clojure (Dynamic programming language for the JVM)

Clojure is a dynamic, general-purpose programming language that targets
the Java Virtual Machine. It is designed to be a general-purpose
language, combining the approachability and interactive development of
a scripting language with efficient and robust infrastructure for
multithreaded programming. Clojure is a compiled language – Every
feature supported by Clojure is supported at runtime. Clojure provides
easy access to the Java frameworks, with optional type hints and type
inference, to ensure that calls to Java can avoid reflection.

Clojure is a dialect of Lisp, and shares with Lisp the code-as-data
philosophy and a powerful macro system. CLojure is predominantly a
functional programming language, and features a rich set of immutable,
persistent data structures. When mutable state is needed, Clojure
offers a software transactional memory system that ensures clean,
correct, multithreaded designs.