{
  inputs = {
    # nixpkgs.url = "github:nixos/nixpkgs/nixos-23.05";
    nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable";
    nixpkgs-unstable.url = "github:nixos/nixpkgs/nixos-unstable-small";
    nixpkgs-master.url = "github:nixos/nixpkgs/master";

    get-flake.url = "github:ursi/get-flake";

    home-manager.url = "github:nix-community/home-manager/master";
    home-manager.inputs.nixpkgs.follows = "nixpkgs";

    disko.url = "github:nix-community/disko";
    disko.inputs.nixpkgs.follows = "nixpkgs";
    srvos.url = "github:numtide/srvos";
    srvos.inputs.nixpkgs.follows = "nixpkgs";

    bpir3.url = "github:nakato/nixos-bpir3-example";
    bpir3.inputs.nixpkgs.follows = "nixpkgs";

    nixos-nftables-firewall.url = "github:thelegy/nixos-nftables-firewall";
    nixos-nftables-firewall.inputs.nixpkgs.follows = "nixpkgs";
  };

  # outputs = _: {};

  outputs = {
    self,
    get-flake,
    nixpkgs,
    bpir3,
    ...
  } @ attrs: let
    system = "aarch64-linux";
    nodeName = "router0-dmz0";

    mkNixosConfiguration = {extraModules ? [], ...} @ attrs:
      nixpkgs.lib.nixosSystem (
        nixpkgs.lib.attrsets.recursiveUpdate
        attrs
        {
          specialArgs = {
            nodeFlake = self;
            repoFlake = get-flake ../../../..;
            inherit nodeName;
            inherit
              (bpir3.packages.${system})
              armTrustedFirmwareMT7986
              ;
          };

          modules =
            [
              ./configuration.nix

              # flake registry
              {
                nix.registry.nixpkgs.flake = nixpkgs;
              }

              {
                nixpkgs.overlays = [
                  (final: previous: let
                    bpir3Pkgs = previous.callPackage "${bpir3}/pkgs" {};
                  in {
                    inherit
                      (bpir3Pkgs)
                      linuxPackages_bpir3
                      ;
                  })
                ];
              }
            ]
            ++ extraModules;
        }
      );
  in {
    nixosConfigurations = {
      native = mkNixosConfiguration {
        inherit system;
      };

      cross = mkNixosConfiguration {
        extraModules = [
          {
            nixpkgs.buildPlatform.system = "x86_64-linux";
            nixpkgs.hostPlatform.system = system;
          }
        ];
      };
    };
  };
}