The excitement between successful compilation and running a program -- only to find out that it emits a stream of nonsense to the console instead of the answer

The excitement between successful compilation and running a program -- only to find out that it emits a stream of nonsense to the console instead of the answer you expect: but that's no problem, ctrl-c and back to the code. The satisfaction of opening a perfectly-tuned merge request with a minimal diff and glowing momentarily to yourself as tests all begin to pass (before realizing that there's an embarrassing typo in the title text). The feel-good factor from optimizing runtime and energy usage for your most prized simulation library (despite the fact that it's only used by yourself and perhaps one other egg avatar who starred your repository). The endless mental battle against an onslaught of awful, awful code and technology decisions from employers and the Internet, yet paired with evident continued emergence of more reliable, higher quality and more freely available and equitable tools over time. And being able to participate in all that in a small way.