{
  description = "Homelab NixOS configuration";

  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs/nixos-26.05";
    disko = {
      url = "github:nix-community/disko";
      inputs.nixpkgs.follows = "nixpkgs";
    };
    sops-nix = {
      url = "github:Mic92/sops-nix";
      inputs.nixpkgs.follows = "nixpkgs";
    };
  };

  outputs = { self, nixpkgs, disko, sops-nix, ... }@inputs:
    let
      system = "x86_64-linux";
    in
    {
      nixosConfigurations = {
        # Real host — install on the ZimaBlade.
        # disko owns the OS-disk partitioning + filesystems (see disk-config.nix).
        jupiter = nixpkgs.lib.nixosSystem {
          inherit system;
          specialArgs = { inherit inputs; };
          modules = [
            disko.nixosModules.disko
            sops-nix.nixosModules.sops
            ./jupiter/configuration.nix
          ];
        };

        # VirtualBox test image. Build the OVA with:
        #   nix build .#nixosConfigurations.jupiter-vbox.config.system.build.virtualBoxOVA
        # NOTE: no disko here — the virtualbox-image module supplies the disk.
        jupiter-vbox = nixpkgs.lib.nixosSystem {
          inherit system;
          specialArgs = { inherit inputs; };
          modules = [ ./jupiter/vm.nix ];
        };
      };
    };
}