 +576,7 @@ func (s *covenantlessService) SpendVtxos(ctx context.Context, inputs []ports.Inp
 				}

 				// if the exit path is available, forbid registering the boarding utxo
-				if blocktime+int64(exitDelay) < now {
+				if blocktime+exitDelay.Seconds() < now {
 					return "", fmt.Errorf("tx %s expired", input.Txid)
 				}

@@ -634,7 +664,7 @@ func (s *covenantlessService) newBoardingInput(tx wire.MsgTx, input ports.Input)
 		return nil, fmt.Errorf("descriptor does not match script in transaction output")
 	}

-	if err := boardingScript.Validate(s.pubkey, uint(s.unilateralExitDelay)); err != nil {
+	if err := boardingScript.Validate(s.pubkey, s.unilateralExitDelay); err != nil {
 		return nil, err
 	}

@@ -755,8 +785,8 @@ func (s *covenantlessService) GetInfo(ctx context.Context) (*ServiceInfo, error)

 	return &ServiceInfo{
 		PubKey:              pubkey,
-		RoundLifetime:       s.roundLifetime,
-		UnilateralExitDelay: s.unilateralExitDelay,
+		RoundLifetime:       int64(s.roundLifetime.Value),
+		UnilateralExitDelay: int64(s.unilateralExitDelay.Value),
 		RoundInterval:       s.roundInterval,
 		Network:             s.network.Name,
 		Dust:                dust,
@@ -1064,7 +1094,7 @@ func (s *covenantlessService) startFinalization() {

 		sweepClosure := tree.CSVSigClosure{
 			MultisigClosure: tree.MultisigClosure{PubKeys: []*secp256k1.PublicKey{s.pubkey}},
-			Seconds:         uint(s.roundLifetime),
+			Locktime:        s.roundLifetime,
 		}

 		sweepScript, err := sweepClosure.Script()
@@ -1561,7 +1591,7 @@ func (s *covenantlessService) scheduleSweepVtxosForRound(round *domain.Round) {
 		return
 	}

-	expirationTimestamp := s.sweeper.scheduler.AddNow(s.roundLifetime)
+	expirationTimestamp := s.sweeper.scheduler.AddNow(int64(s.roundLifetime.Value))

 	if err := s.sweeper.schedule(expirationTimestamp, round.Txid, round.VtxoTree); err != nil {
 		log.WithError(err).Warn("failed to schedule sweep tx")
--- a/server/internal/core/application/proof.go
+++ b/server/internal/core/application/proof.go
@@ -65,16 +65,17 @@ func (p OwnershipProof) validate(vtxo domain.Vtxo) error {
 }

 func decodeForfeitClosure(script []byte) ([]*secp256k1.PublicKey, error) {
-	var forfeit tree.MultisigClosure
-
-	valid, err := forfeit.Decode(script)
+	closure, err := tree.DecodeClosure(script)
 	if err != nil {
 		return nil, err
 	}

-	if !valid {
-		return nil, fmt.Errorf("invalid forfeit closure script")
+	switch c := closure.(type) {
+	case *tree.MultisigClosure:
+		return c.PubKeys, nil
+	case *tree.CLTVMultisigClosure:
+		return c.PubKeys, nil
 	}

-	return forfeit.PubKeys, nil
+	return nil, fmt.Errorf("invalid forfeit closure script")
 }
--- a/server/internal/core/application/utils.go
+++ b/server/internal/core/application/utils.go
@@ -7,6 +7,7 @@ import (
 	"sync"
 	"time"

+	"github.com/ark-network/ark/common"
 	"github.com/ark-network/ark/common/note"
 	"github.com/ark-network/ark/common/tree"
 	"github.com/ark-network/ark/server/internal/core/domain"
@@ -357,12 +358,12 @@ func findSweepableOutputs(
 					}
 				}

-				var lifetime int64
+				var lifetime *common.Locktime
 				lifetime, sweepInput, err = txbuilder.GetSweepInput(node)
 				if err != nil {
 					return nil, err
 				}
-				expirationTime = blocktimeCache[node.ParentTxid] + lifetime
+				expirationTime = blocktimeCache[node.ParentTxid] + int64(lifetime.Value)
 			} else {
 				// cache the blocktime for future use
 				if schedulerUnit == ports.BlockHeight {
--- a/server/internal/core/ports/tx_builder.go
+++ b/server/internal/core/ports/tx_builder.go
@@ -1,6 +1,7 @@
 package ports

