Stein Erik Ellevseth is a retired computer scientist with background as software developer, researcher and consultant. His area of interest is software development of telecommunication and control system, modeling, process improvement. At Alcatel STK/Telecom (1980 - 1998) he took part in development of the Nodal Switch System and Multi Role radio, at Ericsson NorARC and CSDS (1998 - 2002) he worked with SDL adoption within Ericsson and Circuit Switched Data Services, at Kongsberg Devotek (2002 - 2009) he was an and ABB Corporate Research (2010 - 2015) he was an internal consultant of code generation support of Matlab Simulink. He is an early adopter of SDL (Z.100) and code generation from SDL to CHILL (Z.200). From 1989 - 1996 he was engaged as representative from Alcatel Telecom in the SISU project.