Four steps. No prerequisites. No glossary. You'll have a working receipt before we explain what's happening underneath — each one anchored on H33-74 — the portable 74-byte commitment to the full post-quantum proof behind it.
When you finish step 4, you'll have a receipt. That's the win.
Pick a tier. Get an API key. Sandbox is free and good enough for the next three steps. Upgrade later if you need volume.
One HTTPS call. Your data in, your receipt out. The portable part is a 74-byte handle that commits to the full post-quantum proof.
Hand the receipt to the verifier. The verifier doesn't need an H33 account. It doesn't need to call us. It works offline. The verifier's result is the last step (independent verification of production receipts is not yet available).
Now we'll explain what that actually means ↓
You finished the artifact first. This is the part where the technology gets a name.
You generated a verifiable receipt. It contains a cryptographic commitment to your data. If even one bit changes, the receipt fails verification.
That's the difference between "we logged it" and "you can prove it."
Underneath: H33-74 (the receipt format), HATS (the continuous evidence layer), and the three-family post-quantum signature design (ML-DSA, FALCON, SLH-DSA; not yet available in production). One of those signature families being broken doesn't break the receipt. You don't need to know any of this to use it.
One thing. Wire receipts into the next system you'd like to be able to prove worked. An AI decision, a payment, a credential issuance, a data transformation. The receipt is the same shape for all of them.