Vespa

Vespa is an open-source big data serving engine developed by Yahoo that enables real-time computation over large datasets including vector search, structured search, and machine-learned ranking in a single horizontally scalable platform. It is used for applications requiring low-latency retrieval and ranking over billions of items with complex query-time computation, making it suitable for large-scale recommendation systems, news feed ranking, and enterprise search. Engineering teams at companies requiring sophisticated real-time search and recommendation at internet scale use Vespa for its unique combination of vector search, streaming computation, and horizontal scalability that single-purpose vector databases cannot match.