[root@cloud-231 ~]# su tempuser
[tempuser@cloud-231 root]$ curl https://nixos.org/nix/install | sh -s -- --daemon
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100  2472  100  2472    0     0   7744      0 --:--:-- --:--:-- --:--:--  7749
downloading Nix 2.0.4 binary tarball for x86_64-linux from 'https://nixos.org/releases/nix/nix-2.0.4/nix-2.0.4-x86_64-linux.tar.bz2' to '/tmp/nix-binary-tarball-unpack.VxpHjrnht5'...
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100 21.0M  100 21.0M    0     0  9210k      0  0:00:02  0:00:02 --:--:-- 9213k
Switching to the Daemon-based Installer
Welcome to the Multi-User Nix Installation

This installation tool will set up your computer with the Nix package
manager. This will happen in a few stages:

1. Make sure your computer doesn't already have Nix. If it does, I
   will show you instructions on how to clean up your old one.

2. Show you what we are going to install and where. Then we will ask
   if you are ready to continue.

3. Create the system users and groups that the Nix daemon uses to run
   builds.

4. Perform the basic installation of the Nix files daemon.

5. Configure your shell to import special Nix Profile files, so you
   can use Nix.

6. Start the Nix daemon.

Would you like to see a more detailed list of what we will do?
No TTY, assuming you would say yes :)

We will:

 - make sure your computer doesn't already have Nix files
   (if it does, I  will tell you how to clean them up.)
 - create local users (see the list above for the users we'll make)
 - create a local group (nixbld)
 - install Nix in to /nix
 - create a configuration file in /etc/nix
 - set up the "default profile" by creating some Nix-related files in
   /root
 - back up /etc/bashrc to /etc/bashrc.backup-before-nix
 - update /etc/bashrc to include some Nix configuration
 - load and start a service (at /etc/systemd/system/nix-daemon.service
   and /etc/systemd/system/nix-daemon.socket) for nix-daemon

Ready to continue?
No TTY, assuming you would say yes :)

---- let's talk about sudo -----------------------------------------------------
This script is going to call sudo a lot. Normally, it would show you
exactly what commands it is running and why. However, the script is
run in a headless fashion, like this:

  $ curl https://nixos.org/nix/install | sh

or maybe in a CI pipeline. Because of that, we're going to skip the
verbose output in the interest of brevity.

If you would like to
see the output, try like this:

  $ curl -o install-nix https://nixos.org/nix/install
  $ sh ./install-nix


---- oh no! --------------------------------------------------------------------
Nix already appears to be installed, and this tool assumes it is
_not_ yet installed.


Uninstalling nix:
1. Delete the files Nix added to your system:

  sudo rm -rf /etc/nix /nix /root/.nix-profile /root/.nix-defexpr /root/.nix-channels /home/tempuser/.nix-profile /home/tempuser/.nix-defexpr /home/tempuser/.nix-channels

and that is it.

We'd love to help if you need it.

If you can, open an issue at https://github.com/nixos/nix/issues

Or feel free to contact the team,
 - on IRC #nixos on irc.freenode.net
 - on twitter @nixos_org