Uninstalling Nix

Multi User

Removing a multi-user installation depends on the operating system.

Linux

If you are on Linux with systemd:

1. Remove the Nix daemon service:

   sudo systemctl stop nix-daemon.service
   sudo systemctl disable nix-daemon.socket nix-daemon.service
   sudo systemctl daemon-reload
   

Remove files created by Nix:

sudo rm -rf /etc/nix /etc/profile.d/nix.sh /etc/tmpfiles.d/nix-daemon.conf /nix ~root/.nix-channels ~root/.nix-defexpr ~root/.nix-profile

Remove build users and their group:

for i in $(seq 1 32); do
  sudo userdel nixbld$i
done
sudo groupdel nixbld

There may also be references to Nix in

• /etc/bash.bashrc
• /etc/bashrc
• /etc/profile
• /etc/zsh/zshrc
• /etc/zshrc

which you may remove.

macOS

1. If system-wide shell initialisation files haven't been altered since installing Nix, use the backups made by the installer:

   sudo mv /etc/zshrc.backup-before-nix /etc/zshrc
   sudo mv /etc/bashrc.backup-before-nix /etc/bashrc
   sudo mv /etc/bash.bashrc.backup-before-nix /etc/bash.bashrc
   

   Otherwise, edit /etc/zshrc, /etc/bashrc, and /etc/bash.bashrc to remove the lines sourcing nix-daemon.sh, which should look like this:

   # Nix
   if [ -e '/nix/var/nix/profiles/default/etc/profile.d/nix-daemon.sh' ]; then
     . '/nix/var/nix/profiles/default/etc/profile.d/nix-daemon.sh'
   fi
   # End Nix
   

2. Stop and remove the Nix daemon services:

   sudo launchctl unload /Library/LaunchDaemons/org.nixos.nix-daemon.plist
   sudo rm /Library/LaunchDaemons/org.nixos.nix-daemon.plist
   sudo launchctl unload /Library/LaunchDaemons/org.nixos.darwin-store.plist
   sudo rm /Library/LaunchDaemons/org.nixos.darwin-store.plist
   

   This stops the Nix daemon and prevents it from being started next time you boot the system.

3. Remove the nixbld group and the _nixbuildN users:

   sudo dscl . -delete /Groups/nixbld
   for u in $(sudo dscl . -list /Users | grep _nixbld); do sudo dscl . -delete /Users/$u; done
   

   This will remove all the build users that no longer serve a purpose.

4. Edit fstab using sudo vifs to remove the line mounting the Nix Store volume on /nix, which looks like

   UUID=<uuid> /nix apfs rw,noauto,nobrowse,suid,owners
   

   or

   LABEL=Nix\040Store /nix apfs rw,nobrowse
   

   by setting the cursor on the respective line using the error keys, and pressing dd, and then :wq to save the file.

   This will prevent automatic mounting of the Nix Store volume.

5. Edit /etc/synthetic.conf to remove the nix line. If this is the only line in the file you can remove it entirely:

   if [ -f /etc/synthetic.conf ]; then
     if [ "$(cat /etc/synthetic.conf)" = "nix" ]; then
       sudo rm /etc/synthetic.conf
     else
       sudo vi /etc/synthetic.conf
     fi
   fi
   

   This will prevent the creation of the empty /nix directory.

6. Remove the files Nix added to your system, except for the store:

   sudo rm -rf /etc/nix /var/root/.nix-profile /var/root/.nix-defexpr /var/root/.nix-channels ~/.nix-profile ~/.nix-defexpr ~/.nix-channels
   

7. Remove the Nix Store volume:

   sudo diskutil apfs deleteVolume /nix
   

   This will remove the Nix Store volume and everything that was added to the store.

   If the output indicates that the command couldn't remove the volume, you should make sure you don't have an unmounted Nix Store volume. Look for a "Nix Store" volume in the output of the following command:

   diskutil list
   

   If you do find a "Nix Store" volume, delete it by running diskutil deleteVolume with the store volume's diskXsY identifier.

Note

After you complete the steps here, you will still have an empty /nix directory. This is an expected sign of a successful uninstall. The empty /nix directory will disappear the next time you reboot.

You do not have to reboot to finish uninstalling Nix. The uninstall is complete. macOS (Catalina+) directly controls root directories, and its read-only root will prevent you from manually deleting the empty /nix mountpoint.

Single User

To remove a single-user installation of Nix, run:

$ rm -rf /nix ~/.nix-channels ~/.nix-defexpr ~/.nix-profile

You might also want to manually remove references to Nix from your ~/.profile.