Kotlin by JetBrains
@kotlinlang.org
Kotlin is a programming language that makes coding concise, cross-platform, and fun — https://kotlinlang.org/
Video tutorials http://kotl.in/video
News http://kotl.in/news
Community discussions http://kotl.in/slack
Video tutorials http://kotl.in/video
News http://kotl.in/news
Community discussions http://kotl.in/slack
📢 The Kotlin Multiplatform Contest deadline is January 12!
Students and recent grads, this is your chance to win a trip to KotlinConf 2026 in Munich – with tickets and hotels covered.
All valid entries receive Kotlin souvenirs!
Take part ⤵️
kotl.in/cntst-rmdr
Students and recent grads, this is your chance to win a trip to KotlinConf 2026 in Munich – with tickets and hotels covered.
All valid entries receive Kotlin souvenirs!
Take part ⤵️
kotl.in/cntst-rmdr
December 23, 2025 at 1:56 PM
📢 The Kotlin Multiplatform Contest deadline is January 12!
Students and recent grads, this is your chance to win a trip to KotlinConf 2026 in Munich – with tickets and hotels covered.
All valid entries receive Kotlin souvenirs!
Take part ⤵️
kotl.in/cntst-rmdr
Students and recent grads, this is your chance to win a trip to KotlinConf 2026 in Munich – with tickets and hotels covered.
All valid entries receive Kotlin souvenirs!
Take part ⤵️
kotl.in/cntst-rmdr
🌱 Spring Boot 4 is taking Kotlin support to the next level!
Thanks to a Kotlin 2.2 baseline, deeper null-safety, better serialization, and coroutine context propagation, Spring is now even more Kotlin-friendly.
Dive into the latest improvements 👉 https://kotl.in/im2t40
Thanks to a Kotlin 2.2 baseline, deeper null-safety, better serialization, and coroutine context propagation, Spring is now even more Kotlin-friendly.
Dive into the latest improvements 👉 https://kotl.in/im2t40
Next level Kotlin support in Spring Boot 4
Level up your Java code and explore what Spring can do for you.
kotl.in
December 21, 2025 at 4:47 PM
🌱 Spring Boot 4 is taking Kotlin support to the next level!
Thanks to a Kotlin 2.2 baseline, deeper null-safety, better serialization, and coroutine context propagation, Spring is now even more Kotlin-friendly.
Dive into the latest improvements 👉 https://kotl.in/im2t40
Thanks to a Kotlin 2.2 baseline, deeper null-safety, better serialization, and coroutine context propagation, Spring is now even more Kotlin-friendly.
Dive into the latest improvements 👉 https://kotl.in/im2t40
🎁 Holiday shopping hack – Buy a ticket to KotlinConf and enjoy:
✅ Loads of inspiration
✅ Talks that spark new ideas
✅ Some dev happiness
Get one for yourself or a friend 👇
https://kotl.in/kc-gift-kbs
✅ Loads of inspiration
✅ Talks that spark new ideas
✅ Some dev happiness
Get one for yourself or a friend 👇
https://kotl.in/kc-gift-kbs
December 19, 2025 at 2:11 PM
🎁 Holiday shopping hack – Buy a ticket to KotlinConf and enjoy:
✅ Loads of inspiration
✅ Talks that spark new ideas
✅ Some dev happiness
Get one for yourself or a friend 👇
https://kotl.in/kc-gift-kbs
✅ Loads of inspiration
✅ Talks that spark new ideas
✅ Some dev happiness
Get one for yourself or a friend 👇
https://kotl.in/kc-gift-kbs
✨ Introducing the Golden Kodee Community Awards ✨
We’re celebrating the people who make the Kotlin community shine – educators, creators, organizers, and innovators.
Think you deserve an award?
🏆 Nominate yourself now! → kotl.in/golden-kodee...
We’re celebrating the people who make the Kotlin community shine – educators, creators, organizers, and innovators.
Think you deserve an award?
🏆 Nominate yourself now! → kotl.in/golden-kodee...
Golden Kodee Community Awards | KotlinConf 2026, May 20–22, Munich
KotlinConf is the official Kotlin conference by JetBrains. It is a place for the community to gather and discuss all things Kotlin.
kotl.in
December 19, 2025 at 10:51 AM
✨ Introducing the Golden Kodee Community Awards ✨
We’re celebrating the people who make the Kotlin community shine – educators, creators, organizers, and innovators.
