David is Principal Engineer for Service Employees International Union. He created the data science training program for Anaconda Inc among other companies. With the advent of deep neural networks he has turned to training our robot overlords as well.

Earlier, David helped build the world's fastest, highly-specialized, supercomputer for performing molecular dynamics. David was a Director of the PSF for six years, chair of its Trademarks Committee for 15 years, and of its Scientific Python Working Group. His columns, Charming Python and XML Matters, written in the 2000s, were the most widely read articles in the Python world.

He has written previous books for Manning, Packt, O'Reilly and Addison-Wesley, and has given keynote addresses at numerous international programming conferences.