diff --git a/nbt/interface.go b/nbt/interface.go
new file mode 100644
index 0000000..1821013
--- /dev/null
+++ b/nbt/interface.go
@@ -0,0 +1,9 @@
+package nbt
+
+type Unmarshaler interface {
+	Unmarshal(tagType byte, tagName string, r DecoderReader) error
+}
+
+//type Marshaler interface{
+//	Marshal()
+//}
diff --git a/nbt/interface_test.go b/nbt/interface_test.go
new file mode 100644
index 0000000..41ad9a7
--- /dev/null
+++ b/nbt/interface_test.go
@@ -0,0 +1 @@
+package nbt
diff --git a/nbt/marshal_test.go b/nbt/marshal_test.go
deleted file mode 100644
index 0bc0bd8..0000000
--- a/nbt/marshal_test.go
+++ /dev/null
@@ -1,35 +0,0 @@
-package nbt
-
-import (
-	"bytes"
-	"reflect"
-	"testing"
-)
-
-func TestMarshal(t *testing.T) {
-	var (
-		want = []byte{
-			0x0A, 0, 0,
-			0x08, 0, 4, 0x4e, 0x61, 0x6d, 0x65, 0, 4, 0x54, 0x6e, 0x7a, 0x65,
-			0x01, 0x00, 0x08, 0x42, 0x79, 0x74, 0x65, 0x54, 0x65, 0x73, 0x74, 0xFF,
-
-			0,
-		}
-		value struct {
-			Name     string
-			ByteTest byte
-		}
-	)
-	value.Name = "Tnze"
-	value.ByteTest = 0xFF
-
-	var buf bytes.Buffer
-	if err := Marshal(&buf, value); err != nil {
-		t.Fatal(err)
-	}
-
-	gets := buf.Bytes()
-	if !reflect.DeepEqual(gets, want) {
-		t.Errorf("marshal wrong: get [% 02x], want [% 02x]", gets, want)
-	}
-}
diff --git a/nbt/nbt.go b/nbt/nbt.go
index 9c14996..794708e 100644
--- a/nbt/nbt.go
+++ b/nbt/nbt.go
@@ -24,19 +24,17 @@ const (
 	TagLongArray
 )
 
+type DecoderReader = interface {
+	io.ByteScanner
+	io.Reader
+}
 type Decoder struct {
-	r interface {
-		io.ByteScanner
-		io.Reader
-	}
+	r DecoderReader
 }
 
 func NewDecoder(r io.Reader) *Decoder {
 	d := new(Decoder)
-	if br, ok := r.(interface {
-		io.ByteScanner
-		io.Reader
-	}); ok {
+	if br, ok := r.(DecoderReader); ok {
 		d.r = br
 	} else {
 		d.r = bufio.NewReader(r)
diff --git a/nbt/nbt_test.go b/nbt/nbt_test.go
index debe38d..4132892 100644
--- a/nbt/nbt_test.go
+++ b/nbt/nbt_test.go
@@ -53,7 +53,7 @@ func TestUnmarshal_simple(t *testing.T) {
 		t.Errorf("Unmarshal NBT fail: get %q, want %q", value.Name, "Bananrama")
 	}
 
-	//test skip
+	//test rawRead
 	var empty struct{}
 	if err := Unmarshal(data, &empty); err != nil {
 		t.Fatal(err)
@@ -189,7 +189,7 @@ func TestUnmarshal_bitTest(t *testing.T) {
 		t.Errorf("parse fail, expect %v, get %v", want, value)
 	}
 
-	//test skip
+	//test rawRead
 	var empty struct{}
 	r, err = gzip.NewReader(bytes.NewReader(data))
 	if err != nil {
diff --git a/nbt/read.go b/nbt/read.go
index a699605..9767168 100644
--- a/nbt/read.go
+++ b/nbt/read.go
@@ -63,6 +63,12 @@ func (d *Decoder) checkCompressed() (compress string, err error) {
 var ErrEND = errors.New("unexpected TAG_End")
 
 func (d *Decoder) unmarshal(val reflect.Value, tagType byte, tagName string) error {
+	if val.CanInterface() {
+		if i, ok := val.Interface().(Unmarshaler); ok {
+			return i.Unmarshal(tagType, tagName, d.r)
+		}
+	}
+
 	switch tagType {
 	default:
 		return fmt.Errorf("unknown Tag 0x%02x", tagType)
@@ -311,7 +317,7 @@ func (d *Decoder) unmarshal(val reflect.Value, tagType byte, tagName string) err
 						return err
 					}
 				} else {
-					if err := d.skip(tt); err != nil {
+					if err := d.rawRead(tt); err != nil {
 						return err
 					}
 				}
@@ -344,10 +350,10 @@ func (d *Decoder) unmarshal(val reflect.Value, tagType byte, tagName string) err
 	return nil
 }
 
-func (d *Decoder) skip(tagType byte) error {
+func (d *Decoder) rawRead(tagType byte) error {
 	switch tagType {
 	default:
-		return fmt.Errorf("unknown to skip 0x%02x", tagType)
+		return fmt.Errorf("unknown to read 0x%02x", tagType)
 	case TagByte:
 		_, err := d.r.ReadByte()
 		return err
@@ -403,7 +409,7 @@ func (d *Decoder) skip(tagType byte) error {
 			return err
 		}
 		for i := 0; i < int(listLen); i++ {
-			if err := d.skip(listType); err != nil {
+			if err := d.rawRead(listType); err != nil {
 				return err
 			}
 		}
@@ -416,7 +422,7 @@ func (d *Decoder) skip(tagType byte) error {
 			if tt == TagEnd {
 				break
 			}
-			err = d.skip(tt)
+			err = d.rawRead(tt)
 			if err != nil {
 				return err
 			}