Notion redesigned its text editing system in 2025 to support true concurrent editing by implementing CRDTs (Conflict-free Replicated Data Types), replacing a "last write wins" approach that caused data loss when multiple users edited the same block simultaneously. The CRDT implementation uses a Replicated Growable Array structure where each character has a unique ID, allowing concurrent insertions and deletions to merge deterministically without losing changes.
Notion redesigned its text editing system in 2025 to support true collaborative editing by implementing CRDTs (Conflict-free Replicated Data Types), replacing the previous "last write wins" approach that caused users to lose concurrent edits. The CRDT implementation uses a Replicated Growable Array structure where each character has a unique ID, allowing simultaneous edits to be merged without data loss while preserving user intent in most cases.