First with 4 years as assistant Prof. From the CV:

Harvard University School of Engineering and Applied Sciences

Gordon McKay Professor of Computer Science

July 1, 2010 ­ July 1, 2011

Harvard University School of Engineering and Applied Sciences

Thomas D. Cabot Associate Professor of Computer Science

July 1, 2007 ­ June 30, 2010

Harvard University School of Engineering and Applied Sciences

Assistant Professor of Computer Science

July 1, 2003 ­ June 30, 2007

Intel Research, Berkeley

Senior Researcher

August 2002 ­ July 2003