diff --git a/cpp/src/msgpack/unpack.h b/cpp/src/msgpack/unpack.h
index e17d0d85..1f43ab75 100644
--- a/cpp/src/msgpack/unpack.h
+++ b/cpp/src/msgpack/unpack.h
@@ -20,6 +20,15 @@
 
 #include "msgpack/zone.h"
 #include "msgpack/object.h"
+#include <string.h>
+
+#ifndef MSGPACK_UNPACKER_INIT_BUFFER_SIZE
+#define MSGPACK_UNPACKER_INIT_BUFFER_SIZE (64*1024)
+#endif
+
+#ifndef MSGPACK_UNPACKER_RESERVE_SIZE
+#define MSGPACK_UNPACKER_RESERVE_SIZE (32*1024)
+#endif
 
 #ifdef __cplusplus
 extern "C" {
@@ -37,6 +46,10 @@ typedef struct msgpack_unpacker {
 	void* ctx;
 } msgpack_unpacker;
 
+typedef struct msgpack_unpacked {
+	msgpack_zone* zone;
+	msgpack_object data;
+} msgpack_unpacked;
 
 bool msgpack_unpacker_init(msgpack_unpacker* mpac, size_t initial_buffer_size);
 void msgpack_unpacker_destroy(msgpack_unpacker* mpac);
@@ -49,6 +62,13 @@ static inline char*  msgpack_unpacker_buffer(msgpack_unpacker* mpac);
 static inline size_t msgpack_unpacker_buffer_capacity(const msgpack_unpacker* mpac);
 static inline void   msgpack_unpacker_buffer_consumed(msgpack_unpacker* mpac, size_t size);
 
+bool msgpack_unpacker_next(msgpack_unpacker* mpac, msgpack_unpacked* pac);
+
+static inline void msgpack_unpacked_init(msgpack_unpacked* result);
+static inline void msgpack_unpacked_destroy(msgpack_unpacked* result);
+
+static inline msgpack_zone* msgpack_unpacked_release_zone(msgpack_unpacked* result);
+
 
 int msgpack_unpacker_execute(msgpack_unpacker* mpac);
 
@@ -63,6 +83,9 @@ void msgpack_unpacker_reset(msgpack_unpacker* mpac);
 static inline size_t msgpack_unpacker_message_size(const msgpack_unpacker* mpac);
 
 
+bool msgpack_unpack_next(msgpack_unpacked* result,
+		const char* data, size_t len, size_t* off);
+
 
 typedef enum {
 	MSGPACK_UNPACK_SUCCESS				=  2,
@@ -73,7 +96,7 @@ typedef enum {
 
 msgpack_unpack_return
 msgpack_unpack(const char* data, size_t len, size_t* off,
-		msgpack_zone* z, msgpack_object* result);
+		msgpack_zone* result_zone, msgpack_object* result);
 
 
 static inline size_t msgpack_unpacker_parsed_size(const msgpack_unpacker* mpac);
@@ -115,6 +138,31 @@ size_t msgpack_unpacker_parsed_size(const msgpack_unpacker* mpac)
 }
 
 
+void msgpack_unpacked_init(msgpack_unpacked* result)
+{
+	memset(result, 0, sizeof(msgpack_unpacked));
+}
+
+void msgpack_unpacked_destroy(msgpack_unpacked* result)
+{
+	if(result->zone != NULL) {
+		msgpack_zone_free(result->zone);
+		result->zone = NULL;
+		memset(&result->data, 0, sizeof(msgpack_object));
+	}
+}
+
+msgpack_zone* msgpack_unpacked_release_zone(msgpack_unpacked* result)
+{
+	if(result->zone != NULL) {
+		msgpack_zone* z = result->zone;
+		result->zone = NULL;
+		return z;
+	}
+	return NULL;
+}
+
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/cpp/src/msgpack/unpack.hpp b/cpp/src/msgpack/unpack.hpp
index e1617efb..7b45017a 100644
--- a/cpp/src/msgpack/unpack.hpp
+++ b/cpp/src/msgpack/unpack.hpp
@@ -24,8 +24,9 @@
 #include <memory>
 #include <stdexcept>
 
