Over the past year, builders based on Universal Base Image (UBI) 9 and UBI 10 have been published to Paketo Buildpacks. You can build applications on Red Hat Enterprise Linux (RHEL) 9 and RHEL 10 using Paketo buildpacks.

In this post we show where those builders live on GitHub and Docker Hub, and we build a sample Node.js application with the UBI 9 and UBI 10 builders.

Repositories and container images

For UBI 9

All UBI 9 builder source code lives in github.com/paketo-buildpacks/ubi-9-builder. Published images on Docker Hub are:

• paketobuildpacks/ubi-9-builder (includes the buildpacks and extensions needed to build an application; currently only Node.js is supported)
• paketobuildpacks/ubi-9-builder-buildpackless (no buildpacks included)

You can find the base images that each builder uses in the release notes of the ubi-9-base-images repository.

For UBI 10

UBI 10 follows the same pattern: builder source code is in github.com/paketo-buildpacks/ubi-10-builder, and published images are on Docker Hub:

• paketobuildpacks/ubi-10-builder (includes the buildpacks and extensions needed to build an application; currently only Node.js is supported)
• paketobuildpacks/ubi-10-builder-buildpackless (no buildpacks included)

UBI 10 base images are listed in the ubi-10-builder release notes.

Build a Node.js application with Podman/Docker and UBI 9 or 10 builders

We assume the host operating system is Fedora Linux; the steps are the same on other supported OSes, and links are included where installation differs.

Before we build our application, we want to ensure the following tools are installed and configured. The instructions for configuring Podman where we describe below, are based on the instructions from the Cloud Native Buildpacks (CNB) project.

Installing and configuring Podman

Use Podman version 5.1.0 or newer.

Note: To install Podman on another OS, follow the Podman installation instructions.

Expose the service using systemd:

systemctl enable --user podman.socket
systemctl start --user podman.socket

Route the Docker CLI to Podman:

export DOCKER_HOST="unix://$(podman info -f "{{.Host.RemoteSocket.Path}}")"

Installing Docker

If you use Docker Engine instead of Podman, install it from the Docker Engine install documentation. No further configuration is needed beyond what that documentation describes.

Installing and configuring Pack CLI

On Fedora:

dnf install pack

Note: To install the Pack CLI on another OS, follow the CNB project instructions under Install pack.

Enable experimental options in the Pack CLI when using UBI builders; the Node.js extension is still experimental.

pack config experimental true

Building a Node.js application

You need a builder and an application. This walkthrough uses the Paketo samples repo; any Node.js application will work.

git clone https://github.com/paketo-buildpacks/samples

Build with pack and the UBI 9 builder:

pack --docker-host=inherit build nodejs-app \
--builder index.docker.io/paketobuildpacks/ubi-9-builder \
--path ./samples/nodejs/npm

To use the UBI 10 builder instead, pass --builder index.docker.io/paketobuildpacks/ubi-10-builder.

When the build finishes, the logs should include:

Successfully built image nodejs-app

You should then see your Node.js app image in your Podman or Docker image list.

Run the application with Podman

podman run -d -p 8080:8080 nodejs-app`

or Docker (pick one)

docker run -d -p 8080:8080 nodejs-app`

Verify the application responds:

curl http://localhost:8080

If you receive HTTP/1.1 200 OK, the application is running.

Conclusion

If you would like to contribute under the Paketo implementation of CNCF buildpacks, feel free to take a look on the community instructions on how to get involved or check out this blog post on the topic.

Happy building!