A partner sale request comes in, the gateway authenticates and normalizes it, resolves routing, routes the capture through its CyberSource connection, computes fees, and attaches a tamper-evident proof, all in one response. PaychainX is the orchestration and proof layer; CyberSource is the connected processor, Propelr the pilot partner, and Zero Hash the stablecoin settlement provider. Below are the real artifacts captured from the running gateway.
When a customer pays, PaychainX is the layer between the store and the bank. It checks the payment is legitimate, sends it to the card network to collect the money, works out the fees, and then writes a sealed digital receipt for that exact transaction.
That receipt is a fingerprint. If anyone later changes a single detail, the fingerprint no longer matches, so tampering is obvious. Banks and auditors can check it themselves without trusting us. The post-quantum work future-proofs that seal so it stays trustworthy against tomorrow's quantum computers.
For the technical reader, every claim above is backed by the real request, response, and proof artifacts below. For everyone else, that is the whole story: take payments, prove each one, keep the proof valid for the long run.
API key header, JSON body. Schema validated before any downstream call.
Zero Trust: every hop re-validates the request and merchant context. A bad key fails fast with 401.
Terminal, device, store, lane, operator, and session metadata normalized into one canonical request.
Routing policy, approved processors, MID, and volume thresholds resolved on the hot path.
Decision, score, and flags, plus normalized AVS and CVV so merchant logic is processor-independent.
Stored-credential token captured through a uniform adapter that returns a canonical result.
Gross, fee (bps plus fixed), and net computed by the gateway, not the processor.
Canonical result is digested into a proof_id and proof_hash, submitted, and queued for the immutable archive. Runs in parallel, never blocks the capture.
Processor-agnostic payment object with pq_proof and fees attached. Same shape regardless of processor.
Partner sale. The API key is server-side only and never exposed. Token is a non-PAN stored-credential reference.
Processor-agnostic payment object. No PAN, no CVV value, no PII.
Each captured payment binds a SHA-256 digest to its full canonical content. Identical canonical inputs reproduce the same hash; changing any field changes it. These are real proof hashes observed across live runs.
Two runs with the same amount (11111) but different reference and terminal context produce different hashes, which proves the digest binds the full canonical content, not just the amount. That is the property an auditor needs: recompute the digest from the archived canonical result and it must match, independent of the processor report.
Anyone can verify a proof without trusting the processor report.
The proof record already reserves the signature and signature_algorithm fields, so the post-quantum upgrade is drop-in and does not change the envelope merchants integrate against.
All require authentication. A bad key returns 401.
Production end-to-end time includes the Cloudflare edge and the live CyberSource round trip; gateway-only compute is sub-3 ms.
Legacy processors process transactions. PaychainX processes, orchestrates, verifies, and audits them.