At this point this would prolly be my advice as well.

From React/TS, to Kotlin, to PG, to the JOOQ shout out.

I hoped a strongly(ish) language that spans from BE to FE, like ReasonML, would be ready by now, but it isn't.

Kotlin to JS is not there I'm afraid:

https://kotlinlang.org/docs/tutorials/javascript/kotlin-to-j...