It really wasn't. FoundationDB's USP was transactions. Cassandra was designed as a AP system, and using it as a strongly consistent system came at great latency

It really wasn't. FoundationDB's USP was transactions. Cassandra was designed as a AP system, and using it as a strongly consistent system came at great latency costs. In addition, atomicity outside of a row was all but impossible. Features such as lightweight transactions tried to remedy that, slightly, but suffered from poor performance (was basically just bolting on paxos using the Cassandra protocol, as I under stand it), and correctness problems (see aphyr's post on Cassandra). FoundationDB, on the other hand, was designed from the ground up to support transactions. Features such as MVCC, multi key (read: multi-machine) transactions, all while providing a sane-ish datamodel and very good performance... well boy oh boy they had some real potential. And now they have been subsumed by Apple. "and they were never heard from again" EDIT: a while back I commented on a comparison of FoundationDB to Cassandra, and Dave Rosenthal, the FoundationDB CEO, took the time to respond. I completely disagreed with him at the time, but think I understand his points now. Link: http://news.ycombinator.com/item?id=8745462 http://news.ycombinator.com/item?id=8745462