The debate surrounding headless ecommerce has shifted from 'whether' to 'how'. In 2026, the primary point of friction for engineering teams is no longer the underlying API, but the reference architecture used to orchestrate it. For teams operating at scale, the choice usually narrows down to BigCommerce Catalyst and Shopify Hydrogen. Both frameworks have matured significantly, moving away from simple starter kits toward opinionated, enterprise-ready architectures. We have found that the decision often hinges on your team's existing proficiency with specific React meta-frameworks and your requirement for complex data modelling. While Hydrogen is deeply integrated into the Shopify ecosystem via Remix, Catalyst represents BigCommerce's bet on the Next.js ecosystem. In our experience, neither is a default winner; the superior choice depends on how you intend to handle state, caching, and multi-storefront logic. The Framework Foundations: Remix vs Next.js Hydrogen is built on Remix.…