Yeah just had Codex/Gemini write me nrf52 bootloader that fit in under 4k flash sector size with OTA and DFU support (well, app does OTA download then the bootloader validates and decompresses the image). Works best if you let them use OpenOCD on a real device, then they can iterate until it starts working.

I didn't even need that bootloader, just didn't like the fact that Adafruit one takes too much space :)