System loader extension for flexible AMD & CommonJS support


For upgrading to SystemJS 0.16, see the ES6 Module Loader 0.16 release upgrade notes for more information, or read the updated Getting Started guide below.

Universal dynamic module loader - loads ES6 modules, AMD, CommonJS and global scripts in the browser and NodeJS. Works with both Traceur and Babel.

Designed to work with the ES6 Module Loader polyfill (9KB) for a combined total footprint of 16KB minified and gzipped.

Runs in IE8+ and NodeJS.

For discussion, see the Google Group.

For a list of guides and tools, see Third-Party Resources.

Download es6-module-loader.js into the same folder as system.js.

Load SystemJS with a single script tag:

<script src="system.js"></script>

It will then load es6-module-loader.js itself.

To load ES6, locate traceur.js in the baseURL path and it will be loaded when needed.

For use with Babel, locate the browser.js file at babel.js in the baseURL and set:

  System.transpiler = 'babel';

Alternatively a custom path to Babel or Traceur can also be set through paths:

  paths: {
    traceur: 'path/to/traceur.js'

To load modules in NodeJS, install SystemJS with:

  npm install systemjs traceur

(making sure to also install Traceur or Babel as needed, as they are not included as dependencies as of SystemJS 0.16)

We can then load modules equivalently to in the browser:

var System = require('systemjs');
 * Include
 *   System.transpiler = 'babel';
 * to use Babel instead of Traceur
// loads './app.js' from the current directory 
System.import('./app').then(function(m) {

If configuring the baseURL for use in Windows, prepend file: i.e.

 baseURL: 'file:' + path.resolve('../path')

Plugins handle alternative loading scenarios, including loading assets such as CSS or images, and providing custom transpilation scenarios.

Supported Plugins:

  • CSS System.import('my/file.css!')
  • Image System.import('some/image.png!image')
  • JSON System.import('some/data.json!').then(function(json){})
  • Text System.import('some/text.txt!text').then(function(text) {})

Additional Plugins:

  • CoffeeScript System.import('./!')
  • Jade
  • JSX System.import('template.jsx!')
  • Markdown System.import('app/some/project/!').then(function(html) {})
  • WebFont System.import('google Port Lligat Slab, Droid Sans !font')
  • Ember Handlebars System.import('template.hbs!')

Plugins are loaded from the module name of the extension. To set them up, you'll most likely want to add map configuration. For example:['css'] = 'path/to/css/plugin';

Loading through plugin is indicated with ! at the end of the name:

System.import('file.css!');      // will use the "css" plugin, assumed from the extension 
System.import('file.css!text');  // will use the "text" plugin, instead of checking the extension 

Read the guide here on creating plugins.

To install the dependencies correctly, run bower install from the root of the repo, then open test/test.html in a browser with a local server or file access flags enabled.