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
🐳 Ready to take your Ktor app live?
With the Ktor Gradle plugin, packaging and deployment become simple and seamless. Check out this step‑by‑step guide to ensure smooth deployment 👉 https://kotl.in/tkzc0l
With the Ktor Gradle plugin, packaging and deployment become simple and seamless. Check out this step‑by‑step guide to ensure smooth deployment 👉 https://kotl.in/tkzc0l
November 27, 2025 at 3:01 PM
🐳 Ready to take your Ktor app live?
With the Ktor Gradle plugin, packaging and deployment become simple and seamless. Check out this step‑by‑step guide to ensure smooth deployment 👉 https://kotl.in/tkzc0l
With the Ktor Gradle plugin, packaging and deployment become simple and seamless. Check out this step‑by‑step guide to ensure smooth deployment 👉 https://kotl.in/tkzc0l
🗳️ Help us make Ktor better!
💬 Tell us what’s working, what’s missing, and what would make Ktor better for you.
Your feedback will help shape the next improvements to the framework, docs, and tools.
👉 Take the survey https://surveys.jetbrains.com/s3/05ddc3ebe003
💬 Tell us what’s working, what’s missing, and what would make Ktor better for you.
Your feedback will help shape the next improvements to the framework, docs, and tools.
👉 Take the survey https://surveys.jetbrains.com/s3/05ddc3ebe003
November 26, 2025 at 11:19 AM
🗳️ Help us make Ktor better!
💬 Tell us what’s working, what’s missing, and what would make Ktor better for you.
Your feedback will help shape the next improvements to the framework, docs, and tools.
👉 Take the survey https://surveys.jetbrains.com/s3/05ddc3ebe003
💬 Tell us what’s working, what’s missing, and what would make Ktor better for you.
Your feedback will help shape the next improvements to the framework, docs, and tools.
👉 Take the survey https://surveys.jetbrains.com/s3/05ddc3ebe003
🖤 Black Friday, but make it Kotlin. 💜
✨ Get 20% off KotlinConf 2026 tickets ✨
The offer is valid through November 30.
🎟️ https://kotl.in/conf26-blfr-bl 🎟️
✨ Get 20% off KotlinConf 2026 tickets ✨
The offer is valid through November 30.
🎟️ https://kotl.in/conf26-blfr-bl 🎟️
November 26, 2025 at 9:00 AM
🖤 Black Friday, but make it Kotlin. 💜
✨ Get 20% off KotlinConf 2026 tickets ✨
The offer is valid through November 30.
🎟️ https://kotl.in/conf26-blfr-bl 🎟️
✨ Get 20% off KotlinConf 2026 tickets ✨
The offer is valid through November 30.
🎟️ https://kotl.in/conf26-blfr-bl 🎟️
Week 3 of #KMPLevelUp is live! 🚀 We’ve curated the definitive KMP Watchlist. See how:
🦉 Duolingo ships to 40M+ users
🍔 McDonald’s shares navigation logic
⚡️ Meetup made their iOS app faster with KMP
Get the playlist & register for the expert webinar ➡️ jb.gg/vbl7v4
🦉 Duolingo ships to 40M+ users
🍔 McDonald’s shares navigation logic
⚡️ Meetup made their iOS app faster with KMP
Get the playlist & register for the expert webinar ➡️ jb.gg/vbl7v4
November 24, 2025 at 5:04 PM
Week 3 of #KMPLevelUp is live! 🚀 We’ve curated the definitive KMP Watchlist. See how:
🦉 Duolingo ships to 40M+ users
🍔 McDonald’s shares navigation logic
⚡️ Meetup made their iOS app faster with KMP
Get the playlist & register for the expert webinar ➡️ jb.gg/vbl7v4
🦉 Duolingo ships to 40M+ users
🍔 McDonald’s shares navigation logic
⚡️ Meetup made their iOS app faster with KMP
Get the playlist & register for the expert webinar ➡️ jb.gg/vbl7v4
📹 Registration for our #KMPLevelUp career webinar is now open! Get your questions ready for legends like Jake Wharton, Zac Sweers, and other Android experts.
