In this chapter, we will build a chat service with both a frontend and a backend. After completing the code, we will also walk through the process of deploying it using Docker. The project is structured as follows: multiple clients access the service through a web browser, and the backend serves the frontend web pages. From the frontend, users can chat with others in real time by communicating with the backend. Chats take place within rooms, and users can create or delete new rooms. Rooms and chat messages are stored in a database.