I like Typescript, it makes Javascript enjoyable to me. I use PEP 484 heavily in Python which help as well. I have no issues with Kotlin on the typing side of

I like Typescript, it makes Javascript enjoyable to me. I use PEP 484 heavily in Python which help as well. I have no issues with Kotlin on the typing side of the house, val/var works well to infer types. I have issues with Kotlin in other areas (Jetbrains only ecosystem, threading (comes back to JS), compilation speed, personal stubbornness). I don't have any experience with Swift. Edit: A note on val/var w/ Kotlin, Intellij/Android Studio makes it easier to determine what the type of the variable is without having to dig for anything, looking upstream.