MOROS
MOROS: Obscure Rust Operating System
...It targets computers with an x86-64 architecture and a BIOS, typically from 2005 to 2020. It also runs well on most emulators. MOROS is open source. You can build or download an image. Check out the manual for details on how to use it. MOROS is text-based and draws inspiration from Unix and DOS to provide a simple and efficient environment for computing and communication from the command line. Each program is designed to ensure a cohesive user interface across the entire system. The shell is the hearth of MOROS, used to navigate the filesystem and run other programs.