sfnext-revalidation

Storefront Next Revalidation

React Router re-runs loaders after every action submission. A storefront has deep route trees, persistent fetchers (mini-cart) and lazy modals (quick view), so one add-to-cart can re-run many loaders that never read the basket, each with its own SCAPI fan-out. This skill is how to keep only the re-runs that are needed. The authoritative guide is docs/README-REVALIDATION.md in your project; read it before changing policy.

What revalidates

An action submission (<Form>, useSubmit, fetcher.submit) re-runs the whole active set:

1. the matched route chain (root, layouts, leaf),
2. mounted resource fetchers (fetcher.load() of a resource route whose component is still mounted),
3. fetchers inside open modals, drawers and sheets.

A raw fetch(), a SCAPI client call, or fetcher.load() is not a submission and triggers nothing. A route that only exports an action fires revalidation but has no loader to re-run.

When a re-run is justified

For each pair (action, active loader) it is justified only if both are true:

• Overlap: the action result changes something the loader reads.
• Value not already available: the new value does not already reach the UI another way (for example the basket provider is updated from the action result, so a cart action does not need the PDP loader to re-run).

Two waste types: no overlap, or overlap with the value already available. Do not gate a re-run that is itself the sync mechanism (a provider that refills from loader output).

Where the policy lives

Each route re-exports a shared policy rather than inlining logic:

// src/routes/_app.cart.tsx
export { shouldRevalidate } from '@/lib/revalidation/routes/cart';

Module (src/lib/revalidation/routes/)	Used by
root.ts	src/root.tsx (export { shouldRevalidate } from ...); denylist of irrelevant mutations, safe default is revalidate
cart.ts, checkout.ts, home.ts, wishlist.ts	the matching route files
product.ts	_app.p.$.tsx: relevant mutations force true; navigation re-runs only on different path or pid
category.ts	_app.c.$.tsx and _app.search.tsx: skips client-only param changes and non-ambient mutations
api-client.ts	resource.api.client.$resource.ts
shared.ts	helpers: getActionPath, isContextMutation, isIdentityMutation, isAmbientMutation