[FoundationDB](https://www.foundationdb.org/)is a distributed, transactional Key/Value database. It is maintained by Apple and powers the majority of Apple iOS applications. FoundationDB is the base or Foundation for a distributed database. In the majority of cases it would never be used stand alone but instead there would be layers built on top of it to build out a fully functional database. The Record Layer ([Paper](https://www.foundationdb.org/files/record-layer-paper.pdf) and [Code](https://github.com/FoundationDB/fdb-record-layer)) is an example of a layer built on top of FoundationDB that gives extra functionality closer to a fully functioning database. ## Good Articles and Papers 1. [Introducing Husky, Datadog's Third-Generation Event Store](https://www.datadoghq.com/blog/engineering/introducing-husky/) 2. [QuiCK: A Queuing System in CloudKit](https://www.foundationdb.org/files/QuiCK.pdf) 3. [Awesome FoundationDB](https://github.com/FoundationDB/awesome-foundationdb)