Helma NG implements the Securable Modules proposal defined by the ServerJS working group that describes an interoperable JavaScript module system. Helma NG even goes beyond that by providing each module its own top-level scope, allowing for full namespace isolation similar to the way Python does.
Modules are also used as building blocks for web applications. Web developers simply map modules to the URI namespace of their web app and all exported functions in the module will be callable through the web.
For example, the following code in a web app's config.js mapps the module named "webmodule" to /mount/point/:
exports.urls = [
[ '/mount/point', 'webmodule' ]
]You can learn more about modules on the Helma NG wiki.