Problem context and objectives
Mission briefing
Lead systems engineer · Conversation Ledger
Design storage for a multi-device chat service with ordered conversation history, unread counts, and message edits.
The design must survive messages 2M/s peak and history years. Every box must earn its place by satisfying a requirement or containing a failure.
How you win
- 1Trace one user action from request to durable outcome
- 2Connect every component to a stated requirement
- 3Explain the losing tradeoff, not only the chosen technology
Rules and pressure
- messages: 2M/s peak
- history: years
- Conversation ordering
- Cursor pagination
Lesson 1 of 3
Live architecture trace
Conversation Ledger: request to outcome
LIVE EVENTsocket
Chat clients sends “socket” to Realtime gateway. Partitioning by conversation and sorting by a server sequence matches ordered, cursor-based history reads.
messages = 2M/s peak
Design storage for a multi-device chat service with ordered conversation history, unread counts, and message edits. Follow one real user action through the complete architecture; a component is useful only when you can explain the request, state, or failure it handles.