Today I released an implementation of akka persistence journal backed by FoundationDB: https://github.com/meln1k/akka-persistence-foundationdb
Some features you may find interesting:
Database push for live queries, it allows ~30ms lag between persisting the event and its appearance in read query stream.
Safe event insertion mode, if it’s enabled,
persistAsynccalls will return an exception if two writers will write an event with the same
sequenceNr. It should prevent the journal corruption in case of split brains.
Two ways to save your tags: a reference to an existing event or a whole copy of the existing event. It helps if you want to be flexible between the amount of used storage space and performance of your reads.
It’s possible to use a lot of tags per event. The plugin has been tested to work with 1000 tags per one event.