HyperGraphDB is a general purpose, extensible, portable, distributed, embeddable data storage mechanism. Designed specifically for artificial intelligence and semantic web projects, it can also be used as an embedded object-oriented database for projects of all sizes. It is a Java-based product built on top of the Berkeley DB storage library. It can be used as a single in-process database bound to a location on the local disk or within a "cloud" of networked database instances communicating and sharing data in a P2P (peer-to-peer) fashion. Key features include storage of generalized hypergraphs, an open, extensible type system, basic query system and graph traversal algorithms, out-of-the-box support for Java object storage, thread-safe transactions, and a P2P framework for data distribution.
Bitsy is a small, fast, embeddable, durable in-memory graph database that implements the Blueprints API. It is an ACID database that recovers cleanly from power failures and crashes. Designed for multi-threaded OLTP applications, Bitsy implements optimistic concurrency control and stores data in human-readable JSON-encoded text files. Common management tasks such as online backups can be done over JMX. The speed and simplicity of Bitsy relies on three design principles: No Seek, No Socket, NoSQL.
Pixy is a declarative graph query language that works on any Blueprints-compatible graph database. The Blueprints API provides a common interface to over a dozen graph databases, including Neo4J, Titan, Infinite Graph, OrientDB, DEX, and Bitsy. Pixy enables complex pattern matching and logic programming on graph databases by translating PROLOG-style rules and goals to Gremlin pipelines that represent graph traversal operations. Queries in Pixy can also be seemlessly integrated into Gremlin expressions. The combination of Pixy and Gremlin gives the programmer the full power of two graph querying paradigms, viz. graph pattern matching and graph traversal.