{
  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs/nixos-23.11";
    nixos-generators = {
      url = "github:nix-community/nixos-generators";
      inputs.nixpkgs.follows = "nixpkgs";
    };
    xc = {
      url = "github:joerdav/xc";
      inputs.nixpkgs.follows = "nixpkgs";
    };
  };

  outputs = { nixpkgs, nixos-generators, xc, ... }:
    let
      pkgsForSystem = system: import nixpkgs {
        inherit system;
        overlays = [
          (final: prev: { xc = xc.packages.${system}.xc; })
        ];
      };
      allVMs = [ "x86_64-linux" "aarch64-linux" ];
      forAllVMs = f: nixpkgs.lib.genAttrs allVMs (system: f {
        inherit system;
        pkgs = pkgsForSystem system;
      });
    in
    {
      packages = forAllVMs ({ system, pkgs }: {
        vm = nixos-generators.nixosGenerate {
          format = "proxmox";
          system = system;

          specialArgs = {
            pkgs = pkgs;
            #diskSize = "8G";
          };

          modules = [
            # Pin nixpkgs to the flake input, so that the packages installed
            # come from the flake inputs.nixpkgs.url.
            ({ ... }: { nix.registry.nixpkgs.flake = nixpkgs; })
            # Apply the rest of the config.
            ./configuration.nix
          ];
        };
      });
    };
}