I just use GitHub issues and Google Tasks. But more importantly, I try very hard to avoid reinventing wheels, I'm always on the lookout for original code I can

I just use GitHub issues and Google Tasks. But more importantly, I try very hard to avoid reinventing wheels, I'm always on the lookout for original code I can rip out and replace with some industry standard thing, etc. I can afford to be inefficient with my side projects, since there's really only a few nontrivial pieces, and the whole dev workflow is kind of chosen for you with some frameworks.