# Image Extension Specification

**Canonical:** https://apis.io/apis/buildpacks-io/image-extension-spec/  
**Provider:** buildpacks-io — https://apis.io/providers/buildpacks-io/  
**Documentation:** https://github.com/buildpacks/spec/blob/main/image_extension.md

Image Extension Specification is one of 8 APIs that [buildpacks-io](https://apis.io/providers/buildpacks-io/) publishes on the [APIs.io](https://apis.io/) network. Tagged areas include Cloud Native Buildpacks, Image Extension, Dockerfile, and Specification. The published artifact set on APIs.io includes API documentation.

Image extensions emit Dockerfile snippets applied by the `extender` lifecycle binary to the build and/or run image. Share the buildpack surface (extension.toml, bin/detect, bin/generate) but produce Dockerfile output instead of layers — enabling base-image customization (apt packages, native libs) inside a buildpacks workflow.

## Machine-readable artifacts (2)

- **Documentation** — https://github.com/buildpacks/spec/blob/main/image_extension.md
- **Repository** — https://github.com/buildpacks/spec

## Other buildpacks-io APIs (7)

- [Buildpack Specification](https://apis.io/apis/buildpacks-io/buildpack-spec/)
- [Platform Specification](https://apis.io/apis/buildpacks-io/platform-spec/)
- [Distribution Specification](https://apis.io/apis/buildpacks-io/distribution-spec/)
- [Project Descriptor (project.toml)](https://apis.io/apis/buildpacks-io/project-descriptor-spec/)
- [Service Bindings Extension](https://apis.io/apis/buildpacks-io/service-bindings-spec/)
- [buildpacks-io Buildpacks API](https://apis.io/apis/buildpacks-io/buildpacks-io-buildpacks-api/)
- [buildpacks-io Search API](https://apis.io/apis/buildpacks-io/buildpacks-io-search-api/)

## Tags

Cloud Native Buildpacks, Image Extension, Dockerfile, Specification

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Profiled by [API Evangelist](https://apievangelist.com) and published on [APIs.io](https://apis.io/apis/buildpacks-io/image-extension-spec/). The API's provider profile, Kin Score and agent-readiness rating are at https://apis.io/providers/buildpacks-io/.