 import (
+	"github.com/ark-network/ark/common"
 	"github.com/ark-network/ark/common/tree"
 	"github.com/ark-network/ark/server/internal/core/domain"
 	"github.com/btcsuite/btcd/chaincfg/chainhash"
@@ -47,7 +48,7 @@ type TxBuilder interface {
 		txs []string,
 	) (valid map[domain.VtxoKey][]string, err error)
 	BuildSweepTx(inputs []SweepInput) (signedSweepTx string, err error)
-	GetSweepInput(node tree.Node) (lifetime int64, sweepInput SweepInput, err error)
+	GetSweepInput(node tree.Node) (lifetime *common.Locktime, sweepInput SweepInput, err error)
 	FinalizeAndExtract(tx string) (txhex string, err error)
 	VerifyTapscriptPartialSigs(tx string) (valid bool, err error)
 	// FindLeaves returns all the leaves txs that are reachable from the given outpoint
--- a/server/internal/core/ports/wallet.go
+++ b/server/internal/core/ports/wallet.go
@@ -42,6 +42,7 @@ type WalletService interface {
 	GetTransaction(ctx context.Context, txid string) (string, error)
 	SignMessage(ctx context.Context, message []byte) ([]byte, error)
 	VerifyMessageSignature(ctx context.Context, message, signature []byte) (bool, error)
+	GetCurrentBlockTime(ctx context.Context) (*BlockTimestamp, error)
 	Close()
 }

@@ -63,3 +64,8 @@ type TxOutpoint interface {
 	GetTxid() string
 	GetIndex() uint32
 }
+
+type BlockTimestamp struct {
+	Height uint32
+	Time   int64
+}
--- a/server/internal/infrastructure/scheduler/block/service.go
+++ b/server/internal/infrastructure/scheduler/block/service.go
@@ -11,7 +11,7 @@ import (
 	"github.com/sirupsen/logrus"
 )

-const tipHeightEndpoit = "/blocks/tip/height"
+const tipHeightEndpoint = "/blocks/tip/height"

 type service struct {
 	tipURL string
@@ -25,7 +25,7 @@ func NewScheduler(esploraURL string) (ports.SchedulerService, error) {
 		return nil, fmt.Errorf("esplora URL is required")
 	}

-	tipURL, err := url.JoinPath(esploraURL, tipHeightEndpoit)
+	tipURL, err := url.JoinPath(esploraURL, tipHeightEndpoint)
 	if err != nil {
 		return nil, err
 	}
--- a/server/internal/infrastructure/tx-builder/covenant/builder.go
+++ b/server/internal/infrastructure/tx-builder/covenant/builder.go
@@ -28,15 +28,15 @@ import (
 type txBuilder struct {
 	wallet            ports.WalletService
 	net               common.Network
-	roundLifetime     int64 // in seconds
-	boardingExitDelay int64 // in seconds
+	roundLifetime     common.Locktime
+	boardingExitDelay common.Locktime
 }

 func NewTxBuilder(
 	wallet ports.WalletService,
 	net common.Network,
-	roundLifetime int64,
-	boardingExitDelay int64,
+	roundLifetime common.Locktime,
+	boardingExitDelay common.Locktime,
 ) ports.TxBuilder {
 	return &txBuilder{wallet, net, roundLifetime, boardingExitDelay}
 }
@@ -158,6 +158,11 @@ func (b *txBuilder) VerifyForfeitTxs(vtxos []domain.Vtxo, connectors []string, f

 	validForfeitTxs := make(map[domain.VtxoKey][]string)

+	blocktimestamp, err := b.wallet.GetCurrentBlockTime(context.Background())
+	if err != nil {
+		return nil, err
+	}
+
 	for vtxoKey, psets := range forfeitTxsPsets {
 		if len(psets) == 0 {
 			continue
@@ -202,13 +207,36 @@ func (b *txBuilder) VerifyForfeitTxs(vtxos []domain.Vtxo, connectors []string, f

 		vtxoTapscript := firstForfeit.Inputs[1].TapLeafScript[0]

+		// verify the forfeit closure script
+		closure, err := tree.DecodeClosure(vtxoTapscript.Script)
+		if err != nil {
+			return nil, err
+		}
+
+		switch c := closure.(type) {
+		case *tree.CLTVMultisigClosure:
+			switch c.Locktime.Type {
+			case common.LocktimeTypeBlock:
+				if c.Locktime.Value > blocktimestamp.Height {
+					return nil, fmt.Errorf("forfeit closure is CLTV locked, %d > %d (block height)", c.Locktime.Value, blocktimestamp.Height)
+				}
+			case common.LocktimeTypeSecond:
+				if c.Locktime.Value > uint32(blocktimestamp.Time) {
+					return nil, fmt.Errorf("forfeit closure is CLTV locked, %d > %d (block time)", c.Locktime.Value, blocktimestamp.Time)
+				}
+			}
+		case *tree.MultisigClosure:
+		default:
+			return nil, fmt.Errorf("invalid forfeit closure script")
+		}
+
 		minFee, err := common.ComputeForfeitTxFee(
 			minRate,
 			&waddrmgr.Tapscript{
 				RevealedScript: vtxoTapscript.Script,
 				ControlBlock:   &vtxoTapscript.ControlBlock.ControlBlock,
 			},
-			64*2,
+			closure.WitnessSize(),
 			txscript.GetScriptClass(forfeitScript),
 		)
 		if err != nil {
@@ -418,14 +446,14 @@ func (b *txBuilder) BuildRoundTx(
 	return
 }

