Some good pointers and links here, surprisingly they miss both my favourite approaches. 1. If it's on Github, find an issue that seems up your alley and check

Some good pointers and links here, surprisingly they miss both my favourite approaches. 1. If it's on Github, find an issue that seems up your alley and check the commits against it. Or the commit log in general for some interesting commits. I often use this approach to guide other devs to implement a new feature using nothing more than a previous commit or issue as a reference and starting point. 2. Unit tests are a great way to get jump started. It functions as a comprehensive examples reference--having both simple and complex examples and workflows. Not only will it contain API examples but it will also let you use experiment with the library using the unit test code as a sandbox.