F-Zero X on Nintendo 3DS

A post-mortem of porting G-Diffuser, the F-Zero X decompilation, to the Nintendo 3DS — v1.0.0, covering both the original 24-day sprint that put it on a New 3DS at 60 fps in 3D (2026-08-11 to 09-03) and the 43-day second phase that added Old 3DS support, a native renderer, and the Expansion Kit (2026-09-07 to 10-19). One person directed throughout; one long-lived Claude session orchestrated; 147 subagents built the first phase and many more carried the second.

The console went from a black screen to a native-60 stereoscopic racer, then from a New-3DS-only build to a four-way release covering both consoles with and without the 64DD expansion.

The clips and photos below are from v0.9 (2026-09), before DASH replaced the debug console on the bottom screen.

Three released console builds from one source tree, all booting from the HOME menu (.cia) or the homebrew launcher (.3dsx): the base game for Old 3DS / 2DS and for New 3DS / New 2DS XL, and a New 3DS build with the 64DD Expansion Kit (course editor and machine creator, playable with a user-supplied disk image). Every build reads prebaked asset archives from the SD card — no ROM or disk image ever ships with the game.

They play the whole game: Grand Prix, Time Trial, Practice, Death Race, and the machine editor screens, with music and effects on the real DSP, stereoscopic 3D on the slider, a bottom-screen dashboard with three HUD layouts and an idle view outside races, and clean HOME suspend, resume, close, lid sleep and power-off. The New 3DS build keeps the native-60 frame pacing the first phase reached; the Old 3DS build gets to a comparable result by a different route. At v1.0.0, with no ini, both builds default to that same route: the native renderer ([perf] preset = auto). The New 3DS's first-phase render-thread/per-draw-stereo path is still built in and reachable with an explicit ini, but is no longer the default — see Frontier and Pushing the boundaries for the two builds compared side by side.

Not originally planned; it ran 09-07 to 10-19, 43 calendar days.

See Agentic workflow for how the second phase was run and Old 3DS for the full campaign, card by card.