I find it a bit of a dodge when a dynamic language has to go to static types for performance. That's not to say I haven't wanted to have that dodge available to JRuby users, but being unable (or unwilling) to unilaterally add optional static types to Ruby, we've been forced to find more creative options. We'll probably never approach Java's raw primitive math performance, but I think we can easily match Java's speed (and in some cases, already do) at manipulating objects.
It also appears that the push toward more static typing in Groovy may come at the cost of dynamicity...or at least incompatible changes in Groovy's dynamic features. Perhaps it's the best move for them, though; they've always pushed Groovy's ability to run (and enhance) plain old Java code, but performance was considerably worse than Java.
It's unfortunate that other JVM dynamic languages did not start exploring invokedynamic sooner. It has been a complete game-changer for JRuby.
It also appears that the push toward more static typing in Groovy may come at the cost of dynamicity...or at least incompatible changes in Groovy's dynamic features. Perhaps it's the best move for them, though; they've always pushed Groovy's ability to run (and enhance) plain old Java code, but performance was considerably worse than Java.
It's unfortunate that other JVM dynamic languages did not start exploring invokedynamic sooner. It has been a complete game-changer for JRuby.