Microsoft makes Zork open-source

Original Article ↗ Hacker News Discussion ↗

Ownership and Corporate History

  • Many comments retrace how Microsoft came to own Zork: Infocom was bought by Activision in the 1980s, Activision Blizzard was acquired by Microsoft in 2023.
  • People are surprised at the breadth of Microsoft’s game IP (Infocom, Sierra, Blizzard, id via Zenimax, etc.), and how easy it is to forget who owns which classic brands.

What’s Actually New

  • Several note that Zork source has been “around forever” (e.g., MIT’s original MDL “Dungeon” version and leaked Infocom sources).
  • The key change: Zork I–III in the historicalsource GitHub org now have an explicit MIT license via a Microsoft-approved PR.
  • Other Infocom repositories remain “source available” for study/archival only, with explicit notes that they are not open source.

Tech Stack: MDL, ZIL, Compilers

  • Discussion clarifies lineage: original mainframe Zork in MDL, commercial Zorks in ZIL (a MDL-derived Lisp dialect) targeting the Z-machine VM.
  • Commenters debate MDL’s status: “obscure” vs. an important MIT PDP‑10 language with advanced types and data structures.
  • Original Infocom toolchains (ZILCH, mainframe environment) are effectively lost; modern ZILF is the practical compiler and is explicitly recommended.
  • Various ports (Fortran, f77, C) and interpreter implementations (e.g., Frotz, Apple II interpreters) are cataloged; some interpreter sources exist in a legal gray area and people hope Microsoft will officially license them too.

Licensing and Copyright Details

  • Questions arise about the 2025 copyright date on the MIT license; responses note it likely reflects this publication/version, not original creation.
  • There’s back-and-forth on whether narrative text is covered by the code license; one view is that Microsoft is mainly concerned with trademarks/branding, but this is flagged as a legal gray area.

Reactions: Nostalgia vs. Skepticism

  • Many express deep nostalgia, personal stories of playing or trying to write adventure games, and appreciation for historical preservation.
  • Others see this as low-risk PR around “old, crusty, obsolete” code that has no commercial value.
  • Some criticize the blog post’s tone as “LLM-ish,” while others defend it as just a particular writing style.

Future Uses and Derivatives

  • People are excited about derivative works: ports to Inform 6, translations, educational study, packaging in Linux distros, Docker images, and even AI-assisted visualization or play.
  • There’s strong desire for Microsoft to similarly open source more Infocom titles and other classic engines (Sierra, AoE, id Tech), though legal entanglements (e.g., Hitchhiker’s rights, BBC/estates) are acknowledged.