Your e-commerce platform just crossed 2M daily active users. 70% are in the US, 30% in Europe.
Latency complaints are piling up from European users — 380ms average round-trip to your US-East region. Support tickets are up 40%. Black Friday is in 6 weeks.
Your infrastructure: single AWS us-east-1 region, RDS PostgreSQL (primary), Redis cache, 12 microservices behind an API Gateway.
You need to get European latency under 80ms. The engineering team is debating four approaches.
Here's your constraint: you cannot afford a full database rewrite, and you need this shipped before Black Friday.
