Nix VM qcow2

nixos-image-qcow2.nix

{ config, lib, pkgs, ... }:

{
  imports =
    [ 
      <nixpkgs/nixos/modules/installer/cd-dvd/channel.nix>
    ];

  system.build.qcow2 = import <nixpkgs/nixos/lib/make-disk-image.nix> {
    pkgs = import <nixpkgs> { inherit (pkgs) system; }; # ensure we use the regular qemu-kvm package
    diskSize = 8192;
    format = "qcow2";

    configFile = pkgs.writeText "configuration.nix"
      ''
        { pkgs, lib, ... }:

        {                           
          imports = [
            <nixpkgs/nixos/modules/profiles/qemu-guest.nix>
          ];                    
                                         
          config = {                                                      
            fileSystems."/" = {                                           
              device = "/dev/disk/by-label/nixos";
              fsType = "ext4";
              autoResize = true;                                          
            };
                                         
            boot.growPartition = true;
            boot.kernelParams = [ "console=ttyS0" ];                      
            boot.loader.grub.device = "/dev/sda";
            boot.loader.timeout = 0;

            security.sudo.enable = false;

            users.extraUsers.root.password = "";
          };
        }
      '';
  };
}