Author Archives: Andrey Breslav

About Andrey Breslav

Andrey is the lead language designer working on Project Kotlin at JetBrains. He also works on making the Java language better, serving as a Java Community Process expert in a group for JSR-335 ("Project Lambda"), and occasionally speak at software conferences such as Devoxx or JavaOne.

Kotlin M5 is Out!

In two weeks from now it will be one year since Kotlin started out as an open source project. It’s been a lot of hard work over this time, with a huge help of the community: we received 164 pull … Continue reading

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Kotlin M4 is Out!

Today we roll out Kotlin M4 (from under snow). This post gives an overview of new features and other things this milestone brings.

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Dogfooding Kotlin and M3.1

After releasing Kotlin M3, we immediately started dogfooding Kotlin. Working on KAnnotator — a static analysis tool that will automatically infer nullability annotations for libraries — helps us tremendously at prioritizing issues. As a result, we roll out a bugfix … Continue reading

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Free Kotlin Webinar on Wednesday, October 10th

Join me (Andrey Breslav) and Hadi Hariri in a webinar about Kotlin M3. We will discuss the new features and our plans, give some demos and answer your questions. The free webinar will take place Wednesday, October 10th at 16:00 CET … Continue reading

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Kotlin M3 is Out!

Last time I wrote about a new exciting feature in “the upcoming Kotlin M3″. Today, Kotlin M3 is not “upcoming” any more, it’s here. This post gives an overview of the new milestone.

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How do you traverse a map?

It’s been a while since I blogged last time on Kotlin M2. Now, the hot summer has passed, and M3 will be out very soon. In this post I describe two small features added in M3 that make our lives … Continue reading

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Kotlin M2 is Out!

Some news websites told you that Kotlin M2 was out earlier this week. Well, now we make it come true In the M2 Candidate post I told you about JavaScript and Android support, as well as new Language Features. Now … Continue reading

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Kotlin M2 Candidate

It’s been seven weeks since Kotlin M1 release, and I’m happy to invite you to try out a candidate build of Kotlin M2! This post gives an overview of the upcoming milestone release along with come usage instructions. Thank you, … Continue reading

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Kotlin M1 is Out!

Today we are pleased to announce M1: the first milestone release of Kotlin. Kotlin’s homepage ( provides full details about the language. In this post I give some highlights associated with the milestone release. What’s in the box Kotlin comes … Continue reading

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Kotlin M1 Candidate

IntelliJ IDEA 11.1 has been recently released, and we are happy to announce a milestone candidate build for Kotlin IDE plugin, too. This post gives an overview of what happened over the last month. Milestone Candidate Build is Ready for … Continue reading

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