Interactive software exhibit that lets you play Zork 1 while browsing its ZIL source code side by side in real time.
Key Takeaways
The exhibit exposes Zork’s ZIL (Zork Implementation Language) source, including the shared VERBS file for the trilogy, dated 7/25/83 by contributor SEM.
Visible routines include V-SAVE, V-RESTORE, V-QUIT, V-INVENTORY, and V-VERIFY – the full command dispatch layer of the Z-machine.
Spell mechanics in Zork II (FEEBLE, FUMBLE, FREEZE, FLOAT, FRY, FILCH) are implemented as named word constants matched against a wand state machine, not a table.
The source contains a Tandy Corporation licensing branch inside V-VERSION, a concrete artifact of Infocom’s distribution deals.
The codebase became explorable after Microsoft open-sourced the Zork code in late 2025.
Hacker News Comment Review
Commenters frame this primarily as a Z-machine transparency tool: seeing verb dispatch, spell logic, and room transitions live removes the need to attach a debugger to an interpreter.
A navigation inconsistency was flagged: going west then east can land in a different room, suggesting the exhibit’s state synchronization with Z-machine room logic has edge cases.
The open-sourcing of Zork prompted broader questions about what modern tooling for Infocom-style games looks like, with Inform 6 mentioned as an open question for new interactive fiction development.
Notable Comments
@Joe_Cool: “Z-machine internals without needing to run a debugger” – clearest one-line summary of the exhibit’s value.
@bzzzt: Points to Wilderland as a prior art parallel for another text adventure engine.
