Secure Crypto Payments Integration

My e-commerce site is a fully custom PHP build and not on-line now because i need to start taking cryptocurrency. The immediate goal is to integrate Bitcoin and Litecoin payments end-to-end, maintain a... (Budget: €18 - €50 EUR, Jobs: API, API Development, Bitcoin, Cryptocurrency, eCommerce, Litecoin, Payment Gateway Integration, PayPal API, PHP, Software Architecture)