Dave Leeds
@typealias.com
I write and draw cartoons about #Kotlin at http://typealias.com
Concurrency + Mutable State = Risk
Kotlin's design of coroutines prevents a lot of problems, but not race conditions. It does give us some great tools to help, though! Here's a 9-minute video that covers what you need to know about each one. I hope you find it helpful!
👉 youtu.be/Ap-cVIM5ORY
Kotlin's design of coroutines prevents a lot of problems, but not race conditions. It does give us some great tools to help, though! Here's a 9-minute video that covers what you need to know about each one. I hope you find it helpful!
👉 youtu.be/Ap-cVIM5ORY
How to Prevent Race Conditions in Kotlin Coroutines
YouTube video by Dave Leeds
youtu.be
November 24, 2025 at 3:50 PM
Concurrency + Mutable State = Risk
Kotlin's design of coroutines prevents a lot of problems, but not race conditions. It does give us some great tools to help, though! Here's a 9-minute video that covers what you need to know about each one. I hope you find it helpful!
👉 youtu.be/Ap-cVIM5ORY
Kotlin's design of coroutines prevents a lot of problems, but not race conditions. It does give us some great tools to help, though! Here's a 9-minute video that covers what you need to know about each one. I hope you find it helpful!
👉 youtu.be/Ap-cVIM5ORY
I can't wait to start up the livestreams again! We're kicking off the fall season this Wednesday at 10 AM CDT with special guest Kevin Tang, who's going to show us what Firebender can do!
typea.li/as/live08
Add to your calendar:
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typea.li/as/live08
Add to your calendar:
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Firebender - TypeAlias Show #8
We're kicking off the fall season with special guest Kevin Tang, who's going to show us what Firebender can do.
In this episode, we will:
- Check out some of the latest roadmap updates for Kotlin.
- ...
typea.li
September 8, 2025 at 2:24 PM
I can't wait to start up the livestreams again! We're kicking off the fall season this Wednesday at 10 AM CDT with special guest Kevin Tang, who's going to show us what Firebender can do!
typea.li/as/live08
Add to your calendar:
Google - typea.li/as/vvcxd6l
Download Invite - typea.li/as/8lxgxw2
typea.li/as/live08
Add to your calendar:
Google - typea.li/as/vvcxd6l
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Need to put those #Kotlin flows together? The merge(), combine(), and zip() functions are available, and each one works a little differently - I break them down for you in this video.
youtu.be/Jmwr9vcmWWs
youtu.be/Jmwr9vcmWWs
Putting Kotlin Flows Together
YouTube video by Dave Leeds
youtu.be
September 5, 2025 at 1:57 PM
Need to put those #Kotlin flows together? The merge(), combine(), and zip() functions are available, and each one works a little differently - I break them down for you in this video.
youtu.be/Jmwr9vcmWWs
youtu.be/Jmwr9vcmWWs
Wow, that's a lot of growth in one year! 🎉
🔥 Nearly 1 in 5 use Kotlin Multiplatform for their cross-platform projects!
📈 According to the last two Developer Ecosystem Surveys, its usage grew from 7% in 2024 to 18% in 2025.
kotl.in/deveco-24
📈 According to the last two Developer Ecosystem Surveys, its usage grew from 7% in 2024 to 18% in 2025.
kotl.in/deveco-24
August 14, 2025 at 6:23 PM
Wow, that's a lot of growth in one year! 🎉
It's been a few years since I've worked on a Spring service, but the new Spring Debugger plugin in the latest @intellijidea.com looks really cool! Stuff like...
- Loaded vs unloaded beans
- Active vs inactive configs
- Debug beans at use site
More about 2025.2: www.jetbrains.com/idea/whatsnew/
- Loaded vs unloaded beans
- Active vs inactive configs
- Debug beans at use site
More about 2025.2: www.jetbrains.com/idea/whatsnew/
What's New in IntelliJ IDEA
Explore IntelliJ IDEA's latest features and updates to elevate your professional Java and Kotlin development experience.
www.jetbrains.com
August 7, 2025 at 1:17 PM
It's been a few years since I've worked on a Spring service, but the new Spring Debugger plugin in the latest @intellijidea.com looks really cool! Stuff like...
- Loaded vs unloaded beans
- Active vs inactive configs
- Debug beans at use site
More about 2025.2: www.jetbrains.com/idea/whatsnew/
- Loaded vs unloaded beans
- Active vs inactive configs
- Debug beans at use site
More about 2025.2: www.jetbrains.com/idea/whatsnew/
Hey, Valère! Thanks for asking! My video editing is done in Davinci Resolve. Some of the annotations (basic lines and circles) are just my own hand-drawn annotations, but the ones that zoom in like that are plugins from MotionVFX. I believe the one in your screen grab is from mHowTo.
