Very simple version of Isolates.

runtime/bin/vmservice/vmservice.dart

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library vmservice;
 
 import 'dart:async';
 import "dart:convert";
 import 'dart:isolate';
 import 'dart:typed_data';
@@ skipping 13 matching lines @@
     switch (code) {
       case Constants.ISOLATE_STARTUP_MESSAGE_ID:
         runningIsolates.isolateStartup(sp, name);
       break;
       case Constants.ISOLATE_SHUTDOWN_MESSAGE_ID:
         runningIsolates.isolateShutdown(sp);
       break;
     }
   }
 
-  void messageHandler(message, SendPort replyTo) {
+  void messageHandler(message) {
     if (message is List && message.length == 3) {
       controlMessageHandler(message[0], message[1], message[2]);
     }
   }
 
   VMService._internal() {
-    port.receive(messageHandler);
+    port.listen(messageHandler);
   }
 
   factory VMService() {
     if (VMService._instance == null) {
       VMService._instance = new VMService._internal();
     }
     return _instance;
   }
 }
 
 void sendServiceMessage(SendPort sp, ReceivePort rp, Object m)
     native "SendServiceMessage";