A realtime collaborative rich-text editor using Conflict-free Replicated Data Types (CRDTs) and Google's WebRTC framework. With this editor, several users can edit documents together in realtime with automatic conflict-merge and user-intent preservation. The implementation of the CRDT is using a variant of the RGA (Replicated Growable Arrays) protocol. The RGA protocol is implemented as Timestamped Insertion List (TI List) and guarantees "Eventual Consistency".
For more details about the CRDT implementation, see the documentation
- Real-time collaborative editing.
- Local-first software implementation.
- Automatic merge conflict resolution using CRDTs.
- User-intent preservation, drawing inspiration from Peritext.
- Peer to peer architecture using WebRTC.
It is recommended to have node and npm installed. This project was built using node version 20.11.1 and npm version 10.5.1.
Install the backend and frontend dependencies by running npm install inside the backend and frontend folders respectively.
Run the following command to check the code against all the available test cases
npm run --prefix backend test
The project can be run in three steps by running the below commands in the root directory:
- Run the backend file store server. This server interacts with the local store/filesystem for storing the CRDT. It also supports retrieval from the store.
npm run --prefix backend fileserver
- In a separate terminal, run the signaling server for WebRTC
npm run --prefix backend sigserver
- In a separate terminal, start the frontend app
npm run --prefix frontend start
Now, open two browser tabs to the address localhost:3000. These editors are now connected via a peer-to-peer network through WebRTC and can exchange local editor operations using WebRTC's data channel.
Usage is provided under the MIT License. See LICENSE for the full details.