More libraries
Libraries that complement the Arrow ecosystem
SuspendApp
Reason about resource-safety in the same way you reason about Structured Concurrency
Quiver
Additional functional programming idioms over and above what is available from Arrow.
kotlinx-serialization-jsonpath
DSL for accessing and modifying deeply nested JSON for KotlinX Serialization with Arrow Optics
Hoplite
Boilerplate-free Kotlin config library for loading configuration files as data classes
Tribune
Toolset for creating simple parsers from raw input types, to properly validated parsed types

Parsus
Parser-combinators with Kotlin Coroutines
KopyKat
Little utilities for more pleasant immutable data in Kotlin
Inikio
Better initial-style DSLs in Kotlin
Even more libraries?
We'd love to hear about other library which complements the Arrow libraries and should be featured here!