Shopify Functions development
Shopify Scripts stopped running on June 30, 2026. Logic that lived there has to be rebuilt.
In short
Lintel builds Shopify Functions: custom discount, delivery, payment and checkout validation logic that runs inside Shopify’s own infrastructure. Since Shopify Scripts stopped executing on June 30, 2026, Functions are where that kind of checkout logic lives.
What we build
- Discount Functions for rules the built-in discounts can’t express, on cart lines, the order subtotal or shipping.
- Delivery customizations that rename, sort or hide delivery options based on the cart.
- Payment customizations that rename, reorder or hide payment methods, and set payment terms on Shopify Plus stores.
- Cart and Checkout Validation that blocks orders breaking a rule, such as a quantity limit or a B2B minimum. See how validation works.
- Cart Transform functions for bundles.
- Scripts rebuilds: line item, shipping and payment Scripts rewritten as Functions. See where each Script’s logic goes.
The plan question comes first
Stores on any Shopify plan can use App Store apps that contain Functions, but only Shopify Plus stores can use a custom app that contains Functions. Some capabilities also need Plus whichever app you use, such as payment terms, and Cart Transform’s lineUpdate operation (also available on development stores). We check this in the first review, so the build takes the route your plan allows.
How Functions are built
- A Function receives only the data its GraphQL input query asks for, and it can’t read the clock or generate random values. Thresholds and settings usually live in metafields, so they can change without a code change.
- Functions run inside checkout with fixed resource limits, including a 256 kB compiled binary. Shopify recommends Rust for performance; JavaScript and TypeScript are also supported.
- Each Function is tested on a development store with realistic carts before it goes to the live store.
What to send us
Your store URL, your Shopify plan, and each rule in plain words: which carts it applies to and what should happen. If the rules used to run as Scripts, the Scripts customizations report in your Shopify admin lists them.
How an enquiry works
- Send a short briefTell us about the store and what isn’t working.
- We review itUsually within 24 hours.
- Scope and pricingWe discuss what the work involves and what it costs.
- Go ahead if there’s a fitThe project starts once scope and price are agreed.
Gencer KarakayaFounder & Shopify Engineer
Every brief is reviewed by the founder.
Questions
- Do I need Shopify Plus for Shopify Functions?
- Not for App Store apps: stores on any plan can use public apps that contain Functions. A custom app that contains Functions runs only on Shopify Plus stores, and some capabilities, such as payment terms, need Plus in any case.
- Can Shopify Scripts still run?
- No. Editing and publishing stopped on April 15, 2026, and all Scripts stopped executing on June 30, 2026.
- Can a Function call an external API?
- Only in limited cases: network access is available for some Function APIs, primarily on Shopify for enterprises, and Shopify has to enable it. Most rules are built on data already in Shopify, such as metafields.