Using home-manager during nixos install

[eyeinsky]

is it possible to use home-manager during installing nixos from an usb stick? I.e when I have booted from an usb stick and the to-be-root is mounted to /mnt?

[inigosola]

+1

[kloenk]

I don't understand what you want to achieve. If you just want your config on the shell to install, you can build your own ISO, which includes home-manager.

home-manager needs a directory wich is not auto created at first boot, so you should include an activation Script like This:

{
  system.activationScripts = {
    base-dirs = {
      text = ''
        mkdir -p /nix/var/nix/profiles/per-user/kloenk
      '';
      deps = [ ];
    };
  };
}

[eyeinsky]

@kloenk I'm new to this so bear that in mind, but:

When installing nixos I boot from external media, prepare the disk, then generate the hardware-configuration.nix and configuration.nix into /mnt/etc/nixos/. At this point I clone my private repo, and from the /mnt/etc/nixos/configuration.nix point to a configuration file in that repo, and then run nixos-install. In the linked configuration file I already use home-manager (in addition to defining the OS itself), and although the home-manager works as expected when I'm already inside the newly installed nixos, then it doesn't while I'm outside.

Perhaps using home-manager at install-time isn't supposed to work, I don't really know. With this ticket I'm trying to find out.

[kloenk]

I'm still not sure what you want to do. nixos-install is just supposed to install things, and not to activate anything, so no home-manager is installed yet (not even if you use nixos-enter). If you want to have you home configuration at install time in the external media, you would have to build your own ISO, which can inclued the home-manager module.

You could create a file like this, and execute nix-build to build your own ISO:

let
  nixos = import <nixpkgs/nixos> {
    configuration = { pkgs, lib, ... }: {
      imports = [
        ((fetchTarball
          "https://github.com/rycee/home-manager/archive/master.tar.gz")
          + "/nixos")
        <nixpkgs/nixos/modules/installer/cd-dvd/installation-cd-minimal.nix>
        <nixpkgs/nixos/modules/installer/cd-dvd/channel.nix>
      ];
      systemd.services.sshd.wantedBy = lib.mkForce [ "multi-user.target" ];
      networking.hostName = "kexec";

      users.users.eyeinsky = {
        isNormalUser = true;
        uid = 1000;
        extraGroups = [ "wheel" ];
        shell = pkgs.fish;
        openssh.authorizedKeys.keys = [
          "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIBps9Mp/xZax8/y9fW1Gt73SkskcBux1jDAB8rv0EYUt cardno:000611120054"
        ];
        packages = with pkgs; [
          wget
          nload
          htop
          ripgrep
          git
          gptfdisk
          nix-prefetch-git
          pass
          pass-otp
          gopass
          sl
          neofetch
        ];
      };

      # create dirs for home-manager
      system.activationScripts = {
        base-dirs = {
          text = ''
            mkdir -p /nix/var/nix/profiles/per-user/kloenk
          '';
          deps = [ ];
        };
      };
    };
  };
in nixos.config.system.build.isoImage

[eyeinsky]

What I would like to do is have home-manager create the home folder for me. Perhaps this is out of scope, etc. but in general that's what I would like to do.

If I do nixos-rebuild from inside an installed nixos then the situation is similar: the system config rooted at /etc/nixos/configuration.nix builds both the system and the home folder for me. So if I do nixos-install with the same set of configuration files then I thought that it maybe will do the same thing.

Would this be good new feature to be added?

Edit:

I use home-manager as a nixos module like this:

{ config, lib, pkgs, ... }:
let
  home-manager = builtins.fetchGit {
    url = "https://github.com/rycee/home-manager.git";
    rev = "8d663335eb7b5032f637d8b719416ae4f2c1f612";
    ref = "release-19.09";
  };
in
{
  imports = [ (import "${home-manager}/nixos") ];
  # system code here

  home-manager.users.someUser = {
    # user code here
  }
}

I think home-manager is fetched while nixos-install runs, but as you say, it doesn't build the home folder nor activate it.

[kloenk]

I think this is a duplicate of #948. Home manager populates you home manager. But only after it is ready to install things. The home directory itself is created by nixos, if you set users.users.name.isNormalsUser = true.

nixos-install and nixos-rebuild do very similar things. And if you run nixos-rebuild boot, your homemanager also doesn't get started.

[austinbutler]

I'm still not clear as to whether having home-manager enabled as a module in your configuration.nix during initial installation of NixOS is supported or not.

Meaning in a brand new install, still in the live ISO, having <home-manager/nixos> in /mnt/etc/nixos/configuration.nix, then running nixos-install. Should that work? Or do we just stick basically to the automatically generated configuration.nix, run nixos-install, reboot, then from the installed system add home manager as a module?

[eyeinsky]

@austinbutler strictly speaking: no. But I never tried what @kloenk proposed above: to create the profile folder manually (mkdir -p /nix/var/nix/profiles/per-user/$your_username). If you are in the midst of an install and have time to try, do!

[austinbutler]

Is the idea creating /nix/var/nix/profiles/per-user/$your_username on the live USB? In my case that already exists. Well at least for user nixos from the live USB. I don't know if it's because I created my own installer ISO that uses home-manager itself.

Where I am at right now is home-manager works for configuring the live ISO itself, but I get a strange "file or folder not found" error when trying to install NixOS from the booted live ISO USB. The file not found is a VS Code extension, and it references /nix/store (not sure if that's a problem and it should be referencing /mnt/nix/store), however the folder does exist and has the extension in it.

[berbiche]

If Home Manager is installed side-by-side with NixOS, I think you would need to chroot /mnt for the install script / flake configuration to work correctly.
If used as a NixOS module, it should work out of the box I think?

[austinbutler]

I'm using it as a module in both the live ISO and the installed system. It kept complaining about the same VS Code extension (even though the same config works fine on my other systems that share the same config), so for now I've commented out the VS Code home-manager config and am re-running the install. It's still running and hasn't died yet...

[austinbutler]

Well it did work. I guess the file not found error was maybe a red herring. After installation I rebooted, logged in as root, then checked and the normal user folder existed and has my tmux.conf in it as expected. I did not have to use the creating a profile file workaround as suggested earlier, which I was assuming was the case since it seemed a fix had been merged a while back.

To sum up, I was able to make a live ISO that configured some things for the default nixos user and I was also able to install NixOS with home manager as a module.

Does that mean this issue can be closed?

[eyeinsky]

@austinbutler Just to sum up/clarify, you were installing NixOS, had booted from a USD stick, had a configuration.nix ready with a line imports = [ <home-manager/nixos> ];, also had a configuration for a user in there, and when you ran nixos-install then after reboot you had the user folder correctly prepared? If so then yes I think the issue can be closed. (Anyone can always reopen it if there are hiccups)

[austinbutler]

For the ISO I have this in configuration.nix:

{
 imports = [
    ((fetchTarball
      "https://github.com/rycee/home-manager/archive/master.tar.gz") + "/nixos")
  ];
}

Then the normal imports = [ <home-manager/nixos> ]; for the configuration.nix for the target machine installation.