github-actions-container-build

Multi-architecture container image builds in GitHub Actions use matrix workflows with native ARM64 runners for public repos or QEMU emulation for private repos. Podman executes platform-aware builds with --platform flags, creating separate digests per architecture that are combined into OCI-compatible manifests for registry push.

Yes. Podman supports rootless builds natively in GitHub Actions. The Skill provides workflow templates that implement rootless Podman with push-by-digest artifact flow, keeping registries clean while maintaining security and compatibility across public and private repository scenarios.

Native ARM64 runners execute ARM64 builds directly on hardware, offering faster builds but available only on public repositories. QEMU emulation runs on x86 runners via software translation, slower but accessible on private repos and free-tier accounts, with trade-offs in build time versus accessibility.

Push-by-digest workflow captures individual architecture digests during Podman builds, stores them as artifacts, then creates and pushes a manifest that references those digests to the registry. This approach prevents intermediate layers from cluttering the registry and enables clean multi-arch image organization.

The Skill defaults to GitHub Container Registry (GHCR) but includes optional workflow templates for Docker Hub integration. Both registries support OCI-compatible manifests and push-by-digest workflows, with template customization enabling registry selection based on your deployment requirements.