And ICYMI, the 5-hour CMP crash course is the perfect weekend project.
Register & watch here: jb.gg/vbl7v4
And ICYMI, the 5-hour CMP crash course is the perfect weekend project.
Register & watch here: jb.gg/vbl7v4
November 21, 2025 at 5:12 PM
📹 Registration for our #KMPLevelUp career webinar is now open! Get your questions ready for legends like Jake Wharton, Zac Sweers, and other Android experts.
And ICYMI, the 5-hour CMP crash course is the perfect weekend project.
Register & watch here: jb.gg/vbl7v4
And ICYMI, the 5-hour CMP crash course is the perfect weekend project.
Register & watch here: jb.gg/vbl7v4
📢 Help us improve Kotlin docs!
Share your insights on Kotlin’s documentation to help us enhance your developer experience.
➡️ You'll need a Chromium-based desktop browser to take part in the study. Check if you qualify to participate in our research: https://surveys.jetbrains.com/s3/kotlin-docs-t
Share your insights on Kotlin’s documentation to help us enhance your developer experience.
➡️ You'll need a Chromium-based desktop browser to take part in the study. Check if you qualify to participate in our research: https://surveys.jetbrains.com/s3/kotlin-docs-t
November 20, 2025 at 2:09 PM
📢 Help us improve Kotlin docs!
Share your insights on Kotlin’s documentation to help us enhance your developer experience.
➡️ You'll need a Chromium-based desktop browser to take part in the study. Check if you qualify to participate in our research: https://surveys.jetbrains.com/s3/kotlin-docs-t
Share your insights on Kotlin’s documentation to help us enhance your developer experience.
➡️ You'll need a Chromium-based desktop browser to take part in the study. Check if you qualify to participate in our research: https://surveys.jetbrains.com/s3/kotlin-docs-t
Ready for a deep dive into Compose Multiplatform? 🚀
For Week 2 of #KMPLevelUp, we've partnered with
Philipp Lackner to bring you a FREE 5-hour crash course.
Want to go even deeper? Find the 30% discount for his premium course on our learning hub.
Get both here ➡️ jb.gg/vbl7v4
For Week 2 of #KMPLevelUp, we've partnered with
Philipp Lackner to bring you a FREE 5-hour crash course.
Want to go even deeper? Find the 30% discount for his premium course on our learning hub.
Get both here ➡️ jb.gg/vbl7v4
November 17, 2025 at 4:59 PM
Ready for a deep dive into Compose Multiplatform? 🚀
For Week 2 of #KMPLevelUp, we've partnered with
Philipp Lackner to bring you a FREE 5-hour crash course.
Want to go even deeper? Find the 30% discount for his premium course on our learning hub.
Get both here ➡️ jb.gg/vbl7v4
For Week 2 of #KMPLevelUp, we've partnered with
Philipp Lackner to bring you a FREE 5-hour crash course.
Want to go even deeper? Find the 30% discount for his premium course on our learning hub.
Get both here ➡️ jb.gg/vbl7v4
Not sure where to start with Kotlin Multiplatform and Compose Multiplatform? Here’s your roadmap📍
Week 1 of #KMPLevelUp drops the Course Matrix with:
📚 best learning paths
🎯 clear skill outcomes
🤝 picks from our Dev Advocates
Start your journey: jb.gg/vbl7v4
Week 1 of #KMPLevelUp drops the Course Matrix with:
📚 best learning paths
🎯 clear skill outcomes
🤝 picks from our Dev Advocates
Start your journey: jb.gg/vbl7v4
November 13, 2025 at 2:51 PM
Not sure where to start with Kotlin Multiplatform and Compose Multiplatform? Here’s your roadmap📍
Week 1 of #KMPLevelUp drops the Course Matrix with:
📚 best learning paths
🎯 clear skill outcomes
🤝 picks from our Dev Advocates
Start your journey: jb.gg/vbl7v4
Week 1 of #KMPLevelUp drops the Course Matrix with:
📚 best learning paths
🎯 clear skill outcomes
🤝 picks from our Dev Advocates
Start your journey: jb.gg/vbl7v4
🖼️ Animation tuning as an art form? At KotlinConf25, @nicole-terc.bsky.social showed us how to master AnimationSpec for custom animations.
