He also mentioned it took 2 months. I’m actually wondering how long it would take to do the Linux to BSD port by eyeball, or at least ai assisted. Probably not that much longer? I guess it depends on wall time vs real time.

Most hardware drivers are simpler than people expect. The hardware is usually designed to do the sensible thing in a straightforward way, and you're just translating what the OS wants into a bunch of bits you need to write to the right hardware register.

On the flip side, the perceived barrier is high. Most folks don't have an intuitive sense of how the kernel or "bare metal" environment differs from userland. How do you allocate memory? Can you just printf() a debug message? How to debug if it freezes or crashes? All of these questions have pretty straightforward answers, but it means you need to set aside time to learn.

So, I wouldn't downplay the value of AI for the same reason I wouldn't downplay it with normal coding. It doesn't need to do anything clever to be useful.

That said, for the same reasonss, it's harder to set up a good agent loop here, and the quality standard you're aiming for must be much higher than with a web app, because the failure mode isn't a JavaScript error, but possibly a hard hang.

I estimate two weeks from having never seen kernel source to something reasonably stable based on experience with block devices/raid controllers. But I knew a bit of C (had patches merged into SVN, Exim4, etc).