Guardrail protects the products you don't want discounted — across every code, no matter which app or campaign created it. Klaviyo, loyalty, influencer tools, Flow, all of it.
Built on Shopify Functions · Replaces Shopify Scripts (June 30, 2026)
Sitewide sales. Influencer codes. Klaviyo pop-ups. VIP tiers. Flow automations. Every one of these can apply a code to products that should never be discounted — your clearance, your MAP-protected brands, your gifts-with-purchase, your wholesale-only SKUs.
And then Shopify Scripts shuts down June 30, 2026.
Set rules per product, vendor, or tag. Mix and match across your store.
The discount applies to everything else in the cart, but your protected items stay at full price. Clearance, MAP items, gifts-with-purchase — untouched.
When a protected product is in the cart, the discount doesn't apply at all. Your shopper sees a clear message explaining why.
Allow some discount, but limit it. Cap by dollar amount or percent on items where bigger discounts hurt your margin or break vendor agreements.
Tags. Vendors. Collections. Compare-at-price. Even profit margin. If it's in your store already, you can build a rule with it.
Klaviyo doesn't know your MAP agreements. Loyalty apps don't know your clearance margins. Influencer tools don't see vendor restrictions. Guardrail handles it at checkout — where every discount actually applies — so it doesn't matter which app the code came from.
Shopify Scripts is shutting down June 30, 2026. If your team uses Scripts to block discounts on certain products or carts, Guardrail does the same thing — without you having to update every app that creates discount codes.
We've built templates for the most common Scripts setups, so you're not starting from scratch.
Guardrail uses Shopify Functions — the same checkout extension system Shopify itself uses for discounts. Rules apply during checkout, not after. No theme code. No webhook delays. No edge cases where a discount slips through before you can stop it.
From your sitewide sale, your influencer campaign, your loyalty program — wherever the code came from.
In milliseconds, Guardrail checks the cart against your rules. Right inside checkout, before the discount lands.
The right items get discounted. Protected items stay at full price. Your shopper sees a clear message if anything's blocked.
No theme code. No workarounds. Just Shopify.
Every protected discount is logged: which rule triggered, which product was protected, and how much margin you kept. Show your finance team the exact dollars Guardrail saved this month.
Priced by monthly orders. Block-the-cart mode included on every plan. Scripts migration help included on Plus.
No. Guardrail uses Shopify Functions, the same checkout extension Shopify recommends for all modern discount apps. It reads what's already in your catalog — tags, vendors, collections, prices — and applies your rules no matter which app created the code.
Shopify's built-in exclusions only work on discounts you create in Shopify Admin. They don't cover codes from Klaviyo, loyalty apps, or influencer tools. Guardrail applies one set of rules across every code, no matter where it came from.
Shopify Scripts stops working on June 30, 2026. Whatever rules your team built with Scripts — blocking discounts on certain SKUs, rejecting entire carts — Guardrail can do the same. We have templates for the most common Scripts setups to get you moved over fast.
No. Shopify Functions are designed to run instantly inside checkout, and Guardrail pre-calculates everything it needs (like margin values) ahead of time. Your customers won't notice it's there.
Yes. Tags, vendors, collections, metafields, and compare-at-price are all available as rule inputs. Most stores start by using tags they already have in place.
Most Guardrail features work on any Shopify plan, but the Block-the-cart mode is only available on Shopify Plus due to Shopify's platform rules.
Install Guardrail and protect your products from accidental discounts.