How Google Docs Uses Operational Transformation for Real-Time Collaboration

Real-time collaborative editing is one of the most complex and rewarding problems in distributed systems. Google Docs provides a near-instantaneous collaborative writing experience for users around the world — thanks to a technique called Operational Transformation (OT). But OT is just one of several automatic conflict resolution techniques discussed in Designing Data-Intensive Applications by Martin Kleppmann. In this blog, we’ll explain how OT works, compare it with other techniques like CRDTs and mergeable persistent data structures, and help you decide which to use for your application.

Apr 30, 2025 - 05:52

How Google Docs Uses Operational Transformation for Real-Time Collaboration

Real-time collaborative editing is one of the most complex and rewarding problems in distributed systems. Google Docs provides a near-instantaneous collaborative writing experience for users around the world — thanks to a technique called Operational Transformation (OT).

But OT is just one of several automatic conflict resolution techniques discussed in Designing Data-Intensive Applications by Martin Kleppmann. In this blog, we’ll explain how OT works, compare it with other techniques like CRDTs and mergeable persistent data structures, and help you decide which to use for your application.