{
  # lib,
  # config,
  # pkgs,
  ...
}:
{
  _class = "clan.service";
  manifest.name = "clan-core/syncthing";
  manifest.description = "A secure, file synchronization app for devices over networks";

  roles.introducer = {
    interface =
      { lib, ... }:
      {
        options = {

          id = lib.mkOption {
            description = ''
              The ID of the machine.
              It is generated automatically by default.
            '';
            type = lib.types.nullOr lib.types.str;
            example = "BABNJY4-G2ICDLF-QQEG7DD-N3OBNGF-BCCOFK6-MV3K7QJ-2WUZHXS-7DTW4AS";
            # default = config.clan.core.vars.generators.syncthing.files."id".value;
            defaultText = "config.clan.core.vars.generators.syncthing.files.\"id\".value";
          };
          introducer = lib.mkOption {
            description = ''
              The introducer for the machine.
            '';
            type = lib.types.nullOr lib.types.str;
            default = null;
          };
          autoAcceptDevices = lib.mkOption {
            description = ''
              Auto accept incoming device requests.
              Should only be used on the introducer.
            '';
            type = lib.types.bool;
            default = false;
          };
          autoShares = lib.mkOption {
            description = ''
              Auto share the following Folders by their ID's with introduced devices.
              Should only be used on the introducer.
            '';
            type = lib.types.listOf lib.types.str;
            default = [ ];
            example = [
              "folder1"
              "folder2"
            ];
          };

        };
      };

    perInstance =
      {

        # instanceName,
        roles,
        settings,
        ...
      }:

      {
        nixosModule =
          {
            ...
          }:
          {
            _module.args = { inherit settings roles; };
            imports = [
              ./shared.nix
            ];
          };
      };
  };

  roles.peer = {
    interface =
      { lib, ... }:
      {
        options = {

          id = lib.mkOption {
            description = ''
              The ID of the machine.
              It is generated automatically by default.
            '';
            type = lib.types.nullOr lib.types.str;
            example = "BABNJY4-G2ICDLF-QQEG7DD-N3OBNGF-BCCOFK6-MV3K7QJ-2WUZHXS-7DTW4AS";
            # default = config.clan.core.vars.generators.syncthing.files."id".value;
            defaultText = "config.clan.core.vars.generators.syncthing.files.\"id\".value";
          };
          introducer = lib.mkOption {
            description = ''
              The introducer for the machine.
            '';
            type = lib.types.nullOr lib.types.str;
            default = null;
          };
          autoAcceptDevices = lib.mkOption {
            description = ''
              Auto accept incoming device requests.
              Should only be used on the introducer.
            '';
            type = lib.types.bool;
            default = false;
          };
          autoShares = lib.mkOption {
            description = ''
              Auto share the following Folders by their ID's with introduced devices.
              Should only be used on the introducer.
            '';
            type = lib.types.listOf lib.types.str;
            default = [ ];
            example = [
              "folder1"
              "folder2"
            ];
          };

        };
      };

    perInstance =
      {

        # instanceName,
        roles,
        settings,
        ...
      }:

      {
        nixosModule =
          {
            ...
          }:

          {
            _module.args = { inherit settings roles; };
            imports = [
              ./shared.nix
            ];

            # clan.syncthing.introducer = lib.strings.removeSuffix "\n" (
            #   if builtins.pathExists introducerId then
            #     builtins.readFile introducerId
            #   else
            #     throw "${introducerId} does not exists. Please run `clan vars generate ${introducer}` to generate the introducer device id"
            # );
          };
      };
  };

}