[klange]

When I started the project a decade ago, my aim was specifically to understand POSIX/Unix and to "learn by doing", so of course there's some POSIX-like elements underpinning the design. Back before I decided that literally anything can be in scope and was using third-party components, this aided in porting software, as other commenters have pointed out. These days, it gives more purpose to things I build for the OS if they can also reasonably be built for Linux or macOS - things like my editor (which I wrote for the OS and now use as my daily driver in Linux), or my Python knock-off.

As for the microkernel bit, this might sound like circular reasoning but I didn't go for a microkernel because no one really uses microkernels. It's not that I think microkernels are a bad idea, ToaruOS does push plenty of stuff into userspace. Rather, my main goal at the moment is to provide an educational resource that more accurately models the way "real" OSes work than the typical academic OS projects.