Overview

Zepay is a gasless USDC payment app built on Sonic. It is designed to feel like a normal Web2 app – sign in with email, tap to send, tap to earn – while your funds stay on‑chain in a non‑custodial SmartAccount and PersonalVault that you control.

Under the hood, Zepay uses:

• A SmartAccount (smart‑contract wallet) for each user

• A per‑user PersonalVault for Earn (yield via Aave)

• An AaveYieldProvider contract that connects vaults to Aave v3 on Sonic

• A UsernameRegistry that maps @handles to SmartAccounts

• A Privy EOA as your email‑based owner wallet

You never see seed phrases, RPC URLs or gas. You just see USDC, an earning balance, and a clean, Web2‑like interface.

Core idea

Web2 convenience (email login, no pop‑ups, no gas) with Web3 custody (your funds always on‑chain, recoverable even if Zepay disappears).