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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ZimaOS
ZimaOS is an independently-developed, Linux-based operating system for personal servers and network-attached storage (NAS) devices. It features system-level support for remote access, RAID configuration, over-the-air (OTA) updates, and a browser-based user interface for managing the server.