Problem context and objectives
Lead systems engineer · The Requirements Compass
Design the first version of a live game leaderboard. Before drawing architecture, separate functional requirements from quality attributes and estimate the load that shapes the solution.
The design must survive players 5M daily and score writes 20K/s peak. 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
- players: 5M daily
- score writes: 20K/s peak
- Submit a score
- Read top 100
New words in this mission
Open a term for a plain-language explanation.p99 latency+
If 100 actions are measured, about 99 finish within this time. Teams use it to notice the experience of nearly the slowest users.
latency+
The waiting time from starting an action until its result is available. Lower latency makes interactions feel more immediate.
Live architecture trace
The Requirements Compass: request to outcome
Game server sends “verified score” to Score API. Functional requirements say what users can do. Non-functional requirements define qualities such as latency, availability, durability, consistency, security, cost, and scale.
Design the first version of a live game leaderboard. Before drawing architecture, separate functional requirements from quality attributes and estimate the load that shapes the solution. 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.