-func (b *txBuilder) GetSweepInput(node tree.Node) (lifetime int64, sweepInput ports.SweepInput, err error) {
+func (b *txBuilder) GetSweepInput(node tree.Node) (lifetime *common.Locktime, sweepInput ports.SweepInput, err error) {
 	pset, err := psetv2.NewPsetFromBase64(node.Tx)
 	if err != nil {
-		return -1, nil, err
+		return nil, nil, err
 	}

 	if len(pset.Inputs) != 1 {
-		return -1, nil, fmt.Errorf("invalid node pset, expect 1 input, got %d", len(pset.Inputs))
+		return nil, nil, fmt.Errorf("invalid node pset, expect 1 input, got %d", len(pset.Inputs))
 	}

 	// if the tx is not onchain, it means that the input is an existing shared output
@@ -435,22 +463,22 @@ func (b *txBuilder) GetSweepInput(node tree.Node) (lifetime int64, sweepInput po

 	sweepLeaf, lifetime, err := extractSweepLeaf(input)
 	if err != nil {
-		return -1, nil, err
+		return nil, nil, err
 	}

 	txhex, err := b.wallet.GetTransaction(context.Background(), txid)
 	if err != nil {
-		return -1, nil, err
+		return nil, nil, err
 	}

 	tx, err := transaction.NewTxFromHex(txhex)
 	if err != nil {
-		return -1, nil, err
+		return nil, nil, err
 	}

 	inputValue, err := elementsutil.ValueFromBytes(tx.Outputs[index].Value)
 	if err != nil {
-		return -1, nil, err
+		return nil, nil, err
 	}

 	sweepInput = &sweepLiquidInput{
@@ -509,6 +537,10 @@ func (b *txBuilder) verifyTapscriptPartialSigs(pset *psetv2.Pset) (bool, error)
 			for _, key := range c.PubKeys {
 				keys[hex.EncodeToString(schnorr.SerializePubKey(key))] = false
 			}
+		case *tree.CLTVMultisigClosure:
+			for _, key := range c.PubKeys {
+				keys[hex.EncodeToString(schnorr.SerializePubKey(key))] = false
+			}
 		}

 		// we don't need to check if server signed
@@ -1123,24 +1155,24 @@ func (b *txBuilder) onchainNetwork() *network.Network {
 	}
 }

-func extractSweepLeaf(input psetv2.Input) (sweepLeaf *psetv2.TapLeafScript, lifetime int64, err error) {
+func extractSweepLeaf(input psetv2.Input) (sweepLeaf *psetv2.TapLeafScript, lifetime *common.Locktime, err error) {
 	for _, leaf := range input.TapLeafScript {
 		closure := &tree.CSVSigClosure{}
 		valid, err := closure.Decode(leaf.Script)
 		if err != nil {
-			return nil, 0, err
+			return nil, nil, err
 		}
-		if valid && closure.Seconds > uint(lifetime) {
+		if valid && (lifetime == nil || lifetime.LessThan(closure.Locktime)) {
 			sweepLeaf = &leaf
-			lifetime = int64(closure.Seconds)
+			lifetime = &closure.Locktime
 		}
 	}

 	if sweepLeaf == nil {
-		return nil, 0, fmt.Errorf("sweep leaf not found")
+		return nil, nil, fmt.Errorf("sweep leaf not found")
 	}

-	return sweepLeaf, lifetime, nil
+	return
 }

 type sweepLiquidInput struct {
--- a/server/internal/infrastructure/tx-builder/covenant/builder_test.go
+++ b/server/internal/infrastructure/tx-builder/covenant/builder_test.go
@@ -22,14 +22,15 @@ const (
 	connectorAddress = "tex1qekd5u0qj8jl07vy60830xy7n9qtmcx9u3s0cqc"
 	forfeitAddress   = "tex1qekd5u0qj8jl07vy60830xy7n9qtmcx9u3s0cqc"
 	minRelayFee      = uint64(30)
-	roundLifetime     = int64(1209344)
-	boardingExitDelay = int64(512)
 	minRelayFeeRate  = 3
 )

 var (
 	wallet *mockedWallet
 	pubkey *secp256k1.PublicKey
+
+	roundLifetime     = common.Locktime{Type: common.LocktimeTypeSecond, Value: 1209344}
+	boardingExitDelay = common.Locktime{Type: common.LocktimeTypeSecond, Value: 512}
 )

 func TestMain(m *testing.M) {
--- a/server/internal/infrastructure/tx-builder/covenant/mocks_test.go
+++ b/server/internal/infrastructure/tx-builder/covenant/mocks_test.go
@@ -303,6 +303,10 @@ func (m *mockedWallet) VerifyMessageSignature(ctx context.Context, message, sign
 	panic("not implemented")
 }

