Concepts

What is a buildpack?

A buildpack is software that transforms application source code into runnable artifacts by analyzing the code and determining the best way to build it.

What is a builder?

A builder is an OCI image containing an ordered combination of buildpacks and a build-time base image, a lifecycle binary, and a reference to a runtime base image.

What is the lifecycle?

The lifecycle orchestrates buildpacks, then assembles the resulting artifacts into an OCI image. It does its work in a series of distinct “phases”.

Base image types

As you already know, Cloud Native Buildpacks (CNBs) transform your application source code into OCI images that can run on any cloud.

What is a composite buildpack?

A composite buildpack, also sometimes called a “meta buildpack”, is a buildpack that does not contain any ./bin/detect or ./bin/build binaries, but instead references other buildpacks in its buildpack.toml via the [[order]] array.

This is useful for composing more complex detection strategies.

What is an image extension?

An image extension is software that generates Dockerfiles that can be used to extend base images for buildpacks builds.