+// backward compatibility
 #ifndef MSGPACK_UNPACKER_DEFAULT_INITIAL_BUFFER_SIZE
-#define MSGPACK_UNPACKER_DEFAULT_INITIAL_BUFFER_SIZE (32*1024)
+#define MSGPACK_UNPACKER_DEFAULT_INITIAL_BUFFER_SIZE MSGPACK_UNPACKER_INIT_BUFFER_SIZE
 #endif
 
 namespace msgpack {
@@ -64,12 +65,12 @@ private:
 
 class unpacker : public msgpack_unpacker {
 public:
-	unpacker(size_t init_buffer_size = MSGPACK_UNPACKER_DEFAULT_INITIAL_BUFFER_SIZE);
+	unpacker(size_t init_buffer_size = MSGPACK_UNPACKER_INIT_BUFFER_SIZE);
 	~unpacker();
 
 public:
 	/*! 1. reserve buffer. at least `size' bytes of capacity will be ready */
-	void reserve_buffer(size_t size);
+	void reserve_buffer(size_t size = MSGPACK_UNPACKER_RESERVE_SIZE);
 
 	/*! 2. read data to the buffer() up to buffer_capacity() bytes */
 	char* buffer();
diff --git a/cpp/src/unpack.c b/cpp/src/unpack.c
index 4a425264..0c21780b 100644
--- a/cpp/src/unpack.c
+++ b/cpp/src/unpack.c
@@ -363,20 +363,46 @@ void msgpack_unpacker_reset(msgpack_unpacker* mpac)
 	mpac->parsed = 0;
 }
 
+bool msgpack_unpacker_next(msgpack_unpacker* mpac, msgpack_unpacked* result)
+{
+	if(result->zone != NULL) {
+		msgpack_zone_free(result->zone);
+	}
+
+	int ret = msgpack_unpacker_execute(mpac);
+
+	if(ret <= 0) {
+		result->zone = NULL;
+		memset(&result->data, 0, sizeof(msgpack_object));
+		return false;
+	}
+
+	result->zone = msgpack_unpacker_release_zone(mpac);
+	result->data = msgpack_unpacker_data(mpac);
+	msgpack_unpacker_reset(mpac);
+
+	return true;
+}
+
 
 msgpack_unpack_return
 msgpack_unpack(const char* data, size_t len, size_t* off,
-		msgpack_zone* z, msgpack_object* result)
+		msgpack_zone* result_zone, msgpack_object* result)
 {
+	size_t noff = 0;
+	if(off != NULL) { noff = *off; }
+
+	if(len <= noff) {
+		// FIXME
+		return MSGPACK_UNPACK_CONTINUE;
+	}
+
 	template_context ctx;
 	template_init(&ctx);
 
-	ctx.user.z = z;
+	ctx.user.z = result_zone;
 	ctx.user.referenced = false;
 
-	size_t noff = 0;
-	if(off != NULL) { noff = *off; }
-
 	int e = template_execute(&ctx, data, len, &noff);
 	if(e < 0) {
 		return MSGPACK_UNPACK_PARSE_ERROR;
@@ -397,3 +423,37 @@ msgpack_unpack(const char* data, size_t len, size_t* off,
 	return MSGPACK_UNPACK_SUCCESS;
 }
 
+bool msgpack_unpack_next(msgpack_unpacked* result,
+		const char* data, size_t len, size_t* off)
+{
+	msgpack_unpacked_destroy(result);
+
+	size_t noff = 0;
+	if(off != NULL) { noff = *off; }
+
+	if(len <= noff) {
+		return false;
+	}
+
+	msgpack_zone* z = msgpack_zone_new(MSGPACK_ZONE_CHUNK_SIZE);
+
+	template_context ctx;
+	template_init(&ctx);
+
+	ctx.user.z = z;
+	ctx.user.referenced = false;
+
+	int e = template_execute(&ctx, data, len, &noff);
+	if(e <= 0) {
+		msgpack_zone_free(z);
+		return false;
+	}
+
+	if(off != NULL) { *off = noff; }
+
+	result->zone = z;
+	result->data = template_data(&ctx);
+
+	return true;
+}
+
diff --git a/cpp/src/zone.c b/cpp/src/zone.c
index 85de765a..8cc8b0de 100644
--- a/cpp/src/zone.c
+++ b/cpp/src/zone.c
@@ -214,6 +214,7 @@ msgpack_zone* msgpack_zone_new(size_t chunk_size)
 
 void msgpack_zone_free(msgpack_zone* zone)
 {
+	if(zone == NULL) { return; }
 	msgpack_zone_destroy(zone);
 	free(zone);
 }