doc.wikimmedia.org would be a great place, but anywhere publicly accessible (gitlab pages?)

I'd assume we'd prefer doc.wikimedia.org as the canonical location of most Wikimedia-related documentation? I'm not sure pages was a planned, enabled feature for gitlab.wikimedia.org. Or if it's just on by default? Anyhow, in the engineering-all email, @thcipriani mentioned that there might be issues around a trusted build environment as it related to doc.wikimedia.org. I do believe there is some consensus that doc.wikimedia.org is already a less-trusted wikimedia.org domain, given its absence from $wgCrossSiteAJAXdomains, etc.

For mwbot-rs I'd like to publish coverage reports and generated rustdoc documentation.

IMO GitLab Pages should be enabled! Potentially even integrating it with Toolforge would be great; it’d allow for easier publishing of static sites on there, no SSH required.

There's https://toolhub.wikimedia.org/tools/toolforge-docs, though I'm not sure if it has any support for building on push, but might be extended for that I guess :) (cc. @Samwilson)

Building tool-docs on push could definitely be done! And in fact it's probably a better way to do things than the periodic checking all tools for a docs directory, as it does now. It's already got the beginnings of GitLab integration with the translation stuff (although that needs more work).