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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

Kodee’s Kotlin Roundup: Too Much News to Keep Quiet About

November 26, 2025

Kodee’s Kotlin Roundup: Too Much News to Keep Quiet About

I’ve gathered the latest Kotlin highlights for you – from the Kotlin Reddit AMA and documentation updates to learning programs and Google Summer of Code 2025 projects. Whether you’re here to stay up to date or just looking for something interesting to explore, there’s plenty to dive into. Where You Can Learn More YouTube Highlights

Building AI Agents in Kotlin – Part 2: A Deeper Dive Into Tools

November 26, 2025

Building AI Agents in Kotlin – Part 2: A Deeper Dive Into Tools

In the previous article, we saw how to build a basic coding agent with list, read, write, and edit capabilities. Today, we’ll dive into how to extend the agents’ capabilities by creating additional tools within the Koog framework. As an example, we’ll be building an ExecuteShellCommandTool, teaching our agent to run code and close the […]

The Ultimate KMP Watchlist: Level Up Your Skills in 10 Talks

November 24, 2025

The Ultimate KMP Watchlist: Level Up Your Skills in 10 Talks

The best way to skip the “beginner mistakes” phase is to learn from the teams who have already solved them at scale. For Week 3 of KMP Level Up, we’ve curated the Top 10 KotlinConf talks that cover the full spectrum of adoption, from massive production case studies to deep dives into the compiler. Whether […]

Amper Update, November 2025 – Extensibility Preview

November 24, 2025

Amper Update, November 2025 – Extensibility Preview

Amper 0.9.0 is out, and it brings the first version of our extensibility prototype! 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 latest features, use IntelliJ IDEA 2025.3 Beta (or newer). New Amper website We revamped our […]

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!