> ## Documentation Index > Fetch the complete documentation index at: https://docs.mercurjs.com/llms.txt > Use this file to discover all available pages before exploring further. # Why Mercur > Why teams choose Mercur to run an enterprise marketplace: governance, ownership, and composability without a closed platform. The enterprise marketplace platform for teams that need governance, ownership, and control, not a closed SaaS. Mercur runs a multi-vendor marketplace on infrastructure you own. It gives an operator the governance a marketplace needs (role-based access, an auditable change pipeline, and per-seller settlement) while staying composable, API-first, and AI-native. You get the control of an enterprise platform without the closed code or a commission on gross merchandise value. ## Governance, built in A marketplace operator has to control who sells, what they change, and how money moves. Mercur builds that into the platform instead of bolting it on. * **Role-based access control:** members belong to stores with roles resolved per store, and every vendor request is scoped to its own seller. Access to one store never leaks into another. * **Auditable change pipeline:** every catalog edit is an immutable, attributed change with an approval queue, so you always know who changed what and who approved it. * **Per-seller settlement:** policy-based commissions, order splitting, and provider-driven payouts settle each seller independently and to the cent. ## You own the platform * **Own the code:** blocks ship as source you copy into your project. There are no black-box dependencies, and you can modify any line. * **Own the deployment:** self-host on your own cloud, on-premise, or a private network, with no hosted vendor in the request path. * **No lock-in:** Mercur is MIT-licensed, with no transaction fees and no commission on gross merchandise value. ## Composable, not monolithic Closed platforms give you a fixed feature set behind a console. Mercur gives you primitives. * Install only the modules, workflows, and UI extensions you need. * Extend core flows through hooks and the typed client, not by patching source. * Replace any layer, such as search, notifications, or payouts, with your own. Composable is not a step down from enterprise. It is how you make the platform fit your business instead of the other way around. ## AI-native, enterprise-governed Mercur is built so AI agents extend your marketplace within guardrails. Typed contracts, build gates, and version-matched docs mean an agent's change is correct by construction or it fails to compile. Agents work inside the same roles and review pipeline as people. They extend the platform, they do not bypass its governance. ## A proven commerce core Mercur does not reinvent commerce. Products, pricing, carts, orders, and payments run on the proven Medusa engine, so that layer is mature, maintained infrastructure from day one. On top of it, Mercur delivers the full marketplace platform: governance, multi-vendor orders, commissions, and payouts that a single-store engine does not provide. ## Mercur vs closed marketplace platforms Closed platforms such as Mirakl, VTEX, or Spryker deliver marketplace governance, but behind proprietary code, a fixed runtime, and a commission on your GMV. Mercur gives you the same operator governance with the opposite trade-offs. | | Closed platform | Mercur | | ------------- | ---------------------- | ---------------------------------- | | Code | Proprietary and opaque | Open source, you own it | | Hosting | Vendor-hosted | Self-hosted on your infrastructure | | Extensibility | Configuration only | Composable modules and workflows | | AI | Not agent-native | AI-native and governed | | Pricing | Commission on GMV | No GMV fees, MIT-licensed | ## Who it's for Mercur fits teams that need to run a real multi-vendor marketplace with operator governance, but want to own the code and the infrastructure rather than rent a closed platform. ## Next steps Set up Mercur and run a marketplace locally. How the marketplace platform is architected, module by module. Every marketplace capability, with its data models and workflows. Bundled docs, agent skills, and the MCP server.