Would you like to contribute to the development of Mu? (If you think this is only something for experienced developers, please reconsider, there are plenty of ways to contribute to Mu, no matter your level of experience or skill set).
Our technical documentation is hosted on the wonderful service that is Read the Docs (http://mu.readthedocs.io/). Not only does it contain details needed in order to make code contributions to Mu, but it outlines plenty of other ways in which you can contribute (including making updates to this website). Finally it provides a guide to our processes and expectations for the various types of contribution you can make to Mu.
The source code is hosted on GitHub.
If in doubt, just ask in our discussion area and someone will be able to point you in the right direction.