{
  description = "OOTT - An easy to setup and use network device monitoring service";

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

  outputs = {
    self,
    nixpkgs,
  }: let
    # System types to support.
    supportedSystems = ["x86_64-linux"];

    # Helper function to generate an attrset '{ x86_64-linux = f "x86_64-linux"; ... }'.
    forAllSystems = nixpkgs.lib.genAttrs supportedSystems;

    # Nixpkgs instantiated for supported system types.
    nixpkgsFor = forAllSystems (system: import nixpkgs {inherit system;});

    version = "0.0.1";
    pname = "oott";
  in {
    packages = forAllSystems (system: let
      pkgs = nixpkgsFor.${system};
    in {
      ${pname} = pkgs.rustPlatform.buildRustPackage rec {
        inherit pname;
        inherit version;
        src = ./.;
        cargoLock = {
          lockFile = ./Cargo.lock;
        };

        nativeBuildInputs = [pkgs.pkg-config];
        PKG_CONFIG_PATH = "${pkgs.openssl.dev}/lib/pkgconfig";
      };
    });

    nixosModules = forAllSystems (system: let
      pkgs = nixpkgsFor.${system};
    in
      {
        config,
        lib,
        pkgs,
        ...
      }:
        with lib; let
          cfg = config.services.oott;
        in {
          options.services.oott = {
            enable = mkEnableOption "Enable oott as a service";

            package = mkOption {
              type = types.package;
              default = self.packages.${system}.oott;
              description = "oott package to use";
            };
            networking.interface = mkOption {
              type = types.str;
              description = "Network interface to use for scans";
              default = "eno1";
            };
            log.level = mkOption {
              type = types.str;
              description = "Log level for the oott service";
              default = "info";
            };
          };
          config = mkIf cfg.enable {
            systemd.services.oott = {
              description = "oott - network device scanner";
              wantedBy = ["multi-user.target"];

              serviceConfig = {
                ExecStart = "${cfg.package}/bin/oott ${
                  builtins.toFile "oott.toml"
                  (generators.toTOML {} cfg)
                }";
                ProtectHome = "read-only";
                Restart = "on-failure";
                Type = "exec";
              };
            };
          };
        });
  };
}