Bitnami Redis and PostgreSQL long term direction

Summary

GitLab chart bundles PostgreSQL and Redis subcharts from Bitnami to deploy PoC and demo envionments. These components are not meant for production usage, which we communicate in several channels. In the bast months Bitnami implemented several changes which make it difficult for us to continue using their charts and images, most importantly:

1. Changes to the build policy in December 2024, which hurts our ability to ship up to date images: https://github.com/bitnami/containers/issues/75671.
2. Changes to the tagging and repository in September 2025, where all tagged images will move behind a paywall: https://github.com/bitnami/charts/issues/35164. For migration purposes a legacy catalog is offered, but this one will receive no (security) updates and will eventually be dropped. Once dropped, only latest images will be available, which won't allow us to pull a specific PostgreSQL/Redis version.

We will need to decide on a long term strategy. Possible options are:

1. Replace Bitnami PostgreSQL and Redis with other vendor chart and images.
2. Drop Bitnami PostgreSQL and Redis with no replacement. All consumers will need to provision a external PostgreSQL/Redis.
3. Implement tooling for mirroring for predictable versions once the Bitnami legacy catalog was dropped.
4. Self build PostgreSQL and Reids images: The Bitnami sources are still available as Apache 2, so we can self-build and distribute these images. (this should be reviewed by legal to be sure).

Replacement Options

PostgreSQL

• Operator based alternatives:
  • cnpg: https://github.com/cloudnative-pg/cloudnative-pg
  • zalando postgres: https://github.com/zalando/postgres-operator
• ?

Redis

• Official valkey chart (does not exist yet but discussed in https://github.com/valkey-io/valkey/issues/2371#issuecomment-3264611542)

Acceptance Criteria

• Decided on a long term strategy for PostgreSQL and Redis in GitLab chart
• Create follow ups to implement and communicate that strategy