Business rule
A business rule is a domain-specific policy, condition, or constraint that governs valid data, decisions, actions, or behavior in an organization or its systems.
BDD in Action, Second Edition
A business rule is a constraint, policy, or decision rule that governs how a business process or system should behave.
- How it is used
- Clarifies expected feature behavior through conversations among business stakeholders, developers, and testers.
- How deep it goes
- Works through rule discovery, counterexamples, tabular variations, and focused executable scenarios, then separates business outcomes from automation mechanics.
- Examples
- Uses eligible and ineligible past flights, frequent-flyer points, hotel-distance searches, and account-registration constraints.
- What you can do after
- Practice/perform collaborative rule discovery, then express agreed outcomes as focused examples and verifiable scenarios.
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Building User-Friendly DSLs
A declarative statement expressing a policy, constraint, or decision condition for a business domain.
- How it is used
- Expresses domain policies and pricing logic so a Runtime can compute values such as rental discounts.
- How deep it goes
- Defines rule structure, models it in an AST, type-checks conditions, and translates separate rules to JavaScript execution.
- Examples
- Uses Rental rules that add discounts for a Saturday-containing period and for a rental starting in December.
- What you can do after
- Build it from scratch by attaching typed condition-and-consequence rules to record types and generating Runtime behavior.
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Simple Object-Oriented Design: Create clean, maintainable applications
A business rule is a domain-specific condition or policy that determines how an application should make decisions or perform business operations.
- How it is used
- Validates domain operations while preventing business complexity from accumulating in entities, services, or large methods.
- How deep it goes
- Works through validator and service responsibilities, then discusses generalizing rules and separating retrieval from execution without prescribing a single abstraction.
- Examples
- Uses training registration checks for capacity, repeat attendance, and duplicate enrollment, plus discount-rule growth and author-name generalization.
- What you can do after
- Apply it via a dedicated validator or rule class when an operation requires complex, cross-entity business decisions.
Inside AI
A business rule is a declarative condition or constraint that specifies an organizational decision or action for particular circumstances.
- How it is used
- Automates organizational decisions in domains such as finance, healthcare, taxation, and vehicle safety.
- How deep it goes
- Defines conditional rules and outlines repositories, authoring environments, and coherence checking without detailing full implementation.
- Examples
- Uses loan approval, hospital admission, taxation software, and self-driving vehicle safety as concrete applications.
- What you can do after
- Operate/configure centralized rules that automate decisions and support business-user authoring, modification, and testing.
Related concepts
- contextpart of · Context is the surrounding information, state, or circumstances that condition how an entity, event, or task is interpreted or how a system behaves.
- business logickind of · Business logic is the domain-specific rules, computations, and decisions that determine how a software system behaves and processes operations.
- scenarioused by · A scenario is a concrete description of a situation or conditions, often including actions and expected or possible outcomes, for analysis or evaluation.
- acceptance criteriaequivalent to · Acceptance criteria are verifiable conditions that a requirement, feature, or deliverable must satisfy to be considered acceptable or complete.
- Example Mappingused by · Example Mapping is a collaborative technique that organizes user stories, rules, examples, and questions to clarify requirements and expected behavior.
- record typepart of · A record type is a classification describing the structure, kind, and semantic role of records within a data format or system.
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