August 4, 2025 at 3:21 PM
Hey, Valère! Thanks for asking! My video editing is done in Davinci Resolve. Some of the annotations (basic lines and circles) are just my own hand-drawn annotations, but the ones that zoom in like that are plugins from MotionVFX. I believe the one in your screen grab is from mHowTo.
Reposted by Dave Leeds
🎟️ Super Early Bird tickets for KotlinConf 2026 are live!
🗺️ We’re heading to Munich, Germany – a brand-new venue in the heart of Europe.
Secure your spot now 👉 kotl.in/conf26-tickets
🗺️ We’re heading to Munich, Germany – a brand-new venue in the heart of Europe.
Secure your spot now 👉 kotl.in/conf26-tickets
Registration | 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
July 22, 2025 at 10:52 AM
🎟️ Super Early Bird tickets for KotlinConf 2026 are live!
🗺️ We’re heading to Munich, Germany – a brand-new venue in the heart of Europe.
Secure your spot now 👉 kotl.in/conf26-tickets
🗺️ We’re heading to Munich, Germany – a brand-new venue in the heart of Europe.
Secure your spot now 👉 kotl.in/conf26-tickets
Reposted by Dave Leeds
📨 Want exclusive KotlinConf news before everyone else?
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Subscribe to the KotlinConf newsletter 👉 kotlinconf.com/subscription/
Newsletter subscribers get early access to the Super Early Bird and Early Bird ticket launches, key dates, and more.
Subscribe to the KotlinConf newsletter 👉 kotlinconf.com/subscription/
July 14, 2025 at 5:04 PM
📨 Want exclusive KotlinConf news before everyone else?
Newsletter subscribers get early access to the Super Early Bird and Early Bird ticket launches, key dates, and more.
Subscribe to the KotlinConf newsletter 👉 kotlinconf.com/subscription/
Newsletter subscribers get early access to the Super Early Bird and Early Bird ticket launches, key dates, and more.
Subscribe to the KotlinConf newsletter 👉 kotlinconf.com/subscription/
Yeah!! We got to be partners for #KotlinConf this year! 🎉
May 25, 2025 at 4:29 PM
Yeah!! We got to be partners for #KotlinConf this year! 🎉
Yeah! I thought it was funny that this photo made a brief appearance in your presentation when you clicked over to the notifications page. 😅
May 23, 2025 at 5:16 PM
Yeah! I thought it was funny that this photo made a brief appearance in your presentation when you clicked over to the notifications page. 😅
Building a Bluesky Bot powered by AI at #KotlinConf, by @raphaeldelio.dev
May 23, 2025 at 2:20 PM
Building a Bluesky Bot powered by AI at #KotlinConf, by @raphaeldelio.dev
Ah, there ya go, that would do it! 😄
May 18, 2025 at 3:15 PM
Ah, there ya go, that would do it! 😄
I'm not on my usual Windows machine here, but on Mac I get the println() output regardless of the dispatcher I choose.
May 17, 2025 at 8:48 PM
I'm not on my usual Windows machine here, but on Mac I get the println() output regardless of the dispatcher I choose.
Thanks for looking into it! For what it's worth, I'm using Windows here, and Ctrl+C copies just the selection for me.
May 14, 2025 at 5:50 PM
Thanks for looking into it! For what it's worth, I'm using Windows here, and Ctrl+C copies just the selection for me.
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What can we do with Kotlin Notebooks? - TypeAlias Show #7
Google I/O and KotlinConf are just around the corner! Let's get one more livestream in before then!
- We'll check out the latest news happening in the Kotlin and Android worlds.
- We'll look over som...
typea.li
May 12, 2025 at 4:42 PM
You can add it to your calendar here:
Google Calendar - typea.li/as/by6y4dm
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So many exciting announcements in the #Kotlin and #AndroidDev worlds, even ahead of KotlinConf and Google I/O! Let's dig into them during this week's livestream. Plus, we'll check out lots of cool things we can do with Kotlin Notebooks. Wednesday 10 AM CDT. typea.li/as/live07
What can we do with Kotlin Notebooks? - TypeAlias Show #7
Google I/O and KotlinConf are just around the corner! Let's get one more livestream in before then!
- We'll check out the latest news happening in the Kotlin and Android worlds.
- We'll look over som...
typea.li
May 12, 2025 at 4:42 PM
So many exciting announcements in the #Kotlin and #AndroidDev worlds, even ahead of KotlinConf and Google I/O! Let's dig into them during this week's livestream. Plus, we'll check out lots of cool things we can do with Kotlin Notebooks. Wednesday 10 AM CDT. typea.li/as/live07
Double dispatch - let's see what it is, how it's traditionally handled in single-dispatch languages, and how we can get a similar effect in #Kotlin. www.youtube.com/watch?v=4cUQ...
