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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CachyOS
CachyOS is a Linux distribution based on Arch Linux. It focuses on speed and security optimisations - the default Linux kernel is heavily optimised using the BORE (Burst-Oriented Response Enhancer) scheduler, while the desktop packages are compiled with LTO, x86-64-v3 and x86-64-v4, Zen 4 optimization, security flags and performance improvements.