Clojure. It’s built on top of JVM, it’s dynamically typed but it makes so much sense, it’s probably language that makes most sense out of dynamic type system. It really is language for solving problems, if you get past that initial brackets lisp barrier, it is amazing, very efficient and it feels really good to solve problems with it. I don’t know why but it just feels great to use it. Plus it has really nice tools for Emacs. I am learning it and really enjoy it, astonishingly powerful.