Container-native images

[korewaChino]

Let's start building Ultramarine in a container-native way!

Instead of building individual rootfs images from scratch in our build pipeline everytime, let's take advantage of OCI images and layering.

We build root fs images and pack them inside an OCI container, which also double as fully native bootc images. And for normal distribution, we can simply just pull down those OCI images, artifacts such as EROFS images, disk images, and interactive installer (ISO9660) images out of them for normal usage.

This brings on many benefits:

• Greatly reduces the scope surface of Katsu, turning it into a simple artifact packer that simply just packs those OCI images into bootable disk images, ready to use
• Extends the previous experiment with bootc (https://github.com/Ultramarine-Linux/bootc), superseding it.
• Greatly reduces build times, as we never have to redownload and rebuild images from scratch
• Allows us to reuse base images, deriving them into other spins easily, and making custom remixes trivial to create (see point above)
• These images can also be directly booted off a bootc installation, other than simply being a container for the rootfs
• Gives us an easy way to simply distribute the root FS itself bare, without any partition layout or assumptions about bootloader/environment

An implementation is underway the the ng branch of the bootc repo.

[linear]

FYRA-383

[korewaChino]

Also this means that bootable ISO images built in this manner can be installed in either bootc or standard mode, which makes our install flow INCREDIBLY streamlined, one ISO for both mutable and immutable installs.

Adding this here so I don't forget the additional bonus

[korewaChino]

thinking it would be cool to do some kind of build matrix tree just generating jobs with dependencies and stuff

tree:
    - name: base
      derivatives:
      - name: gnome
        derivatives:
         - anaconda
         - readymade
      - name: plasma
        derivatives:
         - anaconda
         - readymade
      - name: flagship
        derivatives:
         - anaconda
         - readymade
         - surface
         - idk
      - name: xfce
        derivatives:
         - anaconda
         - readymade

[tulilirockz]

Please do not use compose files, use the same pattern as what fedora-bootc upstream is using https://gitlab.com/redhat/centos-stream/containers/bootc/-/tree/c10s?ref_type=heads

[korewaChino]

Please do not use compose files, use the same pattern as what fedora-bootc upstream is using https://gitlab.com/redhat/centos-stream/containers/bootc/-/tree/c10s?ref_type=heads

we're not gonna use rpm-ostree compose files

[korewaChino]

remind me to put this in the roadmap for 44

[korewaChino]

Seems like this experiment is a success, we can start porting our live scripts to the new bootc environment now :3

I just tested building the image with Katsu and it works pretty much flawlessly, Even better with EROFS deduplicating the blocks so our images are still roughly the same size as before. I think this is stable enough that we can start build the same identical image entirely in OCI as a bootc image