Auto-hide sold-out products and republish on restock

01/The build

How to build it

1. 01

   Decide your hide rule, your two thresholds, and your exclusions

   Needs a human

   Pin down the policy before automating anything. What counts as 'out': every sellable variant at or below zero across the locations that actually fulfill online orders, and the variant's inventory policy set to 'deny' (not 'continue', which means you're overselling on purpose). Set two numbers, not one: hide at 0, republish only at a small buffer (say 3) so one stray unit doesn't relist a product. List what never auto-hides — made-to-order SKUs, preorders, continue-selling items, and anything you tag 'always-live'. And decide hide-vs-keep per collection: for a hero product with ranking and backlinks, you may prefer keeping the page up with a back-in-stock signup instead of hiding it.

2. 02

   Catch Shopify's inventory-level webhook in n8n

   Runs itself

   Subscribe to the inventory_levels/update webhook and point it at an n8n webhook node. The payload is lean — it carries inventory_item_id, location_id, and the new available quantity, not the product. That's fine; the next step resolves it. This single topic fires for both directions: a sale that drains stock and a restock that refills it, so one trigger drives both the hide and the republish.

3. 03

   Resolve the inventory item to its product and read every variant

   Runs itself

   The webhook only gives you an inventory_item_id, so look up what it belongs to. Use Shopify's GraphQL inventoryItem query to walk inventoryItem → variant → product, then pull the product's full variant list with each variant's inventoryPolicy and its available quantity per location (quantities(names: ["available"]) on each inventory level). You need the whole product's picture, not just the one variant that changed — hiding on a single sold-out size when other sizes are in stock is exactly the mistake to avoid.

4. 04

   Decide whether the product is genuinely out

   Runs itself

   Hide only when every sellable variant is at or below zero across the fulfilling locations and its inventory policy is 'deny'. Sum available across those locations per variant — and ignore a damages, quarantine, or staff location that never ships to customers, or you'll keep a product live on stock no online order can ever pull from. Then apply the exclusions from step one: skip continue-selling, preorder, made-to-order, and always-live products. If even one variant can still be bought, the product stays live.

5. 05

   Hide it and stamp it with a tag

   Runs itself

   Set the product's status to DRAFT with the productUpdate mutation (or, if you want it gone from the Online Store but kept on POS and other channels, unpublish just that publication instead). In the same run, add a tag like auto-hidden-oos plus the date. That tag does two jobs: it's the idempotency key so a re-fired webhook won't act twice, and it's the marker that this flow — not a human — hid the product, which is what makes a safe automatic republish possible.

6. 06

   Republish only what the flow hid, when stock crosses the buffer

   Runs itself

   When an inventory_levels/update for a restock comes in, resolve it to the product as before and check two things: does it carry the auto-hidden-oos tag, and is total sellable inventory now at or above your republish buffer from step one? Only if both are true do you set status back to ACTIVE (or re-publish the Online Store publication) and remove the tag. Gating on the tag is what keeps the flow from ever un-hiding a product a person deliberately set to draft.

7. 07

   Add hysteresis so the listing doesn't flap during a sale

   Runs itself

   Inventory near zero is noisy — a unit sells, a return restocks it, a count corrects — and a naive flow would hide and show the same product several times an hour. The gap between your two thresholds (hide at 0, republish at 3) already absorbs most of it. Add a short debounce on top: when a hide or republish would fire, wait a minute, re-read the product's current stock, and only act if it still qualifies. That turns a flurry of webhook events into one clean state change.

8. 08

   Reconcile on a schedule and flag the exceptions

   Runs itself

   Webhooks get dropped. Once a day, run an n8n schedule that pulls products carrying the auto-hidden-oos tag and confirms they're genuinely still out, and scans live products for any that are silently at zero. Fix the drift automatically where the rule is unambiguous, and post the genuine oddities — a product a human drafted that's now back in stock, a SKU whose locations don't add up — to wherever you watch ops, for a person to settle. The automation handles the rule; it never guesses on the edge cases.

02/The stack

What it’s built on

Shopify

System of record for both the inventory and the listing. It emits the inventory_levels/update webhook, answers the variant-and-location lookup, and is where you flip product status to draft or active and write the auto-hidden-oos tag.

n8n

The glue: receives the inventory webhook, resolves it to the product, runs the out-of-stock and restock decisions with their thresholds and debounce, makes the hide/republish call, and runs the daily reconcile.n8n is open-source and self-hostable for free; their cloud tier just saves you running it yourself. Zapier can do the simple version, but the per-variant, multi-location logic and the debounce are far cleaner in n8n's code and branching nodes.

03/Questions

Before you build