diff --git a/app/proxyman/mux/mux_test.go b/app/proxyman/mux/mux_test.go
index c6ddc7cfd..f0d495ade 100644
--- a/app/proxyman/mux/mux_test.go
+++ b/app/proxyman/mux/mux_test.go
@@ -43,7 +43,7 @@ func TestReaderWriter(t *testing.T) {
 
 	writePayload := func(writer *Writer, payload ...byte) error {
 		b := buf.New()
-		b.Append(payload)
+		b.Write(payload)
 		return writer.WriteMultiBuffer(buf.NewMultiBufferValue(b))
 	}
 
diff --git a/common/buf/buffer.go b/common/buf/buffer.go
index e7583fccb..4346eb334 100644
--- a/common/buf/buffer.go
+++ b/common/buf/buffer.go
@@ -36,15 +36,8 @@ func (b *Buffer) Clear() {
 }
 
 // AppendBytes appends one or more bytes to the end of the buffer.
-func (b *Buffer) AppendBytes(bytes ...byte) int {
-	return b.Append(bytes)
-}
-
-// Append appends a byte array to the end of the buffer.
-func (b *Buffer) Append(data []byte) int {
-	nBytes := copy(b.v[b.end:], data)
-	b.end += int32(nBytes)
-	return nBytes
+func (b *Buffer) AppendBytes(bytes ...byte) (int, error) {
+	return b.Write(bytes)
 }
 
 // AppendSupplier appends the content of a BytesWriter to the buffer.
diff --git a/common/buf/buffer_test.go b/common/buf/buffer_test.go
index e00ba28f2..d753cbdb4 100644
--- a/common/buf/buffer_test.go
+++ b/common/buf/buffer_test.go
@@ -15,7 +15,7 @@ func TestBufferClear(t *testing.T) {
 	defer buffer.Release()
 
 	payload := "Bytes"
-	buffer.Append([]byte(payload))
+	buffer.Write([]byte(payload))
 	assert(buffer.Len(), Equals, int32(len(payload)))
 
 	buffer.Clear()
diff --git a/common/crypto/auth_test.go b/common/crypto/auth_test.go
index d31826255..f905b150a 100644
--- a/common/crypto/auth_test.go
+++ b/common/crypto/auth_test.go
@@ -29,7 +29,7 @@ func TestAuthenticationReaderWriter(t *testing.T) {
 	rand.Read(rawPayload)
 
 	payload := buf.NewSize(payloadSize)
-	payload.Append(rawPayload)
+	payload.Write(rawPayload)
 	assert(payload.Len(), Equals, int32(payloadSize))
 
 	cache := buf.NewSize(160 * 1024)
@@ -94,11 +94,11 @@ func TestAuthenticationReaderWriterPacket(t *testing.T) {
 
 	var payload buf.MultiBuffer
 	pb1 := buf.New()
-	pb1.Append([]byte("abcd"))
+	pb1.Write([]byte("abcd"))
 	payload.Append(pb1)
 
 	pb2 := buf.New()
-	pb2.Append([]byte("efgh"))
+	pb2.Write([]byte("efgh"))
 	payload.Append(pb2)
 
 	assert(writer.WriteMultiBuffer(payload), IsNil)
diff --git a/proxy/shadowsocks/ota_test.go b/proxy/shadowsocks/ota_test.go
index 106466389..3281e09c0 100644
--- a/proxy/shadowsocks/ota_test.go
+++ b/proxy/shadowsocks/ota_test.go
@@ -29,7 +29,7 @@ func TestNormalChunkWriting(t *testing.T) {
 		[]byte{21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36})))
 
 	b := buf.NewSize(256)
-	b.Append([]byte{11, 12, 13, 14, 15, 16, 17, 18})
+	b.Write([]byte{11, 12, 13, 14, 15, 16, 17, 18})
 	err := writer.WriteMultiBuffer(buf.NewMultiBufferValue(b))
 	assert(err, IsNil)
 	assert(buffer.Bytes(), Equals, []byte{0, 8, 39, 228, 69, 96, 133, 39, 254, 26, 201, 70, 11, 12, 13, 14, 15, 16, 17, 18})
diff --git a/proxy/shadowsocks/protocol.go b/proxy/shadowsocks/protocol.go
index 939cd9cbb..cd1ba64de 100644
--- a/proxy/shadowsocks/protocol.go
+++ b/proxy/shadowsocks/protocol.go
@@ -232,7 +232,7 @@ func EncodeUDPPacket(request *protocol.RequestHeader, payload []byte) (*buf.Buff
 		return nil, newError("failed to write address").Base(err)
 	}
 
