Hey!
I have started Developer hub on meta [1] - it's page for developers (not only php) who are looking for some project they can participate on, I am myself a developer of huggle (utility used on wikipedia for reverting vandalism, written in c#) and it's really hard to look for more devs who could join us, so I guess this could help a bit, especially if there are people who know other languages than php and are looking for projects they could work on. Feel free to improve that page or insert other projects, like AWB, etc. I don't even know what all tools we are using on wikimedia so it would do to have it all on one place.
Thanks!