# Domain Core

> The requirement that pure domain logic occupy the core, isolated from external concerns.

Record: `lexicon:domain-core`
Kind: constraint
Layer: [Structural Core](https://banes-lab.com/records/layer/structural-core.md)
Canonical: https://banes-lab.com/ontology/lexicon#lexicon-domain-core

Listed in [Lexicon terms](https://banes-lab.com/api/records/lexicon.md), after [Dependency Rule](https://banes-lab.com/records/lexicon/dependency-rule.md) and before [Layer Separation](https://banes-lab.com/records/lexicon/layer-separation.md).

## Category

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

## Required by

- [Hexagonal Architecture](https://banes-lab.com/records/architecture/hexagonal-architecture.md)

## Linked from

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