> something useful and valuable in job market in the future "Useful" and "valuable in job market" might not overlap too much. The small subset of Groovy used

> something useful and valuable in job market in the future "Useful" and "valuable in job market" might not overlap too much. The small subset of Groovy used in Gradle build files and for quick scripts manipulating Java class files is both useful and valuable, but it's pointless progressing beyond that initial stage. Scala might have peaked in uptake so may not be so valuable, but if you already know Java, it could be useful to learn and practise its functional aspects as a halfway step towards a full funcitonal language like Haskell which is very useful to know.