In 2011 IBM will install the Blue Waters computing system with over 300,000 cores and 10 petaflops peak performance in Urbana, Illinois. One of the first programs to run on the machine will be the molecular dynamics code NAMD, which was specified as a target petascale application by the NSF due to its dual status as both a highly scalable parallel code and a practical NIH-funded scientific tool with thousands of users.

NAMD is based on the prioritized message-driven execution capabilities of the Charm++ parallel runtime system. NAMD and Charm++ have evolved through a close collaboration between computer science researchers working to make parallel programming easier and computational scientists seeking flexible, reliable, and high-performance biomolecular simulation tools. In this lecture I will relate lessons learned from my career at the nexus of this unique and highly successful collaboration.