Not personally but it's happening in a few apps at my current company. In my job I mix Java and Groovy and at home I've mixed Java and Kotlin and it mostly just

Not personally but it's happening in a few apps at my current company. In my job I mix Java and Groovy and at home I've mixed Java and Kotlin and it mostly just works (I don't think you can inherit Java -> other language -> Java because things get compiled in order but that has only been an issue for me once).