Reaction Commerce is an open source reactive and microservices oriented platform. It is written in ES6 with the Meteor framework and Node.js. MongoDB is the database to store application data. The Reaction platform uses Hydra as a OAuth2 server for authorising access to the API.
The storefront is built with Next.js and React which communicates with the backend via GraphQL. Rendering is server-side. It has basic eCommerce features out of the box, such as product catalog, search, one step checkout and customer account.
Thanks to the microservice architecture, the platform is flexible and can be extended and connected with a number of external services, such as PIM, ERP, CMS.
The project is developed and managed by the Reaction Commerce company and is funded by a number of VCs, including Female Founders Fund. Hence it is open source, everybody can contribute.
The documentation is quite comprehensive with multiple tutorial videos. However, some of them are outdated and valid to 1.x version only. The project has a scalable architecture and is definitely a high-potential one. But in our opinion it is not stable enough yet to use in complex systems.