Artisan Hub 237 Certification Authority

Verify a certificate yourself

The signed message is rebuilt from the fields printed on the certificate, newline-separated, in exactly this order:

ah237.certificate.v1
<type>            # coa, otc, prc or avc
<certificate number>
<content hash>
<issue date, ISO 8601>

Then check the detached signature against the public key. For example:

# Python, with PyNaCl
from nacl.signing import VerifyKey
import base64

def b64u(s): return base64.urlsafe_b64decode(s + '=' * (-len(s) % 4))

key = VerifyKey(b64u("87S7snKy7fKiLbc_SPLnShYfTOQ0J4J0l0f_PjPDJwg"))
payload = "\n".join([
    "ah237.certificate.v1", "coa",
    certificate_number, content_hash, issued_at_iso8601,
]).encode()

key.verify(payload, b64u(signature))   # raises if invalid

The full hashes and the exact issue date are shown on each certificate’s verification page.

Tamper-evident certificate log

Every certificate lifecycle event — issued, approved, revoked, verified — is appended to a hash chain in which each entry commits to the one before it. Altering or removing any past entry breaks every link after it.

Entries verified

1

Chain state

Intact