Scala.js - Build robust front-end web applications in Scala with Scala.js
Python - Python is a clear and powerful object-oriented programming language, comparable to Perl, Ruby, Scheme, or Java.
Imba - Take a whole lot of Ruby, a pinch of Python and some React, get Imba
Java - A concurrent, class-based, object-oriented, language specifically designed to have as few implementation dependencies as possible
PureScript - PureScript is a small strongly typed programming language that compiles to JavaScript.
Rust - A safe, concurrent, practical language