Persistence Software

Persistence Software was founded in 1991 by Derek Henninger, Christopher Keene, and Richard Jensen in San Mateo, California.

The company started life as a spinoff from Lighthouse Design. As the original NeXTSTEP computer shipped with a relational database and Objective-C, Lighthouse engineers created a simple mapping utility called Exploder to store objects in a relational database.

The Persistence team worked with Stanford University's professors Gio Wiederhold and Arthur M Keller, who was the chief technical advisor, to extend the object-relational mapping technology by adding the concepts of mapping related objects.^[1]

Persistence created a series of products that integrated object-to-relational mapping, caching, and cache synchronization with automated cache management.^[2][3] The products were marketed under the names PowerTier, EdgExtend, and DirectAlert.^[4]

Sun Microsystems licensed the Persistence technology in 1998, which was later incorporated into the Enterprise JavaBeans standard.^[5]

In 2004, Progress Software bought Persistence for $16 million.^[6][7]

• PowerTier overview from ServerWatch.
• PowerTier 6 product review from Java Developer's Journal