vcprompt prints a short string, to be included in your shell prompt, with barebones information about the current working directory for various version control systems. It is designed to be small and lightweight rather than comprehensive. It has varying degrees of recognition for Mercurial, Git, Subversion, CVS, and Fossil working copies.
Fubsy is a tool for efficiently building software. In concrete terms, it lets you conditionally (re)build targets from sources based on which sources have changed since the last build. Typically, targets and sources are all files in a directory tree. In theory, they can be any resource on a computer. More abstractly, Fubsy is an engine for conditional execution of actions based on the dependencies between related resources.