[_3sno]

I think one feature of Kotlin that is underestimated is extension functions. Combine them with autocompletion and you've got a great developer experience. Finding the method you need no longer requires a Google, and optimisation pays off massively in terms of productivity by tightening the development loop.

[zaphirplane]

Extension functions are dispatched statically which can be surprising if you can’t tell what is an extension and what isn’t