SuriyaaOS - A simple, basic UNIX-like operating system built by Suriyaa Kudo. ToaruOS - An open-source UNIX-like operating system with GUI and network support. Developed at the University of Illinois. Genode - An open source OS framework, intended to build UNIX-like environment over several microkernels. Redox - A UNIX-like operating system written in Rust programming language. Muen | SK - An open source OS kernel that has been formally proven to contain no runtime errors at the source code level. PIOS - A small UNIX-like OS written by Bryan Ford at Yale University for educational purposes.