This challenge builds on Cake Shop 3 - Going International. Complete it first for the best experience.
Sweet Crumbs Bakery now operates at massive scale. Maya wants two new capabilities:
1. Real-time order tracking - customers see live updates as their order moves through preparation, baking, quality check, packaging, and delivery. Kitchen staff use a live dashboard that updates instantly when new orders arrive.
2. Disaster resilience - the system must survive an entire cloud region going offline without losing orders or causing more than 30 seconds of customer-facing downtime.
This requires designing a real-time event pipeline, a WebSocket layer for push updates, and a multi-region failover strategy with data consistency guarantees.
Add real-time order tracking, kitchen displays, and survive an entire region going down. Build this architecture under realistic production constraints, then validate tradeoffs in the design lab simulation.
Clarify requirements: The monolith is getting hard to maintain. Teams want to deploy independently. Identify natural seams: product catalog, inventory, orders, payments, users.
Estimate scale: 1M+ DAU. Individual services need to scale independently -- the product catalog service gets 100x more reads than the payment service.
Pick components:
Key tradeoffs to discuss: