Decwar was among the first multiplayer computer games—eighteen players battling across a shared galaxy on UT Austin's PDP-10 in 1978. We're working to ensure this pioneering software and its cultural context survive.
An organization bringing together faculty, alumni, archivists, and technologists.
DecwarOrg exists to provide a permanent institutional home for the research, preservation, and historical reconstruction of Decwar—a multiplayer space combat game that emerged from the University of Texas Computation Center in 1978.
Written in MACRO-10 assembly and Fortran for the DEC PDP-10, Decwar allowed up to eighteen simultaneous players to engage in tactical starship combat across a shared galactic map. The university distributed the game on magnetic tape for a nominal $50 fee, and it spread to PDP-10 installations worldwide.
More than a technical artifact, Decwar represents an early example of networked social gaming. The terminal rooms where players gathered became proto-online communities, complete with their own social hierarchies, cultural norms, and collective memories.
Restoring the original codebase and stabilizing the build process for historically faithful emulated environments.
Partnership with the Dolph Briscoe Center to acquire and preserve physical artifacts including original magnetic tapes.
Supporting Decwar: A Galaxy in the Machine Room, examining technical architecture and cultural significance.
Documenting how the UT Computation Center functioned as a "proto-online social world" with its own norms and culture.
Recording interviews with original authors, early players, and Computation Center staff before these memories are lost.
Recreating the 1970s machine room experience—the sounds of line printers, tape drives, and heated electronics.
Initiatives spanning technical restoration, academic research, and cultural preservation.
Recovering and stabilizing the original MACRO-10 assembly and Fortran source code. Working toward a reproducible build process targeting period-accurate PDP-10 emulators.
Collaborating with the Dolph Briscoe Center for American History to locate, acquire, and properly house physical materials from the Decwar era.
Development of Decwar: A Galaxy in the Machine Room, examining the game through platform studies, software preservation, and digital culture history.
Recording and preserving firsthand accounts from people who created, maintained, and played Decwar during its active years.
Access preserved source code, documentation, and related materials.
Original MACRO-10 assembly and Fortran source with build instructions for SIMH PDP-10 emulator.
View on GitHubPlayer manuals, technical documentation, and scanned archival materials from the original distribution.
View on GitHubVideos of our projects in action.
View on YouTubeTITLE DECWAR - MULTI-PLAYER STAR TREK GAME
SUBTTL UNIVERSITY OF TEXAS AT AUSTIN - 1978
; Authors: Bob Hysick, Jeff Potter
; Version: 2.3 (November 1981)
SEARCH MONSYM, MACSYM
.REQUIRE SYS:MACREL
MAXPLY==^D18 ; Maximum simultaneous players
GALSIZ==^D64 ; Galaxy size (64x64 sectors)
NUMSTR==^D100 ; Number of stars per galaxy
START: RESET
MOVE P,[IOWD PDLEN,PDL]
MOVEI T1,.FHSLF
RPCAP
MOVEM T2,USRCAP ; Save user capabilities
CALL GLINIT ; Initialize galaxy
CALL PLINIT ; Initialize player structures
JRST MAIN ; Enter main game loopRepresentative excerpt. Full source available in the repositories.
The lineage of Star Trek games at UT Austin, 1971–1982
High school senior Mike Mayfield creates a text-based Star Trek game on an SDS Sigma 7 at UC Irvine—inventing the tactical starship simulation rendered entirely in ASCII.
Mayfield rewrites in HP BASIC. The version spreads widely via David Ahl's 101 BASIC Computer Games, seeding Star Trek variants worldwide.
Grady Hicks and Jim Korp develop a BASIC Star Trek variant for UT Austin's CDC 6600, gaining popularity among Computation Center students.
Dave Matuszek and Paul Reynolds create an expanded Fortran version on the CDC 6600 with significant gameplay depth.
The first multiplayer variant emerges—a two-player Fortran game demonstrating the appeal of human-versus-human starship combat.
Bob Hysick and Jeff Potter release Decwar for the PDP-10. Supporting eighteen simultaneous players, UT Austin distributes copies on tape for $50—spreading globally.
Major update adds new ship classes, expanded combat mechanics, and improved multiplayer synchronization.
The final major release. Decwar runs on dozens of systems globally before fading as institutions migrate to newer architectures.
Recent developments in Decwar preservation and related projects.
Virtual event focused on emerging educational models and opportunities
Discussion of the intense collaboration necessary across 2 classes, the event at large, university resources, etc.
AudioPixel Collider Installation
An interactive installation re-presenting DECWAR as both historical artifact and living system. Rather than treating it as something to be merely preserved, the installation treats it as active material—something to be replayed, reinterpreted, and translated into new media forms, especially sound.
DECWAR was never just a game. It was a social simulation running across terminals, modems, and time zones—players issuing terse text commands into a shared universe that unfolded in real time.
DECWAR as it originally existed: text-only terminal, manual commands. Players construct the galaxy mentally from coordinates and terse system messages.
The same game logic drives live matches while emitting real-time telemetry. Movement, combat, and destruction translate into spatialized audio.
Sonification engines, ambient soundscapes, and visual interpretations created by students treating DECWAR as a generative engine.
"By making the invisible audible, the installation invites visitors to experience computation not as abstraction, but as a living, resonant process."
While DecwarOrg focuses on software preservation, our colleagues at Obsolescence are undertaking a complementary effort: a complete virtual AI Lab - hardware and software - as it stood at MIT in the 1970s, free to play with on your laptop.
Unsurprisingly, this AI Lab of the 1970s has become a mythical place in the world of computer science. A lot of computer jargon and the Hacker Ethic can be traced back to the Lab and its people, as do a lot of now-common software tools.
Read about the ITS reconstructionFurther reading and related preservation efforts.
DecwarOrg is a collaborative, volunteer-driven effort. We welcome contributions from researchers, developers, archivists, and anyone with memories of early multiplayer gaming.
Mk Haley
Faculty
Eric Freeman
Faculty
Noah Smith
Alumni