After a day and a bit of not doing that pesky computery stuff Istarted to filter through my notebook. Put together a small patch for perl 5.005_03 to get it building on newer systems, sent it to p5p and started to duck and cover.
Also in my book of notes was a mutating itch to come up with a portable way of describing/diffing database schemas. It turns out that's what Alzabo is, rather than just something to steal build code from.
The resulting script is pleasingly simple: http://unixbeard.net/svn/richardc/misc/alz_diff