There's a discussion thread for email attestations here[1]. Those would support local builds.

But to take a step back: if you want attested builds because you think attestation is itself a gold star, then you're working from the wrong priors. Attestations do not imply that a package is secure any more than a hash does; what they are is a cryptographic signature over a set of claims, which allows for authenticated auditing of a project's state over time.

I think PyPI's documentation does a good job of conveying this nuance[2], and that much of the opprobrium of attestations comes from people either not understanding that nuance or imputing conspiracies into it.

[1]: https://github.com/pypi/warehouse/issues/18007

[2]: https://docs.pypi.org/attestations/security-model/#trustwort...