Most "add crypto payments to my site" services integrate a custodial
gateway — NowPayments, Coinbase Commerce, BitPay. Your customers' funds
touch a third party's wallet before reaching yours. That's how every
crypto-payments-as-a-service company is built today: they take custody,
they get KYC'd, they need money-transmitter licenses, and they can
freeze your funds.
I do it differently. Direct wallet → wallet, on-chain, in one
transaction. The smart contract never holds the funds. There's no
intermediary to freeze, KYC, or rate-limit you.
I authored secudigate — an open-source, non-custodial
stablecoin payment gateway. 157 passing tests, MIT licensed, real
production architecture. The integration work I do for you is built on
the same pattern.
— What you get —
✔ Solidity payment contract (or embed of secudigate, your choice)
→ Atomic 3-transfer settlement: platform fee, optional merchant fee,
net to your treasury — all in ONE transaction
→ Replay protection (each invoice ID can only be paid once)
→ Optional per-payer daily caps in USD via Chainlink price feeds
→ OFAC sanctions screening via Chainalysis oracle (optional)
✔ Pay-page UI in React + wagmi + RainbowKit
→ Wallet connect (MetaMask, Rainbow, Coinbase, WalletConnect)
→ Auto network-switch prompts
→ Approve + Pay flow with real-time status
→ Mobile responsive
✔ Backend webhook handler
→ HMAC-signed delivery (or use secudigate's built-in dispatcher)
→ Idempotency via unique invoice IDs
→ Node.js or Python — your stack
✔ Working end-to-end on testnet (Sepolia)
→ Mainnet deploy in Premium tier
— What's NOT included —
✘ External security audit (separate service — happy to recommend firms)
✘ Mainnet gas costs (you pay the network fees)
✘ Hosting your backend / frontend (you provide the deploy target)
— Why I can do this —
I'm the author of secudigate — visit secudigate to see the same
architecture I'd implement for you, live on Sepolia, 157 passing tests including an
80-test adversarial suite. Currently lead developer at Kaaj Invest,
where I've built and operate 3 production crypto-adjacent products
solo.
Cyfrin Updraft–certified across the full Solidity track.
