Keep a Handmade Product's Shopify Stock in Sync with Its Materials

A workshop makes tote bags from a shared roll of canvas. Its team knows the available canvas in Soply, but the Shopify sales variant still shows an older, manually entered stock number. The store wants that variant's native Shopify inventory to reflect the quantity supported by its materials.

Illustrative scenario: Stock quantities and preview targets below are examples, not a real merchant's results.

Separate the calculation from the write

Suppose 15 meters of canvas are available to use, and one tote bag requires 2 meters. Canvas supports floor(15 ÷ 2) = 7 complete bags. If Shopify currently shows 10 bags at the one fulfillment location, the two systems disagree. The example's material-based target is 7, assuming no other binding, order, or location limit.

Soply can calculate this result without changing Shopify inventory. Writing it to the tote-bag variant requires the separate Product stock sync setting. A preview lets staff inspect the affected variant, location, current quantity, and proposed target before saving.

Set up and check the target

1. In Raw Materials, create or open the canvas material and confirm its Available to use quantity.
2. In Product Usage, bind the correct tote-bag Shopify variant with 2 meters as Consumption Per Unit. Check that its calculated availability is the expected 7 in this simple example.
3. Under the material's Inventory settings → Product stock sync, review automatic updates for products using this material. With one fulfillment location, check that the intended target is that location. With several locations, review how Distribute total allocates the combined calculated quantity.
4. On a saved material, use Preview changes. Confirm that the tote-bag variant, location, current Shopify stock, and proposed target match your plan. Previewing does not change inventory.
5. Save the sync setting only after the preview is correct, then check the actual Shopify inventory and test a reasonable cart quantity.

Avoid conflicting stock writers

This scenario concerns the bound sales product, not the Shopify variant that might serve as a material's stock source. They have separate sync settings. If another app, ERP, or warehouse system also writes the tote-bag SKU, decide which system owns its quantity before turning on Soply writeback. For variants that share a material pool, individual Shopify quantities are not independent pools; verify purchase validation as well.

Shared pool mirror is for eligible pickup locations sharing one physical pool and can make the displayed sum across locations misleading. Use it only when that fulfillment arrangement is real and its prerequisites are met. See When Soply updates Shopify inventory, How material availability is calculated, and Cart and checkout validation.