Think you deserve an award?
🏆 Nominate yourself now! → kotl.in/golden-kodee...
We’re celebrating the people who make the Kotlin community shine – educators, creators, organizers, and innovators.
Think you deserve an award?
🏆 Nominate yourself now! → kotl.in/golden-kodee...
Reposted by Kotlin by JetBrains
⭐ 🎤 Kotlin powers products at companies like Meta, AWS, Duolingo, Uber, and more. At KotlinConf'25, these teams revealed how they use Kotlin to solve real engineering challenges in production.
Dive into their stories 👉 https://kotl.in/co3t0q
Dive into their stories 👉 https://kotl.in/co3t0q
Industry Leaders on the KotlinConf'25 Stage: What Global Brands Built With Kotlin | The Kotlin Blog
At KotlinConf'25, global brands like Meta, AWS, Duolingo, and Uber shared real-world engineering stories.
blog.jetbrains.com
December 18, 2025 at 6:04 PM
⭐ 🎤 Kotlin powers products at companies like Meta, AWS, Duolingo, Uber, and more. At KotlinConf'25, these teams revealed how they use Kotlin to solve real engineering challenges in production.
Dive into their stories 👉 https://kotl.in/co3t0q
Dive into their stories 👉 https://kotl.in/co3t0q
Need manager approval for KotlinConf?
Use our ready-made templates and join us in Munich, May 20–22.
👉 https://kotl.in/ma-kbs
Use our ready-made templates and join us in Munich, May 20–22.
👉 https://kotl.in/ma-kbs
December 18, 2025 at 2:22 PM
Need manager approval for KotlinConf?
Use our ready-made templates and join us in Munich, May 20–22.
👉 https://kotl.in/ma-kbs
Use our ready-made templates and join us in Munich, May 20–22.
👉 https://kotl.in/ma-kbs
A clean, modern intro to Spring Boot with instant switching between Java and Kotlin examples.
Worth a look if you’re comparing the two for your next project 👇 https://kotl.in/pkj849
Worth a look if you’re comparing the two for your next project 👇 https://kotl.in/pkj849
Getting Started | Building an Application with Spring Boot
Learn how to build an application with minimal configuration.
kotl.in
December 18, 2025 at 11:57 AM
A clean, modern intro to Spring Boot with instant switching between Java and Kotlin examples.
Worth a look if you’re comparing the two for your next project 👇 https://kotl.in/pkj849
Worth a look if you’re comparing the two for your next project 👇 https://kotl.in/pkj849
Thinking of taking your Android app multiplatform?
Together with the @androiddevs.bsky.social team and using Jetcaster as an example, we’ve created a migration guide that includes a repo where every commit represents a working state.
👉 https://kotl.in/g1q3h5
Together with the @androiddevs.bsky.social team and using Jetcaster as an example, we’ve created a migration guide that includes a repo where every commit represents a working state.
👉 https://kotl.in/g1q3h5
Migrating a Jetpack Compose app to Kotlin Multiplatform | Kotlin Multiplatform
kotlinlang.org
December 17, 2025 at 4:00 PM
Thinking of taking your Android app multiplatform?
Together with the @androiddevs.bsky.social team and using Jetcaster as an example, we’ve created a migration guide that includes a repo where every commit represents a working state.
👉 https://kotl.in/g1q3h5
Together with the @androiddevs.bsky.social team and using Jetcaster as an example, we’ve created a migration guide that includes a repo where every commit represents a working state.
👉 https://kotl.in/g1q3h5
💡 Did you know? Ktor has a built-in test framework for REST APIs.
Run tests in isolation, verify endpoints, and serialize types safely.
Docs 👉 https://kotl.in/ktor-test
Run tests in isolation, verify endpoints, and serialize types safely.
Docs 👉 https://kotl.in/ktor-test
December 16, 2025 at 3:54 PM
💡 Did you know? Ktor has a built-in test framework for REST APIs.
Run tests in isolation, verify endpoints, and serialize types safely.
Docs 👉 https://kotl.in/ktor-test
Run tests in isolation, verify endpoints, and serialize types safely.
