John Graham-Cumming John Graham-Cumming is the CTO of Cloudflare. He studied mathematics and computation at Oxford University and stayed for a doctorate in computer security. As a programmer he has worked in Silicon Valley and New York, the UK, Germany and France. His open source POPFile program won a Jolt Productivity Award in 2004. He is the author of a travel book for scientists published in 2009 called The Geek Atlas and has written articles for The Times, The Guardian, The Sunday Times, The San Francisco Chronicle, New Scientist and other publications. @jgrahamc