We Ditched MongoDB for PostgreSQL 17: 3 Months of Production Postmortem After 10% Latency Spikes

Three months ago, our payment processing pipeline started throwing 10% latency spikes every 15 minutes. MongoDB 6.0’s aggregation-heavy workloads were choking on 12TB of transactional data, and after 72 hours of on-call firefighting, we made the call...