Problem context and objectives
Lead systems engineer · Open the Low-Level Workshop
Design the internals of a limited-stock reward redemption component. Define its API, domain state, persistence constraints, concurrency behavior, and testable responsibilities.
The design must survive campaign 100K rewards and burst 50K requests/s. 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
- campaign: 100K rewards
- burst: 50K requests/s
- Redeem once per player
- Never oversell inventory
Live architecture trace
Open the Low-Level Workshop: request to outcome
POST /redemptions sends “command + key” to Redeem handler. An LLD contract names inputs, outputs, validation, status or error types, authentication context, idempotency behavior, and compatibility expectations.
Design the internals of a limited-stock reward redemption component. Define its API, domain state, persistence constraints, concurrency behavior, and testable responsibilities. 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.