You can sign-in as a non-government user (though they also have CAC support for federal govt users). There's built-in document/identity proofing as well but the

You can sign-in as a non-government user (though they also have CAC support for federal govt users). There's built-in document/identity proofing as well but there are some extra requirements to get that enabled on an application. You do need to be working with the government to integrate with Login.gov though (but it's just OIDC on the backend)