Catch the full session here:
https://youtu.be/clDGqPfaIto?si=Fud8Tagdk8ZE2bPM
Catch the full session here:
https://youtu.be/clDGqPfaIto?si=Fud8Tagdk8ZE2bPM
November 11, 2025 at 2:16 PM
🖼️ Animation tuning as an art form? At KotlinConf25, @nicole-terc.bsky.social showed us how to master AnimationSpec for custom animations.
Catch the full session here:
https://youtu.be/clDGqPfaIto?si=Fud8Tagdk8ZE2bPM
Catch the full session here:
https://youtu.be/clDGqPfaIto?si=Fud8Tagdk8ZE2bPM
📦 Library publication is much easier in Kotlin 2.2.20!
New Gradle tasks help generate key pairs, upload public keys, and verify everything locally before publishing to Maven Central.
👉 Learn more: https://kotl.in/libpb
New Gradle tasks help generate key pairs, upload public keys, and verify everything locally before publishing to Maven Central.
👉 Learn more: https://kotl.in/libpb
November 10, 2025 at 4:50 PM
📦 Library publication is much easier in Kotlin 2.2.20!
New Gradle tasks help generate key pairs, upload public keys, and verify everything locally before publishing to Maven Central.
👉 Learn more: https://kotl.in/libpb
New Gradle tasks help generate key pairs, upload public keys, and verify everything locally before publishing to Maven Central.
👉 Learn more: https://kotl.in/libpb
📣 Calling all Ktor users! We’d love your input! Take our annual survey and share your thoughts, challenges, and ideas to help us make the framework even better.
Your feedback shapes the future of Ktor 🚀
Take the survey 👉 surveys.jetbrains.com/s3/05ddc3ebe...
Your feedback shapes the future of Ktor 🚀
Take the survey 👉 surveys.jetbrains.com/s3/05ddc3ebe...
November 6, 2025 at 9:15 AM
📣 Calling all Ktor users! We’d love your input! Take our annual survey and share your thoughts, challenges, and ideas to help us make the framework even better.
Your feedback shapes the future of Ktor 🚀
Take the survey 👉 surveys.jetbrains.com/s3/05ddc3ebe...
Your feedback shapes the future of Ktor 🚀
Take the survey 👉 surveys.jetbrains.com/s3/05ddc3ebe...
We’re running our yearly Kotlin Multiplatform survey to understand how the ecosystem is growing, how our recent releases are performing, and where to focus our efforts next.
Your experiences matter!
Take a few minutes to share your feedback 👉 https://surveys.jetbrains.com/s3/KMP-Survey-2025-B
Your experiences matter!
Take a few minutes to share your feedback 👉 https://surveys.jetbrains.com/s3/KMP-Survey-2025-B
October 28, 2025 at 1:45 PM
We’re running our yearly Kotlin Multiplatform survey to understand how the ecosystem is growing, how our recent releases are performing, and where to focus our efforts next.
Your experiences matter!
Take a few minutes to share your feedback 👉 https://surveys.jetbrains.com/s3/KMP-Survey-2025-B
Your experiences matter!
Take a few minutes to share your feedback 👉 https://surveys.jetbrains.com/s3/KMP-Survey-2025-B
💜 Don’t miss what’s next in Kotlin.
Get bite-sized updates, inspiration, and sneak peeks delivered right to your inbox.
