Index

+++ title="Write a basic extension" weight=2 aliases = [ "/docs/extension-author-guide/create-extension" ] +++

This is a step-by-step tutorial for creating and using image extensions, which allow for customization of the build-time and runtime base images using Dockerfiles.

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What we'll cover

• Setting up your local environment
• Why this feature?
• The building blocks of a Cloud Native Buildpacks image extension
• Extending the build-time base image with a build.Dockerfile
• Switching the runtime base image with a run.Dockerfile
• Extending the runtime base image with a run.Dockerfile

<a href="/docs/for-buildpack-authors/tutorials/basic-extension/01_setup-local-environment" class="button bg-pink"> Start Tutorial </a>