Hi @eleimt 
and welcome to passbolt community forum 
Can you tell me more about balena.io ? If I understand well, it is a cloud where you can deploy docker images on small machines such as raspberry, and arm-based ?
The official passbolt docker image is currently amd64-only. We already had this request here and if needed, you can try this community passbolt docker image, I created it based on our passbolt docker repository.
In a few lines, I built it like this:
# Clone of the passbolt_docker repository
git clone git@github.com:passbolt/passbolt_docker.git
# Go to the passbolt_docker repository
cd passbolt_docker
# Build time !
# 3.5.0-ce-multiarch
docker buildx build --build-arg PASSBOLT_REPO_URL=https://download.passbolt.com/ce/debian --build-arg PASSBOLT_PKG=passbolt-ce-server --build-arg PASSBOLT_FLAVOUR=ce --build-arg PASSBOLT_COMPONENT=stable -t anatomicjc/passbolt:3.5.0-ce-multiarch --push --platform linux/amd64,linux/arm64/v8,linux/arm/v7,linux/arm/v6,linux/386 -f debian/Dockerfile .
# latest-ce-multiarch
docker buildx build --build-arg PASSBOLT_REPO_URL=https://download.passbolt.com/ce/debian --build-arg PASSBOLT_PKG=passbolt-ce-server --build-arg PASSBOLT_FLAVOUR=ce --build-arg PASSBOLT_COMPONENT=stable -t anatomicjc/passbolt:latest-ce-multiarch --push --platform linux/amd64,linux/arm64/v8,linux/arm/v7,linux/arm/v6,linux/386 -f debian/Dockerfile .
# 3.5.0-ce-non-root-multiarch
docker buildx build --build-arg PASSBOLT_REPO_URL=https://download.passbolt.com/ce/debian --build-arg PASSBOLT_PKG=passbolt-ce-server --build-arg PASSBOLT_FLAVOUR=ce --build-arg PASSBOLT_COMPONENT=stable -t anatomicjc/passbolt:3.5.0-ce-non-root-multiarch --push --platform linux/amd64,linux/arm64/v8,linux/arm/v7,linux/arm/v6,linux/386 -f debian/Dockerfile.rootless .
# latest-ce-non-root-multiarch
docker buildx build --build-arg PASSBOLT_REPO_URL=https://download.passbolt.com/ce/debian --build-arg PASSBOLT_PKG=passbolt-ce-server --build-arg PASSBOLT_FLAVOUR=ce --build-arg PASSBOLT_COMPONENT=stable -t anatomicjc/passbolt:latest-ce-non-root-multiarch --push --platform linux/amd64,linux/arm64/v8,linux/arm/v7,linux/arm/v6,linux/386 -f debian/Dockerfile.rootless .
Cheers,