John Carmack
Abstract
John Carmack wrote the rendering engines that created the first-person shooter: Wolfenstein 3D (1992), Doom (1993), and Quake (1996). Then he kept doing improbable things. He released his engines as open source and watched a generation learn 3D programming from them, spent a decade building rockets that won two NASA-backed landing prizes, became CTO of Oculus and shipped consumer virtual reality, and in 2022 left Meta to chase artificial general intelligence with a deliberately tiny startup. Few programmers have had one career this consequential. Carmack has had four.
Kansas
John Carmack was born on August 21, 1970, in Shawnee Mission, Kansas. The childhood was not idyllic. At 14 he and other boys broke into a school to steal Apple II computers, using a thermite mixture to melt through a window; a psychiatric evaluation described him as “a brain on legs”, and he spent a year in a juvenile home. He lasted two semesters at the University of Missouri-Kansas City before dropping out to program for money.
The job that mattered was at Softdisk in Shreveport, Louisiana, where he met John Romero and Tom Hall. In September 1990 Carmack worked out adaptive tile refresh, a trick that gave a cheap EGA PC the smooth side-scrolling that only consoles could do. The team cloned the first level of Super Mario Bros. 3 over a weekend as a demo and mailed it to Nintendo, which politely declined to put Mario on the PC. So they built their own character instead: Commander Keen, published as shareware through Apogee in December 1990. On February 1, 1991, the group quit and founded id Software.
The Engines
What followed is told in detail in The PC Gaming Revolution and Game Engines: Wolfenstein 3D (May 1992) built the first-person shooter genre on raycasting, Doom (December 10, 1993) added variable geometry, lighting, and networked deathmatch, and Quake (June 22, 1996) delivered true 3D and internet play. Carmack’s contribution was consistent across all three: rendering code that did things the hardware was not supposed to be able to do, rewritten from scratch for each generation. GLQuake (1997) then gave the new 3D accelerator cards their killer app and helped push OpenGL into gaming.
Carmack worked in public in a way that was unusual for the 1990s. He published his day-to-day engineering notes as .plan files readable by anyone with the finger command, gave marathon technical keynotes at QuakeCon, and once told a lawyer that programmers made poor witnesses because they are compulsively precise. He also gave away his Ferrari 328 as the prize of the 1997 Red Annihilation Quake tournament (see The First Esports Champion Won John Carmack’s Ferrari).
Giving the Code Away
Carmack persuaded id to release its engine source code once the commercial value had been extracted: Wolfenstein 3D in 1995, Doom in 1997 (relicensed under the GPL in 1999), Quake in 1999, Quake II in 2001, Quake III Arena in 2005, Doom 3 in 2011. The consequences are still running. Source ports keep Doom alive on every processor that can address a framebuffer, which is the substrate of the “can it run Doom?” folk genre, and the released engines became free textbooks: a generation of graphics programmers learned by reading Carmack’s code. He argued the position plainly, stating in his 2009 GPL release note for Wolfenstein 3D’s iPhone port that programmers stand on each other’s work and pretending otherwise is theft of a different kind. He has also been a vocal opponent of software patents, which he described as “mugging” the field.
Rockets
In 2000 Carmack started Armadillo Aerospace, a self-funded vertical-takeoff rocketry company staffed largely by volunteers in a Dallas warehouse. It was a serious operation with a hobbyist’s budget: Carmack put in millions of his own money and spent weekends welding. Armadillo won Level 1 of the NASA-funded Northrop Grumman Lunar Lander Challenge in October 2008 ($350,000) and Level 2 in September 2009 ($500,000), flying rocket-powered landers that took off, hovered, translated, and landed under computer control.
Dead end: Armadillo Aerospace
Armadillo never found a business. Suborbital tourism went to funded competitors, and the company’s low-cost incremental approach could not keep pace once SpaceX and Blue Origin showed what billions of dollars buy. After a failed rocket flight in January 2013 and no new funding, Carmack put the company into “hibernation mode” that year. He called it a hobby that had been run like a business, and went back to day jobs that pay for themselves.
Virtual Reality
At E3 2012 Carmack demonstrated a duct-taped head-mounted display built by a 19-year-old named Palmer Luckey, running Doom 3. The demo made the Oculus Rift famous. On August 7, 2013, Carmack became CTO of Oculus VR, resigning from id Software that November; Facebook bought Oculus for about $2 billion in 2014 (the wider story is in The History of Virtual Reality). His technical fingerprints are on the details that make VR tolerable, latency reduction above all, and on the mobile side: Gear VR and the standalone Quest line followed his insistence that VR had to work without a gaming PC.
The move came with a lawsuit. ZeniMax, id’s parent company, sued Oculus over trade secrets; in February 2017 a jury awarded ZeniMax $500 million from Oculus and its executives for NDA breach and copyright claims, while clearing Carmack of misappropriating trade secrets for himself. Carmack, offended by expert testimony that his code was “non-literally copied”, countersued ZeniMax for $22.5 million in unpaid acquisition money; the parties settled in 2018.
He stepped back to “Consulting CTO” in November 2019 and left Meta on December 16, 2022, with an internal memo that promptly leaked: the company, he wrote, ran at half the effectiveness that would make him happy, and “we are constantly self-sabotaging and squandering effort.” It was a rare public verdict on Big Tech engineering culture from someone who had spent a decade inside.
Keen Technologies
In 2022 Carmack founded Keen Technologies to work on artificial general intelligence, raising $20 million and keeping the team deliberately small, on the theory that the code for AGI will be simple enough that a few people can find it, “tens of thousands of lines of code” by his estimate. It is a contrarian bet against the scaling-first consensus of the LLM era. He received the BAFTA Fellowship in 2016, the first engineer honored primarily for game technology.