Take a closer look at the project named Reserve.http://squeaksource.com/REServe.htmlIt does most of what IOSPersistence does but is a cleaner design and supports PostgreSQL.IOSPersistence is a library for Squeak that automatically maps object to a database so they can be stored. No SQL or explicit directions are needed to be given to the class to tell it how to store its self in a database. It frees the programmer from the tedious task to creating tables and writing SQL but it comes with some mighty big limitations; there are a limited number of Objects it supports, a number of basic types and any subclass of IOSPersistence