Your website sells an item just handed over at the counter
Fictional example: one blue backpack remains. You sell it in the shop, but the website still shows one available and accepts another order. Someone now has to call the customer, offer a replacement or refund them. Start by identifying where stock is stored, when it decreases and how long each channel takes to receive a change.
Check whether your point-of-sale system and online shop already offer a suitable connection. Custom integration makes sense when that connection is missing or cannot cover an essential process. A new application is not automatically necessary.
An item on the shelf may not be available to sell
Separate physical stock from sellable stock. Items reserved for collection or damaged should not appear available. Shopify documents available, committed, unavailable and incoming inventory separately. Other systems may use different names: agree what each status means for your shop.
Check each product code and variant. A medium blue shirt is different from a large blue shirt. If online and till codes differ, establish a reviewed mapping first. Similar product names are insufficient grounds for changing quantities.
Choose the source of truth and reservation rules
Choose which system maintains the reference quantity and which report sales, reservations, cancellations and returns. Two applications should not overwrite the same quantity without conflict rules. Keep an operation identifier so that a repeated notification does not deduct stock twice.
Define when a reservation starts: a shopping basket, confirmed order and paid order are different events. Also agree expiry and who may release a reservation. Returned goods may require inspection before becoming sellable again.
Make connection failures visible
Periodic updates leave a window in which both channels may offer the same unit. Faster synchronisation reduces that window but does not by itself prove that overselling is impossible. For scarce products, assess central reservations, separate channel allocations or a safety buffer, depending on your systems' capabilities.
Pending operations and errors should be visible. Recovery must retry changes without duplication and reconcile quantities afterwards. If the till operates offline, explicitly agree what can still be sold and what happens on reconnection.
Checks to agree before accepting delivery
These are proposed integration checks, not results from an Adaris customer deployment.
- Two purchases compete for the last unit and the agreed rule is respected.
- A duplicate notification deducts only one sale.
- Cancellation releases the correct reservation without adding extra units.
- A damaged return does not become sellable stock.
- A connection failure leaves pending changes visible to staff.
- Changes to one variant or warehouse do not affect another.
Start with two channels and a small catalogue
A first project can connect one till system and one online shop for a product family. Agree mappings, reservations, error records, reconciliation and acceptance checks. Full catalogue migration, additional warehouses, invoicing and customer messaging require separate scoping.
To assess the work, provide your software names, sales channels and an example stock discrepancy. Adaris works from Elche with shops in Alicante and across Spain, with commercial communication in Spanish. A quote separates development, any connector licences, hosting and maintenance. This is a service scope to assess, not a ready-made connector for every till.
Related services
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Where does your stock fall out of sync?
Tell us which till and online shop you use, with a fictional example of a problem sale. We can assess a first integration. Do not send credentials or customer lists. Commercial communication is in Spanish.