Datomic

Datomic is a distributed database and implementation of Datalog. It has ACID transactions, joins, and a logical query language, Datalog. A distinguishing feature of Datomic is that time is a basic feature of data entities.

Architecture
It has been designed for first-class use with JVM languages such as Java and Clojure.

In its reference architecture, Datomic uses peers and transactors which run on the JVM.