diff --git a/response_writer.go b/response_writer.go
index a40f5ba0..2c97e766 100644
--- a/response_writer.go
+++ b/response_writer.go
@@ -16,32 +16,6 @@ const (
 	defaultStatus = 200
 )
 
-type ResponseWriter interface {
-	http.ResponseWriter
-	http.Hijacker
-	http.Flusher
-	http.CloseNotifier
-
-	// Returns the HTTP response status code of the current request.
-	Status() int
-
-	// Returns the number of bytes already written into the response http body.
-	// See Written()
-	Size() int
-
-	// Writes the string into the response body.
-	WriteString(string) (int, error)
-
-	// Returns true if the response body was already written.
-	Written() bool
-
-	// Forces to write the http header (status code + headers).
-	WriteHeaderNow()
-
-	// get the http.Pusher for server push
-	Pusher() http.Pusher
-}
-
 type responseWriter struct {
 	http.ResponseWriter
 	size   int
@@ -115,10 +89,3 @@ func (w *responseWriter) CloseNotify() <-chan bool {
 func (w *responseWriter) Flush() {
 	w.ResponseWriter.(http.Flusher).Flush()
 }
-
-func (w *responseWriter) Pusher() (pusher http.Pusher) {
-	if pusher, ok := w.ResponseWriter.(http.ResponseWriter).(http.Pusher); ok {
-		return pusher
-	}
-	return nil
-}
diff --git a/response_writer_1.7.go b/response_writer_1.7.go
new file mode 100644
index 00000000..0ffa35b8
--- /dev/null
+++ b/response_writer_1.7.go
@@ -0,0 +1,33 @@
+// +build go1.7
+
+// Copyright 2018 Gin Core Team.  All rights reserved.
+// Use of this source code is governed by a MIT style
+// license that can be found in the LICENSE file.
+
+package gin
+
+import "net/http"
+
+// ResponseWriter ...
+type ResponseWriter interface {
+	http.ResponseWriter
+	http.Hijacker
+	http.Flusher
+	http.CloseNotifier
+
+	// Returns the HTTP response status code of the current request.
+	Status() int
+
+	// Returns the number of bytes already written into the response http body.
+	// See Written()
+	Size() int
+
+	// Writes the string into the response body.
+	WriteString(string) (int, error)
+
+	// Returns true if the response body was already written.
+	Written() bool
+
+	// Forces to write the http header (status code + headers).
+	WriteHeaderNow()
+}
diff --git a/response_writer_1.8.go b/response_writer_1.8.go
new file mode 100644
index 00000000..c80dc81e
--- /dev/null
+++ b/response_writer_1.8.go
@@ -0,0 +1,43 @@
+// +build !go1.7
+
+// Copyright 2018 Gin Core Team.  All rights reserved.
+// Use of this source code is governed by a MIT style
+// license that can be found in the LICENSE file.
+
+package gin
+
+import "net/http"
+
+// ResponseWriter ...
+type ResponseWriter interface {
+	http.ResponseWriter
+	http.Hijacker
+	http.Flusher
+	http.CloseNotifier
+
+	// Returns the HTTP response status code of the current request.
+	Status() int
+
+	// Returns the number of bytes already written into the response http body.
+	// See Written()
+	Size() int
+
+	// Writes the string into the response body.
+	WriteString(string) (int, error)
+
+	// Returns true if the response body was already written.
+	Written() bool
+
+	// Forces to write the http header (status code + headers).
+	WriteHeaderNow()
+
+	// get the http.Pusher for server push
+	Pusher() http.Pusher
+}
+
+func (w *responseWriter) Pusher() (pusher http.Pusher) {
+	if pusher, ok := w.ResponseWriter.(http.ResponseWriter).(http.Pusher); ok {
+		return pusher
+	}
+	return nil
+}