Show HN: My from-scratch OS kernel that runs DOOM

Great work, I would love to have the skills to do something like this, but I can see you had to read lots of specifications to achieve this and thats my weakest point.

One silly question you may know: Imagine you wanted to use GPU acceleration, even in the smallest form. How hard would it be to build a driver for the GPU? Do you think there is good documentation about it?

Umm that's probably the extreme end of OSDev which I likely wouldn't be able to do, at least not for a driver you can buy. Qemu's emulated GPU is documented decently and could be possible, but things like nvidia GPUs are badly documented (and until recently, the docs were fully closed source) - even Linux has issues with this (and I actually see a few other hobby OS devs who just use Linux's GPU drivers in the end). There aren't a lot of things I've marked as near impossible but writing a genuinely decent GPU driver for a common GPU isn't really something I imagine I'll ever be able to do sadly.