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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FydeOS
FydeOS, developed by Fyde Innovations, is a lightweight operating system that carries a Linux kernel, a browser platform and a container technology driver. It is very similar to Google ChromeOS in use.