Subscribe and stay in the loop 👉 https://kotl.in/news
📰 The new edition is coming soon!
Get bite-sized updates, inspiration, and sneak peeks delivered right to your inbox.
Subscribe and stay in the loop 👉 https://kotl.in/news
📰 The new edition is coming soon!
October 25, 2025 at 11:50 AM
💜 Don’t miss what’s next in Kotlin.
Get bite-sized updates, inspiration, and sneak peeks delivered right to your inbox.
Subscribe and stay in the loop 👉 https://kotl.in/news
📰 The new edition is coming soon!
Get bite-sized updates, inspiration, and sneak peeks delivered right to your inbox.
Subscribe and stay in the loop 👉 https://kotl.in/news
📰 The new edition is coming soon!
🚀 Dokka 2.1.0 is out!
This version focuses on stabilizing experimental features, supporting new Kotlin language updates, and improving the user experience.
🔗 Check out the details: https://github.com/Kotlin/dokka/releases/tag/v2.1.0
We'd really appreciate your feedback!
This version focuses on stabilizing experimental features, supporting new Kotlin language updates, and improving the user experience.
🔗 Check out the details: https://github.com/Kotlin/dokka/releases/tag/v2.1.0
We'd really appreciate your feedback!
October 17, 2025 at 2:07 PM
🚀 Dokka 2.1.0 is out!
This version focuses on stabilizing experimental features, supporting new Kotlin language updates, and improving the user experience.
🔗 Check out the details: https://github.com/Kotlin/dokka/releases/tag/v2.1.0
We'd really appreciate your feedback!
This version focuses on stabilizing experimental features, supporting new Kotlin language updates, and improving the user experience.
🔗 Check out the details: https://github.com/Kotlin/dokka/releases/tag/v2.1.0
We'd really appreciate your feedback!
📱 Two Years with Kotlin Multiplatform: From Zero to 55% Shared Code
At KotlinConf’25, @rsicarelli.bsky.social shared how StoneCo – serving 4M+ users – scaled KMP adoption, trained 130 engineers, and achieved 55% code sharing across two large-scale mobile apps.
📺 kotl.in/u5aa8v
At KotlinConf’25, @rsicarelli.bsky.social shared how StoneCo – serving 4M+ users – scaled KMP adoption, trained 130 engineers, and achieved 55% code sharing across two large-scale mobile apps.
📺 kotl.in/u5aa8v
September 27, 2025 at 8:52 AM
📱 Two Years with Kotlin Multiplatform: From Zero to 55% Shared Code
At KotlinConf’25, @rsicarelli.bsky.social shared how StoneCo – serving 4M+ users – scaled KMP adoption, trained 130 engineers, and achieved 55% code sharing across two large-scale mobile apps.
📺 kotl.in/u5aa8v
At KotlinConf’25, @rsicarelli.bsky.social shared how StoneCo – serving 4M+ users – scaled KMP adoption, trained 130 engineers, and achieved 55% code sharing across two large-scale mobile apps.
📺 kotl.in/u5aa8v
Do you have a complex business rule-set problem? Business rules spread across platforms, systems, and apps?
At KotlinConf’25, Anshika Koul shared how Norway’s 377-year-old national postal service tackled this challenge with Kotlin Multiplatform.
📺 kotl.in/v528cc
At KotlinConf’25, Anshika Koul shared how Norway’s 377-year-old national postal service tackled this challenge with Kotlin Multiplatform.
📺 kotl.in/v528cc
September 25, 2025 at 5:57 PM
Do you have a complex business rule-set problem? Business rules spread across platforms, systems, and apps?
At KotlinConf’25, Anshika Koul shared how Norway’s 377-year-old national postal service tackled this challenge with Kotlin Multiplatform.
📺 kotl.in/v528cc
At KotlinConf’25, Anshika Koul shared how Norway’s 377-year-old national postal service tackled this challenge with Kotlin Multiplatform.
