Re:gasp--a mess of shell scripts (Score 2, Informative)

From the cvs info pages:

CVS started out as a bunch of shell scripts written by Dick Grune, posted to the newsgroup `comp.sources.unix' in the volume 6 release of December, 1986. While no actual code from these shell scripts is present in the current version of CVS much of the CVS conflict resolution algorithms come from them.

A "mess of shell scripts" can be very useful for a proof-of-concept.