Gremlin is a Turing-complete, graph-based programming language developed in Java 1.6+ for key/value-pair multi-relational graphs known as property graphs. Gremlin makes extensive use of the XPath 1.0 language to support complex graph traversals. This language has applications in the areas of graph query, analysis, and manipulation. Connectors exist for the following data management systems:

* TinkerGraph in-memory graph
* Neo4j graph database
* Sesame 2.0 compliant RDF stores
* MongoDB document database