If I'm not hunting bugs (often of my own making), I generally get stuck on developing new systems for Outer Wilds. It often starts with a long discussion with the game designers, with me trying to suss out the parts that are important to me in terms of software design. Once all those requirements are sorted out, I get to implementing it in game:
*insert coffee*
*insert Hollywood hacking sequence*
*insert rage sequence*
*repeat above as many times as needed*
*insert Houston Mission Control Center celebration*
Inevitably after some play-testing, the game designers will come back with tweaks or fixes they want to make, and the whole software development cycle begins again. It's a story familiar to most programmers, I'm sure.