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Problem Understanding
Restate the problem in your own words.
Design Google Docs (Real-time Collaboration)
Design a Google-Docs-class collaborative editor: multiple users edit the same document simultaneously, every keystroke converges across clients within ~150 ms, offline edits merge cleanly when a client reconnects, and the audit trail / version history is preserved. The hard parts are the OT (Operational Transform) or CRDT conflict-resolution algorithm, the WebSocket gateway scaling to millions of open docs, and undo semantics that survive network partitions.
- Google DocsThe canonical multi-user editor — OT-based, integrates with Drive for storage + permissions.
- Microsoft Word OnlineOffice’s real-time collab; combines OT for text with custom merge for layout.
- NotionBlock-based document model with CRDT semantics; the canonical ‘modern’ collab app.
- FigmaMulti-user vector editor — same problem on shapes + layers, much higher op rate.
Your task: read the problem above, then write what the system is, who uses it, the rough scale, and the headline UX expectation — in your own words. Submit for AI review when you're ready.
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