Managarm: microkernel-based OS with fully asynchronous I/O

Ah, another microkernel-based hobby operating system. The more, the merrier - and I mean this, without a hint of sarcasm. There's definitely been a small resurgence in activity lately when it comes to small hobby and teaching operating systems, some of which are exploring some truly new ideas, and I'm definitely here for it. Today we have managarm.

Some notable properties of managarm are: (i) managarm is based on a microkernel while common Desktop operating systems like Linux and Windows use monolithic kernels, (ii) managarm uses a completely asynchronous API for I/O and (iii) despite those internal differences, managarm provides good compatibility with Linux at the user space level.

managarm GitHub page

It's a 64bit operating system with SMP support, an ACPI implementation, networking, USB3 support, and, as the quoted blurb details, a lot of support for Linux and POSIX. It can already run Weston, kmscon, and other things like Bash, the GNU Coreutils, and more. While not explicitly mentioned, I assume the best platform to run managarm on are most likely virtualisation tools, and there's a detailed handbook to help you along during building and using this new operating system.