Cayley is a graph database and query engine designed to store and retrieve interconnected data. It functions as a quad store, persisting information as four-element tuples to maintain complex relationships and semantic linked data.
The system features a backend-agnostic storage layer that decouples the graph API from the underlying data store. This allows for the integration of external backends through a modular adapter system, enabling the synchronization of data across different storage engines.
The project provides a pattern-matching query engine for extracting specific nodes and relationships. It also includes a built-in visual editor for graph exploration and the mapping of data connections.