A hobby operating system, not written in Rust, not targeting Qemu, not targeting a Raspberry Pi. Yes, it still happens.
Serena OS is what you get when modern operating system design and implementation meets vintage hardware like the Amiga computers. It is based on dispatch queues rather than threads, supports multiple users, is inspired by POSIX, yet retains its own character, is strongly object-oriented in terms of design and implementation and prepared for a cross platform future.
↫ Serena OS GitHub page
Serena OS supports most (all?) of the classic Amigas, but the 500, 600, and 2000 need at least 1MB of RAM and a 68020 accelerator. It has code privilege separation between kernel and userspace, basic memory management, its own custom file system, drivers for input devices and graphics, an interactive console with VT52 and VT100 support, and much more. It also comes with a C99-compatible libc, and has its own shell.
Note that “AI” chatbot Claude is listed as a contributor to the project.
Looked for where the slop was, it was from a single pull request from an outside user that was accepted: https://github.com/dplanitzer/Serena/pull/22