# Component-Based Architecture

> A convention of building a system from components that declare what they export and what they require.

Record: `architecture:component-based-architecture`
Kind: style
Layer: [Structural Core](https://banes-lab.com/records/layer/structural-core.md)
Severity: recommended
Scope: component, system
Canonical: https://banes-lab.com/ontology#architecture-component-based-architecture

Listed in [Architecture principles](https://banes-lab.com/api/records/architecture.md), after [Layered Architecture](https://banes-lab.com/records/architecture/layered-architecture.md) and before [Package by Feature](https://banes-lab.com/records/architecture/package-by-feature.md).

## Repair

- Refactored by: Extract Component, Define Contract
- Detected by: boundary import violations
- Violated by: component internals accessed externally
- Measured by: component cohesion/coupling
- Enforced by: component ownership rules

## Requires

- [Component Boundaries](https://banes-lab.com/records/lexicon/component-boundaries.md)
- [Contracts](https://banes-lab.com/records/lexicon/contracts.md)

## Reinforces

- [Modularity](https://banes-lab.com/records/architecture/modularity.md)
- [Composability](https://banes-lab.com/records/architecture/composability.md)

## Enables

- [Reuse](https://banes-lab.com/records/lexicon/reuse.md)
- [Replaceability](https://banes-lab.com/records/architecture/replaceability.md)

## Conflicts with

- [Big Ball of Mud](https://banes-lab.com/records/architecture/big-ball-of-mud.md)

## In tension with

- [Integration Overhead](https://banes-lab.com/records/lexicon/integration-overhead.md)

## Tensions

- [Component-Based Architecture / Integration Overhead](https://banes-lab.com/records/tension/component-based-architecture-integration-overhead.md)

## Severity

- [recommended](https://banes-lab.com/records/vocabulary/severity-recommended.md)

## Category

- [Codebase / System Architecture Styles](https://banes-lab.com/records/architecture-category/codebase-system-architecture-styles.md)

## Enforced by

- [rules/eslint/require-component.eslint.rule.ts](https://banes-lab.com/source/governance/rules/eslint/require-component.eslint.rule.ts.md)

## Linked from

- [Anti-patterns](https://banes-lab.com/ontology/principles/architecture-category-anti-patterns.md)
- [Core Modular Design](https://banes-lab.com/ontology/principles/architecture-category-core-modular-design.md)
- [Codebase / System Architecture Styles](https://banes-lab.com/ontology/lexicon/lexicon-category-codebase-system-architecture-styles.md)
- [Core Vocabulary](https://banes-lab.com/ontology/lexicon/lexicon-category-core-vocabulary.md)
- [Severity levels](https://banes-lab.com/ontology/schema/the-vocabulary-severity.md)
- [The resolutions](https://banes-lab.com/ontology/schema/the-resolutions.md)