[msluyter]

A lot of projects I've worked on have utility libraries consisting of mostly stateless, pure functions -- I have a theory that these constitute some of the longest lived code. That, and database models, which tend to be easier to expand than to contract. I'd be curious to see some analysis along these lines.

[jtigger]

Nice hypothesis! Reminds me of the shearing layers from Foote & Yoder's "Big Ball of Mud" — http://www.laputan.org/mud/mud.html#ShearingLayers