Users & Groups copypasta.
useradd --create-home --groups sudo,adm $USER
* Good starting point for adding a user on *nix system/server.
sudo usermod -a -G dialout,plugdev $(whoami)
* Modifying an existing user's group memberships.
sudo useradd -m -G tty,libvirt,uucp,wheel,dialout -s /bin/zsh $USER
* Manjaro one-liner for setting default groups.
* (Arch's `UUCP` & setting the login shell.)
sudo usermod -a -G nintendo_switch $USER
* Homebrew Switch `udev` rules to allow running `nvidia tegra exploit` code w/o `root`