I too have an odd obsession with keeping everything in 1 file.

I recently (as an experiment) exclusively vibe-coded an Asteroids clone (with a couple of nifty additions), all in a single HTML file, including a unit test suite, which also works on either desktop or mobile: https://github.com/pmarreck/vibesteroids/blob/yolo/docs/inde...

Playable version (deployed via github docs) is here: https://pmarreck.github.io/vibesteroids/ Hit Esc to pause and see instructions (pause should be automatic on mobile; can re-pause by tapping top center area).

Type shift-B (or shake mobile device... you also would have had to approve its ability to sense that on iOS) to activate the "secret" ability (1 per life)

No enemy UFO's to shoot (yet) but the pace does quicken on each level which feels fun.

It doesn't update itself, however... (and I just noticed it has a test fail, and a test rendering bug... LOL, well at least the tests are valid!)