RedoxOS! There’s been solid progress too, beyond just having a functional microkernel, they have many of the userspace tools/their version of coreutils, even a desktop environment already mostly implemented!

My understanding is that it shouldn’t be too bad to port some other things over as well. The main issue I had was just the lack of drivers, especially since it’s still tricky even on Linux, and the microkernel architecture (though more secure) also means there’s no way to reuse any of those from Linux