When we added crypto top-ups to VerifDoc, many customers in South Asia asked for one thing: USDT on Tron (TRC-20) . It's what they hold on exchanges, and network fees are a few cents. Here's how we accept it without a payment processor, and the checks that stop us from crediting money that never arrived. The shape of it We keep a small pool of Tron wallets. A customer starts a deposit, gets a wallet and an amount, and sends USDT. A scanner asks TronGrid for TRC-20 transfers ...