+func (m *mockedWallet) GetCurrentBlockTime(ctx context.Context) (*ports.BlockTimestamp, error) {
+	panic("not implemented")
+}
+
 type mockedInput struct {
 	mock.Mock
 }
--- a/server/internal/infrastructure/tx-builder/covenant/sweep.go
+++ b/server/internal/infrastructure/tx-builder/covenant/sweep.go
@@ -90,7 +90,7 @@ func sweepTransaction(
 			return nil, err
 		}

-		sequence, err := common.BIP68Sequence(sweepClosure.Seconds)
+		sequence, err := common.BIP68Sequence(sweepClosure.Locktime)
 		if err != nil {
 			return nil, err
 		}
--- a/server/internal/infrastructure/tx-builder/covenantless/builder.go
+++ b/server/internal/infrastructure/tx-builder/covenantless/builder.go
@@ -27,12 +27,12 @@ import (
 type txBuilder struct {
 	wallet            ports.WalletService
 	net               common.Network
-	roundLifetime     int64 // in seconds
-	boardingExitDelay int64 // in seconds
+	roundLifetime     common.Locktime
+	boardingExitDelay common.Locktime
 }

 func NewTxBuilder(
-	wallet ports.WalletService, net common.Network, roundLifetime, boardingExitDelay int64,
+	wallet ports.WalletService, net common.Network, roundLifetime, boardingExitDelay common.Locktime,
 ) ports.TxBuilder {
 	return &txBuilder{wallet, net, roundLifetime, boardingExitDelay}
 }
@@ -91,6 +91,10 @@ func (b *txBuilder) verifyTapscriptPartialSigs(ptx *psbt.Packet) (bool, error) {
 			for _, key := range c.PubKeys {
 				keys[hex.EncodeToString(schnorr.SerializePubKey(key))] = false
 			}
+		case *tree.CLTVMultisigClosure:
+			for _, key := range c.PubKeys {
+				keys[hex.EncodeToString(schnorr.SerializePubKey(key))] = false
+			}
 		}

 		// we don't need to check if server signed
@@ -326,6 +330,11 @@ func (b *txBuilder) VerifyForfeitTxs(vtxos []domain.Vtxo, connectors []string, f

 	validForfeitTxs := make(map[domain.VtxoKey][]string)

+	blocktimestamp, err := b.wallet.GetCurrentBlockTime(context.Background())
+	if err != nil {
+		return nil, err
+	}
+
 	for vtxoKey, ptxs := range forfeitTxsPtxs {
 		if len(ptxs) == 0 {
 			continue
@@ -359,6 +368,30 @@ func (b *txBuilder) VerifyForfeitTxs(vtxos []domain.Vtxo, connectors []string, f
 		}

 		vtxoTapscript := firstForfeit.Inputs[1].TaprootLeafScript[0]
+
+		// verify the forfeit closure script
+		closure, err := tree.DecodeClosure(vtxoTapscript.Script)
+		if err != nil {
+			return nil, err
+		}
+
+		switch c := closure.(type) {
+		case *tree.CLTVMultisigClosure:
+			switch c.Locktime.Type {
+			case common.LocktimeTypeBlock:
+				if c.Locktime.Value > blocktimestamp.Height {
+					return nil, fmt.Errorf("forfeit closure is CLTV locked, %d > %d (block height)", c.Locktime.Value, blocktimestamp.Height)
+				}
+			case common.LocktimeTypeSecond:
+				if c.Locktime.Value > uint32(blocktimestamp.Time) {
+					return nil, fmt.Errorf("forfeit closure is CLTV locked, %d > %d (block time)", c.Locktime.Value, blocktimestamp.Time)
+				}
+			}
+		case *tree.MultisigClosure:
+		default:
+			return nil, fmt.Errorf("invalid forfeit closure script")
+		}
+
 		ctrlBlock, err := txscript.ParseControlBlock(vtxoTapscript.ControlBlock)
 		if err != nil {
 			return nil, err
@@ -370,7 +403,7 @@ func (b *txBuilder) VerifyForfeitTxs(vtxos []domain.Vtxo, connectors []string, f
 				RevealedScript: vtxoTapscript.Script,
 				ControlBlock:   ctrlBlock,
 			},
-			64*2,
+			closure.WitnessSize(),
 			txscript.GetScriptClass(forfeitScript),
 		)
 		if err != nil {
@@ -569,14 +602,14 @@ func (b *txBuilder) BuildRoundTx(
 	return roundTx, vtxoTree, connectorAddress, connectors, nil
 }

