John Walker didn’t find his success overnight: the son of a doctor and a nurse, he studied astronomy before switching to electrical engineering; founded the hardware company Marinchip Systems in 1976; and then co-founded Autodesk in 1982. The company’s first product was an eponymous office automation program.

It was AutoCAD that finally gave Autodesk and Walker their fame. Walker didn’t invent computer-assisted design — the term “CAD” was coined in 1959 — but previous CAD software had largely been limited to more powerful mainframe computers; AutoCAD was one of the first implementations to be available to the masses.

Originally developed as Interact CAD, AutoCAD was demoed for CP/M computers at the 1982 Comdex industry trade show, where it was met with wild acclaim. It ushered in a design revolution in architecture, engineering, interior design, manufacturing, and more. AutoCAD is still used and supported today, with the latest version having been released for Windows and macOS in May 2024.

Walker himself was a talented software developer and author who enjoyed writing more than he did managing: shortly after Autodesk went public in 1985, he stepped down as CEO. He moved to Switzerland in 1991 and retired in 1994 at the age of 45.

In retirement, Walker wrote many books, including The Hacker’s Diet: How to Lose Weight and Hair Through Stress and Poor Nutrition (which, “notwithstanding its silly subtitle, is a serious book about how to lose weight,” wrote Walker); and The Autodesk File: Bits of History, Words of Experience, an 889-page PDF that saw its fifth and final revision in 2017.

Walker was 74 when he died from head injuries sustained from a fall at home.