Kotlin is not much simpler than Scala. It implements some of the Scala features in actually more complex and IMHO less elegant way,(pattern matching, null safety), copies some 1:1 (declaration site variance) and leaves out some of the most powerful ones (implicits, dependent types). I personally don't buy it. I like languages which offer few, but very general and powerful features / abstractions, than languages that concentrate on directly supporting special cases.