# Uninstalling Nix

## Single User

If you have a [single-user installation](./installing-binary.md#single-user-installation) of Nix, uninstall it by running:

```console
$ rm -rf /nix
```

## Multi User

Removing a [multi-user installation](./installing-binary.md#multi-user-installation) of Nix is more involved, and depends on the operating system.

### Linux

If you are on Linux with systemd:

1. Remove the Nix daemon service:

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

Remove files created by Nix:

```console
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:

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

   ```bash
   # 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
   ```

   If these files haven't been altered since installing Nix you can simply put
   the backups back in place:

   ```console
   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
   ```

   This will stop shells from sourcing the file and bringing everything you
   installed using Nix in scope.

2. Stop and remove the Nix daemon services:

   ```console
   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:

   ```console
   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`. 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, `sudo rm /etc/synthetic.conf`.
   This will prevent the creation of the empty `/nix` directory to provide a
   mountpoint for the Nix Store volume.

6. Remove the files Nix added to your system:

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

   This gets rid of any data Nix may have created except for the store which is
   removed next.

7. Remove the Nix Store volume:

   ```console
   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:

   ```console
   diskutil list
   ```

   If you _do_ see a "Nix Store" volume, delete it by re-running the diskutil
   deleteVolume command, but replace `/nix` 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.