Earlier this month I attended the first KotlinConf organized by JetBrains, the creators of the language. It was located on Pier 27 in San Francisco, CA, overlooking the water. It was a great venue, with beautiful views to enjoy between sessions.

I learned so much from the variety of session available to attend. In addition to finding out what’s new in Kotlin, I now have a deeper understanding about type system after Huyen Tue Dao and Christina Lee’s talk “The Road to Kotlintown”, and Svetlana Isakova’s talk “Kotlin Types: Exposed”. Kevin Most gave some great tips on how to keep your Kotlin code idiomatic when interoping with Kotlin in his talk “Idiomatic Interop” as well.

Android is where I primarily use Kotlin, so there was much for me to learn about other uses of the language. In addition to the JVM, Kotlin also compiles down to JavaScript and Native. It was cool to see how it can be used on the server and iOS. There are some great improvements being made on how Kotlin code can be shared across platforms.

I was also a part of the speaker line up. Together with Boris Farber, I talked about the build pipeline of Kotlin on the JVM and the things we can learn from it. (Link to the video here) By inspecting the bytecode generated from the Kotlin compiler, we can gain insight into different Kotlin language features, as well as performance and size implications that can be used to make trade off decisions.

Our talk paired nicely with Duncan McGregor’s talk “The Cost of Kotlin Language Features” that was given later on in the conference. In it he benchmarks some language features in both Java and Kotlin to see if there are any performance implications. Although Kotlin seems to favor safety and predicability over raw performance, there does not seem to be any glaring issues you should be worried about when using Kotlin over Java.

The conference wasn’t without its entertainment as well. The night before the conference I joined the rest of the speakers on a dinner cruise around the bay. It was breathtaking to see the Bay Bridge and Golden Gate Bridge lit up under the night sky. The first day of the conference was also closed out by a magic show by developer turned magician, Michael Carducci. He had the entire audience in amazement with his performance.

Sold out with 1200 in attendance, and such smooth sailing throughout the event, I would consider this first Kotlin conference a success. I’m looking forward to the next one.

Here’s the complete list of videos for the talks I mentioned above

• The Road to Kotlintown by Huyen Tue Dao and Christina Lee
• Kotlin Types: Exposed by Svetlana Isakova
• Idiomatic Interop by Kevin Most
• The Cost of Kotlin Language Features by Duncan McGregor