The Requirements Operating Model
An operating architecture for regulated engineering in the age of AI. Nine chapters, plus a Prologue and an appendix, released chapter by chapter through the QRA Signal.
About the book
Requirements engineering has matured into a stable framework — EARS, ISO/IEC/IEEE 29148, INCOSE, DO-178C, ISO 26262, and the sector standards alongside them. That framework was built for a world of human writers, human reviewers, and human interpretation of standards. Generative AI has changed the environment in which the framework operates. This book proposes the operating architecture the discipline now requires.
Substrate
A structured and computable representation of engineering knowledge from which requirements, decisions, constraints, and evidence are derived. The foundation of the operating model.
Architecture
Four process layers, a principle governing generation and evaluation, and an organizational function responsible for maintaining the substrate's operating policy.
Path
A maturity model that describes where organizations sit on the way to operating the full system, with a diagnostic for locating your own organization.
The chapters
Chapters release on the QRA Signal cadence. Live chapters are linked below. Upcoming chapters are listed in reading order.
Setting the conditions
What has changed in the engineering environment, and why the discipline now requires an operating architecture.
The Operating Model
Maps the architecture of the model. Introduces the central assertion the rest of the book builds on: a requirement is a governed artifact with computable structure.
The Foundation: The Knowledge Substrate
Develops the model's anchoring layer, including its three defining properties, the Separation Principle that governs it, and the conditions required for it to function in a working engineering environment.
Inputs
How artifacts enter the operating model. Classification by source and risk, and the transformation of arriving artifacts into substrate-legible form.
Transformations
How requirements are authored, refined, and decomposed once inside the substrate. The layer at which generative activity concentrates.
Governance
The layer where the operating model performs its principal architectural work. Deterministic rules, AI-assisted checks, milestone gates, audit records, gap visibility.
Outputs
What the operating model produces. Verified, traceable, verifiable, and defensible artifacts across the admissibility consumers that regulated engineering serves.
Configuration Authority
The function responsible for authoring and maintaining the operational policy that governs the substrate. Organizational patterns for implementing the responsibility.
The Maturity Path
Where organizations sit on the way to operating the full system. The four levels, and the diagnostic by which a reader can locate their organization.
The AI Question
Why AI is a downstream consequence of the substrate rather than a layer of it. The horizontal AI landscape positioned against the operating model.
Integration Across Toolchains
Practical reference for organizations spanning multiple platforms. How the Knowledge Substrate integrates with existing engineering environments.
Companion resources
Working Glossary
Definitions for the terms the book uses across its chapters. Knowledge Substrate, Separation Principle, Configuration Authority, the process layers, the maturity levels, and the standards register the book cites.
Get every chapter as it releases
Chapters release through the QRA Signal, our newsletter for engineering leaders. Subscribe once, receive the whole series.
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