Script to uninstall Nix from Ubuntu, tested with Ubuntu 22.04

uninstall_nix.sh

#!/bin/sh
# Uninstall Nix, tested with Ubuntu 22.04

# For your .bashrc and .zshrc, manually edit them to remove Nix related lines

for i in {1..32}; do sudo userdel nixbld${i}; done

sudo groupdel nixbld

sudo rm -rf /etc/nix /nix /var/root/.nix-profile /var/root/.nix-defexpr /var/root/.nix-channels \
    ~/.nix-profile ~/.nix-defexpr ~/.nix-channels /etc/systemd/system/nix-daemon.service \
    /etc/systemd/system/nix-daemon.socket /etc/bash.bashrc.backup-before-nix /etc/zsh/zshrc.backup-before-nix