enum class languages {
  cpp, java, javascript, json, xml, 
  // deprecated
  objective_c, pascal, basic
};

enum class philosophy {
  form_follows_function, test_driven, reuse_code,
  reduce_dependencies, think_functional, model_view_control,
  multi_platform, create_libraries, sustainable_development
};

enum class os {
  linux, windows, nixos, android,
  // deprecated
  ios, macos
};

enum class protocols {
  REST, gRPC, TCP/IP,
  // deprecated
  java_rmi, corba
};

enum class libraries {
  boost, opencv, dlib, guipp, qt, spring-mvc,
  // deprecated
  liant_views, ilog_views, msvc, swing, awt
};

enum class tools {
  git, cmake, doxygen, vscode, qtcreator, 
  visual_studio, idea, eclipse, ant,
  // deprecated
  make
};

enum class hardware {
  basler_camera, matrix_vision_camera, nanotec_motor,
  behringer_control, ccd_camera, stepper_motor,
  rs_232, rs_485, can_bus
};