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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KDE Linux
KDE Linux is a user-focused, general-purpose Linux distribution. It is built by KDE and it is meant to showcase the best implementation of everything KDE has to offer, using the most advanced technologies.