[thu2111]

Kotlin does expose JVM specific stuff though. Like the entire class library. You have to specifically opt in to the multiplatform subset to avoid that. It's not like they whitelist APIs. The only time they need to do anything to add new Java features is when the bytecode patterns change.

[pjmlp]

Yeah and then funny things happen when one tries to use libraries written in Java with Kotlin ones together.

https://dev.to/martinhaeusler/why-i-stopped-using-coroutines...

https://dev.to/domnikl/kotlin-coroutines-and-javafx-threads-...

https://blog.danlew.net/2020/01/28/coroutines-and-java-synch...