-func (b *txBuilder) GetSweepInput(node tree.Node) (lifetime int64, sweepInput ports.SweepInput, err error) {
+func (b *txBuilder) GetSweepInput(node tree.Node) (lifetime *common.Locktime, sweepInput ports.SweepInput, err error) {
 	partialTx, err := psbt.NewFromRawBytes(strings.NewReader(node.Tx), true)
 	if err != nil {
-		return -1, nil, err
+		return nil, nil, err
 	}

 	if len(partialTx.Inputs) != 1 {
-		return -1, nil, fmt.Errorf("invalid node pset, expect 1 input, got %d", len(partialTx.Inputs))
+		return nil, nil, fmt.Errorf("invalid node pset, expect 1 input, got %d", len(partialTx.Inputs))
 	}

 	input := partialTx.UnsignedTx.TxIn[0]
@@ -585,17 +618,17 @@ func (b *txBuilder) GetSweepInput(node tree.Node) (lifetime int64, sweepInput po

 	sweepLeaf, internalKey, lifetime, err := extractSweepLeaf(partialTx.Inputs[0])
 	if err != nil {
-		return -1, nil, err
+		return nil, nil, err
 	}

 	txhex, err := b.wallet.GetTransaction(context.Background(), txid.String())
 	if err != nil {
-		return -1, nil, err
+		return nil, nil, err
 	}

 	var tx wire.MsgTx
 	if err := tx.Deserialize(hex.NewDecoder(strings.NewReader(txhex))); err != nil {
-		return -1, nil, err
+		return nil, nil, err
 	}

 	sweepInput = &sweepBitcoinInput{
@@ -1180,27 +1213,27 @@ func castToOutpoints(inputs []ports.TxInput) []ports.TxOutpoint {
 	return outpoints
 }

-func extractSweepLeaf(input psbt.PInput) (sweepLeaf *psbt.TaprootTapLeafScript, internalKey *secp256k1.PublicKey, lifetime int64, err error) {
+func extractSweepLeaf(input psbt.PInput) (sweepLeaf *psbt.TaprootTapLeafScript, internalKey *secp256k1.PublicKey, lifetime *common.Locktime, err error) {
 	for _, leaf := range input.TaprootLeafScript {
 		closure := &tree.CSVSigClosure{}
 		valid, err := closure.Decode(leaf.Script)
 		if err != nil {
-			return nil, nil, 0, err
+			return nil, nil, nil, err
 		}

-		if valid && closure.Seconds > 0 {
+		if valid && (lifetime == nil || closure.Locktime.LessThan(*lifetime)) {
 			sweepLeaf = leaf
-			lifetime = int64(closure.Seconds)
+			lifetime = &closure.Locktime
 		}
 	}

 	internalKey, err = schnorr.ParsePubKey(input.TaprootInternalKey)
 	if err != nil {
-		return nil, nil, 0, err
+		return nil, nil, nil, err
 	}

 	if sweepLeaf == nil {
-		return nil, nil, 0, fmt.Errorf("sweep leaf not found")
+		return nil, nil, nil, fmt.Errorf("sweep leaf not found")
 	}

 	return sweepLeaf, internalKey, lifetime, nil
--- a/server/internal/infrastructure/tx-builder/covenantless/builder_test.go
+++ b/server/internal/infrastructure/tx-builder/covenantless/builder_test.go
@@ -22,14 +22,15 @@ const (
 	connectorAddress = "bc1py00yhcjpcj0k0sqra0etq0u3yy0purmspppsw0shyzyfe8c83tmq5h6kc2"
 	forfeitAddress   = "bc1py00yhcjpcj0k0sqra0etq0u3yy0purmspppsw0shyzyfe8c83tmq5h6kc2"
 	changeAddress    = "bcrt1qhhq55mut9easvrncy4se8q6vg3crlug7yj4j56"
-	roundLifetime     = int64(1209344)
-	boardingExitDelay = int64(512)
 	minRelayFeeRate  = 3
 )

 var (
 	wallet *mockedWallet
 	pubkey *secp256k1.PublicKey
+
+	roundLifetime     = common.Locktime{Type: common.LocktimeTypeSecond, Value: 1209344}
+	boardingExitDelay = common.Locktime{Type: common.LocktimeTypeSecond, Value: 512}
 )

 func TestMain(m *testing.M) {
--- a/server/internal/infrastructure/tx-builder/covenantless/mocks_test.go
+++ b/server/internal/infrastructure/tx-builder/covenantless/mocks_test.go
@@ -284,6 +284,10 @@ func (m *mockedWallet) MainAccountBalance(ctx context.Context) (uint64, uint64,
 	panic("not implemented")
 }

