Inventory Management
Keep track of stock across warehouses, stores, vendors, and channels with a headless inventory engine built on Medusa and extended for marketplaces in Mercur. Mercur’s Inventory module is where you define inventory items, connect them to product variants, and control where and how they are available. It gives you a single, real-time view of stock across all locations - whether it’s your own warehouse or a vendor-managed drop-ship location.
How you manage inventory in Mercur
Give your operations team and vendors a consistent way to manage stock without tying them to a specific storefront or WMS.
With the Inventory module, you can:
- Create and manage inventory items linked to product variants in Mercur.
- Define stock locations such as central warehouses, retail stores, vendor warehouses, and 3PL partners.
- Set and update inventory levels per item and per location directly in the admin panel or via API.
- Decide where items are sellable by mapping locations to sales channels and markets.
- Use reservations during checkout and order flows to prevent overselling on high-traffic channels.
- Configure backorders, pre-orders, and stock rules based on your business logic.
- Let marketplace vendors manage their own stock while you keep a consolidated, operator-level view.
Build custom marketplace with Mercur
Create your unique multi-vendor platform with our powerful, flexible marketplace solution that adapts to your business needs.
What the Inventory module delivers for your business
Real-time stock visibility
See accurate stock numbers across all locations and channels in one place. No more spreadsheets or conflicting reports from different systems.
Multi-location, multi-channel ready
Support central warehouses, local stores, vendor locations, and drop-shippers in a single model. Decide which stock powers which storefront or region.
Reduced overselling & stock errors
Reservations and precise inventory levels per location help you avoid overselling and customer disappointment, especially during peaks and campaigns.
Marketplace-grade flexibility
Assign inventory to individual vendors, share products across sellers, and keep a global view of availability — ideal for B2B2C and multi-vendor setups.
Developer-friendly, API-first
The underlying Medusa inventory model is fully exposed via APIs. This makes it easy to integrate ERP, WMS, 3PLs, or custom tools without hacks.
Medusa-compatibility
Everything compatible with Medusa platform
Core capabilities
1. Inventory data model
A dedicated domain for inventory that cleanly separates stock from product data:
- Inventory items represent stock-keeping units connected to product variants.
- Store base attributes such as SKU, dimensions, and weight.
- Use metadata to add custom attributes like batch number, expiry date, owner (vendor), or internal tags.
- Manage items centrally in Mercur Admin or programmatically via API.
2. Stock locations
Model where your inventory physically lives:
- Create and manage stock locations – from central warehouses to retail stores and vendor warehouses.
- Set location attributes such as address, type (warehouse, store, vendor, 3PL), and priority.
- Assign locations to sales channels to control which stock is exposed to which storefront or market.
- Use locations as routing points for fulfillment and shipping flows.
3. Inventory levels & adjustments
Control how much stock is available at each place:
- Track inventory levels for every inventory item at every location.
- See at a glance what is available, reserved, and sold.
- Update levels manually from the admin or automatically via integrations with ERP/WMS.
- Support stock adjustments for returns, damaged goods, and internal moves.
4. Reservations & allocations
Avoid overselling without locking your system:
- Create reservations when customers add items to cart or place an order.
- Reservations temporarily hold stock at a chosen location until the order is captured or cancelled.
- Manage reservations directly in the admin: view, edit, or delete them when operations require manual intervention.
5. Sales channel availability
Decide where each piece of stock can be sold:
- Map stock locations to sales channels such as different storefronts, regions, or B2B portals.
- Expose certain locations only to specific channels (e.g. vendor stock only on marketplace).
- Support different assortments per region without duplicating the entire catalog.
6. Backorders & stock rules
Sell beyond current stock when it makes sense:
- Configure whether items can be sold when stock reaches zero.
- Run pre-order campaigns with clear expectations around shipping dates and availability.
- Implement safety stock or low-stock thresholds using hooks and metadata.
7. Marketplace & multi-vendor inventory
Designed from day one for marketplace scenarios:
- Store separate inventory per vendor, even when multiple vendors sell the same product.
- Let vendors manage their own locations and stock levels.
- Use API-based updates so vendors and 3PLs can sync inventory from their own systems.
Build custom marketplace with Mercur
Schedule a guided tour of Mercur Marketplace tailored to your specific marketplace requirements. Connect with our team to discuss how we can help bring your marketplace vision to life.