Docs 👉 https://kotl.in/ktor-test
💸 Kotlin’s gaining traction in fintech!
ING’s engineers rebuilt their core payment engine in Kotlin – improving code quality, speeding up delivery, and fostering a growing internal Kotlin community.
🎥 Watch the story: https://www.youtube.com/watch?v=mexcjkGZIm8
ING’s engineers rebuilt their core payment engine in Kotlin – improving code quality, speeding up delivery, and fostering a growing internal Kotlin community.
🎥 Watch the story: https://www.youtube.com/watch?v=mexcjkGZIm8
Why ING Chooses Kotlin for Server-Side
YouTube video by Kotlin by JetBrains
www.youtube.com
December 16, 2025 at 2:13 PM
💸 Kotlin’s gaining traction in fintech!
ING’s engineers rebuilt their core payment engine in Kotlin – improving code quality, speeding up delivery, and fostering a growing internal Kotlin community.
🎥 Watch the story: https://www.youtube.com/watch?v=mexcjkGZIm8
ING’s engineers rebuilt their core payment engine in Kotlin – improving code quality, speeding up delivery, and fostering a growing internal Kotlin community.
🎥 Watch the story: https://www.youtube.com/watch?v=mexcjkGZIm8
KotlinConf workshops dive into the most in-demand areas, including:
✨ Kotlin and Compose Multiplatform
✨ Backend with Spring and Ktor
✨ AI agents in Kotlin
✨ Coroutines
✨ Functional Kotlin
🗓️ May 20 • 📍 Munich
Sign up today 👇
https://kotl.in/ws-2026-kbs
✨ Kotlin and Compose Multiplatform
✨ Backend with Spring and Ktor
✨ AI agents in Kotlin
✨ Coroutines
✨ Functional Kotlin
🗓️ May 20 • 📍 Munich
Sign up today 👇
https://kotl.in/ws-2026-kbs
December 16, 2025 at 1:42 PM
KotlinConf workshops dive into the most in-demand areas, including:
✨ Kotlin and Compose Multiplatform
✨ Backend with Spring and Ktor
✨ AI agents in Kotlin
✨ Coroutines
✨ Functional Kotlin
🗓️ May 20 • 📍 Munich
Sign up today 👇
https://kotl.in/ws-2026-kbs
✨ Kotlin and Compose Multiplatform
✨ Backend with Spring and Ktor
✨ AI agents in Kotlin
✨ Coroutines
✨ Functional Kotlin
🗓️ May 20 • 📍 Munich
Sign up today 👇
https://kotl.in/ws-2026-kbs
Reposted by Kotlin by JetBrains
👀 We’ve been working on something big – and let’s just say, you had something to do with it.
Stay tuned!
📮 https://kotl.in/gkodee-blu
Stay tuned!
📮 https://kotl.in/gkodee-blu
December 16, 2025 at 10:30 AM
👀 We’ve been working on something big – and let’s just say, you had something to do with it.
Stay tuned!
📮 https://kotl.in/gkodee-blu
Stay tuned!
📮 https://kotl.in/gkodee-blu
📓 Kotlin Notebooks let you run server-side experiments inline:
- query a DB
- test Ktor APIs
- prototype with coroutines.
And more!
Try it in @IntelliJIDEA
https://kotl.in/cf07id
- query a DB
- test Ktor APIs
- prototype with coroutines.
And more!
Try it in @IntelliJIDEA
https://kotl.in/cf07id
Get started with Kotlin Notebook | Kotlin
kotl.in
December 15, 2025 at 3:53 PM
📓 Kotlin Notebooks let you run server-side experiments inline:
- query a DB
- test Ktor APIs
- prototype with coroutines.
And more!
Try it in @IntelliJIDEA
https://kotl.in/cf07id
- query a DB
- test Ktor APIs
- prototype with coroutines.
And more!
Try it in @IntelliJIDEA
https://kotl.in/cf07id
🚀 Build dynamic web apps without the SPA overhead!
