NetHack has been in development for almost forty years, and it has always been free. Mike Stephenson posted it to Usenet in July 1987 as sixteen messages of C source code, and anyone who wanted to play had to compile it first. What they got was a descendant of Rogue: a dungeon drawn in letters and punctuation, a new layout every game, and a character lost for good at death. What made it different was how much it knew. Martin Hollis, who led the team behind GoldenEye 007, picked it as one of his desert-island games in 2008: “It’s about learning the rules of this dungeon — the magic and the mythological creatures that reside in it. It’s a game for scientists and designers. The interactivity between the objects — everything works with something else you don’t know about. And when you die, you forget and you have to discover again. You really die!”
Fast facts
- First posted: 28 July 1987, to the Usenet newsgroup comp.sources.games, by Mike Stephenson.
- Ancestors: Hack, begun by Jay Fenlason, rebuilt by Andries Brouwer and ported to the PC by Don Kneller.
- Developers: the NetHack DevTeam, a group of volunteers, since version 3.0.
- Key versions: 1.4 (1987); 3.0.10, current in early 1992; 3.1.0, on Amiga public-domain disks by July 1993; 3.3.0 (December 1999); 3.4.3 (December 2003); 3.6.0 (December 2015); 5.0.0 (2 May 2026).
- Licence: the NetHack General Public License (1989); the source has always been public.
- Goal: retrieve the Amulet of Yendor.
From Hack to NetHack
NetHack is a game several people deep. According to Andries Brouwer, Hack “was originally written by Jay Fenlason (at lincolnsudbury: 29 East St., Sudbury Mass.)”, Lincoln-Sudbury Regional High School, “with help from Kenny Woodland, Mike Thome and Jon Payne”. Fenlason’s copyright line is dated 1982. “Basically it was an implementation of Rogue,” Brouwer wrote, “however, with 52+ instead of 26 monster types.”
Brouwer, working at the Stichting Mathematisch Centrum in Amsterdam, rewrote it. He posted Hack 1.0 to the newsgroup net.sources on 17 December 1984, in fifteen parts. It was so popular that Gene Spafford created a newsgroup, net.games.hack, to move the discussion out of net.games: “There has been an incredible amount of traffic generated by users (and abusers) of the ‘hack’ game recently posted to the net.” The last version, 1.0.3, went out on 23 July 1985. By then, Brouwer wrote, it was “more than three times as large, with important additions like the dog, the shops, long worms, the endgame, and contains very little if anything from the original sources.”
Others carried Hack further. Don G. Kneller ported it to MS-DOS as PC HACK, and R. Black took that to the Atari ST. The versions drifted apart until Mike Stephenson merged them. His posting to comp.sources.games on 28 July 1987 came with a note from the moderator: “OK hack fans, here it is. This posting and the following 15 compose the latest version of hack, known as nethack.” Stephenson’s own note asked players to send him fixes, because he had not got it running under Xenix or DOS. The DevTeam’s history file dates his merged NetHack 1.4 to 1987 too; versions 2.2 and 2.3 followed, all released by posting the source to Usenet.
On every computer
Home computer owners met NetHack on public-domain disks. Fred Fish’s Amiga collection carried NetHack 2.3, ported by Olaf Seibert, across two disks, Amazing Computing noting in May 1989 that it “was too large to fit on a single disk, even when zoo’d”. That month Commodore Magazine’s Amiga public-domain column told readers, “If you liked Hack, you’ll love NetHack.” It listed the new character classes: Valkyries, “tough female warriors that can withstand severe punishment”; Healers, who can “detect the medical state of any creature at any time”; Samurai; Ninjas “with plenty of throwing stars”; and Priests. Anyone could now learn spells from a spellbook, but “nothing is easy in NetHack”: the books “are only useful for a limited time, as the magical runes fade with each reading.” The reviewer’s one complaint was the look. Almost everything was “just the standard ASCII symbols”.
