Currently, loading Nix and Guix as single origins with a huge snapshot, with each branch name being a URL is wrong.
We need to replace the Nixguix loader with a lister, which creates as many origins referenced by Nix and Guix public manifests.
This would be closer to what we do with Debian/Ubuntu.
Define the following (see the hedgedoc  which details a proposition):
- target structure sketch of the data in the archive
- What are the origin urls?
- what kind of extrinsic metadata and/or extids are we storing?
- what kinds of snapshots we're generating
- D8341: Implement lister
- [ ] D8406, ...: Adapt archive loader (package loader) to accept tarball from nixguix manifests (cannot work )
- D8581: Implement ContentLoader (possibly as a
package core loader) to deal with content file with intrinsic metadata (out of nixguix manifests)
- D8584: Implement DirectoryLoader (possibly as a
package core loader~~) to deal with tarball with intrinsic metadata (out of nixguix manifests)
- Update implementations ^ dealing with unsupported integrity hash (sha512)
- Run through docker
- Deploy in staging
- Call for public review
- Deploy in production when ok ^
 Draft pad: https://hedgedoc.softwareheritage.org/2AQFbVB0S-OrOtkJV2yNJw
 It cannot. We may not have any versions received and package loader are currently relying on that particular data for its main ingestion algorithm.