📺 kotl.in/v528cc
🎉 Check out what's new on our Kotlin YouTube channel!
We’ve created a dedicated Kotlin Multiplatform playlist 📻 From quick tips and tutorials to KotlinConf KMP sessions, it’s your one-stop resource to learn and grow with KMP.
👉 Watch here: https://kotl.in/kmp-yt-play
We’ve created a dedicated Kotlin Multiplatform playlist 📻 From quick tips and tutorials to KotlinConf KMP sessions, it’s your one-stop resource to learn and grow with KMP.
👉 Watch here: https://kotl.in/kmp-yt-play
September 18, 2025 at 6:25 PM
🎉 Check out what's new on our Kotlin YouTube channel!
We’ve created a dedicated Kotlin Multiplatform playlist 📻 From quick tips and tutorials to KotlinConf KMP sessions, it’s your one-stop resource to learn and grow with KMP.
👉 Watch here: https://kotl.in/kmp-yt-play
We’ve created a dedicated Kotlin Multiplatform playlist 📻 From quick tips and tutorials to KotlinConf KMP sessions, it’s your one-stop resource to learn and grow with KMP.
👉 Watch here: https://kotl.in/kmp-yt-play
Want to publish your Kotlin Multiplatform library to the Maven Central repository but not sure where to start? 🔎 We've created a step-by-step tutorial on how to do it!
Check it out: 👉 https://kotl.in/9jwqoc
Check it out: 👉 https://kotl.in/9jwqoc
September 13, 2025 at 7:01 PM
Want to publish your Kotlin Multiplatform library to the Maven Central repository but not sure where to start? 🔎 We've created a step-by-step tutorial on how to do it!
Check it out: 👉 https://kotl.in/9jwqoc
Check it out: 👉 https://kotl.in/9jwqoc
🦸 Join Kotlin Heroes: Episode 13 today!
Sign up now for a chance to win a T-shirt and sharpen your Kotlin skills ⤵️
codeforces.com/contests/214...
Sign up now for a chance to win a T-shirt and sharpen your Kotlin skills ⤵️
codeforces.com/contests/214...
September 12, 2025 at 11:03 AM
🦸 Join Kotlin Heroes: Episode 13 today!
Sign up now for a chance to win a T-shirt and sharpen your Kotlin skills ⤵️
codeforces.com/contests/214...
Sign up now for a chance to win a T-shirt and sharpen your Kotlin skills ⤵️
codeforces.com/contests/214...
📦 Multiplatform Settings: A case study in Multiplatform library development
In this KotlinConf’25 talk, @russhwolf.com shares the story of how the library began, its early evolution, and where it’s headed – inspiring others to create their own.
📺 Watch now: kotl.in/jru1t2
In this KotlinConf’25 talk, @russhwolf.com shares the story of how the library began, its early evolution, and where it’s headed – inspiring others to create their own.
📺 Watch now: kotl.in/jru1t2
September 11, 2025 at 1:32 PM
📦 Multiplatform Settings: A case study in Multiplatform library development
In this KotlinConf’25 talk, @russhwolf.com shares the story of how the library began, its early evolution, and where it’s headed – inspiring others to create their own.
📺 Watch now: kotl.in/jru1t2
In this KotlinConf’25 talk, @russhwolf.com shares the story of how the library began, its early evolution, and where it’s headed – inspiring others to create their own.
📺 Watch now: kotl.in/jru1t2
✨ “One Codebase, Three Platforms: X’s Experience with Kotlin Multiplatform” – watch this KotlinConf'25 talk on the Kotlin YouTube channel.
Arkadii Ivanov and Eric Denman share their exciting story about rewriting X for Android and how they leveraged KMP to do it.
📺 Watch now: kotl.in/entz2y
Arkadii Ivanov and Eric Denman share their exciting story about rewriting X for Android and how they leveraged KMP to do it.
