{
  description = "gatekeeper using uv2nix"; ##python packaging on nix is so ass :(

  inputs = {
    nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable";

    pyproject-nix = {
      url = "github:pyproject-nix/pyproject.nix";
      inputs.nixpkgs.follows = "nixpkgs";
    };

    uv2nix = {
      url = "github:pyproject-nix/uv2nix";
      inputs.pyproject-nix.follows = "pyproject-nix";
      inputs.nixpkgs.follows = "nixpkgs";
    };

    pyproject-build-systems = {
      url = "github:pyproject-nix/build-system-pkgs";
      inputs.pyproject-nix.follows = "pyproject-nix";
      inputs.uv2nix.follows = "uv2nix";
      inputs.nixpkgs.follows = "nixpkgs";
    };
    nixos-hardware = {
      url = "github:NixOS/nixos-hardware/master";
      inputs.nixpkgs.follows = "nixpkgs";
    };
    nixos-raspberrypi = {
      url = "github:nvmd/nixos-raspberrypi/main";
      inputs.nixpkgs.follows = "nixpkgs";
    };

  };

  outputs =
    {
      nixpkgs,
      pyproject-nix,
      uv2nix,
      pyproject-build-systems,
      nixos-hardware,
      ...
    }:
    let
      inherit (nixpkgs) lib;
      forAllSystems = lib.genAttrs lib.systems.flakeExposed;

      workspace = uv2nix.lib.workspace.loadWorkspace { workspaceRoot = ./.; };

      overlay = workspace.mkPyprojectOverlay {
        sourcePreference = "wheel";
      };

      editableOverlay = workspace.mkEditablePyprojectOverlay {
        root = "$REPO_ROOT";
      };

      pythonSets = forAllSystems (
        system:
        let
          pkgs = nixpkgs.legacyPackages.${system};
          python = pkgs.python3;
        in
        (pkgs.callPackage pyproject-nix.build.packages {
          inherit python;
        }).overrideScope
          (
            lib.composeManyExtensions [
              pyproject-build-systems.overlays.wheel
              overlay
              (final: prev: {
                pyscard = prev.pyscard.overrideAttrs (old: {
                  nativeBuildInputs = (old.nativeBuildInputs or []) ++ [ pkgs.swig pkgs.pkg-config];
                  buildInputs = (old.buildInputs or []) ++ [ pkgs.pcsclite.dev ];
                  NIX_CFLAGS_COMPILE = "-I${pkgs.pcsclite.dev}/include/PCSC";
                });
              })
            ]
          )
      );

    in
    {
      devShells = forAllSystems (
        system:
        let
          pkgs = nixpkgs.legacyPackages.${system};
          pythonSet = pythonSets.${system}.overrideScope editableOverlay;
          virtualenv = pythonSet.mkVirtualEnv "gatekeeper" workspace.deps.all;
        in
        {
          default = pkgs.mkShell {
            packages = [
              virtualenv
              pkgs.uv
              pkgs.pcsclite
              pkgs.pcsclite.dev
              pkgs.swig
              pkgs.pkg-config
            ];
            env = {
              UV_NO_SYNC = "1";
              UV_PYTHON = pythonSet.python.interpreter;
              UV_PYTHON_DOWNLOADS = "never";
              LD_LIBRARY_PATH = "${lib.getLib pkgs.pcsclite}/lib";
            };
            shellHook = ''
              unset PYTHONPATH
              export REPO_ROOT=$(git rev-parse --show-toplevel)
            '';
          };
        }
      );

      packages = forAllSystems (system: {
        default = pythonSets.${system}.mkVirtualEnv "gatekeeper" workspace.deps.default;
      });


      nixosConfigurations = {
        gatekeeper-rpi = nixpkgs.lib.nixosSystem {
          system = "aarch64-linux";
          specialArgs = {
            inherit workspace overlay;
          };
          modules = [
            "${nixpkgs}/nixos/modules/profiles/headless.nix"
            "${nixpkgs}/nixos/modules/profiles/minimal.nix"
            "${nixpkgs}/nixos/modules/installer/sd-card/sd-image-aarch64.nix"
            nixos-hardware.nixosModules.raspberry-pi-3

            ({ pkgs, ... }: {
              nix.nixPath = [
                "nixpkgs=${pkgs.path}"
              ];

              nix.settings = {
                trusted-users = [ "root" "@wheel" ];
                experimental-features = [ "nix-command" "flakes" ];
                auto-optimise-store = true;
              };
            })

            ({ config, pkgs, packages, ...}:
            let
              gatekeeper-app = pkgs.python3Packages.buildPythonPackage {
                pname = "gatekeeper-app";
                version = "0.0.1";
                propagatedBuildInputs = [packages.gatekeeper];
                src = ./app;
                format = "pyproject";
              };
            in 
            {
              boot.loader.grub.enable = false;
              boot.loader.generic-extlinux-compatible.enable = true;
              boot.kernelPackages = pkgs.linuxPackages;
              boot.tmp.cleanOnBoot = true;
              hardware.enableRedistributableFirmware = true;
              networking.hostName = "gatekeeper-rpi";

              #minimal
              documentation.man.enable = false;
              xdg.icons.enable  = false;
              xdg.mime.enable   = false;
              xdg.sounds.enable = false;
              
              users.users.root.openssh.authorizedKeys.keys = ["ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAICKaEcGaSKU0xC5qCwzj2oCLLG4PYjWHZ7/CXHw4urVk atlan@nixos"];
              users.groups = { gatekeeper = {}; };
              users.users.admin = {
                isNormalUser = true;
                extraGroups = [ "wheel" "networkmanager" "gatekeeper" ];
              };
              users.users.gatekeeper = {
                isNormalUser = true;
                extraGroups = ["gatekeeper"];
              };

              services.openssh = {
                enable = true;
                ports = [ 22 ];
                settings = {
                  PasswordAuthentication = false;
                };
              };
              

              environment.systemPackages = with pkgs; [
                git
                htop
                pcsclite
                gatekeeper-app
              ];
              environment.etc."gatekeeper-env".source = 
                  pythonSets.aarch64-linux.mkVirtualEnv "gatekeeper" workspace.deps.default;
              services.pcscd.enable = true;

              systemd.services.gatekeeper = {
                enable = true;
                description = "Gatekeeper service";
                after = [ "network.target" "pcscd.service"];
                wantedBy = [ "multi-user.target" ];

                environment = {
                  LD_LIBRARY_PATH = "${lib.getLib pkgs.pcsclite}/lib";
                  PYTHONPATH = "/etc/gatekeeper-env/lib/python3.x/site-packages";
                };

                serviceConfig = {
                  Type = "simple";
                  User = "gatekeeper";
                  Group = "gatekeeper";
                  WorkingDirectory = "/var/lib/gatekeeper";
                  ExecStart = "${pythonSets.aarch64-linux.mkVirtualEnv "gatekeeper" workspace.deps.default}/bin/python -m uvicorn main:app --host 0.0.0.0 --port 8000";
                  Restart = "always";
                  RestartSec = "10";
                };

                # Create working directory and log directory
                preStart = ''
                  mkdir -p /var/lib/gatekeeper
                  mkdir -p /var/log/gatekeeper
                  chown -R gatekeeper:gatekeeper /var/lib/gatekeeper
                  chown -R gatekeeper:gatekeeper /var/log/gatekeeper
                '';
              };
              networking.firewall.allowedTCPPorts = [ 8000 ];
              
              time.timeZone = "Europe/Berlin";
              system.stateVersion = "25.11";
            })
          ];
        };  
      };
    };
}