RubyCocoa - Disadvantages

Disadvantages

  • Ignoring the speed of the Ruby interpreter, RubyCocoa applications will always be slower than Objective-C/Cocoa applications due to the added overhead of object conversion.
  • Because Ruby isn't thread-safe, it isn't possible to dispatch multiple native threads to execute RubyCocoa code. Ruby's emulated threads, however, can be used.

Read more about this topic:  RubyCocoa