It is almost 100% compatible with docker. I only had to do minimal changes in my Dockerfiles to use it.
Buildah (`podman buildx`, `buildah bud --arch arm64`) just gained multiarch build support; so also building arm64 containers from the same Dockerfile is easy now. https://github.com/containers/buildah/issues/1590
IDK what BuildKit features should be added to Buildah, too?
Cache mounts are what we rely on for incremental rebuilds.