anchor.diff:        return;
       }
   
  -    if (request.headers['x-github-event'] == null) {
  +    if (request.headers.value("X-GitHub-Event") == null) {
         request.response
           ..write("X-GitHub-Event must be specified.")
           ..close();
  
positive.code: }
  
  class HookEvent {
    final String event;
    final Map<String, Object> data;
  
    HookEvent(this.event, this.data);
  }
  
negative.code:     }
  
      request.transform(UTF8.decoder).join().then((content) {
        _eventController.add(new HookEvent.fromJSON(request.headers.value("X-GitHub-Event"), JSON.decode(content)));
        request.response
          ..write(JSON.encode({"handled": _eventController.hasListener}))
          ..close();
  