📺 Watch now: kotl.in/entz2y
September 6, 2025 at 7:13 AM
✨ “One Codebase, Three Platforms: X’s Experience with Kotlin Multiplatform” – watch this KotlinConf'25 talk on the Kotlin YouTube channel.
Arkadii Ivanov and Eric Denman share their exciting story about rewriting X for Android and how they leveraged KMP to do it.
📺 Watch now: kotl.in/entz2y
Arkadii Ivanov and Eric Denman share their exciting story about rewriting X for Android and how they leveraged KMP to do it.
📺 Watch now: kotl.in/entz2y
⏳ The Kotlin Developer Survey closes soon – don’t miss your chance to provide us with feedback that will help guide Kotlin’s evolution.
Just 10 minutes to share insights we truly value.
👉 kotl.in/dev-survey-25
Just 10 minutes to share insights we truly value.
👉 kotl.in/dev-survey-25
September 3, 2025 at 4:45 PM
⏳ The Kotlin Developer Survey closes soon – don’t miss your chance to provide us with feedback that will help guide Kotlin’s evolution.
Just 10 minutes to share insights we truly value.
👉 kotl.in/dev-survey-25
Just 10 minutes to share insights we truly value.
👉 kotl.in/dev-survey-25
We’re testing a landing page for a JetBrains product – and you can help shape it!
🎁 Everyone who completes the task with meaningful input gets a reward
🎥 You’ll need to record your screen and voice (desktop only)
👉 Start with a quick eligibility survey: https://jb.gg/21w94y
🎁 Everyone who completes the task with meaningful input gets a reward
🎥 You’ll need to record your screen and voice (desktop only)
👉 Start with a quick eligibility survey: https://jb.gg/21w94y
August 27, 2025 at 5:38 PM
We’re testing a landing page for a JetBrains product – and you can help shape it!
🎁 Everyone who completes the task with meaningful input gets a reward
🎥 You’ll need to record your screen and voice (desktop only)
👉 Start with a quick eligibility survey: https://jb.gg/21w94y
🎁 Everyone who completes the task with meaningful input gets a reward
🎥 You’ll need to record your screen and voice (desktop only)
👉 Start with a quick eligibility survey: https://jb.gg/21w94y
🔥 The last six months have been huge for Kotlin!
From major feature releases to stability milestones, we’ve achieved a lot together.
🚀 And the upcoming months are looking even more exciting! Check out our updated Kotlin roadmap to see what’s coming next.
👉 https://kotl.in/roadmap 👈
From major feature releases to stability milestones, we’ve achieved a lot together.
🚀 And the upcoming months are looking even more exciting! Check out our updated Kotlin roadmap to see what’s coming next.
👉 https://kotl.in/roadmap 👈
August 25, 2025 at 3:15 PM
🔥 The last six months have been huge for Kotlin!
From major feature releases to stability milestones, we’ve achieved a lot together.
🚀 And the upcoming months are looking even more exciting! Check out our updated Kotlin roadmap to see what’s coming next.
👉 https://kotl.in/roadmap 👈
From major feature releases to stability milestones, we’ve achieved a lot together.
🚀 And the upcoming months are looking even more exciting! Check out our updated Kotlin roadmap to see what’s coming next.
👉 https://kotl.in/roadmap 👈
🪄 Type aliases can make long type names shorter and generic names more domain-specific. In Kotlin 2.2, you can now define nested type aliases to make your code even more readable and maintainable.
📺 See how this works in our video: kotl.in/bbjqme
📺 See how this works in our video: kotl.in/bbjqme
August 22, 2025 at 2:07 PM
🪄 Type aliases can make long type names shorter and generic names more domain-specific. In Kotlin 2.2, you can now define nested type aliases to make your code even more readable and maintainable.
📺 See how this works in our video: kotl.in/bbjqme
📺 See how this works in our video: kotl.in/bbjqme