Contributions are very welcome. To make the process as easy as possible please follow these steps:

Open an issue detailing the bug you've found, or the feature you wish to add. Simplified working examples using something like jsFiddle make it easier to diagnose your problem.
Add tests for your code (so I don't accidentally break it in the future).
Don't change version numbers or make new builds as part of your changes.
Don't change the built versions of the library; only make changes to code in the lib directory.

Developer Dependencies

A JavaScript runtime is required for building the library.

Run the tests (using PhantomJS):

make test

The tests can also be run in the browser by starting the test server:

make server

This will start a server on port 3000, the tests are then available at /test.