Building for the ARM architecture is now easier than ever! The heroku/builder:24 builder supports both AMD64 and ARM64 architectures, and includes multi-arch .NET, Go, Java, Node.js, PHP, Python, Ruby and Scala buildpacks. You can read more about Heroku’s Cloud Native Buildpacks here.

NOTE: Our current multi-architecture support allows building an ARM64 application image on an ARM64 host, and building an AMD64 application image on an AMD64 host. We do not currently support building an application image for one architecture on a different architecture. However, if your host machine supports emulation (e.g., with QEMU) you may be able to perform cross platform builds, albeit with a performance penalty.

1. Clone the samples repository

# clone the repo
git clone https://github.com/buildpacks/samples

2. Build the app

If you’re using an ARM64 computer (such as an Apple Silicon Mac, or an AWS Graviton instance), you can build an ARM64 OCI image with pack simply by setting your builder to heroku/builder:24:

pack build java-maven-sample --path samples/apps/java-maven/ --builder heroku/builder:24

By default, pack uses the current architecture for multi-arch builders like heroku/builder:24, so an AMD64 image will be built on AMD64 systems.

If you want to build an ARM64 image from a different host architecture, use the --platform parameter:

pack build java-maven-sample --path samples/apps/java-maven/ --builder heroku/builder:24 --platform linux/arm64

TIP: If you don’t want to keep specifying a builder every time you build, you can set it as your default builder by running pack config default-builder <BUILDER> for example pack config default-builder heroku/builder:24

3. Run it

docker run --rm -p 8080:8080 java-maven-sample

Congratulations!

The app should now be running and accessible via localhost:8080.

---