Atually, for vert.x in particular, it is quite eas...

# coroutines

[elizarov]

Atually, for vert.x in particular, it is quite easy to implement once-for-all helper function as shown here: https://github.com/Kotlin/kotlin-coroutines/blob/master/kotlin-coroutines-informal.md#wrapping-callbacks It has a vert.x example at the end