We built Stackable because discounts kept breaking at the one moment that matters
Not in the cart preview. Not in the admin dashboard. At checkout, on the order a customer actually pays for.
Look through enough reviews of discount apps and a pattern shows up again and again: a price looks right in the cart, then something different gets charged at checkout. A customer pays full price for something a merchant promised at a discount, or two discounts that should have stacked silently don't, and nobody notices until a refund request lands in support.
The pattern gets worse at the exact moments merchants care about most. Around Black Friday and Cyber Monday, when traffic spikes and every order counts, is exactly when these bugs are most likely to surface, because that's when carts are fullest and discount rules are stacked hardest. And accelerated checkouts - Shop Pay, Apple Pay, Google Pay, PayPal - run their own code path, so a discount that works perfectly in a normal checkout can quietly vanish in a one-tap payment flow that a merchant never personally tests.
There's a second failure mode that's just as damaging to trust: apps that change a product's actual price to show a discount, and leave it changed after the merchant uninstalls. A clean uninstall should mean the store looks exactly like it did before the app was ever added. That shouldn't be a bonus feature - it should be table stakes.
Stackable is built around one idea: a discount app's only job is to be right, everywhere, every time. Not right in the cart and hopeful at checkout. Right in the cart, right at checkout, and right in every accelerated payment flow - because Shopify computes all of them from the same server-side rule, if you build the app that way.
What "Stackable" is supposed to mean
Specific commitments, not a marketing slogan. This is what "Stackable" is supposed to mean.
One rule, computed server-side, everywhere
Every discount is computed by a Shopify Function running on Shopify's own servers - the same function evaluates the cart, the checkout, and every accelerated checkout. There is no separate client-side estimate that can drift from what the customer is actually charged.
We never touch your product prices
Stackable applies discounts as overlays at checkout - it never mutates a product's compare-at or actual price in your catalog. Uninstall the app and your store's prices are exactly what they were before you installed it. No cleanup script, no leftover price changes.
Pause takes effect in under 60 seconds
When you pause a live campaign, it stops applying at checkout in under 60 seconds. If something looks wrong, you can shut it off and trust that it's actually off - fast, not "eventually" off.
Storefront widgets are SEO-safe
Tier tables, sale badges, and progress bars render without injecting extra H1 or heading tags into your theme's document outline, so a merchandising widget never quietly hurts a page's SEO structure.
We will never pressure you for a review
No review-gating popups, no discount held hostage behind a 5-star ask. If Stackable earns a good review, it's because the discounts worked - not because we asked at the right moment.
The team
The team building Stackable, the reliability-first bulk and volume discount app for Shopify. We write about discount stacking, Shopify Functions, and how to run promotions that hold up at checkout.
Builder of Stackable. Focused on making Shopify discounts reliable end to end, from cart to checkout to accelerated checkout.
See it hold up in your own cart
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