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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Devuan GNU+Linux
Devuan GNU+Linux is a Linux distribution forked from Debian in 2015. The project's primary goal is to provide a variant of Debian without the complexities and dependencies of systemd, an init system and services manager originally developed by Red Hat and later adopted by most other Linux distributions.