Demo Store with Commerce.js and Next.js is an open-source reference storefront built using Next.js and the Commerce.js API to demonstrate how to implement a modern headless eCommerce experience using the JAMstack architecture. The project provides a fully functional online store that includes essential commerce features such as product listings, categories, shopping cart functionality, checkout flows, and customer account management. It is designed to showcase how developers can integrate a serverless backend with a frontend framework, enabling fast, scalable, and highly customizable eCommerce applications. The demo store leverages Commerce.js APIs to manage carts, checkout processes, customer authentication, and order handling without requiring a traditional monolithic backend. It also supports integrations with payment providers such as Stripe and includes preconfigured workflows for applying discounts, selecting shipping methods, and handling regional configurations.