AutobahnJS is a JavaScript client library that implements The WebSocket Application Messaging Protocol (WAMP)

Usage no npm install needed!

<script type="module">
  import webevtAutobahnjs from 'https://cdn.skypack.dev/@webevt/autobahnjs';



AutobahnJS is a JavaScript client library that implements The WebSocket Application Messaging Protocol (WAMP):

  • implements WAMP v1, works with any WAMP server
  • provides asynchronous RPC and PubSub messaging patterns
  • easy to use Promise-based API
  • pluggable promises/deferreds: use when.js (built-in), jQuery, Dojo or others
  • flexible, automatic reconnect
  • session authentication (WAMP-CRA)
  • no dependencies
  • tiny size (97kB source, 27kB minified, 9kB compressed)
  • Open-Source (MIT License)

Get it

You can link to the latest prebuilt AutobahnJS release hosted on Amazon S3 here

  1. Production (minimized and gzipped)
  2. Production (only minimized)
  3. Development

What is that?

WebSocket is already built into modern browsers and provides bidirectional low-latency messaging.

However, as such, it is quite low-level. Web apps often have a need for higher level messaging patterns:

  • Publish & Subscribe
  • Remote Procedure Calls

This is where WAMP enters. WAMP runs on top of raw WebSocket and provides asynchronous RPC and PubSub.

Technically, WAMP is a proper WebSocket subprotocol that uses JSON as message serialization format. WAMP was designed to be easy to use and simple to implement.

AutobahnJS implements WAMP in JavaScript to be used in browser based applications.

ExtJS Extension

AutobahnExtJS provides and Autobahn/WAMP proxy and support code for Sencha ExtJS. Please see the autobahnextjs folder for code and more information.

Where to go

For more information, including getting started, tutorials and reference documentation, please visit the project's homepage.

Get in touch

Get in touch on IRC #autobahn on chat.freenode.net or join the mailing list.


AutobahnJS includes code from the following open-source projects

Special thanks to the Coders with an Unhealthy Javascript Obsession for creating when.js - A lightweight Promise and when() implementation, plus other async goodies.


Building AutobahnJS will create a single file, minimized version of the library.

To build, you will need

SCons is a Python based build tool, so you will need Python as well.

Set environment variables:

  1. JAVA_HOME pointing to your Java run-time, e.g.

    C:\Program Files\Java\jre7

  2. adding Python & Python scripts to PATH, e.g.


  3. JS_COMPILER pointing to the Google Closure compiler.jar

    C:\Program Files\Google Closure\compiler.jar

Now clone the repo:

git clone git://github.com/tavendo/AutobahnJS.git

You need to include the submodules (i.e. currenlty when.js):

cd AutobahnJS
git submodule init

and then update them

git submodule update 

Updating CryptoJS needs to be done manually, since they are not on Git.

For a release version, set the appropriate AutobahnJS version in 'version.txt', e.g

vi version.txt

Scons currently needs to be run from the Windows shell, so open one, go to the AutobahnJS directory, and run


This will produce 2 files


To clean up your build

scons -uc


Tavendo provides hosting of AutobahnJS on Amazon S3 at:


Set AWS credentials in $HOME/.boto (or C:\Users\johndoe\.boto for Windows):

aws_secret_access_key = 0123456789ABCDEFGHJIKLMNOPQRTUVXYZ

You will also need Boto installed:

easy_install boto

To publish, then do

scons publish