diff --git a/consensus/block.go b/consensus/block.go
index 8bd8687..0015a5c 100644
--- a/consensus/block.go
+++ b/consensus/block.go
@@ -7,7 +7,7 @@ package consensus
 
 import (
 	"fmt"
-	"sort"
+	"slices"
 
 	"forge.lthn.ai/core/go-blockchain/config"
 	"forge.lthn.ai/core/go-blockchain/types"
@@ -50,7 +50,7 @@ func CheckTimestamp(blockTimestamp uint64, flags uint8, adjustedTime uint64, rec
 func medianTimestamp(timestamps []uint64) uint64 {
 	sorted := make([]uint64, len(timestamps))
 	copy(sorted, timestamps)
-	sort.Slice(sorted, func(i, j int) bool { return sorted[i] < sorted[j] })
+	slices.Sort(sorted)
 
 	n := len(sorted)
 	if n == 0 {
diff --git a/wallet/builder.go b/wallet/builder.go
index d66e368..ef05301 100644
--- a/wallet/builder.go
+++ b/wallet/builder.go
@@ -11,9 +11,10 @@ package wallet
 
 import (
 	"bytes"
+	"cmp"
 	"errors"
 	"fmt"
-	"sort"
+	"slices"
 
 	"forge.lthn.ai/core/go-blockchain/config"
 	"forge.lthn.ai/core/go-blockchain/crypto"
@@ -158,8 +159,8 @@ func (b *V1Builder) buildInput(src *Transfer) (types.TxInputToKey, inputMeta, er
 	})
 
 	// Sort by global index (consensus rule).
-	sort.Slice(ring, func(a, b int) bool {
-		return ring[a].GlobalIndex < ring[b].GlobalIndex
+	slices.SortFunc(ring, func(a, b RingMember) int {
+		return cmp.Compare(a.GlobalIndex, b.GlobalIndex)
 	})
 
 	// Find real index after sorting.
diff --git a/wallet/wallet.go b/wallet/wallet.go
index 0c0687a..1df06e9 100644
--- a/wallet/wallet.go
+++ b/wallet/wallet.go
@@ -10,9 +10,10 @@
 package wallet
 
 import (
+	"cmp"
 	"errors"
 	"fmt"
-	"sort"
+	"slices"
 	"strconv"
 
 	"forge.lthn.ai/core/go-blockchain/chain"
@@ -193,8 +194,8 @@ func (w *Wallet) Send(destinations []Destination, fee uint64) (*types.Transactio
 			spendable = append(spendable, tr)
 		}
 	}
-	sort.Slice(spendable, func(i, j int) bool {
-		return spendable[i].Amount > spendable[j].Amount
+	slices.SortFunc(spendable, func(a, b Transfer) int {
+		return cmp.Compare(b.Amount, a.Amount) // descending
 	})
 
 	var selected []Transfer