Yeah, since I retired four years ago the
only things I've worked on have been like that.
(1) A script to solve a resource-allocation problem in Grim Dawn (ARPG).
(2) A tiny bit of code added to Garmin's developer kit, to pick apart their .fit files and show me some running metrics that were hard to get at otherwise.
I do have one other thing I've been wanting to do recently, which might even be worth putting out there if/when I finish it. Then again, maybe not. Having been a maintainer for a project with hundreds of contributors before, I can say that coding for oneself feels very liberating. Only as much infrastructure and process as necessary to get the job done. No need to deal with feature requests or bug reports. No commit races, or battles in code-review comments. You know the requirements perfectly (or have a perfectly compliant customer who is willing to change) so if you want to take a short cut you can. I was often a stickler for doing things "the right way" when I was working, but part of the reason I left is that my work seemed to be all about shepherding the process and not the joy of making code grow and do new things. Having total freedom on a project, even a small one, is good balm for a jaded programmer's soul.