Guix is a full open source Linux distribution approved by the FSF, meaning it's fully free. However, for many people this will mean the drivers requiring firmwares won't work and their usual software won't be present (like Firefox isn't considered free because of trademark issue).
A group of people is keeping a parallel repository for Guix to add some not-100% free stuff like kernel with firmware loading capability or packages such as Firefox, this can be added to any Guix installation quite easily.
Most of the code and instructions you will find here come from the nonguix README, you need to add the new channel to download the packages or the definitions to build them if they are not available as binary packages (called substitutions) yet.
Create a new file /etc/guix/channels.scm with this content:
(cons* (channel
(name 'nonguix)
(url "https://gitlab.com/nonguix/nonguix")
;; Enable signature verification:
(introduction
(make-channel-introduction
"897c1a470da759236cc11798f4e0a5f7d4d59fbc"
(openpgp-fingerprint
"2A39 3FFF 68F4 EF7A 3D29 12AF 6F51 20A0 22FB B2D5"))))
%default-channels)
And then run "guix pull" to get the new repository, you have to restart "guix-daemon" using the command "herd restart guix-daemon" to make it accounted.
If you use this repository you certainly want to have the kernel provided that allow loading firmwares and the firmwares, so edit your /etc/config.scm
(use-modules (nongnu packages linux)
(nongnu system linux-initrd))
(operating-system ;; you should already have this line
(kernel linux)
(initrd microcode-initrd)
(firmware (list linux-firmware))
#...
Then you use "guix system reconfigure /etc/config.scm" to rebuild the system with the new kernel, you will certainly have to rebuild the kernel but it's not that long. Once it's done, reboot and enjoy.
You should also have packages available now. You can enable the channel for your user only by modifying ~/.config/guix/channels.scm instead of the system wide /etc/channels.scm file. Note that you may have to build the packages you want because the repository doesn't build all the derivations but only a few packages (like firefox, keepassxc and a few others).
Note that Guix provide flatpak in its official repository, this is a workaround for many packages like "desktop app" for instant messaging or even Firefox, but it doesn't integrates well with the system.
There is also a dedicated gaming channel!
The nonguix repository is a nice illustration that it's possible to contribute to a project without forking it entirely when you don't fully agree with the ideas of the project. It integrates well with Guix while being totally separated from it, as a side project.
If you have any issues related to this repository, you should seek help from the nonguix project and not Guix because they are not affiliated.