In 1980 he started at Bell Labs in Murray Hill for a year. Back in the Netherlands he was assistant professor at the Delft University of Technology for two years.[2] In 1983 he returned to Bell Labs where he worked in the Computing Science Research Center (the former Unix research group). In 2003 he joined NASA, where he leads the NASA JPLLaboratory for Reliable Software[3] in Pasadena, California and is a JPL fellow.[1]
Holzmann is known for the development of the SPIN model checker (SPIN is short for Simple Promela Interpreter) in the 1980s at Bell Labs. This device can verify the correctness of concurrent software, since 1991 freely available.
^ abHolzmann, Gerard J. "The Pandora System: an interactive system for the design of data communication protocols." Computer Networks (1976) 8.2 (1984): 71-79.