+func (m *mockedWallet) GetCurrentBlockTime(ctx context.Context) (*ports.BlockTimestamp, error) {
+	panic("not implemented")
+}
+
 type mockedInput struct {
 	mock.Mock
 }
--- a/server/internal/infrastructure/tx-builder/covenantless/sweep.go
+++ b/server/internal/infrastructure/tx-builder/covenantless/sweep.go
@@ -37,7 +37,7 @@ func sweepTransaction(
 			return nil, fmt.Errorf("invalid csv script")
 		}

-		sequence, err := common.BIP68Sequence(sweepClosure.Seconds)
+		sequence, err := common.BIP68Sequence(sweepClosure.Locktime)
 		if err != nil {
 			return nil, err
 		}
--- a/server/internal/infrastructure/wallet/btc-embedded/wallet.go
+++ b/server/internal/infrastructure/wallet/btc-embedded/wallet.go
@@ -1119,6 +1119,23 @@ func (s *service) VerifyMessageSignature(ctx context.Context, message, signature
 	return sig.Verify(message, s.serverKeyAddr.PubKey()), nil
 }

+func (s *service) GetCurrentBlockTime(ctx context.Context) (*ports.BlockTimestamp, error) {
+	blockhash, blockheight, err := s.wallet.GetBestBlock()
+	if err != nil {
+		return nil, err
+	}
+
+	header, err := s.wallet.GetBlockHeader(blockhash)
+	if err != nil {
+		return nil, err
+	}
+
+	return &ports.BlockTimestamp{
+		Time:   header.Timestamp.Unix(),
+		Height: uint32(blockheight),
+	}, nil
+}
+
 func (s *service) castNotification(tx *wtxmgr.TxRecord) map[string][]ports.VtxoWithValue {
 	vtxos := make(map[string][]ports.VtxoWithValue)

--- a/server/internal/infrastructure/wallet/liquid-standalone/service.go
+++ b/server/internal/infrastructure/wallet/liquid-standalone/service.go
@@ -2,8 +2,12 @@ package oceanwallet

 import (
 	"context"
+	"encoding/json"
 	"errors"
+	"fmt"
 	"io"
+	"net/http"
+	"net/url"
 	"strings"

 	pb "github.com/ark-network/ark/api-spec/protobuf/gen/ocean/v1"
@@ -26,9 +30,18 @@ type service struct {
 	chVtxos       chan map[string][]ports.VtxoWithValue
 	isListening   bool
 	syncedCh      chan struct{}
+	esploraURL    string
 }

-func NewService(addr string) (ports.WalletService, error) {
+type blockInfo struct {
+	Height    int64 `json:"height"`
+	Timestamp int64 `json:"timestamp"`
+}
+
+func NewService(addr string, esploraURL string) (ports.WalletService, error) {
+	if len(esploraURL) == 0 {
+		return nil, fmt.Errorf("missing esplora url")
+	}
 	conn, err := grpc.NewClient(addr, grpc.WithTransportCredentials(insecure.NewCredentials()))
 	if err != nil {
 		return nil, err
@@ -47,6 +60,7 @@ func NewService(addr string) (ports.WalletService, error) {
 		notifyClient:  notifyClient,
 		chVtxos:       chVtxos,
 		syncedCh:      make(chan struct{}),
+		esploraURL:    esploraURL,
 	}

 	ctx := context.Background()
@@ -168,6 +182,45 @@ func (s *service) VerifyMessageSignature(ctx context.Context, message, signature
 	return false, errors.New("not implemented")
 }

