Lean Epay payment gateway

I need a complete payment gateway that can process Credit/Debit cards, Cryptocurrency, and Bank transfers seamlessly across Web, Mobile, and in-store POS environments. Robust security is non-negotiable, so the build must include Two-factor authentication, end-to-end Encryption, and smart Fraud detection baked into every transaction flow.

To keep the scope crystal-clear, here’s what I must walk away with:
• A scalable back-end capable of handling the three payment methods above
• Front-end or SDK components that drop into web apps, native mobile apps, and common POS terminals
• Security layer implementing the three features named earlier, with compliance reporting enabled
• Clean API documentation and a minimal admin dashboard so I can track transactions and manage keys

I’ll consider the project complete once test transactions for each payment type run flawlessly on all three platforms, security audits pass, and the documentation lets another developer integrate within a few hours.