Clojure - if you're looking for a dynamically typed language with REPL driven development process - it can leverage the huge JVM ecosystem and the concurrency t

Clojure - if you're looking for a dynamically typed language with REPL driven development process - it can leverage the huge JVM ecosystem and the concurrency tools are best in class compared to mainstream languages. Performance often comes down to idiomatic vs optimized - but you can optimize stuff and there's always "drop to Java transparently" card if you hit a wall in some area.