Kotlin <-> Java interop is a totally optional topic you could have skipped over, telling you as a Kotlin developer (who recently had to switch to .NET because Ukrainian job market is fucked up). besides, Java itself isn't that hard if it's Java 17 or newer, and it's rather good if it's Java 25 or newer

> Kotlin <-> Java interop is a totally optional topic you could have skipped over

This is the same place F# has been stuck in. It’s a great language on its own, but you can’t just use F#. Every F# must also do C# interop. It’s too 100% optional in theory, but never in practice. The best CLR/JVM libraries for anything are Java/C# ones. You need to interop with them to develop practical Kotlin/F# applications. You can limit yourself to the Kotlin/F# ones, but then you’re artificially limiting yourself to experimental libraries at best. You will find yourself needing a charting library, a DNS library, an SMTP library, an AWS SDK or a rabbitmq SDK. The best ones are gonna be Java/C#. Yes, you can always find a random GitHub repo for a “Kotlin-native X”, but the Java X library is a thousand times more mature, stable, performant, feature rich, etc. Same problem with F#. And the “glue” code is so “straight forward”, why would any one bother?