Yjs

The leading open-source CRDT engine for building conflict-free collaborative data structures in JavaScript/TypeScript.

Overview

Yjs is a powerful, framework-agnostic library that implements CRDTs (Conflict-Free Replicated Data Types) like Y.Text, Y.Map, and Y.Array. It does not provide a server; instead, it connects to various awareness servers (like Y-Websocket or Liveblocks) to sync state across clients. It is the backbone of many major collaborative apps, offering deep integration with content-editable divs and rich text editors.

Best for

• Rich text editors
• Custom collaborative data structures
• Self-hosted collaboration infrastructure

Trade-offs

What XeroHack pre-wires

When you pick Yjs in the interview, the engine emits these files into your scaffold:

• Y.Doc initialization
• Awareness provider setup
• Y.Text binding to UI