We are developing multiplatform compilation capabilities to facilitate sharing code between multiply backends or configurations. A straightforward example is sharing data classes between JVM backend to serialise some JSON, and JavaScript frontend to convert JSON to typed data structures. One more example (less explored) is a game engine like libgdx with API defined in common code and mapped to something specific for each platform. For now we are looking mostly at sharing code between JVM and JS, but in general those could be various JVMs (e.g. Dalvik vs HotSpot), and it would work with future Kotlin Native, etc.
If you are interested in this topic, please share your use cases, requirements, ideas, etc. From time to time we would post questions and discussion topics here, so even if there is no activity for a while, stay tuned.