[oddlyaromatic]

Not tech, but I have a full time job (managing disability support programs, 40+ hours a week) and a part time job (10-20 hours/week running a small one-person office), with occasional work on the road as a music tour manager (4 or 5 weekends a year). I don't always tell the main full time employer what I'm doing when I request time off, but it's always worked out so far. Main problem is tiredness when you end up working many days without actual time off. I'd be careful of making a solid hourly commitment to a second job. I just about get away with it because my employers are flexible and care more that work gets done than where I am or how I do it.