Source code for the Javalin real-time collaboration tutorial, demonstrating how to build a collaborative editing application using the Javalin web framework. The project includes examples in both Kotlin and Java, accompanying the official Javalin tutorials for real-time collaboration. It shows how to set up WebSocket connections, synchronize document changes between multiple users, and handle concurrent edits in a lightweight web server environment. The example serves as a practical reference for developers learning to implement live, multi-user collaborative features such as shared documents or whiteboards using Javalin's real-time capabilities.