Kotlin runs on the JVM and uses the entire Java ecosystem, but adds null safety, coroutines and a much more concise syntax. It has been the preferred language on Android for years and is increasingly used alongside Java in backends.
Spring Boot supports Kotlin as a first-class language, Ktor is the lightweight, coroutine-based framework by JetBrains. Teams that want backend and Android app from one source can even share code between them with Kotlin Multiplatform.
Typical uses
- Backends with Spring Boot or Ktor
- Android apps and shared logic
- Microservices on the JVM
- Modernising existing Java applications
Web frameworks
- Ktor Asynchronous framework by JetBrains
- Spring Boot With full Kotlin support
- http4k Functional HTTP toolkit
- Javalin Minimal web framework
- Micronaut / Quarkus Microservice frameworks with Kotlin support
- Vert.x Reactive toolkit
Android
- Jetpack Compose Declarative Android user interfaces
- Android Jetpack Navigation, Room, WorkManager and more
- Retrofit / OkHttp / Ktor Client HTTP clients
- Hilt Dependency injection on Android
More on Kotlin
A project with Kotlin?
New development, replacement or extending an existing system: tell us briefly what it is about. We will tell you what works in practice.