It is possible but contorting Xcode to building it might be more trouble than it is worth. The original KotlinConf iOS app was all native except for some placeholder classes that were used to work with Interface Builder. One could build out the majority of an app in a framework target and then just have a small shim written in ObjC/Swift to load the first view controller from that framework. Flutter does something similar. I personally try to keep my Kotlin code from interacting with the cocoa apis when I can because it doesn't feel as natural as it does when writing Swift or ObjC and so I limit my Kotlin usage to shared logic.