diff --git a/go.mod b/go.mod
index 19475c9..e9bda9f 100644
--- a/go.mod
+++ b/go.mod
@@ -6,7 +6,7 @@ toolchain go1.23.2
 
 require (
 	go.etcd.io/bbolt v1.3.11
-	go.sia.tech/core v0.8.0
+	go.sia.tech/core v0.8.1-0.20241217152409-7950a7ca324b
 	go.sia.tech/mux v1.3.0
 	go.uber.org/zap v1.27.0
 	golang.org/x/crypto v0.31.0
diff --git a/go.sum b/go.sum
index 25118a3..bf2c74b 100644
--- a/go.sum
+++ b/go.sum
@@ -6,8 +6,8 @@ github.com/stretchr/testify v1.8.1 h1:w7B6lhMri9wdJUVmEZPGGhZzrYTPvgJArz7wNPgYKs
 github.com/stretchr/testify v1.8.1/go.mod h1:w2LPCIKwWwSfY2zedu0+kehJoqGctiVI29o6fzry7u4=
 go.etcd.io/bbolt v1.3.11 h1:yGEzV1wPz2yVCLsD8ZAiGHhHVlczyC9d1rP43/VCRJ0=
 go.etcd.io/bbolt v1.3.11/go.mod h1:dksAq7YMXoljX0xu6VF5DMZGbhYYoLUalEiSySYAS4I=
-go.sia.tech/core v0.8.0 h1:J6vZQlVhpj4bTVeuC2GKkfkGEs8jf0j651Kl1wwOxjg=
-go.sia.tech/core v0.8.0/go.mod h1:Wj1qzvpMM2rqEQjwWJEbCBbe9VWX/mSJUu2Y2ABl1QA=
+go.sia.tech/core v0.8.1-0.20241217152409-7950a7ca324b h1:VRkb6OOX1KawLQwuqOEHLcjha8gxVX0tAyu2Dyoq8Ek=
+go.sia.tech/core v0.8.1-0.20241217152409-7950a7ca324b/go.mod h1:Wj1qzvpMM2rqEQjwWJEbCBbe9VWX/mSJUu2Y2ABl1QA=
 go.sia.tech/mux v1.3.0 h1:hgR34IEkqvfBKUJkAzGi31OADeW2y7D6Bmy/Jcbop9c=
 go.sia.tech/mux v1.3.0/go.mod h1:I46++RD4beqA3cW9Xm9SwXbezwPqLvHhVs9HLpDtt58=
 go.uber.org/goleak v1.3.0 h1:2K3zAYmnTNqV73imy9J1T3WC+gmCePx2hEGkimedGto=
diff --git a/rhp/v4/rpc_test.go b/rhp/v4/rpc_test.go
index 38a52d5..3911dd1 100644
--- a/rhp/v4/rpc_test.go
+++ b/rhp/v4/rpc_test.go
@@ -392,11 +392,7 @@ func TestRPCRefresh(t *testing.T) {
 		revision.Revision = fundResult.Revision
 
 		// upload data
-		at := proto4.AccountToken{
-			Account:    account,
-			ValidUntil: time.Now().Add(5 * time.Minute),
-		}
-		at.Signature = renterKey.SignHash(at.SigHash())
+		at := account.Token(renterKey, hostKey.PublicKey())
 		wRes, err := rhp4.RPCWriteSector(context.Background(), transport, settings.Prices, at, bytes.NewReader(bytes.Repeat([]byte{1}, proto4.LeafSize)), proto4.LeafSize)
 		if err != nil {
 			t.Fatal(err)
@@ -550,11 +546,7 @@ func TestRPCRenew(t *testing.T) {
 		revision.Revision = fundResult.Revision
 
 		// upload data
-		at := proto4.AccountToken{
-			Account:    account,
-			ValidUntil: time.Now().Add(5 * time.Minute),
-		}
-		at.Signature = renterKey.SignHash(at.SigHash())
+		at := account.Token(renterKey, hostKey.PublicKey())
 		wRes, err := rhp4.RPCWriteSector(context.Background(), transport, settings.Prices, at, bytes.NewReader(bytes.Repeat([]byte{1}, proto4.LeafSize)), proto4.LeafSize)
 		if err != nil {
 			t.Fatal(err)
@@ -753,13 +745,7 @@ func TestAccounts(t *testing.T) {
 	cs := cm.TipState()
 
