Rebuild is a recreation of the famous build/bud, based on the DMD frontend. It was written because of general unhappiness with build/bud.
Rebuild is a component of DSSS, and so is available for download as part of DSSS at http://svn.dsource.org/projects/dsss/downloads/
There is a very sparse README for rebuild: http://www.dsource.org/projects/dsss/browser/trunk/rebuild/README .
rebuild uses configuration files for its targets. Nearly everything is configurable, so you can retarget it and even cross-compile.
The configuration directory is named rebuild.conf . You can either leave it next to the binary, or (if you install in a Unix style), rename it /etc/rebuild or ~/.rebuild .