diff --git a/example/simple-chat/chat.go b/example/simple-chat/chat.go
index 12ec715..bf1a639 100644
--- a/example/simple-chat/chat.go
+++ b/example/simple-chat/chat.go
@@ -21,7 +21,7 @@ const (
 	ProtoQuitRoom
 	ProtoSendMessage
 
-	ProtoRecvMessage = iota + 1000
+	ProtoRecvMessage = iota - ProtoSendMessage + 1000
 )
 
 type Proto struct {
@@ -123,9 +123,15 @@ func (s *service) sendMessage(req *proto.Request[Proto]) {
 
 func main() {
 
-	engine := proto.New[Proto, ProtoType](func() proto.Proto[Proto, ProtoType] {
+	instancePool := proto.NewInstancePool[Proto, ProtoType](func() proto.Proto[Proto, ProtoType] {
 		return new(Proto)
 	})
+
+	engine := proto.New[Proto, ProtoType](instancePool.Alloc)
+	engine.RegisterDestroyProto(func(_ *qWebsocket.HandlerParams, proto proto.Proto[Proto, ProtoType]) {
+		instancePool.Free(proto)
+	})
+
 	s := &service{}
 
 	engine.Register(ProtoJoinRoom, s.joinRoom)
diff --git a/proto/codec_xml.go b/proto/codec_xml.go
new file mode 100644
index 0000000..95506a4
--- /dev/null
+++ b/proto/codec_xml.go
@@ -0,0 +1,16 @@
+package proto
+
+import (
+	"encoding/xml"
+	"io"
+)
+
+type CodecXML[T any, K comparable] struct{}
+
+func (k CodecXML[T, K]) Marshal(w io.Writer, val Proto[T, K]) error {
+	return xml.NewEncoder(w).Encode(val.Value())
+}
+
+func (k CodecXML[T, K]) Unmarshal(r io.Reader, ptr Proto[T, K]) error {
+	return xml.NewDecoder(r).Decode(ptr.Self())
+}
diff --git a/proto/engine.go b/proto/engine.go
index cb9fb84..6335f10 100644
--- a/proto/engine.go
+++ b/proto/engine.go
@@ -6,12 +6,17 @@ import (
 	"log"
 )
 
-type HandlerFunc[T any] func(*Request[T])
+type (
+	HandlerFunc[T any]                    func(*Request[T])
+	NewProtoFunc[T any, K comparable]     func() Proto[T, K]
+	DestroyProtoFunc[T any, K comparable] func(params *qWebsocket.HandlerParams, proto Proto[T, K])
+)
 
 type Engine[T any, K comparable] struct {
-	codec    Codec[T, K]
-	handlers map[K]HandlerFunc[T]
-	newProto func() Proto[T, K]
+	codec        Codec[T, K]
+	handlers     map[K]HandlerFunc[T]
+	newProto     NewProtoFunc[T, K]
+	destroyProto DestroyProtoFunc[T, K]
 }
 
 // Handler
@@ -20,6 +25,10 @@ type Engine[T any, K comparable] struct {
 func (e *Engine[T, K]) Handler(params *qWebsocket.HandlerParams) {
 	proto := e.newProto()
 
+	if e.destroyProto != nil {
+		defer e.destroyProto(params, proto)
+	}
+
 	if err := e.codec.Unmarshal(bytes.NewReader(params.Request), proto); err != nil {
 		log.Println("Proto engine codec error:", err)
 		return
@@ -46,3 +55,7 @@ func (e *Engine[T, K]) Register(key K, handler HandlerFunc[T]) {
 func (e *Engine[T, K]) RegisterCodec(codec Codec[T, K]) {
 	e.codec = codec
 }
+
+func (e *Engine[T, K]) RegisterDestroyProto(handler DestroyProtoFunc[T, K]) {
+	e.destroyProto = handler
+}
diff --git a/proto/instance.go b/proto/instance.go
new file mode 100644
index 0000000..0cfd674
--- /dev/null
+++ b/proto/instance.go
@@ -0,0 +1,27 @@
+package proto
+
+import "sync"
+
+type InstancePool[T any, K comparable] struct {
+	pool sync.Pool
+}
+
+func (k *InstancePool[T, K]) Alloc() Proto[T, K] {
+	return k.pool.Get().(Proto[T, K])
+}
+
+func (k *InstancePool[T, K]) Free(proto Proto[T, K]) {
+	// if Proto impl Resetter interface
+	if free, ok := proto.(Resetter); ok {
+		free.Reset()
+	}
+	k.pool.Put(proto)
+}
+
+func NewInstancePool[T any, K comparable](newProto func() Proto[T, K]) *InstancePool[T, K] {
+	return &InstancePool[T, K]{
+		pool: sync.Pool{
+			New: func() any { return newProto() },
+		},
+	}
+}
diff --git a/proto/proto.go b/proto/proto.go
index d850e56..6f88ece 100644
--- a/proto/proto.go
+++ b/proto/proto.go
@@ -1,12 +1,38 @@
 package proto
 
 type Proto[T any, K comparable] interface {
+	// Key realizes the value that returns Proto can be comparable
+	//
+	// case:
+	// type Proto struct {
+	//		Type 	uint32
+	//		Message string
+	// }
+	//
+	// func (p *Proto) Key() uint32 { return p.Type }
 	Key() K
+	// Value return a copy of itself
+	//
+	// case:
+	// func (p *Proto) Value() Proto { return *p }
 	Value() T
+	// Self return a pointer of itself
+	//
+	// case:
+	// func (p *Proto) Self() *Proto { return p }
 	Self() *T
 }
 
-func New[T any, K comparable](newProto func() Proto[T, K]) *Engine[T, K] {
+type Resetter interface {
+	Reset()
+}
+
+// New a proto engine instance
+//
+// args
+//
+// - newProto should be return a Proto instance
+func New[T any, K comparable](newProto NewProtoFunc[T, K]) *Engine[T, K] {
 	return &Engine[T, K]{
 		codec:    &CodecJSON[T, K]{},
 		handlers: make(map[K]HandlerFunc[T]),