Shopify Functions, without the code or the invoice

Build Shopify Functions as rules. Free on live stores.

SMART Functions Creator turns discounts, payment and delivery customizations, checkout validations, and cart transforms into rules you can read. It is the replacement for Shopify Scripts that works on every plan and does not charge per rule.

Five Function types · every Shopify plan · no subscription

★★★★★ 5.0 stars · 110+ reviews

Start with the question you have

The things merchants ask us most, answered in full.

Shopify Scripts ended on 2026-06-30

Line item, shipping, and payment scripts each have a Functions equivalent. We help you rebuild them.

There is no paste-your-Ruby button, on this app or any other, because Shopify does not let public apps run merchant code. What there is: a rule builder that covers what scripts did, templates for the common ones, and fast support in the app chat for the rules that are not obvious.

Line item scripts

Discount rules with Line groups, tiers, BXGY, and bundles

Shipping scripts

Delivery customizations for visibility, shipping discounts for price

Payment scripts

Payment customizations matched on the internal method name

Read the migration guide →

Discount Functions

Tiers, gifts, bundles, and wholesale pricing as rules, not Ruby.

  • Product, order, volume, and shipping discounts, automatic or with a code
  • Percentage off, fixed amount off per unit, or a fixed price per unit
  • Templates for BOGO, buy X get Y, bundles, and quantity tiers
  • Line groups by product, collection, tag, SKU, variant name, metafield, or line item property

Every line item script we have seen maps onto one or two discount rules. Quantity tiers reprice all units once a threshold is reached, gifts are 100 percent discounts on a gift group, and combinations are set explicitly on every rule so you know what stacks before a customer does.

Volume discountLive

Wholesale tiers: sharpening stones

Applies to
Collection: Stones
Customer
tag is wholesale
Tiers
5+ at 3.90 per unit, 50+ at 3.56 per unit
Group by
All products

Checkout shows: 50 x Stone 1000: 178.00 (was 235.00)

Payment and delivery customizations

Hide, move, and rename methods by condition.

  • Hide Cash on Delivery above an amount or for tagged customers
  • Hide Express shipping when fragile or oversized products are in the cart
  • Rename methods for B2B customers or per country
  • Conditions on cart total, products, tags, country, postal code, weight, and subscription presence

These replace shipping and payment scripts. Rules match Shopify's internal method names, the docs show how to find them, and the one platform limit that matters (the main credit card option on US and Canadian non-Plus stores) is stated up front rather than discovered at checkout.

Payment customizationLive

Hide COD above 200

Method
name contains "Cash on Delivery"
Condition
Cart total is greater than 200
Action
Hide

Checkout shows: Cash on Delivery not listed for a 240.00 cart

Validation and cart transform

Stop the checkouts that should not happen, and shape the ones that should.

  • Minimum quantities, quantity multiples, and per-product caps
  • Block mixed carts, PO box addresses, or products a customer is not tagged for
  • Your own error message, shown in the cart or at checkout
  • Merge bundle lines or expand a kit into components with cart transform

Scripts could never stop a checkout. Validations can, with a message you write. Cart transform merges or expands lines so bundles look like bundles. Both run on every plan; Shopify keeps line updates for Plus and development stores.

Cart and checkout validationLive

Cases of 12 only

Line group
Collection: Wholesale beverages
Condition
Quantity is not a multiple of 12
Message
Order beverages in cases of 12.
Runs on
Checkout interaction, completion

Checkout shows: Checkout blocked at 30 units until 24 or 36

Honest limits

What Shopify Functions cannot do, on any app.

No gift auto-add

A Function can make a gift free, not put it in the cart. The customer or your theme adds it.

No code rejection

Shopify accepts a valid code before the Function runs. The Function withholds the amount; it cannot show a custom message.

Combination rules are Shopify's

Both discounts must allow each other, and one product gets one product discount. Every builder lives inside this.

The full list is on what the app does not do.

Merchant reviews

Real merchants, real words.

SMART Functions Creator holds 5.0 stars across 110+ reviews on the Shopify App Store listing.

★★★★★
Very impressed with both the functionality to create a discount with conditions I couldn't replicate with Shopify's native functionality, and the prompt and helpful support from the team when I needed assistance.
Shopify App Store review
★★★★★
While the app does have certain limitations, their top-notch support more than makes up for it. App developers go above and beyond to provide alternative solutions for custom functions. Since the deprecation of Shopify Scripts, this app has been extremely useful with building out custom rules for our Plus store. Highly recommend!
Shopify App Store review

At a glance

The numbers merchants check.

5.0 stars

across 110+ public reviews on the Shopify App Store

5 Function types

discount, payment, delivery, validation, cart transform

Every plan

Basic through Plus, one feature set, no Plus requirement for the core

$0

on live stores, no subscription, no rule cap from the app

Ready to rebuild the logic your checkout is missing?

Install on Shopify, start from a template, and ask chat if a rule is not obvious. Free on live stores.

Install free on Shopify

On the Shopify App Store · uninstall anytime