Minimus Registry Shutdown: Migrate to Docker Hardened Images with Free Docker Assistance

Docker is officially sunsetting its Minimus registry on October 22. Developers relying on Minimus for small, minimal container images must migrate to Docker Hardened Images before the deadline to avoid service disruption. Docker is stepping up with free migration assistance and clear guidance to ease the transition.

The migration path is straightforward but requires action. Docker provides a dedicated migration tool and documentation to help you move your existing images and update your CI/CD pipelines. Here are the concrete changes you need to know:

Registry endpoint change: Switch all references from minimus to Docker Hardened Images via the new registry URL. Update your docker pull commands to point to docker.io/library/hardened-* (or the exact namespace provided in the migration docs).
Image tagging updates: Replace minimus/* tags with hardened/* tags. Use the docker tag command to retag local images and then push them to the new registry with docker push.
New image features: Docker Hardened Images offer enhanced security with built-in vulnerability scanning, smaller footprint (some images under 10 MB), and FIPS-compliant variants for regulated environments. These features are not available in Minimus.
Free migration tooling: Docker has released a docker-minimus-migrate CLI tool that automates the migration. Run docker-minimus-migrate --source minimus --target hardened to transfer images and rewrite Dockerfiles automatically. Docker support is also offering free one-on-one migration sessions until October 15.
Breaking changes in Dockerfiles: Your existing Dockerfiles referencing FROM minimus/* must be updated to FROM hardened/*. The --platform flag is still supported, but environment variables like MINIMUS_ARCH are deprecated; use TARGETARCH instead.

Why does this matter? If you ignore the shutdown, your builds will fail after October 22, potentially breaking production deployments. Migrating early gives you access to more secure, hardened images that align with modern security best practices. Docker’s free tools reduce the overhead, so you can focus on your code, not infrastructure.

Act now—schedule your migration, update your pipelines, and take advantage of Docker’s support before the clock runs out.

Source: https://www.docker.com/blog/moving-from-minimus-to-docker-hardened-images/