OpenPSA is based on the Midgard Component Framework, and can be configured to use many of it's libraries. These provide services such as:
- Style Engine to easily customize OpenPSA's appearance to match CI guidelines
- Internationalization framework for creating localized output
- RCS-based version history of all main database objects
- Fulltext site-wide search with Lucene
- Automated server-to-server replication
- Administrative interface for low-level access
Furthermore, over 100 ready-made components are available that can be combined with OpenPSA's core feature set. You can find an overview on this wiki page.