Route Changes

18 December 2021

When we wrote the book, the latest Kotlin version was 1.4. The Kotlin team released version 1.5 just as we went to print. Now the Kotlin team have released 1.6 and started announcing features that will be in 1.7.

The underlying design principles we describe in the book don’t depend on any version of the language (or even on Kotlin itself). However, the details of some code examples and refactoring sequences will become outdated as the language and tooling evolves. We’ve created a section of this site, entitled “Route Changes”, that documents how the journeys in the book are affected — usually improved — by new versions of the language.