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The Back-in-Stock module captures customer WhatsApp numbers when a product variant is out of stock and automatically sends a notification when inventory is replenished. The widget is injected directly into your Shopify storefront — no manual theme editing is required. This guide walks you through customizing the widget, verifying it on your storefront, submitting a test subscription, and confirming the restock notification fires correctly.

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What this covers

  • Customizing the widget appearance
  • Verifying the widget appears on out-of-stock product pages
  • Submitting a test subscription
  • Triggering a test restock notification

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Before you begin

Your WhatsApp Business Account must be connected before restock notifications can be sent. The widget itself can be installed and tested for subscription capture independently, but notifications require an active WhatsApp connection.

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Setting up the widget

1

Open Back-in-Stock settings

In the Galantis dashboard, go to Back-in-Stock → Settings.
2

Customize the widget appearance

Configure the widget to match your brand. Key settings include button position (right, left, or custom), button background color, CTA label text, headline text shown in the subscription modal, and form background colors.
3

Verify the widget on your storefront

Visit a product page on your Shopify store where at least one variant is out of stock. The subscription button should appear automatically. If it does not appear, confirm Galantis has write_script_tags permission in Shopify and clear your browser cache.
4

Submit a test subscription

Enter your own WhatsApp number in the widget form and submit. A subscription record will be created in Galantis with ACTIVE status.

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Testing the restock notification

1

Locate the subscribed variant in Shopify

In your Shopify admin, find the product and variant you subscribed to in the previous step.
2

Update inventory to a positive quantity

Change the variant’s inventory from 0 to any positive number and save. This triggers a products/update webhook from Shopify.
3

Confirm the notification is sent

Galantis detects the inventory change, fires the BACK_IN_STOCK automation trigger, and sends a WhatsApp notification to all ACTIVE subscribers for that variant. Check your WhatsApp — you should receive the restock message within a few seconds.
4

Check subscription status

In Back-in-Stock → Subscriptions, confirm the test subscription moved from ACTIVE to NOTIFIED. Notified subscriptions do not receive a second notification for the same restock event.

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Subscription status reference

Only customers with SUBSCRIBED or better marketing consent status receive restock notifications. Customers with UNSUBSCRIBED or REDACTED status are automatically excluded, even if they have an ACTIVE subscription record.
  • Back-in-Stock — Full module reference including widget design options, inventory rules, and analytics
  • WhatsApp Connection — Required for sending restock notifications