Terry A. Davis was an American electrical engineer and programmer who spent more than a decade writing an entire operating system by himself — kernel, compiler, language, editor, file system, games, and documentation — because, he said, God told him to. TempleOS is simultaneously a real engineering achievement, a religious artifact, and one of the most documented cases of severe mental illness lived in public. The record does not ask you to choose between those readings; it asks you to hold all of them.
Identity and formation
Terrence Andrew Davis was born on December 15, 1969, in West Allis, Wisconsin, the seventh of eight children of an industrial engineer. The family moved repeatedly — Washington, Michigan, California, Arizona. He used an Apple II in a gifted elementary program and learned assembly language on a Commodore 64 in the early 1980s, programming through high school. At Arizona State University he earned a bachelor's degree and then, in 1994, a master's in electrical engineering; profiles report a 1440 SAT and a 3.63 GPA, figures sourced to his own telling. From 1990 to 1996 he worked at Ticketmaster in Tempe, programming the company's VAX systems.
Illness and revelation
Davis was a self-described atheist and scientific materialist until March 1996, when recurring manic episodes began — hospitalizations roughly every six months, a flight into the desert, a broken collarbone, a jail stay. He was diagnosed first with bipolar disorder and later with schizophrenia, and came to describe the episode as a revelation from God. Unable to work, he moved into his parents' Las Vegas home on Social Security disability. Between 2003 and 2014 he was not hospitalized again, and his online presence settled into a durable pattern: often incomprehensible or abusive on most topics, and — as observers consistently noted — always lucid about computers.
The work
Around 2003, as 64-bit computing reached desktops, he dusted off code he had written years earlier and began what became a life's work. The system appeared publicly as the J Operating System in 2004, became LoseThos in 2006, SparrowOS in late 2012, and TempleOS in 2013. It is a 64-bit, ring-0-only, single-address-map, non-networked operating system for recreational programming — self-hosting, with its own editor, compiler, 2D/3D graphics library, and the Red Sea file system, all at 640×480 in 16 colors with one-voice PC-speaker sound. He wrote it entirely in HolyC, a just-in-time-compiled language of his own design, "more than C, less than C++." In 2014 VICE measured the system at 121,176 lines of code — comparable to Photoshop 1.0 — every line his.
The software is inseparable from the theology. Davis said he was chosen by God to build the Third Temple prophesied in the Bible, and his site's charter described the OS as "God's official temple." The 640×480, 16-color display was, he insisted, a divine specification — "a covenant like circumcision" — so children could easily draw for God. Its centerpiece, the AfterEgypt oracle, stops a "high-speed stopwatch" on pseudo-random text at a burning bush; he treated the output as God's words, likened it to tongues and Ouija, and used it — plus the NIST randomness beacon — to ask God about war, death, dinosaurs, and favorite bands, publishing the results as "Terry Davis' Rants."
The public life
He posted hundreds of videos — code walk-throughs, demos, hymns, rants — on YouTube channels that were repeatedly terminated for vulgarities, and he was banned or restricted on Something Awful, Reddit, Hacker News, and OSNews. His belief that CIA agents stalked him produced the coinage "glowie," later adopted by far-right forums and documented by The Atlantic. Yet the reception was mostly sympathetic: TechRepublic and OSNews reviewed TempleOS favorably, programming communities made sustained efforts to accommodate him, and an engineer who knew him compared the solo build to one man erecting a skyscraper. In 2017 TempleOS was shown at an outsider-art exhibition in Bourgogne, France; Davis welcomed the attention but said he wished more people used the OS to speak to God. He called himself "the smartest programmer that's ever lived" — a boast the surviving work makes less absurd than it sounds.
Final months and death
In 2018 he stopped taking medication, believing it limited his creativity, and left his sister's home in Arizona for California and then Oregon. Homeless in The Dalles, he accepted fans' care packages but refused housing. On August 11, hours after uploading a final video — "Terry Davis: Rises to Throne," recorded on a bench at the Wasco County library, explaining he had deleted most of his videos so as not to "litter" the Internet — he was struck by a Union Pacific train while walking the tracks. He was 48. The engineer considered it suicide; investigators could not determine whether it was suicide or accident. The Dalles Chronicle confirmed his identity after fans worldwide called the paper about an unnamed homeless man. His family asked supporters to donate to mental-health organizations. The community archive — a terabyte of videos, site captures, and ISOs on the Internet Archive, plus the memorial mirror at templeos.org — is kept under his own public-domain dedication.
What the record does not settle
The soft spots are real: the line counts vary by source and date; the manner of death was never resolved; his post-1996 employment history is self-reported; and the true start of the codebase — circa 1993 by Wikipedia's account, or post-2003 per the VICE profile — is fuzzy. More fundamentally, sources disagree on what TempleOS is: religious vision, engineering feat, or symptom of schizophrenia. The index preserves all three readings rather than smoothing them over.
This index was compiled from public sources and does not imply the subject's endorsement. Citations live in the packet's source catalog.