Management Team

Steve Sims

Chief Executive Officer

Steve Sims is CEO and a co-founder of Reactive Systems, Inc. He is a co-author of the initial version of the company's flagship Reactis product and continues to lead its development. Sims enjoys working closely with RSI's customers to ensure that the company's offerings exceed their expectations.

Prior to the inception of RSI, Sims worked as a researcher at the Naval Research Laboratory in Washington, DC. His work focused on the development of efficient system modeling and verification tools.

Sims holds a B.S. in Mathematical Sciences from the University of North Carolina and an M.S. and a Ph.D. in Computer Science from North Carolina State University.

David Hansel

Chief Technology Officer

David Hansel is Chief Technology Officer of Reactive Systems. Hansel has been the lead Reactis developer since he joined Reactive Systems in 2000. He also works closely with customers to help maximize their benefit from Reactis. He holds a B.S. degree in Computer Science from the University of Kaiserslautern and an M.S. degree in Computer Science from the Technical University of Munich.

Michio Morimoto

Director of Asian Operations

Michio Morimoto is Reactive Systems' Director of Asian Operations. Mr. Morimoto directs sales and marketing efforts for all of Asia, except India, and manages post-sales technical support for Japan.

Morimoto previously served as Reactive Systems' Director of Japanese Operations and led the successful 2007 launch of the company's Japan branch office. In that role, Morimoto managed the transition from a distributor to a direct-sales office while growing Japan sales for Reactive Systems' Reactis testing and validation package.

Morimoto is an 20-year veteran of the embedded software industry with a focus on deploying model-based-design solutions in the automotive industry. Prior to moving towards a focus on technical sales and marketing, Morimoto worked as a programmer for three years.

Rance Cleaveland


Rance Cleaveland is Chairman and a co-founder of Reactive Systems, Inc. The Company's technology derives from basic research Dr. Cleaveland performed in the areas of modeling and verification of concurrent systems. He is currently a Professor of Computer Science at the University of Maryland. Dr. Cleaveland previously served as Executive Director of the Fraunhofer Center for Experimental Software Engineering (2005-2014), and was a member of the Computer Science faculty at SUNY at Stony Brook (1998-2005) and North Carolina State University (1989-1998).

Cleaveland holds a B.S. in Mathematics and Computer Science from Duke University, and an M.S. and a Ph.D. in Computer Science from Cornell University. He currently is on the editorial boards of three different research journals and has been a member of the program committees of over 35 different research conferences. He has headed over $6 million of federally-funded research projects over the past 15 years.

Scott Smolka


Scott Smolka is a Director and co-founder of Reactive Systems, Inc. Smolka has been on the faculty at SUNY at Stony Brook since 1982. His work focuses on analysis techniques for reactive systems, and he also has extensive experience in building verification tools, including Winston and the Concurrency Factory.

Smolka holds an A.B. and A.M. in Mathematics from Boston University and a Ph.D. in Computer Science from Brown University. His research has been supported by grants totaling over $7 million from the NSF, the Army, the Air Force, and IBM.