Abstract

Kotlin is a statically typed programming language for the JVM , Android and the browser. The language was conceived as a pragmatic tool for industry, and its main focus has been on interoperability, safety, flexibility and conciseness.

The project is Open Source and primarily backed by JetBrains, which is best known for its development tools such as IntelliJ IDEA and ReSharper.

This talk is focused on the challenges we faced while working on Kotlin, bigest of which fall into one of the two categories: interoperability concerns (for Java and JavaScript), and tooling (IDEs and build systems). We will talk about handling nulls through flexible types (a somewhat limited variation of gradual types), improving type-safety of collection interfaces without changing their implementations, making an IDE fast on questions that traditional compilers are not designed to answer, and, if time permits, challenges of incremental compilation.

Short bio: Andrey Breslav is the Lead Language Designer and Project Manager of Kotlin at JetBrains. He has been working on Kotlin since 2010. He also took part in designing lambdas for Java 8 as a member of a JSR Expert Group. Before joining JetBrains he did academic research on Domain-Specific Languages and static analysis and taught several courses to university students. He is a frequent speaker at major technology conferences, such as JavaOne and Devoxx.