A larger team took over for version 3.0, and from it grew the NetHack Development Team, usually called the DevTeam. In March 1992 Computer Gaming World surveyed public-domain role-playing games and named NetHack, Moria and Ultra-Larn as the most popular. Gerald Graef wrote that NetHack “can now be found on virtually any computer, usually with only minor cosmetic differences”. The goal, as in Rogue, was “to wrest the Amulet of Yendor from the Wizard of Yendor”. Along the way were special levels (“the Tower of Vlad the Impaler, the Castle buried deep in the Earth and a special endgame level”), shops and beehives, and artefacts with borrowed names: the warhammer Mjollnir, “with apologies to Thor”, and the broadsword Stormbringer, “with apologies to Elric”. “NetHack is not a completely serious game,” Graef added, “as is clearly seen when playing a tourist.” The current version was 3.0.10, with 3.1 in the works, and anyone with Usenet access could get “both the games and their source code”.
Version 3.1 was a rewrite, and it reached the Amiga on Fred Fish disk 822, with its C source on two more. The Australian Commodore and Amiga Review’s public-domain column greeted it in July 1993 with the genre’s usual boast: these games have “no sound, crummy graphics and amazingly addictive gameplay”, and “you can be really, truly and genuinely addicted to them for six months and still be learning stuff.” It warned that 3.1.0 needed 2MB of memory and two floppy drives. According to the DevTeam’s history file, the new version added “multiple dungeons, a new display, special individual character quests, a new endgame and many other new features”. Warwick Allison drew a set of graphical tiles for the Atari version, and the DevTeam then added tile support for other machines, so players could choose pictures over letters. Version 3.3, in December 1999, separated a character’s race from its role, added Monks and Rangers to the Archeologists, Barbarians, Cavemen, Healers, Knights, Priests, Rogues, Samurai, Tourists, Valkyries and Wizards, and let the player ride a steed.
The long wait
NetHack 3.4.3 came out in December 2003, and for more than a decade it was the latest version. In the history file’s words, it “proved to be a remarkably stable version that provided continued enjoyment by the community for more than a decade”, while the DevTeam “slowly and quietly continued to work on the game behind the scenes.” Players filled the gap with variants of their own, among them SporkHack, UnNetHack and NitroHack. In September 2014 someone else leaked a snapshot of the DevTeam’s unfinished code. The team retired its version numbers and announced that there would never be an official 3.4.4 or 3.5.
NetHack 3.6.0 appeared in December 2015. It merged the team’s work since 2003 with some of the players’ favourite patches, and it paid tribute to Terry Pratchett, who had died during its development and whom the DevTeam counted among “the significant inspirations for many of the humorous and fun features found in the game.” Bug-fix releases continued up to 3.6.7 in February 2023.
This time the next version was developed in public, on GitHub and SourceForge, under the label NetHack 3.7. In early 2026, with the code nearly ready, the DevTeam decided it had changed enough to deserve a new major number, but not 4.0, which might have been confused “with existing variants”. NetHack 5.0.0 was released on 2 May 2026 with more than 3,100 fixes and changes. Its source code follows the C99 standard, it replaces the old level and dungeon compilers with Lua scripts that the game loads as it runs, and it cannot read saved games from earlier versions.
Influence
In the 1990s NetHack was a name that game designers used as shorthand. Blizzard’s Bill Roper told PC Zone in 1999 that when the team behind Diablo pitched the game, they said: “Imagine Rogue and Nethack and Moria in a gothic fantasy setting, but with 90s graphics.” (The magazine printed “Moyra”.) Diablo started out turn-based, and its designer Erich Schaefer told Edge in 2010 that this “was based on the Nethack or Rogue-style of game that [David] Brevik liked a lot.”
Demis Hassabis, then running Elixir Studios, used NetHack in Edge in 1999 to make the opposite case. One of his team described playing it “in its original ASCII form as the pinnacle of gaming”, but “he’s in a minority”. Diablo was a blockbuster, while NetHack “will never have anything more than a small but dedicated following of the hardest core gamers.”
