McObject's hybrid eXtremeDB Fusion combines on-disk and in-memory data storage in a single database system. Through a simple notation in the database design (schema), record types can be designated for persistent storage, while other records are stored in RAM. With this tool, developers can optimize applications for speed and persistence, while adopting the most cost-effective and physical space-conserving storage. eXtremeDB Fusion enables use of a single database system across embedded device product families in which some units include persistent storage, while others don't. This results in significant engineering cost and time savings.