John Regehr is a Professor of Computer Science at the University of Utah, where he has been on the faculty since 2003. His research focuses on software testing, software verification, and compiler optimization. One of Professor Regehr's current projects is Alive2, a tool for formally verifying (or finding bugs in) optimizations performed by the LLVM compiler. So far, it has resulted in the discovery of more than 50 previously unknown LLVM defects. His previous projects include Csmith, a random program generator that found more than 500 bugs in production-quality C compilers, and C-Reduce, a tool that can greatly reduce the size of a test case that triggers a compiler bug.