The source code and the licence
NetHack has been released as source code from the start: first on Usenet, where the postings “remained available in various archives accessible via ftp and uucp after expiring from the newsgroup”, and now on GitHub, where the DevTeam publishes its releases and work in progress.
The terms are Stephenson’s NetHack General Public License of 1989, “based on the BISON general public license, copyright 1988 Richard M. Stallman”. Anyone may copy the game, change it and pass it on, so long as the recipients receive the same rights and the source code. Any work built from it must be licensed “at no charge to all third parties on terms identical to those contained in this License Agreement”; a distributor may charge only “for the physical act of transferring a copy”. That is why the variants exist, and why each of them is free as well. The game’s copyright notice names the Stichting Mathematisch Centrum, where Brouwer worked, and M. Stephenson. Brouwer’s original Hack has since been freed separately: after the Centrum (now CWI) allowed free redistribution, he reconstructed the 1985 sources and put them under a BSD-type licence, with Fenlason’s permission for the code he had written.
Sources
- comp.sources.games volume 2 issues 1–16, “nethack - display oriented dungeons & dragons”, posted 28 July 1987 by the moderator for Mike Stephenson (web, Usenet archive): the first posting of NetHack; the moderator’s and author’s notes. https://ftp.acc.umu.se/mirror/archive/ftp.sunet.se/pub/usenet/ftp.uu.net/comp.sources.games/volume2/nethack/
- NetHack DevTeam, “history”, in the NetHack 3.6 and 5.0.0 source distributions (web): Fenlason and his helpers; Brouwer at the Stichting Mathematisch Centrum; Kneller and Black; Stephenson, NetHack 1.4 in 1987 and Usenet distribution; the teams behind 3.0 and 3.1 and what 3.1 added; Seibert’s Amiga port; Allison’s tiles; 3.3’s races, roles and riding; 3.4.3 and the variants; the 2014 leak; 3.6.0 and Terry Pratchett; 3.6.7; the 3.7 work in progress and the choice of 5.0. https://github.com/NetHack/NetHack/blob/master/dat/history and https://github.com/NetHack/NetHack/blob/NetHack-3.6/dat/history
- Andries Brouwer, “Hack” (web page, CWI Amsterdam): Fenlason at Lincoln-Sudbury and the 1982 copyright; “an implementation of Rogue”; Hack 1.0 on 17 December 1984; net.games.hack; 1.0.3 on 23 July 1985 and what it added; the BSD-type licence. https://homepages.cwi.nl/~aeb/games/hack/hack.html
- Fred Fish disks 189 and 190, Amazing Computing vol. 4 no. 5, May 1989: NetHack 2.3 for the Amiga, with source, by Olaf Seibert.
- Graham Kinsey, “Amiga Public Domain”, Commodore Magazine vol. 10 no. 5, May 1989, pp. 74–75: NetHack by Olaf Seibert; classes, spellbooks, fountains and graphics.
- “Hot PD” column, The Australian Commodore and Amiga Review vol. 10 no. 7, July 1993: NetHack 3.1.0 on Fish disks 822–824; its appeal and its memory needs.
- Gerald Graef, “Public Domain Computer Role-Playing Games”, Computer Gaming World issue 92, March 1992, p. 64: NetHack 3.0.10.
- “The World According to… Blizzard’s Bill Roper”, PC Zone issue 80, September 1999, pp. 134–137: the Diablo pitch.
- Demis Hassabis, column, Edge issue 77, autumn 1999: NetHack and its following.
- Paul Drury, “Desert Island Disks: Martin Hollis”, Retro Gamer issue 46, 2008, p. 83.
- The making of Diablo, Edge issue 210, January 2010: the turn-based first version.
- NetHack DevTeam, “NetHack 5.0.0: Release Notes”, 2 May 2026 (web). https://www.nethack.org/v500/release.html
- NetHack DevTeam, “NetHack General Public License” and site copyright notice (web). https://www.nethack.org/common/license.html