The Kotlin language is excellent, but I have to emphasise a major drawback:
The standard distribution comes with a very weak REPL (Read Evaluate Print Loop), that does not
support even code completion. Other competitive languages as Java (with JShell) and Scala come
with more usable and much better REPLs, and I consider the REPL very important for the programmer.
There is a much better Kotlin REPL, with strong features:
but why is not integrated with the standard Kotlin installation?
I think it is urgent to bring to Kotlin users a much better REPL as soon as possible.