+func (s *service) GetCurrentBlockTime(ctx context.Context) (*ports.BlockTimestamp, error) {
+	tipHashURL, err := url.JoinPath(s.esploraURL, "blocks/tip/hash")
+	if err != nil {
+		return nil, err
+	}
+
+	resp, err := http.Get(tipHashURL)
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+
+	hash, err := io.ReadAll(resp.Body)
+	if err != nil {
+		return nil, err
+	}
+
+	blockURL, err := url.JoinPath(s.esploraURL, "block", string(hash))
+	if err != nil {
+		return nil, err
+	}
+
+	resp, err = http.Get(blockURL)
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+
+	var blockInfo blockInfo
+	if err := json.NewDecoder(resp.Body).Decode(&blockInfo); err != nil {
+		return nil, err
+	}
+
+	return &ports.BlockTimestamp{
+		Height: uint32(blockInfo.Height),
+		Time:   blockInfo.Timestamp,
+	}, nil
+}
+
 func (s *service) listenToNotifications() {
 	s.isListening = true
 	defer func() {
--- a/server/test/e2e/covenantless/e2e_test.go
+++ b/server/test/e2e/covenantless/e2e_test.go
@@ -3,22 +3,35 @@ package e2e_test
 import (
 	"bytes"
 	"context"
+	"encoding/hex"
 	"encoding/json"
 	"fmt"
 	"net/http"
 	"os"
+	"strings"
 	"testing"
 	"time"

 	"github.com/ark-network/ark/common"
+	"github.com/ark-network/ark/common/bitcointree"
+	"github.com/ark-network/ark/common/tree"
 	arksdk "github.com/ark-network/ark/pkg/client-sdk"
 	"github.com/ark-network/ark/pkg/client-sdk/client"
 	grpcclient "github.com/ark-network/ark/pkg/client-sdk/client/grpc"
 	"github.com/ark-network/ark/pkg/client-sdk/explorer"
 	"github.com/ark-network/ark/pkg/client-sdk/redemption"
 	"github.com/ark-network/ark/pkg/client-sdk/store"
+	inmemorystoreconfig "github.com/ark-network/ark/pkg/client-sdk/store/inmemory"
 	"github.com/ark-network/ark/pkg/client-sdk/types"
+	singlekeywallet "github.com/ark-network/ark/pkg/client-sdk/wallet/singlekey"
+	inmemorystore "github.com/ark-network/ark/pkg/client-sdk/wallet/singlekey/store/inmemory"
 	utils "github.com/ark-network/ark/server/test/e2e"
+	"github.com/btcsuite/btcd/btcec/v2/schnorr"
+	"github.com/btcsuite/btcd/btcutil/psbt"
+	"github.com/btcsuite/btcd/txscript"
+	"github.com/btcsuite/btcd/wire"
+	"github.com/btcsuite/btcwallet/waddrmgr"
+	"github.com/decred/dcrd/dcrec/secp256k1/v4"
 	"github.com/nbd-wtf/go-nostr"
 	"github.com/nbd-wtf/go-nostr/nip04"
 	"github.com/stretchr/testify/require"
@@ -411,6 +424,163 @@ func TestRedeemNotes(t *testing.T) {
 	require.Error(t, err)
 }

