I moved from Java to Scala this year and I am loving it. What started as a rather basic understanding of FP (from a Haskell course in Uni) has come along leaps and bounds. I now understand what people are talking about when they go into Monads and Applicative Functors, etc. It's brilliant. I wasn't sure on it when I started but FP is something I have really come to love.

I've also played with Go, although while I like some of it I am still not convinced.

Another thing I have started using and really like is DDD and the onion architecture pattern. Its produced some of the nicest code I have seen and has helped make the code base super maintainable, adaptable and clean. Very cool.