Medusa.js
The world's most flexible commerce platform
...It's designed for developers to build custom, scalable e‑commerce applications such as B2B, DTC stores, marketplaces, point-of-sale systems, and service businesses without reinventing core functionality. Medusa is a commerce platform with a built-in framework for customization that allows you to build custom commerce applications without reinventing core commerce logic. The framework and modules can be used to support advanced B2B or DTC commerce stores, marketplaces, distributor platforms, PoS systems, service businesses, or similar solutions that need foundational commerce primitives. All commerce modules are open-source and freely available on npm.