gittup - http://gittup.org/gittup
gittup is a small linux distribution. It is designed to show the power of the combination of git and tup. Git is a distributed version control system. Tup is a file-based build system for Linux, OSX, and Windows. This unique combination allows you to easily change parts of the system, track them by git, and recompile the needed parts of this distribution using tup.
See instructions at http://gittup.org/gittup/