The source is available on github. There are two main branches: master (stable, only updated when ready for release) and develop (unstable, has all the new features first). Occasionally, contributors will add new updates on their own bleeding-edge branches. By default, all releases are compiled from the stable branch; if you wish to use a branch with more experimental features, you will have to build them from source. Building instructions are available for Windows, Linux and OS X. On Linux, please note that you will need the zlib1g-dev package and multiple 32-bit libraries.