That's right, when a Swift class extends `NSObject...

# random

[jasper]

That's right, when a Swift class extends NSObject or has @objc it will use the ObjC runtime. This includes:
- message based method dispatch in place of static/vtable. Slower, but can be intercepted or forward. Use it to implement proxies, observers, etc
- class and method introspection
"Pure" Swift classes are more like C++ - static/vtable dispatch (therefore no interception), and no introspection/reflection.

And any Kotlin libs for the JVM that use these features won't port to Kotlin/Native.