Design a Collaborative Editor (Google Docs)

Advanced · 27 min read · High-Level Design, Case Studies: Advanced

OT vs CRDTs, sessions, presence and persistence.

This is an Advanced lesson, part of Premium. What it covers:

• 1. Clarify the problem
• 2. Requirements
• 3. Capacity estimation
• 4. Why naive approaches fail
• 5. Approach A — Operational Transformation (OT)
• 6. Approach B — CRDTs
• 7. High-level design
• 8. Deep dives
• 9. Failure modes
• 10. Trade-offs summary
• 11. What interviewers look for
• Interview questions
• Practice
• Further reading

Previous: Design a Distributed Job Scheduler · Next: Design a Distributed Key-Value Store