· Vice President For Advancement, International Mathematical Olympiad Foundation (Current)2023–
· Professor, Carnegie Mellon University2020–
· Founder, Daily Challenge with Po-Shen Loh2019–
· Associate Professor, Carnegie Mellon University2015–2020
· Founder, Expii, Inc.2014–
· National Coach Of The USA International Mathematical Olympiad Team, Mathematical Association of America2013–2023
· Deputy Team Leader For The United States, 2010-2013 International Mathematical Olympiads2010–2013
· Assistant Professor, Carnegie Mellon University2010–2015
· Research Intern, Microsoft Research Theory Group2009–2009
· Quantitative Analyst Intern, The D. E. Shaw Group2007–2007
· Ph.D., Mathematics, Princeton University2005–2010
· Deputy Team Leader For The United States, 2004 International Mathematical Olympiad2004–2004
· M.S., Mathematics, University of Cambridge2004–2005
· B.S., Mathematics, Caltech2000–2004