2 years back we had huge debate to choose between Kotlin or Java. While Java folks thought it was immature to even discuss anything other than Java, we ended up

2 years back we had huge debate to choose between Kotlin or Java. While Java folks thought it was immature to even discuss anything other than Java, we ended up adopting Kotlin company wide. Looking back at it we don't regret the decision even single bit! We are using Kotlin and Coroutines to run extremely heavy services (almost 1K req/sec per pod, with complex logic, few hundred threads, 6GB RAM and 2 CPU cores). People concerned with Project Loom, should remember it's backwards compatible & upgrade path can be done multiple ways. I would highly recommend Kotlin for backend services, you won't have to code review IDE vomit, depend on annotations, or live with callback hell (project reactor, rx-java).