The author translated Domain Modeling Made Functional by Scott Wlaschin into Korean and rewrote F# examples in TypeScript and Kotlin.
The task involved explaining F# concepts in TypeScript and Kotlin, specifically focusing on effect handling using Arrow in Kotlin.
The author found Kotlin's unique features like extension functions, lambda-based DSLs, and expressive syntax challenging, especially when delving into effect handling with Arrow.
The author previously familiar with monads, had to adapt to using effect handlers in Kotlin and eventually implemented them in Go despite the unfamiliarity with this approach.