This is something I had been working on for a while now (few years, even before things like Claude/Codex were considered "mainstream").
It's basically a Linx from Scratch (LFS), with a twist. Every part of the system (except the Linux kernel itself of course) is written entirely in Go. I've done similar things in the past with what GoNix is derived from, called uLinux, and some shell-script based LFS (but widely different then the book).
Anyway, GoNix is pretty neat (IMO), it runs https://gonix.dev itself! And it boots in roughly ~20ms in Vultr Cloud where I run the site from. I'm also using GoNix as the base OS for an appliance I'm building with OTA and A/B updates. So this isn't just a toy, it's quite serious really.
Target market/use-case is appliances and use-cases where you need a system to be quite small and quite fast to boot-up, e.g: Ephemeral CI/CD runners.