LogCabin is a distributed storage system built on Raft that provides a small amount of highly replicated, consistent storage. It is a reliable place for other distributed systems to store their core metadata and is helpful in solving cluster management issues.
Redis is an in-memory database that persists on disk. The data model is key-value, but many different kind of values are supported: Strings, Lists, Sets, Sorted Sets, Hashes, Streams, HyperLogLogs, Bitmaps.
A distributed, fast open-source graph database featuring horizontal scalability and high availability
The RaftLib C++ library, streaming/dataflow concurrency via C++ iostream-like operators