Add a marketplace to your Shopify store
Open your eCommerce to third-party vendors, while Shopify stays your core commerce engine. No migration, no replatforming, no vendor lock-in.
How Shopify and Mercur work together
Shopify stays your commerce core – storefront, checkout, payments, taxes. Mercur runs the third-party marketplace beside it, connected over APIs and events. Each scales on its own.
You bring your own vendors – the suppliers and partners you already work with. No network to rent, no marketplace to share.
Why keep marketplace logic out of your Shopify core?
| Marketplace as a Shopify app | Marketplace on Mercur, beside Shopify |
|---|---|
| Vendors squeezed into users or staff | A real per-vendor system of record |
| Logic scattered across apps | Isolated, with its own extension points |
| Bound by the app model's limits | A full engine – BuyBox, settlement, command center |
| You outgrow it and replatform | Vendors scale without a rebuild |
What changes in your store once you add a marketplace?
With Mercur, product pages show competing offers, one checkout covers every vendor, and one customer order becomes a separate order, payment, and payout per vendor.
Onboard a vendor
A configurable application, KYC and KYB through your payment provider, and a hard rule: no verification, no payout.
List the catalog
Bulk import by file or API with a mapping wizard. Listings dedupe by EAN, so three versions of one phone become one product with competing offers.
Win the sale
Offers compete on price and availability. The BuyBox picks the winner and shows every vendor standing behind it.
Take a mixed cart
One checkout across your own products and third-party offers, with shipping costed per vendor.
Split the order
The cart breaks into a separate order and payment per vendor, on its own.
Fulfill and track
Logistics classes, lead times, lockers, and multi-shipment – with a status flow where only the admin marks an order received.
Settle and pay out
An append-only ledger, real Pending, Payable, and Paid balances with a Reserved bucket for holds, statements, and invoices. The balance a vendor sees is the money they get.
Handle returns and disputes
Per-line returns on your policy window, refunds that match the books, and disputes that hold a payout until they close.
Discover how to add a Shopify marketplace to your store
Tell us about your eCommerce and what you want to sell third-party. Our experts will show you how it connects to your stack, how long it takes, and what it costs.
How Mercur compares with SaaS marketplace platforms
| SaaS Marketplace | Mercur | |
|---|---|---|
| Core technology | Closed, vendor-only | Open source (MIT), public |
| Enterprise code | Black box | Full source for licensees |
| Integrations | Separate products | Built into one platform |
| Customization | Tickets and workarounds | Your own layer, official extension points |
| Deployment | Vendor cloud only | Any cloud or on-premise |
| Cost model | A percentage of your GMV | Zero GMV fees |
| Exit | Lock-in | You keep what you paid for |
| Developer pool | Certified specialists | Any web developer |
How the connector communicates with Shopify
Mercur connects to Shopify over OAuth and the Admin API. Your Shopify catalog, prices, and stock flow into Mercur as offers; Shopify stays the storefront and checkout your customers already use.
What the connector does in your Shopify store
Onboards a Shopify store over OAuth, with encrypted credentials.
Syncs products, prices, and inventory inbound, with AI-assisted mapping.
Signed webhooks keep Mercur current as your catalog changes.
Connect is the integration framework, and the Shopify connector is a working pattern in it. Production-grade delivery and your exact setup – including headless – we configure per deployment. Connect is part of Mercur Enterprise.
What the integration process looks like
The team that builds Mercur can take you through all four steps.
Marketplaces built on Mercur
Montelink
B2B2C online consultation marketplace for independent advisors and business experts, with a per-minute billing engine and custom expert panel.
Material Index
Material Index lets contractors, architects and developers buy and sell reclaimed materials, live in the UK and licensed in Australia, the USA, and Spain.
Suplement.io
Suplement.io equips supplement brands with EU-based manufacturing – ready-to-brand products, private-label formulation and compliance – in 20+ EU countries.
FAQ on adding a marketplace to Shopify
See how leading brands build their marketplace
Talk to the team behind Mercur – how it works, how other brands build with it, and where it fits for you.