Future of ReactiveX and Kotlin

Kotlin is a powerful and pragmatic language. JetBrains put in a lot of effort not only to make it effective, but also compatible with existing Java code and libraries. Despite a few rough patches such as SAM lambda inference, they did a phenomenal job making Java and Kotlin work together. However, even with this solid compatibility, many developers become eager to migrate entirely to Kotlin to leverage its functionality. Named parameters, optional parameters, nullable types, extension functions, inline functions, delegates, and other language features make Kotlin attractive for exclusive use. Not to mention, JetBrains has successfully made Kotlin compilable to JavaScript and will soon support LLVM native compilation. Libraries built in pure Kotlin can potentially be compiled to all these platforms. To solidify Kotlin's position even further...