Update one package in your container image and watch your users re-download 500MB of unchanged content. Traditional Dockerfile layers are instruction-based—a single package update invalidates an entire layer.

This talk introduces chunkah, a tool that post-processes container images into content-based layers. Files are grouped by package, not Dockerfile structure. Update one package, users download only that layer.

We'll cover:

• Why instruction-based layers hurt pull performance (with numbers)
• How content-based splitting works under the hood
• Live demo: chunkah in action, before/after comparison
• How podman history reveals package-to-layer mapping

From Project Hummingbird, where we run 70+ production container images with chunkah, we'll show real metrics on bandwidth savings and how to adopt this in your own builds.

Audience: Container image builders, CI/CD engineers, registry operators, anyone who's wondered why their image pulls are so slow.