Chiming in because the two extant comments are dismissive of Scala. I use Scala every day, our current application is written 100% in Scala. We write functiona

Chiming in because the two extant comments are dismissive of Scala. I use Scala every day, our current application is written 100% in Scala. We write functional code, but we are not religious about "purely functional" code. My understanding is that, currently, writing Kotlin means you are almost certainly writing Android apps. If a company chose Kotlin over Scala for a backend/distributed application, I would be astonished. Maybe that is my bias, but Scala is proven and continuing to grow in the distributed space (Akka, ZIO, etc). Regarding scala being "too cryptic". I felt the same way about Django when I first learned it -- now everyone thinks Django is a breeze. I had the luxury of learning Scala on-the-job, and had great mentors who saw the power of the language and helped me realize it too. Scala can be "fancy", but it can also be simple and elegant, if you learn it slowly. Frankly, I think my biggest issue with Scala is that I live in North America, and the really interesting products built in Scala seem to be made by European teams.