David Barkai started his HPC career shortly after receiving a PhD in theoretical physics in the early ‘70s and was active in the field for over 40 years. A central theme of his work was the relationships between applications and architecture, with numerous publications over the years. David’s employment at several HPC companies during their heydays – Control Data, Floating Point Systems, Cray Research, Supercomputing Systems Inc., Intel, and SGI – as well as a stint at NASA, offered him a front-row view of the evolving HPC scene over the last few decades.