to install nix succesfully on my laptop I had to do the following steps:

guix install nix

nix-channel --list

if nixpkgs is not in channel then add

nix-channel --add https://nixos.org/channels/nixpkgs-unstable

sudo nix-channel --update --verbose

now change the group and ower of /nix

cd /nix/

sudo chown -R {your user name} ./var

sudo chown -R {your user name} ./store

sudo chgrp -R users ./var

sudo chgrp -R users ./store

now update the channels

nix-channel --update --verbose

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then install say firefox

nix-env -iA nixpkgs.firefox

Let me check my notes ths weekend and get back to you.

I use nix for any packages I can’t get from guix repos. So that’s an option too.

I’ve been using linux as my only OS since 2019 and like you came to the conclusion that it’s come a long way and is totally a viable option instead of windows.

Linux is great at running on old HW. I have a desktop I built in 2009 that runs linux.