> Scala is the most expressive and powerful language on the JVM, hands down. So I'd agree with that statement... > do yourself a favor and use Scala ...but n

> Scala is the most expressive and powerful language on the JVM, hands down. So I'd agree with that statement... > do yourself a favor and use Scala ...but not that one. I've found that Scala gets too expressive, much the same way that writing production code in Common Lisp or Haskell can be slower than just writing it in Python. It offers incredibly powerful abstraction capabilities that can often dramatically reduce the amount of code you write; but at some point you end up spending more time hunting for the perfect abstraction than actually writing the code. The ideal programming language (for productivity at least, not necessarily for fun or erudition) is one that melts into the background when you program so that you can focus on the problem domain rather than the program. That's the main appeal of languages like Go, Java, and Python: they offer just enough power to write the program, but not so much that you can write the program in a dramatically better way and end up tempted to try and find that way. Kotlin embraces the "it's just a better Java" approach: it's a minor re-skinning of the concepts in Java, and to the extent that it introduces new language features (like closures, lambdas, properties, data classes, anonymous objects, type inference, and immutability), they're all concepts that skilled Java programmers would be immediately familiar with but would otherwise have to write lots of boilerplate for. The Java interop story is also better with Kotlin, because Scala introduces abstractions for which there are no obvious Java equivalents, and hence there's an impedance mismatch when you try to envision how your Java libraries might fit into your Scala program. Kotlin's designers took care to make sure that there's an easy, intuitive mapping between Kotlin concepts and Java ones, usually one that had already been enshrined in existing Java conventions (eg. JavaBeans work nicely with properties, functional objects with lambdas), so most Java libraries just work in an obvious way. Basically they intentionally made it dumber so you don't have to think about as much, which is a win for everyday programming.