What is composable commerce?

Composable commerce is an architectural approach where each capability in an ecommerce stack — commerce engine, search, CMS, payment, CRM, PIM, OMS — comes from a separate specialist vendor and connects to the rest of the stack through APIs. The merchant assembles a working ecommerce system from best-of-breed services rather than buying one monolithic platform. Each capability is what Gartner calls a Packaged Business Capability (PBC). The pattern extends headless commerce, which decouples one boundary (the storefront from the commerce engine), by decoupling every layer of the stack from every other. A composable stack is always headless; a headless stack is not always composable. Most projects described as composable are not fully composable. They are headless stacks with two or three composable additions on top of an otherwise integrated platform — typically a dedicated search vendor and a dedicated CMS. Full-composable, with every layer independently swappable, is rare outside enterprise deployments. For the deep-dive covering when composable is the right choice, when it is not, and where most projects actually land in practice, see the composable commerce pillar post. ## Related terms Headless commerce · MACH architecture · Microservices commerce · API-first commerce