2Settle — a crypto-to-fiat payment engine I built (Node.js/TypeScript). Users pay in crypto and settle in local currency; it powers
spend.2settle.io and chat.2settle, with $583K+ processed YTD. Multi-chain (BTC/ETH/Tron), HD wallets (BIP32/39/44), deposit monitoring, fraud detection, and fiat settlement. API + docs at api.2settle.io.