+func TestSendToCLTVMultisigClosure(t *testing.T) {
+	ctx := context.Background()
+	alice, grpcAlice := setupArkSDK(t)
+	defer grpcAlice.Close()
+
+	bobPrivKey, err := secp256k1.GeneratePrivateKey()
+	require.NoError(t, err)
+
+	configStore, err := inmemorystoreconfig.NewConfigStore()
+	require.NoError(t, err)
+
+	walletStore, err := inmemorystore.NewWalletStore()
+	require.NoError(t, err)
+
+	bobWallet, err := singlekeywallet.NewBitcoinWallet(
+		configStore,
+		walletStore,
+	)
+	require.NoError(t, err)
+
+	_, err = bobWallet.Create(ctx, utils.Password, hex.EncodeToString(bobPrivKey.Serialize()))
+	require.NoError(t, err)
+
+	_, err = bobWallet.Unlock(ctx, utils.Password)
+	require.NoError(t, err)
+
+	bobPubKey := bobPrivKey.PubKey()
+
+	// Fund Alice's account
+	offchainAddr, boardingAddress, err := alice.Receive(ctx)
+	require.NoError(t, err)
+
+	aliceAddr, err := common.DecodeAddress(offchainAddr)
+	require.NoError(t, err)
+
+	_, err = utils.RunCommand("nigiri", "faucet", boardingAddress)
+	require.NoError(t, err)
+
+	time.Sleep(5 * time.Second)
+
+	_, err = alice.Settle(ctx)
+	require.NoError(t, err)
+
+	time.Sleep(5 * time.Second)
+
+	const cltvBlocks = 10
+	const sendAmount = 10000
+
+	currentHeight, err := utils.GetBlockHeight(false)
+	require.NoError(t, err)
+
+	vtxoScript := bitcointree.TapscriptsVtxoScript{
+		TapscriptsVtxoScript: tree.TapscriptsVtxoScript{
+			Closures: []tree.Closure{
+				&tree.CLTVMultisigClosure{
+					Locktime: common.Locktime{Type: common.LocktimeTypeBlock, Value: currentHeight + cltvBlocks},
+					MultisigClosure: tree.MultisigClosure{
+						PubKeys: []*secp256k1.PublicKey{bobPubKey},
+					},
+				},
+			},
+		},
+	}
+
+	vtxoTapKey, vtxoTapTree, err := vtxoScript.TapTree()
+	require.NoError(t, err)
+
+	closure := vtxoScript.ForfeitClosures()[0]
+
+	bobAddr := common.Address{
+		HRP:        "tark",
+		VtxoTapKey: vtxoTapKey,
+		Server:     aliceAddr.Server,
+	}
+
+	script, err := closure.Script()
+	require.NoError(t, err)
+
+	merkleProof, err := vtxoTapTree.GetTaprootMerkleProof(txscript.NewBaseTapLeaf(script).TapHash())
+	require.NoError(t, err)
+
+	ctrlBlock, err := txscript.ParseControlBlock(merkleProof.ControlBlock)
+	require.NoError(t, err)
+
+	tapscript := &waddrmgr.Tapscript{
+		ControlBlock:   ctrlBlock,
+		RevealedScript: merkleProof.Script,
+	}
+
+	bobAddrStr, err := bobAddr.Encode()
+	require.NoError(t, err)
+
+	redeemTx, err := alice.SendOffChain(ctx, false, []arksdk.Receiver{arksdk.NewBitcoinReceiver(bobAddrStr, sendAmount)})
+	require.NoError(t, err)
+
+	redeemPtx, err := psbt.NewFromRawBytes(strings.NewReader(redeemTx), true)
+	require.NoError(t, err)
+
+	var bobOutput *wire.TxOut
+	var bobOutputIndex uint32
+	for i, out := range redeemPtx.UnsignedTx.TxOut {
+		if bytes.Equal(out.PkScript[2:], schnorr.SerializePubKey(bobAddr.VtxoTapKey)) {
+			bobOutput = out
+			bobOutputIndex = uint32(i)
+			break
+		}
+	}
+	require.NotNil(t, bobOutput)
+
+	time.Sleep(2 * time.Second)
+
+	alicePkScript, err := common.P2TRScript(aliceAddr.VtxoTapKey)
+	require.NoError(t, err)
+
+	ptx, err := bitcointree.BuildRedeemTx(
+		[]common.VtxoInput{
+			{
+				Outpoint: &wire.OutPoint{
+					Hash:  redeemPtx.UnsignedTx.TxHash(),
+					Index: bobOutputIndex,
+				},
+				Tapscript:   tapscript,
+				WitnessSize: closure.WitnessSize(),
+				Amount:      bobOutput.Value,
+			},
+		},
+		[]*wire.TxOut{
+			{
+				Value:    bobOutput.Value - 500,
+				PkScript: alicePkScript,
+			},
+		},
+	)
+	require.NoError(t, err)
+
+	signedTx, err := bobWallet.SignTransaction(
+		ctx,
+		explorer.NewExplorer("http://localhost:3000", common.BitcoinRegTest),
+		ptx,
+	)
+	require.NoError(t, err)
+
+	// should fail because the tx is not yet valid
+	_, err = grpcAlice.SubmitRedeemTx(ctx, signedTx)
+	require.Error(t, err)
+
+	// Generate blocks to pass the timelock
+	for i := 0; i < cltvBlocks+1; i++ {
+		err = utils.GenerateBlock()
+		require.NoError(t, err)
+		time.Sleep(1 * time.Second)
+	}
+
+	_, err = grpcAlice.SubmitRedeemTx(ctx, signedTx)
+	require.NoError(t, err)
+}
+
 func TestSweep(t *testing.T) {
 	var receive utils.ArkReceive
 	receiveStr, err := runClarkCommand("receive")
--- a/server/test/e2e/test_utils.go
+++ b/server/test/e2e/test_utils.go
@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"io"
 	"os/exec"
+	"strconv"
 	"strings"
 	"sync"
 	"time"
@@ -48,6 +49,24 @@ func GenerateBlock() error {
 	return nil
 }

+func GetBlockHeight(isLiquid bool) (uint32, error) {
+	var out string
+	var err error
+	if isLiquid {
+		out, err = RunCommand("nigiri", "rpc", "--liquid", "getblockcount")
+	} else {
+		out, err = RunCommand("nigiri", "rpc", "getblockcount")
+	}
+	if err != nil {
+		return 0, err
+	}
+	height, err := strconv.ParseUint(strings.TrimSpace(out), 10, 32)
+	if err != nil {
+		return 0, err
+	}
+	return uint32(height), nil
+}
+
 func RunDockerExec(container string, arg ...string) (string, error) {
 	args := append([]string{"exec", "-t", container}, arg...)
 	return RunCommand("docker", args...)