Fiwix: A Lightweight, POSIX-Compliant Open-Source OS Kernel

Fiwix is a lightweight, open-source operating system kernel based on the UNIX architecture and fully POSIX-compliant. With under 50K lines of code, it's designed for educational purposes and hobbyists. Built as a monolithic kernel in ANSI C for the i386 architecture, it boasts compatibility with a large base of existing GNU applications. FiwixOS, a distribution based on the Fiwix kernel, includes a GNU toolchain, libraries, and other open-source software. It uses Newlib as its standard C library and Ext2 as its primary filesystem. The developers encourage users to test, provide feedback, and contribute to improve Fiwix and FiwixOS.