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Architecture decision (ADR)

A design choice recorded with its rationale, not stated as a requirement. An ADR has a title, context, decision, status (proposed, accepted, deprecated or superseded) and consequences, including the negative ones and the alternatives rejected, and it is timestamped. It lives in the technical design and links to the concern or requirement it addresses.

Nov 5, 2026

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Interim definition. BLORP takes this term over when the global ontology lifts from Phase-0.

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Requirement

A statement of what the system must do, or the constraint it must respect, in the target state. It is written with one "shall", one subject (the system or a role) and one behavior, and carries an id, a type, a level, an owner role, a scope, a rationale, a source, a verification method with acceptance criteria, a priority, a phase and a lifecycle status.

Requirement attribute

A named field every requirement carries: id, title, statement, type, level, owner, scope, rationale, source, priority, phase, status, verification, validation, risk, medical flags, trace, and change history and baseline. Together the attributes are the requirement ontology of the Analysis Document Standard.

Requirement type

The kind of a requirement. One of: business, stakeholder, functional, quality, service-level, security, regulatory, constraint, architecture, interface, data, operation or risk-control.

Requirement level

Where a requirement sits in the decomposition. One of: business, stakeholder, system or software.

Owner role (requirement owner)

The requirement owner is a role taken from the role register, never a person. Every requirement has an owner role, such as the business owner, the PHI owner or the platform owner. A person's name appears only in the role register, as the current holder of the role.

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