DataNucleus Access Platform is an open source java persistence system, fully implementing and fully-compliant with the JDO1, JDO2+ and JPA1 specifications. It supports persistence to many types of datastores including RDBMS, ODBMS, XML, Excel/ODF, JSON, BigTable. This project is DataNucleus "core" providing the persistence framework used by all DataNucleus sub-projects (plugins). It includes transaction handling, logging, and management of datastores, together with the basis for JDOQL/JPQL querying.

Support for this persistence layer is provided by way of a Free Forum (no guarantee of availability) or via Commercial Support from DataNucleus.