I just learned GitHub has new built-in artifact attestation (English page).

The docs do in no word mention the term SLSA there. (Instead they often talk about the SBOM - the "software bill of materials", you never mention in your docs AFAIK)

However, I also read this blog post from 2024 where they claim this artifact attestation is based on SLSA.

Now we have introduced SLSA without their cool GitHub actions mentioned in the docs and instead basically followed your official website doc/guide using this generic generator.

The GitHub doc basically relies on this GitHub action: https://github.com/actions/attest-build-provenance
There the only mention of SLSA is:

Attestations bind some subject (a named artifact along with its digest) to a SLSA build provenance predicate using the in-toto format.

What I take away from all that

As such, it seems this belongs together/builds up each other.
Also, i seems, the GitHub workflow is the modern (thus likely recommend?) way to generate attestations.

Actions I'd propose

However,:

• Your official SLSA docs here do not mention this at all. This can lead to confusion whether these are some competing "standards" or so.
• You don't have much influence on this, but IMHO, the GitHub docs should also more clearly state and maybe backlink to the SLSA docs.