CodeCafé – A real-time collaborative code editor in the browser

In plain words

CodeCafé is a browser-based code editor that lets multiple users write and run code together in real time without downloads, sign-ups, or setup. Built with React and TypeScript on the frontend and Java Spring Boot on the backend, it uses WebSockets and a custom Operational Transformation system for real-time syncing. The tool is designed for educators and students who need a simple collaborative coding environment, inspired by the need for something better than using Google Docs for programming instruction.

written from the facts on this page · September 2026

From the sources

Browser-based real-time code editor with multiuser collaboration - mrktsm/codecafe

A browser-based real-time code editor with multiuser collaboration powered by operational transformation (OT). CodeCafé uses a custom OT implementation on both the client and server to keep all participants’ views of a document consistent. git clone https://github.com/mrktsm/codecafe.git cd codecafe docker-compose up Access the app at http://localhost:80 For more detailed setup and development guidelines, see CONTRIBUTING.md . Contributions are welcome. Please see CONTRIBUTING.md forfrom github.com

In the maker’s words, at launch

Hey guys! I’ve been working on a web app called CodeCafé—a collaborative, browser-based code editor inspired by VS Code and Replit, but with no downloads, no sign-up, and zero setup. You just open the link and start coding—together. The frontend is built with React and TypeScript, and the backend runs on Java with…

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