I disagree that ObjC or Swift would result in a better experience by themselves, however I assume you meant to say Cocoa/AppKit and SwiftUI, in which case I wou

I disagree that ObjC or Swift would result in a better experience by themselves, however I assume you meant to say Cocoa/AppKit and SwiftUI, in which case I would agree. Note that while SwiftUI benefits greatly from being written in Swift, you could write Cocoa/AppKit quite easily in many languages since it's fairly easy to bind ObjC. There's even Rust bindings https://docs.rs/cacao/latest/cacao/ https://docs.rs/cacao/latest/cacao/ For SwiftUI, I'm sure someone has written an adapter in other languages but there's so much under the hood magic that SwiftUI does that's tied into the language runtimes, that I think it would be truly herculean to do something in another language.