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This is Book 3 of The HPC Tradecraft Master Practitioner series, a capstone demonstrating that pre-1995 bare metal design methods remain directly relevant to modern AI architecture.

In 1986, the author wrote a text adventure game as a bare metal device driver inside the Cray I/O Subsystem. The game, Swiss Adventure, was inspired by Colossal Cave Adventure and written during a Cray Research training class. The source code architecture turns out to be isomorphic to the 2017 \"attention is all you need\" transformer architecture. Similar constraints shape similar solutions.

This book is a work in progress. The current release covers the user experience: what the game does, why it was designed that way, and what the adventurer learns by playing it. The game itself is live and playable at ewbarnard.com with no registration or data collection. The 1986 assembly language source and its PHP port are available on GitHub.

This book is not a normal code walkthrough. This book models the expert thinking common to HPC tradecraft as practiced in the Cray Research era. Typical IT books with sample code work through from one topic to the next. This book builds out a system layer by layer, first designing the user experience, then designing a way to capture and encode the user experience, and then taking advantage of bare metal features and constraints. The companion website allows you to execute the code (by playing the game) while observing the event trace and AI pattern trace moving from request to response.

This book requires a strong working knowledge of Part II of the earlier book Nobody but Us: A History of Cray Research's Software and the Building of the World's Fastest Supercomputer. Part II introduced the necessary concepts for working on bare metal.

The live game: https://ewbarnard.com/
The source code: https://github.com/ewbarnard/SwissAdventure

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Kick off your book project in 3 hours! Live workshop on Zoom. You’ll leave with a real book project, progress on your first chapter, and a clear plan to keep going. Saturday, June 6, 2026. Learn more…

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