diff --git a/src/worker.ts b/src/worker.ts
index 8d23683..d081e86 100644
--- a/src/worker.ts
+++ b/src/worker.ts
@@ -26,40 +26,11 @@ ctx.get_stdin = get_stdin;
 // @ts-ignore: breaks typedoc
 let resolveInputReply: any;
 
-function postMessageToMain(message: any, channel: string) {
-  message.channel = channel;
-  message.type = message.header.msg_type;
-  ctx.postMessage(message);
-}
-
 async function loadCppModule(moduleFactory: any): Promise<any> {
   const options: any = {};
   return moduleFactory(options).then((Module: any) => {
     raw_xkernel = new Module.xkernel();
     raw_xserver = raw_xkernel.get_server();
-    raw_xserver!.register_js_callback(
-      (type: string, channel: number, message: any) => {
-        switch (type) {
-          case 'shell': {
-            postMessageToMain(message, 'shell');
-            break;
-          }
-          case 'control': {
-            throw new Error('send_control is not yet implemented');
-            break;
-          }
-          case 'stdin': {
-            postMessageToMain(message, 'stdin');
-            break;
-          }
-          case 'publish': {
-            // TODO ask what to do with channel
-            postMessageToMain(message, 'iopub');
-            break;
-          }
-        }
-      }
-    );
     raw_xkernel!.start();
   });
 }