SystemJS

SystemJS 0.20.0-alpha.1 is now available with performance improvements and Web Assembly support. Try it out here.

Universal dynamic module loader - loads ES6 modules, AMD, CommonJS and global scripts in the browser and NodeJS.

• Loads any module format with exact circular reference and binding support.
• Loads ES6 modules compiled into the System.register bundle format for production, maintaining circular references support.
• Supports RequireJS-style map, paths, bundles and global shims.
• Loader plugins allow production resource loading and custom transpilation dev workflows.

Built with the ES Module Loader project, based on principles and APIs from the WhatWG Loader specification, modules in HTML and NodeJS.

~14KB minified and gzipped, runs in IE9+ and NodeJS.

For discussion, join the Gitter Room.

Documentation

• ES6 Modules Overview
• SystemJS Overview
• Config API
• Module Formats
• Production Workflows
• System API
• Creating Plugins

Basic Use

Browser

<script src="system.js"></script>
<script>
  SystemJS.import('/js/main.js');
</script>

The above will support loading all module formats, including ES Modules transpiled into the System.register format.

To load ES6 code with in-browser transpilation, ne of the following transpiler plugins must be configured:

• Babel
• TypeScript
• Traceur

NodeJS

To load modules in NodeJS, install SystemJS with:

  npm install systemjs

If transpiling ES6, also install the transpiler plugin, following the instructions from the transpiler project page.

We can then load modules equivalently in NodeJS as we do in the browser:

var SystemJS = require('systemjs');

// loads './app.js' from the current directory
SystemJS.import('./app.js').then(function(m) {
  console.log(m);
});

If you are using jspm as a package manager you will also need to load the generated configuration. The best way to do this in node is to get your System instance through jspm, which will automatically load your config correctly for you:

var Loader = require('jspm').Loader;
var SystemJS = new Loader();

SystemJS.import('lodash').then(function (_) {
 console.log(_);
});

Promise Polyfill

SystemJS relies on Promise being present in the environment.

For the best performance in IE and older browsers, it is advisable to load a polyfill like Bluebird or es6-promise before SystemJS.

Plugins

Supported loader plugins:

• CSS
• LESS
• Image
• JSON
• Text
• Node Binary

Additional Plugins:

• Audio
• CoffeeScript
• Ember Handlebars
• Handlebars
• HTML
• Image (lazy)
• Jade
• Jade VirtualDOM
• jst
• JSX
• Markdown
• raw
• SASS
• SCSS
• sofe
• svelte
• SVG
• WebFont
• WebWorkers
• YAML

Guides:

• Using plugins
• Creating plugins

Running the tests

  npm run build && npm run test

License

MIT