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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MocaccinoOS
MocaccinoOS is an independently-developed Linux distribution that has its origins in source-based Gentoo Linux and Sabayon Linux. It uses a custom-built package manager called "Luet", which acts as a front-end for container-based software.