Fabrice Estiévenart is addicted to web and open-source technologies with a specific focus on web frameworks (Symfony, Pylons, Ruby on Rails), search engines (Lucene, Sphinx, Nutch, Solr), and database modelisation/abstraction (Doctrine, SQLAlchemy, Active Record). His favorite programming languages are PHP, Python, and Ruby.

He has initiated or contributed to several open-source projects such as SimPic (a lightweight PHP photo gallery), DocAlchemy (a 'Doctrine to SQLAlchemy' converter), DocRails (a 'Doctrine to Active Record' converter), CatCash (a rule-based transaction classifier in GnuCash) and Retroweb (a visual web-wrapping application).

Besides these initiatives, he is the developer and webmaster of several different web sites ranging from musical news portals (http://www.guitareacoustique.com) to personal blogs (http://www.destinationlibre.org, http://www.fabrisss.com).

Christian Stimming lives in Hamburg, Germany, working with SICK AG on research and C++ software development of real-time signal processing for industrial and automotive sensor applications. He learnt the benefits of Open Source software during his studies in Electrical Engineering at Hamburg University in the 1990s, started to contribute to the GnuCash project in 2000, and has been working with the GnuCash developer team since that time. Recently, he started a consulting business for users of GnuCash, successfully offering customization and training for small and home-office business customers in Germany. While reviewing this remarkably helpful book, his third child was born and Christian is happy to report all is well with his family and the new-born daughter in Hamburg.