Restoring Jay Fenlason's original 1981–1982 Hack to run on modern Linux.
protoHack applies the same preservation-first philosophy as restoHack, but to an earlier, pre-distribution working tree. This source predates every currently known distributed Hack variant. While restoHack restored the 1985 release, protoHack reaches further back to the original 1981-82 codebase.
This source was widely considered lost for over 40 years. Jay Fenlason put Hack on the USENIX 82-1 distribution tape and, by his own account, "forgot about it." By the time he spoke to Julie Bresnick in 2000, he had long since moved on; he still played his original version at home, but had "voluntarily avoided participation pretty much since spawning the original Hack almost 20 years ago." Andries Brouwer's near-total rewrite as Hack 1.0 (1984) became the version the world knew, and Fenlason's original source largely dropped out of the historical record.
It resurfaced in 2025 when Brian Harvey, who had been Computer Director at Lincoln-Sudbury Regional High School during Hack's development, provided his preserved copy of the school's PDP-11 backups to Dan Stormont for the Snap!Hack educational project. Dan published the complete original working tree at Sustainable-Games/fenlason-hack.
Chain of custody:
- Jay Fenlason — original author, 1981-82 (with Kenny Woodland, Mike Thome, and Jon Payne)
- Brian Harvey — preserved from LSRHS PDP-11 backups, 1982-2024
- Dan Stormont — Snap!Hack project, 2024-present
This is Hack before it became Hack. Before Andries Brouwer rewrote it as Hack 1.0 at CWI Amsterdam, before Huisjes and de Wilde expanded it at VU Amsterdam, before NetHack; this is Jay Fenlason's high school original from Lincoln-Sudbury Regional High School:
- Amulet of Frobozz — not yet renamed to "Amulet of Yendor"
- No shops — shopkeepers were added later by the Dutch developers
- No starting pet — you're on your own down there
- Displacer beast — appears to be the only known Hack variant to include one (the 'd' slot was later reassigned to "dog" when pets were added)
- 56 monsters across 8 depth levels — including unique creatures like "ugod", "xerp", and "zelomp" that appear nowhere else
- Authentic misspellings — "homonculous", "gelatenous cube" (preserved, not fixed)
- 8 source files — the entire game, written on a PDP-11/70 running V7 Unix (2.8BSD alpha test site)
- Preserve original behavior and structure
- Make the code buildable on modern POSIX systems
- Avoid gameplay or design changes beyond what is required for portability
- Document provenance and historical context
- Not a fork of NetHack
- Not a gameplay modernization
- Not a rewrite or reimagining
Requires: ncurses, crypt (libxcrypt on modern distros)
Produces: hack and mklev in the build directory, plus a
hackdir/ with runtime data files.
cmake -B build -DCMAKE_BUILD_TYPE=Debug
cmake --build build
cd build
./hackVerified builds: Arch Linux, Alpine Linux, macOS (thanks @karianna).
Static Binary (Release Archive)
Some releases include a prebuilt static Linux binary. To run it:
mkdir -p ~/Games/restohack
cd ~/Games/restohack
tar -xzf protoHack-*-linux-x86_64-static.tar.gz
./run-hack.shArchive contents:
hack— the game binarymklev— level generator (invoked by hack)hackdir/— runtime data (news, moves, record, perm, save/)run-hack.sh— launcher
If you see permission errors, make sure hackdir/ and hackdir/save/ are writable.
- Terminal too small: the game requires at least 80x24.
- Permission errors: ensure
hackdir/andhackdir/save/are writable. - Save/restore issues: verify
hackdir/save/exists and has group-writable perms (mode 2775 in packaged builds).
- Occasionally the input buffer may get wedged. If that happens, close the window and remove
hackdir/game.lock, then restart the game. This typically only happens in MAGIC mode; I’m working on it.
The restoration converts K&R C (1978-era function definitions, implicit types, V7 Unix system calls) to ANSI C with POSIX equivalents. All original logic, bugs, and behavior are preserved as faithfully as possible.
