The open big data serving engine: Store, search, rank and organize big data at user serving time.
Started as a web search engine (1997) - alltheweb.com. Acquired by Yahoo! and generalized to handle general big data serving use cases (search recommendation etc.).
https://vespa.ai/
https://github.com/vespa-engine/vespa
https://docs.vespa.ai
Yahoo!
NO
Open Source
C++
Java
Linux
Apache v2