{
  description = "A very basic flake";
  nixConfig = {
    extra-substituters = [
      "https://nix-community.cachix.org"
    ];
    extra-trusted-public-keys = [
      "nix-community.cachix.org-1:mB9FSh9qf2dCimDSUo8Zy7bkq5CX+/rkCWyvRCYg3Fs="
    ];
  };

  inputs = {
    nixpkgs.url = "github:nixos/nixpkgs/nixos-25.05";
    authentik = {
      url = "github:MarcelCoding/authentik-nix";
    };
    mailserver = {
      url = "git+https://gitlab.com/simple-nixos-mailserver/nixos-mailserver?ref=nixos-25.05";
      inputs = {
        nixpkgs.follows = "nixpkgs";
        nixpkgs-25_05.follows = "nixpkgs";
      };
    };
    # mailserver.url = "gitlab:simple-nixos-mailserver/nixos-mailserver/nixos-24.11";
    disko = {
      url = "github:nix-community/disko";
      inputs.nixpkgs.follows = "nixpkgs";
    };
  };

  outputs =
    {
      self,
      nixpkgs,
      authentik,
      mailserver,
      disko,
    }:
    {
      formatter.x86_64-linux = nixpkgs.legacyPackages.x86_64-linux.nixfmt-rfc-style;

      nixosConfigurations = {
        authentik = nixpkgs.lib.nixosSystem {
          system = "x86_64-linux";
          modules = [
            ./configuration.nix
            ./hetzner-disk.nix
            disko.nixosModules.disko
            authentik.nixosModules.default
            mailserver.nixosModules.mailserver
          ];
        };
      };
    };
}