Monday, October 28, 2024

Bitnami Helm charts moving to OCI

In January 2022, we announced the general availability of Helm charts in OCI registries, coinciding with the release of Helm version 3.8.0. In January 2023, Bitnami began populating and distributing the largest and most up-to-date Open-Source catalog of Helm charts in OCI format in Docker Hub

Since then, the adoption of the Bitnami Helm charts in OCI format has proliferated. Because charts stored in container registries follow OCI standards, developers can use many of the same tools for Helm charts that they use with container images. This makes integrating Helm into automated pipelines easier and uses modern infrastructure-as-code and deployment techniques like GitOps.

We would like to go further and help the Helm community to continue adopting the OCI distribution format. Starting November the 18th, 2024, Bitnami Helm charts will default to OCI. All the charts will remain Open Source and publicly available at https://hub.docker.com/u/bitnamicharts.

Why OCI Format?

1. Standardization and Interoperability

The OCI format offers a standardized way to package and distribute container images and related artifacts. This standardization fosters interoperability across different tools and platforms, making it easier for developers and operators to collaborate. By adopting OCI, Helm charts can seamlessly integrate with existing container ecosystems, enhancing compatibility with tools like Docker and container registries.

2. Enhanced Security

The OCI format promotes best practices for image signing and verification, allowing users to validate the integrity of their deployments. By adopting OCI, the Bitnami Helm charts leverage these security features. This ensures that the charts we publish are trustworthy and resilient against vulnerabilities.

3. Improved Distribution

With OCI-compliant registries becoming increasingly prevalent, moving to the OCI format allows for more efficient distribution of Helm charts. Users can store and manage Helm charts alongside container images in a single repository, simplifying workflows and reducing the complexity of multi-repository management.

4. Future-Proofing Our Ecosystem

The cloud-native landscape is dynamic, with new technologies and practices constantly emerging. By transitioning to the OCI format, Bitnami Helm charts are delivered in a way that sets developers up for success in this ever-changing environment.


The move to OCI format is more than just a technical shift; it’s an opportunity for the Helm community to enhance its capabilities, improve security, and simplify our workflows.

What will happen to the current index.yaml stored at charts.bitnami.com?


In order to guarantee a smoother transition, the index.yaml will continue existing as an OCI artifact in Docker Hub. Any users who still use the helm repo add command can continue using this approach to maintain backward compatibility. The Helm tooling manages this in a transparent manner.

The index.yaml will change the “URL” option to point to the new OCI versions of Helm charts:

   urls:

-    - https://charts.bitnami.com/bitnami/airflow-18.3.2.tgz

+   - oci://registry-1.docker.io/bitnamicharts/airflow:18.3.2


Users should not see any change for deploying Helm charts. The requirement is to use a Helm CLI greater than 3.8.0 to deploy them.

What will happen to the Bitnami Helm charts in tgz format?

The Bitnami Helm charts in tgz format will no longer be updated. Previous versions since 2023 are available at Docker Hub and it is easy to get the tgz format via Helm command:


    $ helm pull oci://registry-1.docker.io/bitnamicharts/airflow –version 18.3.2


Older versions will continue to be available at the same URL for 6 months to ensure a smooth transition. Do not hesitate to contact us for any questions or suggestions at https://github.com/bitnami/charts/issues.