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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CuerdOS
CuerdOS is a Debian-based GNU/Linux distribution with focus on stability, efficiency and performance. It comes with a series of optimisations, such as performance and memory consumption improvements.