He completed his Ph.D. in the Computer Science Department at the University of California, Santa Cruz in 2006. He was a postdoctoral associate at Massachusetts Institute of Technology and a member of the Program Analysis Group. He was a Chief Technical Officer (CTO), and led a 25-person team at the Nara Vision Co. Ltd, a leading Internet software company in Korea for six years.His core research area is Software Engineering, focusing on software evolution, program analysis and empirical studies using machine learning technologies. He publishes his work on top venues such as TSE, ICSE, FSE, AAAI, SOSP and ISSTA. He is a four-time winner of the ACM SIGSOFT Distinguished Paper Award (ICSE 2007, ASE 2012, ICSE 2013 and ISSTA 2014). Besides, he received various awards including 2010 and 2011 Microsoft Software Innovation Awards and 2011 Google Faculty Research Award. Connect