diff --git a/rand_1.21.go b/rand_1.21.go
new file mode 100644
index 0000000..dc678e5
--- /dev/null
+++ b/rand_1.21.go
@@ -0,0 +1,19 @@
+//go:build !go1.22
+
+package tea
+
+import (
+	_ "unsafe" // required by go:linkname
+)
+
+// randuint32 returns a lock free uint32 value.
+//
+// Too much legacy code has go:linkname references
+// to runtime.fastrand and friends, so keep these around for now.
+// Code should migrate to math/rand/v2.Uint64,
+// which is just as fast, but that's only available in Go 1.22+.
+// It would be reasonable to remove these in Go 1.24.
+// Do not call these from package runtime.
+//
+//go:linkname randuint32 runtime.fastrand
+func randuint32() uint32
diff --git a/rand_1.22.go b/rand_1.22.go
new file mode 100644
index 0000000..f2a802d
--- /dev/null
+++ b/rand_1.22.go
@@ -0,0 +1,11 @@
+//go:build go1.22
+
+package tea
+
+import (
+	"math/rand/v2"
+)
+
+func randuint32() uint32 {
+	return rand.Uint32()
+}
diff --git a/tea.go b/tea.go
index 08d8141..2754482 100644
--- a/tea.go
+++ b/tea.go
@@ -4,15 +4,10 @@ package tea
 
 import (
 	"encoding/binary"
-	_ "unsafe" // required by go:linkname
 )
 
 type TEA [4]uint32
 
-// randuint32 returns a lock free uint32 value.
-//go:linkname randuint32 runtime.fastrand
-func randuint32() uint32
-
 //go:nosplit
 func NewTeaCipher(key []byte) (t TEA) {
 	if len(key) == 16 {
diff --git a/tea_test.go b/tea_test.go
index f3e8809..4ec66f8 100644
--- a/tea_test.go
+++ b/tea_test.go
@@ -1,6 +1,3 @@
-//go:build ignore
-// +build ignore
-
 package tea
 
 import (
@@ -8,8 +5,6 @@ import (
 	"crypto/rand"
 	"encoding/hex"
 	"testing"
-
-	"github.com/Mrs4s/MiraiGo/utils"
 )
 
 var testTEA = NewTeaCipher([]byte("0123456789ABCDEF"))
@@ -32,7 +27,7 @@ var sampleData = func() [][3]string {
 	}
 	for i := range out {
 		c, _ := hex.DecodeString(out[i][ENC])
-		out[i][ENC] = utils.B2S(c)
+		out[i][ENC] = string(c)
 	}
 	return out
 }()
@@ -40,13 +35,13 @@ var sampleData = func() [][3]string {
 func TestTEA(t *testing.T) {
 	// Self Testing
 	for _, sample := range sampleData {
-		tea := NewTeaCipher(utils.S2B(sample[KEY]))
-		dat := utils.B2S(tea.Decrypt(utils.S2B(sample[ENC])))
+		tea := NewTeaCipher([]byte(sample[KEY]))
+		dat := string(tea.Decrypt([]byte(sample[ENC])))
 		if dat != sample[DAT] {
 			t.Fatalf("error decrypt %v %x", sample, dat)
 		}
-		enc := utils.B2S(tea.Encrypt(utils.S2B(sample[DAT])))
-		dat = utils.B2S(tea.Decrypt(utils.S2B(enc)))
+		enc := string(tea.Encrypt([]byte(sample[DAT])))
+		dat = string(tea.Decrypt([]byte(enc)))
 		if dat != sample[DAT] {
 			t.Fatal("error self test", sample)
 		}