diff --git a/response_writer.go b/response_writer.go
index 9035e6f1..142a7cc5 100644
--- a/response_writer.go
+++ b/response_writer.go
@@ -44,6 +44,9 @@ type ResponseWriter interface {
 
 	// Pusher get the http.Pusher for server push
 	Pusher() http.Pusher
+
+	// Unwrap get the underlying http.ResponseWriter
+	Unwrap() http.ResponseWriter
 }
 
 type responseWriter struct {