What is Shopify Functions?
Shopify Functions = serverless code (WASM) that runs inside Shopify's checkout. Lets you customize discounts, shipping methods, payment customizations, and cart validation server-side at scale.
The definition
Shopify Functions = serverless WebAssembly code that runs inside Shopify's checkout pipeline. Available on all plans (some advanced capabilities Plus-only). You write Rust or JavaScript, compile to WASM, deploy via the Shopify CLI.
What you can do with it
Custom discount logic that can't be expressed in Shopify's UI (e.g., 'BOGO but only for customers with LTV >$200'). Custom shipping logic ('free shipping if cart contains a subscription item'). Custom payment options ('hide PayPal if cart total >$500'). Cart validation server-side (no checkout button if banned region).
Who actually needs it
Brands above $500K MRR with specific checkout-customization requirements that can't be done via apps. Most sub-$500K brands don't need it — the dev cost ($5-15K for a function) outweighs the gain.
The tools worth comparing
- Shopify — Platform requirement for most AI ad tools — they integrate Shopify first.
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