diff --git a/core/transport/websocket_transport.go b/core/transport/websocket_transport.go
index ec93c58..cbde2c3 100644
--- a/core/transport/websocket_transport.go
+++ b/core/transport/websocket_transport.go
@@ -26,6 +26,7 @@ type wsServerTransport struct {
 	l        net.Listener
 	m        map[*Transport]struct{}
 	done     chan struct{}
+	mux      *http.ServeMux
 }
 
 func (ws *wsServerTransport) Close() (err error) {
@@ -80,8 +81,11 @@ func (ws *wsServerTransport) Listen(ctx context.Context, notifier chan<- bool) (
 		}
 	}()
 
-	mux := http.NewServeMux()
-	mux.HandleFunc(ws.path, func(w http.ResponseWriter, r *http.Request) {
+	if ws.mux == nil {
+		ws.mux = http.NewServeMux()
+	}
+
+	ws.mux.HandleFunc(ws.path, func(w http.ResponseWriter, r *http.Request) {
 		// upgrade websocket
 		c, err := ws.upgrader.Upgrade(w, r, nil)
 		if err != nil {
@@ -103,7 +107,7 @@ func (ws *wsServerTransport) Listen(ctx context.Context, notifier chan<- bool) (
 		}
 	})
 
-	err = http.Serve(ws.l, mux)
+	err = http.Serve(ws.l, ws.mux)
 	if err == io.EOF || isClosedErr(err) {
 		err = nil
 	} else {
@@ -138,8 +142,12 @@ func (ws *wsServerTransport) putTransport(tp *Transport) bool {
 	}
 }
 
+func NewWebsocketServerTransportWithMux(f ListenerFactory, path string, upgrader *websocket.Upgrader, mux *http.ServeMux) ServerTransport {
+	return NewWebsocketServerTransport(f, path, upgrader, mux)
+}
+
 // NewWebsocketServerTransport creates a new server-side transport.
-func NewWebsocketServerTransport(f ListenerFactory, path string, upgrader *websocket.Upgrader) ServerTransport {
+func NewWebsocketServerTransport(f ListenerFactory, path string, upgrader *websocket.Upgrader, mux *http.ServeMux) ServerTransport {
 	if path == "" {
 		path = defaultWebsocketPath
 	}
@@ -158,6 +166,7 @@ func NewWebsocketServerTransport(f ListenerFactory, path string, upgrader *webso
 		f:        f,
 		m:        make(map[*Transport]struct{}),
 		done:     make(chan struct{}),
+		mux:      mux,
 	}
 }
 
@@ -174,7 +183,7 @@ func NewWebsocketServerTransportWithAddr(addr string, path string, upgrader *web
 		}
 		return tls.NewListener(l, config), nil
 	}
-	return NewWebsocketServerTransport(f, path, upgrader)
+	return NewWebsocketServerTransport(f, path, upgrader, nil)
 }
 
 // NewWebsocketClientTransport creates a new client-side transport.