packages config is only for dealing with code that is laid out using a package directory structure like the Packages spec mentioned on the CommonJS site, it is not about understanding how to load a CommonJS-formatted module. If you want that, then cajon might be a better loader option.

Closing as I think the cajon loader is a better fit for the described use case.

The document described folder structure, but it never said what the cart/main.js content should look like.

it is

export.foo = 'bar'  // I think this is a CommonJS module define

or

define(function(require, exports) {
//...
})

RequireJS supports loading modules that are in a CommonJS Packages directory structure, but some additional configuration needs to be specified for it to work.

But what a RequireJS supported CommonJS Packages's main javascript file content look like, docs never metioned.

That makes sense, will reopen to track a doc fix to explain more.

Any intention to address this? Like reporter @guileen I've read all the documentation and I'm still baffled.

I'm trying to use RequireJS to load the Node modules 'events' and 'util' but they just throw the error 'module is not defined'.

This seems pretty well covered under http://www.requirejs.org/docs/commonjs.html, which is linked from the sidebar ("CommonJS Notes") and from the package config API section:

IMPORTANT NOTES

• While the packages can have the CommonJS directory layout, the modules themselves should be in a module format that RequireJS can understand. Exception to the rule: if you are using the r.js Node adapter, the modules can be in the traditional CommonJS module format. You can use the CommonJS converter tool if you need to convert traditional CommonJS modules into the async module format that RequireJS uses.