-	buffer.Append(payload)
+	buffer.Write(payload)
 
 	if !account.Cipher.IsAEAD() && request.Option.Has(RequestOptionOneTimeAuth) {
 		authenticator := NewAuthenticator(HeaderKeyGenerator(account.Key, iv))
diff --git a/proxy/shadowsocks/protocol_test.go b/proxy/shadowsocks/protocol_test.go
index 65f72a139..2a1fd855c 100644
--- a/proxy/shadowsocks/protocol_test.go
+++ b/proxy/shadowsocks/protocol_test.go
@@ -105,7 +105,7 @@ func TestTCPRequest(t *testing.T) {
 	runTest := func(request *protocol.RequestHeader, payload []byte) {
 		data := buf.New()
 		defer data.Release()
-		data.Append(payload)
+		data.Write(payload)
 
 		cache := buf.New()
 		defer cache.Release()
diff --git a/proxy/socks/protocol.go b/proxy/socks/protocol.go
index bd3a11823..c91d58664 100644
--- a/proxy/socks/protocol.go
+++ b/proxy/socks/protocol.go
@@ -255,7 +255,7 @@ func writeSocks4Response(writer io.Writer, errCode byte, address net.Address, po
 
 	buffer.AppendBytes(0x00, errCode)
 	common.Must(buffer.AppendSupplier(serial.WriteUint16(port.Value())))
-	buffer.Append(address.IP())
+	buffer.Write(address.IP())
 	_, err := writer.Write(buffer.Bytes())
 	return err
 }
@@ -292,7 +292,7 @@ func EncodeUDPPacket(request *protocol.RequestHeader, data []byte) (*buf.Buffer,
 		b.Release()
 		return nil, err
 	}
-	b.Append(data)
+	b.Write(data)
 	return b, nil
 }
 
@@ -358,9 +358,9 @@ func ClientHandshake(request *protocol.RequestHeader, reader io.Reader, writer i
 		account := rawAccount.(*Account)
 
 		b.AppendBytes(0x01, byte(len(account.Username)))
-		b.Append([]byte(account.Username))
+		b.Write([]byte(account.Username))
 		b.AppendBytes(byte(len(account.Password)))
-		b.Append([]byte(account.Password))
+		b.Write([]byte(account.Password))
 	}
 
 	if _, err := writer.Write(b.Bytes()); err != nil {
diff --git a/proxy/socks/protocol_test.go b/proxy/socks/protocol_test.go
index 5857471bc..325f3c7bf 100644
--- a/proxy/socks/protocol_test.go
+++ b/proxy/socks/protocol_test.go
@@ -24,7 +24,7 @@ func TestUDPEncoding(t *testing.T) {
 
 	content := []byte{'a'}
 	payload := buf.New()
-	payload.Append(content)
+	payload.Write(content)
 	assert(writer.WriteMultiBuffer(buf.NewMultiBufferValue(payload)), IsNil)
 
 	reader := NewUDPReader(b)
diff --git a/proxy/vmess/encoding/client.go b/proxy/vmess/encoding/client.go
index b087faecd..407aeed33 100644
--- a/proxy/vmess/encoding/client.go
+++ b/proxy/vmess/encoding/client.go
@@ -70,8 +70,8 @@ func (c *ClientSession) EncodeRequestHeader(header *protocol.RequestHeader, writ
 	defer buffer.Release()
 
 	buffer.AppendBytes(Version)
-	buffer.Append(c.requestBodyIV[:])
-	buffer.Append(c.requestBodyKey[:])
+	buffer.Write(c.requestBodyIV[:])
+	buffer.Write(c.requestBodyKey[:])
 	buffer.AppendBytes(c.responseHeader, byte(header.Option))
 
 	padingLen := dice.Roll(16)
diff --git a/proxy/vmess/encoding/encoding_test.go b/proxy/vmess/encoding/encoding_test.go
index d372189a3..785508c91 100644
--- a/proxy/vmess/encoding/encoding_test.go
+++ b/proxy/vmess/encoding/encoding_test.go
@@ -42,7 +42,7 @@ func TestRequestSerialization(t *testing.T) {
 	common.Must(client.EncodeRequestHeader(expectedRequest, buffer))
 
 	buffer2 := buf.New()
-	buffer2.Append(buffer.Bytes())
+	buffer2.Write(buffer.Bytes())
 
 	sessionHistory := NewSessionHistory()
 	defer common.Close(sessionHistory)
@@ -95,7 +95,7 @@ func TestInvalidRequest(t *testing.T) {
 	common.Must(client.EncodeRequestHeader(expectedRequest, buffer))
 
 	buffer2 := buf.New()
-	buffer2.Append(buffer.Bytes())
+	buffer2.Write(buffer.Bytes())
 
 	sessionHistory := NewSessionHistory()
 	defer common.Close(sessionHistory)
@@ -135,7 +135,7 @@ func TestMuxRequest(t *testing.T) {
 	common.Must(client.EncodeRequestHeader(expectedRequest, buffer))
 
