Simulation run on this device. Scenario values are not sent anywhere — the engine is fully local.
system design game · free
Multi-Region Failover Game
Play the incident — drain, promote, and watch RTO tick down.
Can you fail over before the error budget burns?
Engine 1.0.0 · game
ms
20400
s
160
s
1300
s
060
- RTO (est.)
- 70 s
- RPO (async)
- 5 s
- User-visible stall
- 70 s
- Cross-region tax
- 120 ms
Lower detect+DNS to cut RTO; sync replication cuts RPO at latency cost.
detect 10s + dns 60s
Method
- Deterministic local model of the mechanism — knobs recompute outputs instantly with no network.
- Numbers are teaching approximations, not production capacity guarantees.