Double Dispatch: Prelude to the Visitor Pattern
YouTube video by Dave Leeds
www.youtube.com
April 23, 2025 at 3:01 PM
Double dispatch - let's see what it is, how it's traditionally handled in single-dispatch languages, and how we can get a similar effect in #Kotlin. www.youtube.com/watch?v=4cUQ...
This Wednesday's #Kotlin video is about Double Dispatch - gotta understand it before we get to the Visitor Pattern!
Premieres this Wednesday:
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April 21, 2025 at 2:34 PM
This Wednesday's #Kotlin video is about Double Dispatch - gotta understand it before we get to the Visitor Pattern!
Premieres this Wednesday:
typea.li/as/x9lrbng
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#Kotlin Notebooks - Now included in IntelliJ IDEA Community Edition! 🎉https://blog.jetbrains.com/idea/2025/04/kotlin-notebook-arrives-in-intellij-idea/
April 18, 2025 at 4:46 PM
#Kotlin Notebooks - Now included in IntelliJ IDEA Community Edition! 🎉https://blog.jetbrains.com/idea/2025/04/kotlin-notebook-arrives-in-intellij-idea/
JetBrains' Junie AI coding agent has been promoted to general availability. No need to hang out on a waitlist any more! www.jetbrains.com/junie/
Junie, the coding agent by JetBrains
Delegate your tasks, focus on the results
www.jetbrains.com
April 16, 2025 at 8:03 PM
JetBrains' Junie AI coding agent has been promoted to general availability. No need to hang out on a waitlist any more! www.jetbrains.com/junie/
Thanks so much, Maxime! I hope you enjoy it!
April 11, 2025 at 2:59 AM
Thanks so much, Maxime! I hope you enjoy it!
Hey, it's a big day! After over 5 years of writing, illustrating, and updating, Kotlin: An Illustrated Guide is finally available in paperback!
amazon.com/Kotlin-Illus...
Thanks so much to all of you in the #Kotlin community for all the encouragement every step along the way! 🎉
amazon.com/Kotlin-Illus...
Thanks so much to all of you in the #Kotlin community for all the encouragement every step along the way! 🎉
Kotlin: An Illustrated Guide
Kotlin: An Illustrated Guide [Leeds, Dave] on Amazon.com. *FREE* shipping on qualifying offers. Kotlin: An Illustrated Guide
amazon.com
April 8, 2025 at 2:48 PM
Hey, it's a big day! After over 5 years of writing, illustrating, and updating, Kotlin: An Illustrated Guide is finally available in paperback!
amazon.com/Kotlin-Illus...
Thanks so much to all of you in the #Kotlin community for all the encouragement every step along the way! 🎉
amazon.com/Kotlin-Illus...
Thanks so much to all of you in the #Kotlin community for all the encouragement every step along the way! 🎉
What's new in Kotlin 2.1.20? During this Wednesday's livestream, we'll take a look at the new atomic types, some UUID updates, datetime changes, and lots more!
typea.li/as/live06
Google Calendar - typea.li/as/4xrb3gm
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typea.li/as/live06
Google Calendar - typea.li/as/4xrb3gm
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Kotlin 2.1.20 - Atomics, UUIDs, and more! - TypeAlias Show #6
YouTube video by Dave Leeds
www.youtube.com
April 7, 2025 at 3:17 PM
What's new in Kotlin 2.1.20? During this Wednesday's livestream, we'll take a look at the new atomic types, some UUID updates, datetime changes, and lots more!
typea.li/as/live06
Google Calendar - typea.li/as/4xrb3gm
Outlook Web - typea.li/as/zjdkbjs
Download Invite - typea.li/as/chnz9lp
typea.li/as/live06
Google Calendar - typea.li/as/4xrb3gm
Outlook Web - typea.li/as/zjdkbjs
Download Invite - typea.li/as/chnz9lp
For those who grew up in Jacobean England, reading modern English can be confusing with its shorter sentences and less eloquent phrasing. So today I'm releasing the first chapter of #Kotlin: An Illustrated Guide in Shakespearean English!
typealias.com/fun/illustra...
typealias.com/fun/illustra...
Of Variables, Expressions, and the Nature of Types
So thou seekest to be a Kotlin craftsman? Thou hast come unto the right place! Thy journey beginneth here in Chapter the First, wherein thou shalt learn of variables, expressions, and types.
typealias.com
April 1, 2025 at 7:04 PM
For those who grew up in Jacobean England, reading modern English can be confusing with its shorter sentences and less eloquent phrasing. So today I'm releasing the first chapter of #Kotlin: An Illustrated Guide in Shakespearean English!
typealias.com/fun/illustra...
typealias.com/fun/illustra...
Applying the Observer Pattern in Kotlin - premieres Wednesday at 10 AM CDT. See you there!
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March 24, 2025 at 2:26 PM
Applying the Observer Pattern in Kotlin - premieres Wednesday at 10 AM CDT. See you there!
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