Anders Sveen shows how the combination of HTMX, Ktor, and kotlinx.html can simplify full-stack Kotlin. A must-watch! https://kotl.in/7stxd6
Anders Sveen shows how the combination of HTMX, Ktor, and kotlinx.html can simplify full-stack Kotlin. A must-watch! https://kotl.in/7stxd6
Simplifying Full-Stack Kotlin: A Fresh Take with HTMX and Ktor | Anders Sveen
YouTube video by Kotlin by JetBrains
youtu.be
December 14, 2025 at 5:31 AM
🚀 Build dynamic web apps without the SPA overhead!
Anders Sveen shows how the combination of HTMX, Ktor, and kotlinx.html can simplify full-stack Kotlin. A must-watch! https://kotl.in/7stxd6
Anders Sveen shows how the combination of HTMX, Ktor, and kotlinx.html can simplify full-stack Kotlin. A must-watch! https://kotl.in/7stxd6
🚀 Benchmark smarter with kotlinx-benchmark and Kotlin Notebook!
Load results as DataFrames, explore them interactively, and visualize performance with charts – all in one place.
Learn more in the blog post 👇 https://kotl.in/6so8mf
Load results as DataFrames, explore them interactively, and visualize performance with charts – all in one place.
Learn more in the blog post 👇 https://kotl.in/6so8mf
A Better Way to Explore kotlinx-benchmark Results with Kotlin Notebooks | The Kotlin Blog
kotlinx-benchmark lets you measure and compare performance across implementations or hardware. Learn how to explore your benchmarks with Kotlin Notebooks.
kotl.in
December 12, 2025 at 4:22 PM
🚀 Benchmark smarter with kotlinx-benchmark and Kotlin Notebook!
Load results as DataFrames, explore them interactively, and visualize performance with charts – all in one place.
Learn more in the blog post 👇 https://kotl.in/6so8mf
Load results as DataFrames, explore them interactively, and visualize performance with charts – all in one place.
Learn more in the blog post 👇 https://kotl.in/6so8mf
🚨 Today: Kotlin Ecosystem AMA on r/Kotlin
🕒 3:00–7:00 pm CET
Bring your Kotlin questions on language, multiplatform, backend, AI, libraries, docs, user research, and more 👇
https://kotl.in/reddit-ama
🕒 3:00–7:00 pm CET
Bring your Kotlin questions on language, multiplatform, backend, AI, libraries, docs, user research, and more 👇
https://kotl.in/reddit-ama
December 11, 2025 at 12:47 PM
🚨 Today: Kotlin Ecosystem AMA on r/Kotlin
🕒 3:00–7:00 pm CET
Bring your Kotlin questions on language, multiplatform, backend, AI, libraries, docs, user research, and more 👇
https://kotl.in/reddit-ama
🕒 3:00–7:00 pm CET
Bring your Kotlin questions on language, multiplatform, backend, AI, libraries, docs, user research, and more 👇
https://kotl.in/reddit-ama
🚀 Spring + Kotlin coroutines: write sequential code that runs async. No more CompletableFuture chains or reactive overload.
Docs 👉 https://kotl.in/u95jk8
Docs 👉 https://kotl.in/u95jk8
December 11, 2025 at 11:57 AM
🚀 Spring + Kotlin coroutines: write sequential code that runs async. No more CompletableFuture chains or reactive overload.
Docs 👉 https://kotl.in/u95jk8
Docs 👉 https://kotl.in/u95jk8
New update to the Spring docs! 🎉
The “Consuming a RESTful Web Service” guide now includes examples in Kotlin and Java, with easy language switching via interactive tabs.
Check it out 👇 https://kotl.in/vivgrq
The “Consuming a RESTful Web Service” guide now includes examples in Kotlin and Java, with easy language switching via interactive tabs.
Check it out 👇 https://kotl.in/vivgrq
Getting Started | Consuming a RESTful Web Service
Learn how to retrieve web page data with Spring's RestTemplate.
kotl.in
December 9, 2025 at 5:56 PM
New update to the Spring docs! 🎉
The “Consuming a RESTful Web Service” guide now includes examples in Kotlin and Java, with easy language switching via interactive tabs.
Check it out 👇 https://kotl.in/vivgrq
The “Consuming a RESTful Web Service” guide now includes examples in Kotlin and Java, with easy language switching via interactive tabs.
Check it out 👇 https://kotl.in/vivgrq
❓Ask us anything about Kotlin, multiplatform, backend, libraries, docs, education, user research, and Kotlin + AI.