 	// test operations against unknown account
-	token := proto4.AccountToken{
-		Account:    account,
-		ValidUntil: time.Now().Add(time.Hour),
-	}
-
-	tokenSigHash := token.SigHash()
-	token.Signature = renterKey.SignHash(tokenSigHash)
+	token := account.Token(renterKey, hostKey.PublicKey())
 	_, err = rhp4.RPCVerifySector(context.Background(), transport, settings.Prices, token, types.Hash256{1})
 	if err == nil || !strings.Contains(err.Error(), proto4.ErrNotEnoughFunds.Error()) {
 		t.Fatal(err)
@@ -886,14 +872,7 @@ func TestReadWriteSector(t *testing.T) {
 		t.Fatal(err)
 	}
 	revision.Revision = fundResult.Revision
-
-	token := proto4.AccountToken{
-		Account:    account,
-		ValidUntil: time.Now().Add(time.Hour),
-	}
-	tokenSigHash := token.SigHash()
-	token.Signature = renterKey.SignHash(tokenSigHash)
-
+	token := account.Token(renterKey, hostKey.PublicKey())
 	data := frand.Bytes(1024)
 
 	// store the sector
@@ -1005,12 +984,7 @@ func TestAppendSectors(t *testing.T) {
 	revision.Revision = fundResult.Revision
 	assertLastRevision(t)
 
-	token := proto4.AccountToken{
-		Account:    account,
-		ValidUntil: time.Now().Add(time.Hour),
-	}
-	tokenSigHash := token.SigHash()
-	token.Signature = renterKey.SignHash(tokenSigHash)
+	token := account.Token(renterKey, hostKey.PublicKey())
 
 	// store random sectors
 	roots := make([]types.Hash256, 0, 10)
@@ -1121,14 +1095,7 @@ func TestVerifySector(t *testing.T) {
 		t.Fatal(err)
 	}
 	revision.Revision = fundResult.Revision
-
-	token := proto4.AccountToken{
-		Account:    account,
-		ValidUntil: time.Now().Add(time.Hour),
-	}
-	tokenSigHash := token.SigHash()
-	token.Signature = renterKey.SignHash(tokenSigHash)
-
+	token := account.Token(renterKey, hostKey.PublicKey())
 	data := frand.Bytes(1024)
 
 	// store the sector
@@ -1212,13 +1179,7 @@ func TestRPCFreeSectors(t *testing.T) {
 		t.Fatal(err)
 	}
 	revision.Revision = fundResult.Revision
-
-	token := proto4.AccountToken{
-		Account:    account,
-		ValidUntil: time.Now().Add(time.Hour),
-	}
-	tokenSigHash := token.SigHash()
-	token.Signature = renterKey.SignHash(tokenSigHash)
+	token := account.Token(renterKey, hostKey.PublicKey())
 
 	roots := make([]types.Hash256, 10)
 	for i := range roots {
@@ -1333,13 +1294,7 @@ func TestRPCSectorRoots(t *testing.T) {
 		t.Fatal(err)
 	}
 	revision.Revision = fundResult.Revision
-
-	token := proto4.AccountToken{
-		Account:    account,
-		ValidUntil: time.Now().Add(time.Hour),
-	}
-	tokenSigHash := token.SigHash()
-	token.Signature = renterKey.SignHash(tokenSigHash)
+	token := account.Token(renterKey, hostKey.PublicKey())
 
 	roots := make([]types.Hash256, 0, 50)
 
@@ -1441,12 +1396,7 @@ func BenchmarkWrite(b *testing.B) {
 		b.Fatal(err)
 	}
 	revision.Revision = fundResult.Revision
-
-	token := proto4.AccountToken{
-		Account:    account,
-		ValidUntil: time.Now().Add(time.Hour),
-	}
-	token.Signature = renterKey.SignHash(token.SigHash())
+	token := account.Token(renterKey, hostKey.PublicKey())
 
 	var sectors [][proto4.SectorSize]byte
 	for i := 0; i < b.N; i++ {
@@ -1529,12 +1479,7 @@ func BenchmarkRead(b *testing.B) {
 		b.Fatal(err)
 	}
 	revision.Revision = fundResult.Revision
-
-	token := proto4.AccountToken{
-		Account:    account,
-		ValidUntil: time.Now().Add(time.Hour),
-	}
-	token.Signature = renterKey.SignHash(token.SigHash())
+	token := account.Token(renterKey, hostKey.PublicKey())
 
 	var sectors [][proto4.SectorSize]byte
 	roots := make([]types.Hash256, 0, b.N)
@@ -1629,12 +1574,7 @@ func BenchmarkContractUpload(b *testing.B) {
 		b.Fatal(err)
 	}
 	revision.Revision = fundResult.Revision
-
-	token := proto4.AccountToken{
-		Account:    account,
-		ValidUntil: time.Now().Add(time.Hour),
-	}
-	token.Signature = renterKey.SignHash(token.SigHash())
+	token := account.Token(renterKey, hostKey.PublicKey())
 
 	var sectors [][proto4.SectorSize]byte
 	roots := make([]types.Hash256, 0, b.N)