This document summarizes a presentation about choosing between Java 11 and Kotlin for upgrading code. It highlights new features in Java 11 like switch statements and collection convenience methods. It also discusses the presenter's experience migrating code from Java to Kotlin by making stream operations and repository calls more readable. Reasons given to switch to Kotlin include regular updates, interoperability, less boilerplate, and safe programming. The document ends by outlining a migration plan and encouraging trying Kotlin in proof of concepts first.