Kotlin Ecosystem Reddit AMA on r/Kotlin
🗓️ Dec 11 · 🕒 3:00–7:00 pm CET
👇 Check out the topics and participants in the thread.
https://kotl.in/dpkmdp
Kotlin Ecosystem Reddit AMA on r/Kotlin
🗓️ Dec 11 · 🕒 3:00–7:00 pm CET
👇 Check out the topics and participants in the thread.
https://kotl.in/dpkmdp
From the Kotlin community on Reddit: Kotlin Ecosystem AMA – December 11 (3–7 pm CET)
Explore this post and more from the Kotlin community
www.reddit.com
December 9, 2025 at 3:33 PM
❓Ask us anything about Kotlin, multiplatform, backend, libraries, docs, education, user research, and Kotlin + AI.
Kotlin Ecosystem Reddit AMA on r/Kotlin
🗓️ Dec 11 · 🕒 3:00–7:00 pm CET
👇 Check out the topics and participants in the thread.
https://kotl.in/dpkmdp
Kotlin Ecosystem Reddit AMA on r/Kotlin
🗓️ Dec 11 · 🕒 3:00–7:00 pm CET
👇 Check out the topics and participants in the thread.
https://kotl.in/dpkmdp
Start @kotlinconf.com with a full day of training led by Kotlin experts.
🗓️ May 20 • 📍 Munich
Here's what you'll walk away with:
🔥 Six hours of hands-on experience
🎯 Direct feedback
📦 Prep materials
📜 A certificate of attendance
Sign up today 👇
https://kotl.in/ws-2026-kbs
🗓️ May 20 • 📍 Munich
Here's what you'll walk away with:
🔥 Six hours of hands-on experience
🎯 Direct feedback
📦 Prep materials
📜 A certificate of attendance
Sign up today 👇
https://kotl.in/ws-2026-kbs
Workshops | KotlinConf 2026, May 20–22, Munich
KotlinConf is the official Kotlin conference by JetBrains. It is a place for the community to gather and discuss all things Kotlin.
kotl.in
December 9, 2025 at 1:36 PM
Start @kotlinconf.com with a full day of training led by Kotlin experts.
🗓️ May 20 • 📍 Munich
Here's what you'll walk away with:
🔥 Six hours of hands-on experience
🎯 Direct feedback
📦 Prep materials
📜 A certificate of attendance
Sign up today 👇
https://kotl.in/ws-2026-kbs
🗓️ May 20 • 📍 Munich
Here's what you'll walk away with:
🔥 Six hours of hands-on experience
🎯 Direct feedback
📦 Prep materials
📜 A certificate of attendance
Sign up today 👇
https://kotl.in/ws-2026-kbs
🚗 From two pilot projects to a Kotlin-first backend!
Mercedes-Benz.io refactored its Java-based systems with Kotlin to reduce boilerplate, speed up development, and enhance stability across its digital ecosystem.
For more on Kotlin for backend 👉 https://kotl.in/server-side-landing-ms
Mercedes-Benz.io refactored its Java-based systems with Kotlin to reduce boilerplate, speed up development, and enhance stability across its digital ecosystem.
For more on Kotlin for backend 👉 https://kotl.in/server-side-landing-ms
December 8, 2025 at 3:50 PM
🚗 From two pilot projects to a Kotlin-first backend!
Mercedes-Benz.io refactored its Java-based systems with Kotlin to reduce boilerplate, speed up development, and enhance stability across its digital ecosystem.
For more on Kotlin for backend 👉 https://kotl.in/server-side-landing-ms
Mercedes-Benz.io refactored its Java-based systems with Kotlin to reduce boilerplate, speed up development, and enhance stability across its digital ecosystem.
For more on Kotlin for backend 👉 https://kotl.in/server-side-landing-ms
Reposted by Kotlin by JetBrains
KotlinConf’25 was one for the books – full rooms, big announcements, and a legendary party. 🎉
We’re still buzzing!
✨ Want to be part of the experience in 2026?
👉 Come write your own KotlinConf story: https://kotlinconf.com/
We’re still buzzing!
✨ Want to be part of the experience in 2026?
