Eric S. Raymond, American computer programmer and author

Eric Steven Raymond, often referred to as ESR, is an American software developer, open-source software advocate, and author of the 1997 essay and 1999 book The Cathedral and the Bazaar. He wrote a guidebook for the Roguelike game NetHack. In the 1990s, he edited and updated the Jargon File, published as The New Hacker's Dictionary.