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Ktor 3.4.0 Is Now Available!

January 23, 2026

Ktor 3.4.0 Is Now Available!

Ktor 3.4.0 improves stability and addresses outstanding issues. Highlights include OpenAPI generation, Ztsd support for the compression plugin, duplex streaming for OkHttp, Structured concurrency integrations for the HTTP request lifecycle, and much more. For a detailed list of all the changes, check out the What’s new page. Stability and performance With its focus on stability […]

Exposed 1.0 Is Now Available

January 23, 2026

Exposed 1.0 Is Now Available

This is the first major release of Exposed – a huge milestone for both the project and the Exposed team! This release brings many new exciting features, the most requested being R2DBC support, as well as performance enhancements and bug fixes. Exposed 1.0 also introduces a stable API that guarantees no breaking changes until the […]

How to Avoid Common Pitfalls With JPA and Kotlin

January 20, 2026

How to Avoid Common Pitfalls With JPA and Kotlin

This post was written together with Thorben Janssen, who has more than 20 years of experience with JPA and Hibernate and is the author of “Hibernate Tips: More than 70 Solutions to Common Hibernate Problems” and the JPA newsletter. Kotlin and Jakarta Persistence (also known as JPA) are a popular combination for server-side development. Kotlin […]

Update your Kotlin projects for Android Gradle Plugin 9.0

January 16, 2026

Update your Kotlin projects for Android Gradle Plugin 9.0

Android Gradle plugin 9.0 is now available, and it includes two major changes that will affect existing Kotlin projects: This post provides some details about these changes and points you to the resources that you’ll need to update your existing projects. You’ll also need to update tools and plugins that depend on AGP to their […]

Kotlin blog
Why Kotlin?
Code examples
fun main() {
    val name = "stranger"        // Declare your first variable
    println("Hi, $name!")        // ...and use it!
    print("Current count:")
    for (i in 0..10) {           // Loop over a range from 0 to 10
        print(" $i")
    }
}
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Kotlin in action

McDonald's
McDonald's leverages Kotlin Multiplatform (KMP) for their global mobile app, enabling them to build a codebase that can be shared across platforms, removing the need for codebase redundancies.Kotlin Multiplatform
AWS
AWS opted for Kotlin over Java for Amazon Quantum Ledger Database (QLDB) thanks to its expressiveness and structured concurrency. They rewrote QLDB in Kotlin, enhancing the user experience, benefiting from its development workflow, and adopting it fully for server-side development.Server-side
Philips
Philips utilizes Kotlin Multiplatform in its HealthSuite digital platform mobile SDK. With KMP, they accelerated the implementation of new features and fostered increased collaboration between Android and iOS developers.Kotlin Multiplatform
Adobe
Adobe Experience Platform chose Kotlin for server-side development because of its concise syntax, async capabilities, and interoperability with Java. This shift boosted productivity and improved the developer experience, replacing Java for real-time services.Server-side
Forbes
By sharing over 80% of logic across iOS and Android, Forbes now rolls out new features simultaneously on both platforms, keeping the flexibility to withhold or customize features based on the specific platform.Kotlin Multiplatform
Atlassian
Atlassian adopted Kotlin for the Jira Software cloud, leveraging its Java compatibility for seamless integration and minimizing migration challenges. Kotlin's ease of use improved developer productivity and boosted team satisfaction and efficiency.Server-side

Share code on your terms and for different platforms

Simplify the development of cross-platform projects with Kotlin Multiplatform. It reduces time spent writing and maintaining the same code for different platforms while retaining the flexibility and benefits of native programming. Kotlin applications will work on different operating systems, such as iOS, Android, macOS, Windows, Linux, watchOS, and others.
Learn about Kotlin Multiplatform

Kotlin + AI

JetBrains is investing in AI models tailored for Kotlin, providing open data, benchmarks, and AI-native tooling integrated into your workflow.

At the same time, Kotlin makes it easy to build your own AI-powered features with seamless backend integrations and a growing ecosystem.

What you get with Kotlin + AI

  • Strong support across JetBrains AI tools like AI Assistant and Junie
  • Robust functionality for building AI-powered apps on the JVM
  • Native integration with tools like Spring AI and LangChain4j
  • Open data and benchmarks for better code generation

Build your own AI agents with Koog

Koog is JetBrains’ new Kotlin-native framework for creating powerful AI agents that run locally, interact with tools, and automate complex tasks. Whether you’re developing a simple chat assistant or an advanced multi-step workflow, Koog gives you full control with clean Kotlin code – no external services are required. Build, extend, and experiment with AI agents entirely in Kotlin.

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Big, friendly and helpful community

Kotlin has great support and many contributors in its fast-growing global community. Enjoy the benefits of a rich ecosystem with a wide range of community libraries. Help is never far away — consult extensive community resources or ask the Kotlin team directly.

Kotlin Foundation

Actively supports community efforts in developing the Kotlin ecosystem.

Start using Kotlin today!