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Kotlin for Backend

Spring support, Java interop, coroutines.

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Kotlin for Server

Spring support, Java interop, coroutines.

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Kotlin for Backend

A simple way to boost your coding joy.

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Kotlin for Server

A simple way to boost your coding joy.

Try Now
Kotlin for Backend

A simple way to boost your productivity.

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Kotlin for Server

A simple way to boost your productivity.

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Latest news

Build a Kotlin Multiplatform Project and Win a Trip to KotlinConf 2026

October 9, 2025

Build a Kotlin Multiplatform Project and Win a Trip to KotlinConf 2026

This year’s Kotlin Multiplatform Contest for students and recent graduates is open. Build a project using KMP, and it could take you to KotlinConf 2026 in Munich, Germany! Whether you are already exploring Kotlin Multiplatform or just curious about how far you can take shared Kotlin code, seize the chance to challenge yourself, stand out, […]

Crafting Your KotlinConf Proposal: Expert Tips to  Help You Stand Out

October 8, 2025

Crafting Your KotlinConf Proposal: Expert Tips to  Help You Stand Out

Thinking about sharing your Kotlin expertise on the big stage? KotlinConf is the premier event for all things Kotlin, and getting a talk accepted for inclusion in the conference is a fantastic way to contribute to the community and elevate your profile. However, submitting a talk proposal, especially for the first time, can feel daunting. […]

Amper Update, October 2025 – Compose Hot Reload and UX Improvements

October 3, 2025

Amper Update, October 2025 – Compose Hot Reload and UX Improvements

Amper 0.8.0 is out, with Compose Hot Reload, a customizable Kotlin compiler version, new JavaScript and Wasm platforms, and many other improvements to both the IDE and CLI experience. Read on for all of the details, and see the release notes for the full list of changes and bug fixes. To get support for Amper’s […]

Koog × A2A: Building Connected AI Agents in Kotlin

October 2, 2025

Koog × A2A: Building Connected AI Agents in Kotlin

If you’ve ever tried building a system of multiple AI agents, you’ve probably run into the problem. It starts simple enough: You’ve got one agent writing blog posts, another proofreading them, and maybe a third suggesting or generating images. Individually, they’re effective. But getting them to work together? That’s where things might start falling apart. […]

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!