Kotlin is a new language being developed by JetBrains. http://confluence.jetbrains.net/display/Kotlin/Welcome Like Scala, it is trying to be a better Java. It has first-class functions, closures, type-inference, and other goodies. Unlike Scala, but like F#, it is developed by a company. As a result, it will have good IDE support right from the beginning. (Who likes to deal with IDE plugins?) I am going to keep an eye on this new development. If the compiler can generate fast and efficient code it may have a bright future in trading.