Apps similar to GNU Guix include Linux Mint, which is free and open source. Other options are Ubuntu, Debian, Fedora and Arch Linux. You're spoiled for choice with Operating Systems like GNU Guix: we list more than 100 alternatives for Linux, Mac, self-hosting, Windows and the web.
An open-source OS for exploration, creation, and play. Kano OS is based on the Raspbian OS which itself is based on Debian, a Linux based operating system.
United Kingdom
Minoca OS is a general purpose operating system designed specifically for feature-rich embedded devices. It's got all the high-level functionality that you've come to expect from an operating system, but offers it in a fraction of the memory footprint.
Canada
Athena OS is an Arch-derived Linux distribution designed for penetration testing, bug-bounty hunting and InfoSec students. The distribution provides a way to connect directly to some of the e-learning hacking resources, such as Hack The Box, Offensive Security, PWNX and InfoSec...
Korora is an installable Fedora Remix Live USB image which aims to provide a complete out of the box experience for new users, including support for multimedia.
BSD-derived desktop OS designed for usability, featuring graphical ports management, GNUstep system configuration, standard tools for daily tasks including email, web browsing, and word processing, supporting multiple licenses like BSD, X.org, and GNUstep.
United States
The Zeal Operating System is a modernized, professional fork of the 64-bit Temple Operating System. Guiding principles of development include transparency, full user control, and adherence to public-domain/open-source implementations.
Peropesis is a small-scale, minimalist, command-line-based Linux operating system. It's an incomplete system, but it's constantly being improved. Also, it is a free operating system created from a free software.
instantOS is a Manjaro based distro that works out of the box but is still aimed at power users. Everything is lightning fast and works out of the box.
MorphOS is an AmigaOS-like computer operating system. It is a mixed proprietary and open source OS produced for the PowerPC processor based computers.
Germany
EU
Live bootable linux CD supported by US department of defense, featuring firefox, thunderbird, word processor, and reads USB flash drives.
Calculate Linux is based on Gentoo that is well known for its stability and great performance on a broad range of hardware: from Pentium Pro to modern CPUs.
Russia