java.evolved is a community site that documents how common Java coding patterns have changed across language versions using side-by-side before/after examples. It targets developers working in mixed-era codebases (Java 6, 8, 17+) by showing how existing code would look if written with modern idioms. Examples include replacing verbose data classes with records, using pattern matching in instanceof checks, and leveraging switch expressions. The project is positioned as a practical reference for onboarding and code reviews in mature Java systems.