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January 26, 2026

Building AI Agents in Kotlin – Part 5: Teaching Agents to Forget

Previously in this series: Agents eventually run out of context. When they do, they crash, and you lose everything mid-task. We’ve been running GPT-5 Codex since Part 1. It scores 0.58 on SWE-bench Verified. We tried Claude Sonnet 4.5 next, which scored 0.6 and ran faster on most tasks. But complex problems hit Claude’s 200K […]

January 26, 2026

Meet the First Speakers Heading to KotlinConf 2026

With each KotlinConf, developers from around the world come together to learn from leading experts, explore the latest industry insights, and engage with the Kotlin community. KotlinConf’25 alone welcomed attendees from over 50 countries. KotlinConf’26 is just a few months away, and we’re excited to introduce the first round of speakers who will be joining […]

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 […]

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 […]

Kotlin blog

Why Kotlin?

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 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 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 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 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

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 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

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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.

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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

Learn about JetBrains AI Build AI apps with Kotlin

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.

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Start using Kotlin today!

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