Microsoft's Open Source Programs Office (OSPO), Team Xbox, and Activision have collaborated to open source the classic text adventure games *Zork I*, *Zork II*, and *Zork III*. The move, announced November 20, 2025, aims to preserve the historically significant code and make it available for educational and exploratory purposes under the permissive MIT License. A Game That Changed How We Think About Play *Zork* pioneered interactive storytelling by relying solely on text, sparking players' imaginations with its detailed descriptions and challenging puzzles. The games ran on the Z-Machine, a virtual machine that allowed for cross-platform compatibility. Preserving a Piece of History The source code release contributes directly to existing historical repositories on GitHub. The repositories now include:

Source code for *Zork I*, *Zork II*, and *Zork III*.
Accompanying documentation.
Clear licensing and attribution under the MIT License.

This release focuses specifically on the code, excluding commercial packaging and marketing materials. Trademark and brand rights remain with their respective owners. Running Zork I-III Today While *Zork* remains commercially available via *The Zork Anthology*, open-source enthusiasts can compile and run the games locally using tools like ZILF, a modern Z-Machine interpreter. The article also provides detailed steps on compiling and playing the game via ZILF. Additionally, users can use CLI implementations in Python with a CRT filter for a retro look. Continuing the Journey Contributions to the source code are welcome, with the goal of preservation and education rather than modernization. Microsoft encourages developers to explore, study, and learn from this foundational piece of gaming history.