Buildpacks Paketo UBI8 Tracking

[BarDweller]

Paketo uses Ubuntu as it's OS of choice, this means the Paketo Builder images all use Ubuntu, and the Run images, on which the built application is based, also use Ubuntu. Paketo are aware of the demand for UBI8 based images, and as mentioned on their 2022 roadmap, are interested in having a 'full suite' of images that use UBI8 https://blog.paketo.io/posts/2022-roadmap/

Some discussion of Paketo & UBI was made by the Shipwright team back in 2020, shipwright-io/build#302 where they identified at least one place where the choice of UBI8 over Ubuntu ran into issues. However, it's worth noting that the issue there was related to use of non rpm/dnf installed dependencies within a UBI8 container.

With Paketo being interested in offering UBI8 images, there is now scope to build such images within the Paketo project itself, and as part of that to attempt to address any issues that are found with Paketo packaged buildpacks.

When the Dockerfile RFC concludes, then there will be scope to offer a UBI8 based Paketo builder image that installs such dependencies via rpm/dnf, which would likely be a preferred option for customers who require supported applications.

Additionally, Liberty have offered a Paketo buildpack and offer manual instructions to allow the end user to create their own builder & run images based around UBI8 .. this would be redundant once Paketo offers UBI8.

We will need to author an RFC for Paketo to explain what we are suggesting for UBI8 support, and get that approved, and then do any necessary work, to enable the production of Paketo built UBI8 based builder/run images.

This issue will track that progress, although this is really blocked behind the Dockerfile RFC work, as the presence of extensions able to install rpm/dnf dependencies will greatly affect what the RFC can suggest/implement.