NixOS
NixOS is an independently developed GNU/Linux distribution that aims to improve the state of the art in system configuration management. In NixOS, the entire operating system, including the kernel, applications, system packages and configuration files, are built by the Nix package manager.
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Void
Void is an independently-developed, general-purpose operating system based on the monolithic Linux kernel. It features a hybrid binary/source package management system which allows users to quickly install, update and remove software, or to build software directly from sources with the help of the XBPS source packages collection.