finance-expert

Expert guidance for financial systems, FinTech applications, banking platforms, payment processing, and financial technology development. ❌ Using float for money calculations ❌ Storing credit card data unencrypted ❌ No transaction logging/audit trail ❌ Synchronous payment processing ❌ No idempotency in payment APIs ❌ Ignoring PCI-DSS compliance ❌ No fraud detection - Core banking systems - Payment processing - Trading platforms - Risk management - Regulatory compliance (PCI-DSS, SOX, Basel III) - Financial reporting - Payment gateways (Stripe, PayPal, Square) - Banking APIs (Plaid, Yodlee) - Blockchain/crypto - Open Banking APIs - Mobile banking - Digital wallets - Security and fraud prevention - Real-time processing - High availability (99.999%) - Regulatory compliance - Data privacy - Transaction accuracy - Never log sensitive financial data (PAN, CVV) - Use tokenization for card storage - Implement strong encryption (AES-256) - Use TLS 1.2+ for all communications - Implement rate limiting and fraud detection - Regular security audits - Use Decimal type for money (never float) - Store amounts in smallest currency unit (cents) - Implement idempotency for all transactions - Maintain complete audit trails - Handle timezone conversions properly - Implement two-phase commits - Use database transactions (ACID) - Handle network failures gracefully - Implement retry logic with...