This is one reason I never explored it. There has been some research into "gradually typing" dynamic-typed systems, and it gets hairy pretty quick. In any case

This is one reason I never explored it. There has been some research into "gradually typing" dynamic-typed systems, and it gets hairy pretty quick. In any case, I know JRuby's not going to be able to get boxed math as fast as primitive math, and that's ok. We'll just make it easy to use languages that can do fast math, and make method invocation against normal objects as fast as possible to compensate.