>And what if what you're doing is just a quick, one month project? Is it likely you must absolutely dig into the sources then? I would say no.

You would be surprised. I can't even count on one hand the number of times I've send a patch upstream within the first 2 hours of using a new dependency.

I don't really care how long he spent on it. It was a waste of 4 years if it's just going to be proprietary.