OpenCart - A free shopping cart system. OpenCart is an open source PHP-based online e-commerce solution.s
Sendlane - Marketing automation and campaign management solution
PrestaShop - Create your online store with PrestaShop's free shopping cart software. Build an ecommerce website for free and start selling online with hundreds of powerful features.
CS-Cart Multi-Vendor - On-premises eCommerce marketplace builder
WooCommerce - A freely available eCommerce plugin that enables shop facilities on your WordPress website. Functionality enabling extensions & beautiful themes available.
SmartEngage - Cross-channel autoresponder for marketing automation