The src/root/ tree corresponds to the original USENIX 82-1 submission and is fully playable after restoration. This is the historically significant version distributed on the tape.
The src/exp1/ tree represents a later, experimental refactor by Fenlason and has not yet been converted; it is included for completeness and future work.
| File | Status | Notes |
|---|---|---|
| hack.c | Done | 32 functions, termios rewrite for terminal I/O |
| hack.main.c | Done | 11 functions, V7 signal handler cleanup |
| mklev.c | Done | 19 functions, qsort/stdarg/signal fixes |
| rnd.c | Done | 4 functions |
| hack.h | Done | Modern prototypes |
| hack.pri.c | Done | Display/rendering, termcap calls |
| hack.do.c | Done | Player commands, pointer arithmetic issues |
| hack.do1.c | Done | More player commands |
| hack.mon.c | Done | Monster behavior |
| hack.lev.c | Done | Level file I/O, exec's mklev |
Not started. Will be ported after root is complete. This is a post-release refactoring that split the code into 12 files with shared headers. Root is the version that was submitted for the USENIX 82-1 distribution tape — it has the README with install steps, matching file counts, and packaging documentation. exp1 is an ongoing development branch that was never formally packaged or distributed.
This is a two-binary game, a consequence of PDP-11 memory constraints.
hack is the main game. When it needs a new dungeon level, it execs
mklev as a separate process to generate the level file, then reads the
result back. This architecture is preserved; the binaries are not merged.
A compat.h shim handles the BSD-to-POSIX translation: index becomes
strchr, gtty/stty become tcgetattr/tcsetattr, V7 variadic
conventions become <stdarg.h>, and hardcoded paths become a CMake-defined
HACKDIR.
Rogue (1980, Toy/Wichman/Arnold, UC Santa Cruz)
|
v
Fenlason Hack (1981-82, Lincoln-Sudbury) <-- you are here
|
+---> PDP-11 Hack (~1983/84, Huisjes & de Wilde, VU Amsterdam)
| |
| +---> PC/IX Hack (1985, IBM PC UNIX port)
|
+---> Hack 1.0 (Dec 1984, Brouwer, CWI Amsterdam)
| |
| +---> Hack 1.0.1 (Jan 1985)
| +---> Hack 1.0.2 (Apr 1985)
| +---> Hack 1.0.3 (Jul 1985) <-- restoHack restores this one
| |
| +---> NetHack 1.3d (Jul 1987)
| |
| +---> ... all NetHack versions
github.com/Sustainable-Games (Dan Stormont):
- fenlason-hack — The unmodified original 1982 working tree as preserved by Brian Harvey
- Snap!Hack — Educational reimplementation in Snap!; the project that prompted Brian Harvey to share the preserved source in the first place
- restoHack — The sequel that came first: restoration of Hack v1.0.3 for modern systems
- hack-1.0 — Andries Brouwer's Hack 1.0 (CWI Amsterdam, Dec 1984)
- hack-pdp11 — PDP-11/PC/IX Hack by Huisjes & de Wilde (VU Amsterdam)
See docs/research/ for historical analysis:
- TIMELINE.md — Corrected chronology with primary sources
- COMPARISON.md — Detailed monster table and feature comparison across all known early Hack variants
- login_june-1982.pdf — The ;login: issue announcing the USENIX tape
- Jay Fenlason
- Mike Thome
- Jonathan Payne
- Kenny Woodland
- Brian Harvey
- Dan Stornmont
This source code was created primarily by Jay Fenlason, with additional contributions from Kenny Woodland, Mike Thome, and Jon Payne.
It is shared under the Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License (CC-BY-NC-SA 4.0), as specified by Jay Fenlason when the source was archived by the Snap!Hack project. A copy of the license is available at: https://creativecommons.org/licenses/by-nc-sa/4.0/
This license choice reflects the terms under which the source was archived and is not a new restriction introduced by this project.
This repository preserves historical source code. Certain identifiers may reference third-party intellectual property and are retained solely for archival accuracy. No affiliation or endorsement is implied.