Meet John Graham-Cumming

Summary of John Graham-Cumming and jgc.org

jgc.org is the portfolio/homepage of John Graham-Cumming, a programmer, writer, hardware tinkerer, computing-history advocate, and long-running technical blogger. The site is styled like a retro text-mode/terminal interface and acts as a compact index to his work: software, hardware projects, books, publications, blog posts, and public-interest computing/history projects.

John describes himself simply as a “Programmer”. In a 2012 post, Programmer, he wrote about joining Cloudflare and choosing that title because “fundamentally, I make computers do what I want them to do.” His homepage also highlights his Cloudflare career, linking to a Cloudflare article about his path from programmer to CTO and board member.

What he works on

John’s portfolio spans several recurring themes:

• Internet infrastructure and security — especially through his long association with Cloudflare, plus blog posts on privacy, security, iPhone behavior, supply-chain risks, and isolated AI coding environments.
• Open-source and developer tooling — notably the GNU Make Standard Library, a BSD-licensed collection of native GNU Make functions for lists, strings, arithmetic, associative arrays, stacks, memoization, and debugging.
• Machine learning and anti-spam — he created POPFile, an early open-source Bayesian/machine-learning email classifier. On his blog he recounts building it in Perl, restoring its historical website, and how anti-spam work led to connections that later intersected with Cloudflare.
• Hardware hacking and ambient devices — the site lists projects such as bus-time displays, weather devices, aircraft trackers, balloon experiments, and Altoids-tin electronics. One representative post is his ambient bus arrival monitor, built by hacking a Linksys router running OpenWRT and embedding an LED display into a model London bus.
• Computing history — he is closely associated with Plan 28, a project/charity aimed at building Charles Babbage’s Analytical Engine and educating the public about early computing. His blog also covers Alan Turing, Bletchley Park, Babbage, and historical machines.
• Open science and reproducibility — he co-authored The Case for Open Computer Programs, arguing that source code used to generate scientific results should routinely be released.
• Writing and science/technology travel — his homepage points to books including The Geek Atlas and The GNU Make Book. His blog’s “Geek Atlas” posts show a strong interest in places where science, mathematics, technology, and history intersect.
• AI-era information quality — in Low-background Steel: content without AI contamination, he describes creating Low-background Steel as a directory of pre-generative-AI or otherwise uncontaminated online resources.

Blog and style

John Graham-Cumming’s blog has archives going back to 2005 and covers a wide range of technical subjects: hardware, GNU Make, anti-spam, machine learning, security, privacy, mathematics, retro computing, radios, calculators, and public science/history projects. Recent posts include building an isolated Raspberry Pi AI coding server, reflections on AI-assisted software development as “maistro” work, electrical-safety explorations, and teardowns of everyday electronics.

Overall, jgc.org presents John as a hands-on programmer and communicator: someone who builds software and hardware, writes clearly about technical systems, advocates for openness and reproducibility, and has a deep interest in the history and culture of computing.

Social/profile link found on the site: GitHub — jgrahamc.