👉 Come write your own KotlinConf story: https://kotlinconf.com/
December 4, 2025 at 6:23 PM
KotlinConf’25 was one for the books – full rooms, big announcements, and a legendary party. 🎉
We’re still buzzing!
✨ Want to be part of the experience in 2026?
👉 Come write your own KotlinConf story: https://kotlinconf.com/
We’re still buzzing!
✨ Want to be part of the experience in 2026?
👉 Come write your own KotlinConf story: https://kotlinconf.com/
⚡ Kotlin coroutines simplify async programming on the server:
✔️ Structured concurrency
✔️ Cancellation
✔️ Clean, readable code
Learn more 👇 https://kotlinlang.org/docs/coroutines-basics.html
✔️ Structured concurrency
✔️ Cancellation
✔️ Clean, readable code
Learn more 👇 https://kotlinlang.org/docs/coroutines-basics.html
Coroutines guide | Kotlin
kotlinlang.org
December 7, 2025 at 2:00 PM
⚡ Kotlin coroutines simplify async programming on the server:
✔️ Structured concurrency
✔️ Cancellation
✔️ Clean, readable code
Learn more 👇 https://kotlinlang.org/docs/coroutines-basics.html
✔️ Structured concurrency
✔️ Cancellation
✔️ Clean, readable code
Learn more 👇 https://kotlinlang.org/docs/coroutines-basics.html
🟢 Using Spring Boot with Kotlin results in less boilerplate and more clarity.
With data classes and @ConfigurationProperties, you get concise, immutable, and type-safe configuration objects that are easy to maintain.
Get started with the official documentation 👇 https://kotl.in/3vlw6o
With data classes and @ConfigurationProperties, you get concise, immutable, and type-safe configuration objects that are easy to maintain.
Get started with the official documentation 👇 https://kotl.in/3vlw6o
Getting Started | Building web applications with Spring Boot and Kotlin
Learn how to easily build and test web applications with Spring, Kotlin, Junit 5 and JPA
kotl.in
December 6, 2025 at 12:11 PM
🟢 Using Spring Boot with Kotlin results in less boilerplate and more clarity.
With data classes and @ConfigurationProperties, you get concise, immutable, and type-safe configuration objects that are easy to maintain.
Get started with the official documentation 👇 https://kotl.in/3vlw6o
With data classes and @ConfigurationProperties, you get concise, immutable, and type-safe configuration objects that are easy to maintain.
Get started with the official documentation 👇 https://kotl.in/3vlw6o
🎉 Join the Kotlin Ecosystem Reddit AMA!
🗓️ Dec 11, 3:00–7:00 pm CET
💬 r/Kotlin
Chat with the Kotlin Ecosystem team about language updates, Kotlin Multiplatform, AI tooling, backend development, and more.
https://www.reddit.com/r/Kotlin/comments/1pdvlft/kotlin_ecosystem_ama_december_11_37_pm_cet/
🗓️ Dec 11, 3:00–7:00 pm CET
💬 r/Kotlin
Chat with the Kotlin Ecosystem team about language updates, Kotlin Multiplatform, AI tooling, backend development, and more.
https://www.reddit.com/r/Kotlin/comments/1pdvlft/kotlin_ecosystem_ama_december_11_37_pm_cet/
From the Kotlin community on Reddit: Kotlin Ecosystem AMA – December 11 (3–7 pm CET)
Explore this post and more from the Kotlin community
www.reddit.com
December 4, 2025 at 2:40 PM
🎉 Join the Kotlin Ecosystem Reddit AMA!
🗓️ Dec 11, 3:00–7:00 pm CET
💬 r/Kotlin
Chat with the Kotlin Ecosystem team about language updates, Kotlin Multiplatform, AI tooling, backend development, and more.
https://www.reddit.com/r/Kotlin/comments/1pdvlft/kotlin_ecosystem_ama_december_11_37_pm_cet/
🗓️ Dec 11, 3:00–7:00 pm CET
💬 r/Kotlin
Chat with the Kotlin Ecosystem team about language updates, Kotlin Multiplatform, AI tooling, backend development, and more.
https://www.reddit.com/r/Kotlin/comments/1pdvlft/kotlin_ecosystem_ama_december_11_37_pm_cet/