diff --git a/socket.io/socket.io.d.ts b/socket.io/socket.io.d.ts
index ad95f39ef3..abc554c065 100644
--- a/socket.io/socket.io.d.ts
+++ b/socket.io/socket.io.d.ts
@@ -47,7 +47,8 @@ interface SocketIOStatic {
 declare namespace SocketIO {
 
 	interface Server {
-
+		engine: { ws: WebSocketServer };
+		
 		/**
 		 * A dictionary of all the namespaces currently on this Server
 		 */