# Closed Core

> A core that cannot be extended without modifying its own source, so every addition edits the core.

Record: `lexicon:closed-core`
Kind: anti-pattern
Layer: [Extensibility Core](https://banes-lab.com/records/layer/extensibility-core.md)
Canonical: https://banes-lab.com/ontology/lexicon#lexicon-closed-core

Listed in [Lexicon terms](https://banes-lab.com/api/records/lexicon.md), after [Operational Duplication](https://banes-lab.com/records/lexicon/operational-duplication.md) and before [Direct Control Ownership](https://banes-lab.com/records/lexicon/direct-control-ownership.md).

## Category

- [Plugin / Extensibility / IoC](https://banes-lab.com/records/lexicon-category/plugin-extensibility-ioc.md)

## Negated by

- [Extension Points](https://banes-lab.com/records/architecture/extension-points.md)

## Linked from

- [Plugin / Extensibility / IoC](https://banes-lab.com/ontology/principles/architecture-category-plugin-extensibility-ioc.md)