Why One Team Ditched Four Databases and Consolidated Everything on Postgres

A development team that once ran MongoDB, Redis, Elasticsearch, and a vector database simultaneously has migrated entirely to PostgreSQL, citing unsustainable operational complexity. Each separate data store required its own backup strategy, scaling approach, and monitoring, often triggering independent failures in the middle of the night. The team also identified a problem they called the 'Retrieval Gap,' where reading from multiple stores simultaneously means each read reflects a different point in time, creating a composite data state that never truly existed. Modern Postgres extensions now cover vector search, message queuing, and durable workflow execution, making specialized databases largely redundant for many use cases. The consolidation reduced both cloud costs and operational overhead significantly, while ensuring all data reads reflect a consistent, single point in time.