Catch the buyers
you’d lose to
sold out.

When a variant runs out, BackBy swaps “Add to cart” for Notify me when it’s back. Shoppers drop their email, and BackBy emails them the moment it’s back — automatically, on every plan.

Auto-flip on zero stock

The capture button appears the second inventory hits zero — no per-product toggling, no missed sell-outs.

The list is yours

Export the waitlist as CSV or sync to Klaviyo and Shopify Email. Your recovered demand, in your tools.

The alert sends itself

When stock returns, every waiting shopper is emailed for you — and only marked notified once the email has actually sent.

Catch the buyersyou’d lose tosold out.

Auto-flip on zero stock

The list is yours

The alert sends itself

Catch the buyers
you’d lose to
sold out.