Paul Courbis (born 3 November 1967), is a French programmer, mostly known for reverse engineering the HP-28 and then the HP 48 series of calculators, and writing multiple articles and books disclosing his findings. These books had a surprising success in France. Paul Courbis is the chief information officer at the French , he is also working during his spare time on a set of tools to help people administrating Alcatel's PABX (for the 4400 series). He also publishes various tricks (iPhone, shells scripts, etc.) on his web site.