buildpacks-io

Image Extension Specification

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.

GitHub

Documentation

📖
Documentation
https://github.com/buildpacks/spec/blob/main/image_extension.md

Other Resources

🔗
Repository
https://github.com/buildpacks/spec

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API entry from apis.yml

apis.yml Raw ↑ 
aid: buildpacks-io:image-extension-spec
name: Image Extension Specification
tags:
- Cloud Native Buildpacks
- Image Extension
- Dockerfile
- Specification
humanURL: https://github.com/buildpacks/spec/blob/main/image_extension.md
properties:
- url: https://github.com/buildpacks/spec/blob/main/image_extension.md
  type: Documentation
- url: https://github.com/buildpacks/spec
  type: Repository
description: 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.