container-snap: Atomic Updates from OCI Images using Podman’s Btrfs Driver (asg2025)

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Traditional package updates using tools like RPM or Zypper can introduce risks, such as incomplete updates or accidentally breaking the running system. To overcome these challenges, we developed **container-snap**, a prototype plugin designed to deliver atomic OS updates—updates that are fully applied or rolled back without compromising the system's state. container-snap leverages OCI images as the source for updates and integrates seamlessly with openSUSE’s [tukit](https://github.com/openSUSE/transactional-update) to enable transactional OS updates. By utilizing Podman’s btrfs storage driver, it creates btrfs subvolumes directly from OCI images, allowing systems to boot from the OCI image. This approach empowers users to construct their own OS images using familiar container image-building tools, like Docker or [Buildah](https://buildah.io/). In this session, we’ll dive into: - The architecture and technical implementation of container-snap - Challenges encountered during development and how we resolved them - Key lessons learned along the way - A live demo showcasing container-snap in action Come and join this session to learn more about how to boot from an OCI image without bricking your system! Licensed to the public under https://creativecommons.org/licenses/by/4.0/de/ about this event: https://cfp.all-systems-go.io/all-systems-go-2025/talk/YTCMSG/