 	buffer2 := buf.New()
-	buffer2.Append(buffer.Bytes())
+	buffer2.Write(buffer.Bytes())
 
 	sessionHistory := NewSessionHistory()
 	defer common.Close(sessionHistory)
diff --git a/transport/internet/headers/srtp/srtp_test.go b/transport/internet/headers/srtp/srtp_test.go
index 8856df80a..9c787013b 100644
--- a/transport/internet/headers/srtp/srtp_test.go
+++ b/transport/internet/headers/srtp/srtp_test.go
@@ -20,7 +20,7 @@ func TestSRTPWrite(t *testing.T) {
 
 	payload := buf.New()
 	payload.AppendSupplier(srtp.Write)
-	payload.Append(content)
+	payload.Write(content)
 
 	assert(payload.Len(), Equals, int32(len(content))+srtp.Size())
 }
diff --git a/transport/internet/headers/utp/utp_test.go b/transport/internet/headers/utp/utp_test.go
index 845f8b1fb..0eb65dc53 100644
--- a/transport/internet/headers/utp/utp_test.go
+++ b/transport/internet/headers/utp/utp_test.go
@@ -20,7 +20,7 @@ func TestUTPWrite(t *testing.T) {
 
 	payload := buf.New()
 	payload.AppendSupplier(utp.Write)
-	payload.Append(content)
+	payload.Write(content)
 
 	assert(payload.Len(), Equals, int32(len(content))+utp.Size())
 }
diff --git a/transport/internet/kcp/io.go b/transport/internet/kcp/io.go
index a8e5f67b3..8fcd879ff 100644
--- a/transport/internet/kcp/io.go
+++ b/transport/internet/kcp/io.go
@@ -85,7 +85,7 @@ func (w *KCPPacketWriter) Write(b []byte) (int, error) {
 			return len(eb), nil
 		}))
 	} else {
-		bb.Append(b)
+		bb.Write(b)
 	}
 
 	_, err := w.Writer.Write(bb.Bytes())
diff --git a/transport/internet/kcp/segment.go b/transport/internet/kcp/segment.go
index b5d10de4a..e4e9e8530 100755
--- a/transport/internet/kcp/segment.go
+++ b/transport/internet/kcp/segment.go
@@ -76,7 +76,7 @@ func (s *DataSegment) parse(conv uint16, cmd Command, opt SegmentOption, buf []b
 		return false, nil
 	}
 	s.Data().Clear()
-	s.Data().Append(buf[:dataLen])
+	s.Data().Write(buf[:dataLen])
 	buf = buf[dataLen:]
 
 	return true, buf
diff --git a/transport/internet/kcp/segment_test.go b/transport/internet/kcp/segment_test.go
index 2f1ba70a8..7dfe60552 100644
--- a/transport/internet/kcp/segment_test.go
+++ b/transport/internet/kcp/segment_test.go
@@ -24,7 +24,7 @@ func TestDataSegment(t *testing.T) {
 		Number:      4,
 		SendingNext: 5,
 	}
-	seg.Data().Append([]byte{'a', 'b', 'c', 'd'})
+	seg.Data().Write([]byte{'a', 'b', 'c', 'd'})
 
 	nBytes := seg.ByteSize()
 	bytes := make([]byte, nBytes)
diff --git a/transport/pipe/pipe_test.go b/transport/pipe/pipe_test.go
index 14fa2de91..beace25f9 100644
--- a/transport/pipe/pipe_test.go
+++ b/transport/pipe/pipe_test.go
@@ -15,7 +15,7 @@ func TestPipeReadWrite(t *testing.T) {
 	pReader, pWriter := New()
 	payload := []byte{'a', 'b', 'c', 'd'}
 	b := buf.New()
-	b.Append(payload)
+	b.Write(payload)
 	assert(pWriter.WriteMultiBuffer(buf.NewMultiBufferValue(b)), IsNil)
 
 	rb, err := pReader.ReadMultiBuffer()
@@ -29,7 +29,7 @@ func TestPipeCloseError(t *testing.T) {
 	pReader, pWriter := New()
 	payload := []byte{'a', 'b', 'c', 'd'}
 	b := buf.New()
-	b.Append(payload)
+	b.Write(payload)
 	assert(pWriter.WriteMultiBuffer(buf.NewMultiBufferValue(b)), IsNil)
 	pWriter.CloseError()
 
@@ -44,7 +44,7 @@ func TestPipeClose(t *testing.T) {
 	pReader, pWriter := New()
 	payload := []byte{'a', 'b', 'c', 'd'}
 	b := buf.New()
-	b.Append(payload)
+	b.Write(payload)
 	assert(pWriter.WriteMultiBuffer(buf.NewMultiBufferValue(b)), IsNil)
 	assert(pWriter.Close(), IsNil)