Thanks. I'll take a look. Didn't mean to overlook Java, I'm just less familiar with that environment. I've dabbled with some JVM languages and could also see Kotlin being a very nice option for such a framework. Though, to be fair, I know Java has come a long way in terms of expressivity, syntactic sugar, etc. (better performance is a given).

You can use such frameworks from kotlin too, they have full support.