Zen Cart - Zen Cart
AffiliateWP - A powerful affiliate marketing solution for WordPress.
OpenCart - A free shopping cart system. OpenCart is an open source PHP-based online e-commerce solution.s
ReferralMagic - Turn your users and customers into referral magnets.
PayKickstart - PayKickstart is the ultimate shopping cart and affiliate management platform, empowering online Entrepreneurs and digital publishers with the tools to sell their products online.
Echo - Golang HTTP server framework