We have a rule that if you check in code, you have to maintain it. So I mostly code on the side. I don't check in code anymore.
Hackathons are these things where just all of the Facebook engineers get together and stay up all night building things. And, I mean, usually at these hackathons, I code too, just alongside everyone.
If there is a bug in your code than you have to drop everything you're doing and go fix it.