buildah

buildah command [options]

buildah is a tool for building OCI and Docker container images without requiring a daemon. It provides fine-grained control over image layers and can build from Dockerfiles or through direct manipulation of containers.Unlike Docker, buildah does not require a background daemon process, making it well-suited for CI/CD pipelines and restricted environments. It supports rootless builds, where the entire build process runs without elevated privileges. As part of the Podman ecosystem, it shares storage and image formats with podman and skopeo, allowing seamless interoperation between the tools.

build (formerly bud)

Build image using Containerfile/Dockerfile

Create working container

Run command in container

Save container as image

Push image to registry

Pull image from registry

List images

List working containers

Copy files into container

Set image configuration (cmd, entrypoint, env, labels, etc.)

Remove container

Remove image

Display detailed information

Mount container filesystem

Unmount container filesystem

/etc/containers/registries.conf

Registry configuration including mirrors, insecure registries, and search order.

Storage driver and location settings for images and containers.

Image signature verification policy.

From Containerfile/Dockerfile:

$ buildah build -t myapp:latest .

$ # Create container
ctr=$(buildah from fedora)

# Install packages
buildah run $ctr dnf install -y nginx

# Copy files
buildah copy $ctr ./app /app

# Set config
buildah config --cmd "/app/start.sh" $ctr

# Commit
buildah commit $ctr myapp:latest

- Daemonless operation- Rootless builds- Dockerfile compatibility- Fine-grained layer control- OCI image format- Multiple storage backends- Script-friendly

Different from Docker workflow (learning curve). Some Docker features not supported. Rootless mode has kernel and filesystem limitations. Storage configuration important. The bud subcommand is deprecated in favor of build.

buildah was created by Red Hat around 2017 as a component of their container tooling suite, focusing on building without daemons.

podman(1), docker(1), skopeo(1)