Hal is a program manager for computer-science research in the US Department of Energy Office of Science’s Advanced Scientific Computing Research (ASCR) program. Prior to joining ASCR, Hal was the Lead for Compiler Technology and Programming Languages at Argonne National Laboratory’s Leadership Computing Facility. As part of DOE’s Exascale Computing Project (ECP), Hal had a leadership role in several multi-institution activities, including several focused on the LLVM Compiler Infrastructure project and a project focused on the Kokkos and RAJA C++ libraries. Hal has been involved with ISO C++ standardization for nearly a decade, and he currently serves as vice chair of the US C++ standards committee. He graduated from Yale University in 2011 with a Ph.D. in theoretical physics focusing on numerical simulation of early-universe cosmology.