I've experimentally created a section on the code4lib wiki for "Patterns for Collaborative Code". Design Patterns (or "architectural patterns", or "good rules of thumb") to make your open source 'more open', more amenable to distributed development and use at multiple institutions without forking.
The idea is that we can share and develop collective knowledge about how to make our library-sector-originated open source more suitable for distributed shared open source. After some of us noted that there were some tricks and wisdom to it, it didn't happen automatically out of the box.
Much of what's there now was taken with permission from a nice blog post by Bill Dueber, thanks Bill!
So this is an experiment to see if it ends up being useful.
Please feel free to add content, edit content, completely restructure the whole thing, or do whatever you want to it. It's a wiki on purpose!