Description: Mary Ann's long collaboration with Berni Alder at Lawrence Livermore National Laboratory was instrumental for establishing molecular dynamics as a key tool to study condensed matter systems. In a conversation with Prof. Daan Frenkel (University of Cambridge), she retells her fascinating story and her experiences as a coder over a period of almost thirty years, providing a unique point of view on the scientific and technological development of computer simulation from the early days of molecular dynamics in the late 1950, to the mid 1980s.