# Yjs
URL: https://wwadd.dev/tools/yjs · Official site: https://yjs.dev
Kind: CRDT library for shared data · License: Open source · Last verified: 2026-09-28

Represents shared documents as CRDTs, so edits from any number of clients merge automatically without conflicts or a central lock. Providers sync it over WebSockets, WebRTC, or IndexedDB for offline use.

Reach for it when:
- Real-time collaborative editors and whiteboards
- Apps where offline edits must merge cleanly later

Worth knowing: Store the binary Yjs state as the source of truth — rebuilding a document from rendered HTML or JSON loses the history offline edits need to merge.

Repository: https://github.com/yjs/yjs
Recorded SPDX baseline: NOASSERTION