PyPay/PYUSDPay

Problem

One of the biggest hurdles for new crypto users is understanding “gas.” In the real world, when you pay with a credit card, the fee comes out in the same currency you’re spending. On chain, that logic breaks. You use one token (like a stablecoin) for payments, but need a completely different asset (ETH) just to move it. That extra step is confusing and a major barrier to everyday use.

Solution

Think of this as Venmo, but for PYUSD, and it actually works without you paying gas fees. Users can send PYUSD to anyone without worrying about gas costs. That part is handled through our gas sponsorship. There is a reward system that gives users free transactions to try it out, then switches to a "1 in X" free model to keep users interested in using the app.

Note that even when a fee is taken, this fee is still in PYUSD and the user never has to worry about anything other than their use of the PYYSD stablecoin.

The app can also generate QR codes / links to request payments that are on-chain but are seamless.

I built PyPay as a gasless PYUSD payment system that tackles one of crypto's biggest UX barriers. The core challenge was making stablecoin payments feel like Venmo, without the confusing part that comes on chain like token authorization and needing eth for gas payments. Given that any app needs to make money somehow, even when there is a fee to pay the user will only ever pay it in PYUSD as well, never needing any other asset.

Obviously the app is focused on PYUSD. The gasless magic happens through EIP-7702 account abstraction. I use Privy for embedded wallets that can be upgraded to smart accounts, then Pimlico sponsors the gas fees. The user experience is seamless. They just connect with email, and I handle all the complexity behind the scenes.

I used Hardhat 3 extensively throughout development. It handled my smart contract deployment, testing, and verification (on Blockscount) on Sepolia. The new Hardhat 3 features made it incredibly smooth to iterate on my TransactionCounter contract and get it verified on Blockscout.

As for the hacky part, I built a smart tier system that gives users free transactions initially, then switches to a "1 in X" model to keep them engaged. The contract tracks usage and determines if transactions should be free or paid. All calculated off-chain for speed, then verified on-chain. The key is that the fee is also paid in PYUSD and sent as a batch transaction on chain.

The QR code generation for payment requests was a nice touch. Users can generate shareable links that pre-fill payment forms, making it easy to request payments from anyone.

Partner tech used: PYUSD, Hardhat 3, Blockscout