Ecommerce

Edge Requests dominate (catalog browsing, image asset traffic) → Image Optimization (product images) → Function Duration (cart/checkout APIs). ISR Reads matter when product pages use ISR.

Priority patterns

1. Catalog pages: aggressive ISR + image optimization. Product list and product detail pages should be ISR with a sensible revalidate (60s-3600s). Every image should go through next/image (or the framework equivalent). For Vercel-hosted storefronts, image cost can dominate everything else.
2. Checkout: keep dynamic, but parallelize external calls. Cart/checkout/payment routes are correctly dynamic. The win is in reducing their function duration — Promise.all for independent calls to Stripe + inventory + tax services. Cite vercel-react-best-practices:async-parallel.
3. Cart drawer hydration: lift 'use client' to the leaf. Cart components are interactive, but the page wrapping them shouldn’t be. Hoist server-rendered parts upward; only the buttons/forms are client.
4. Webhooks: separate, not on the user path. Stripe/Shopify webhook handlers should live as their own routes with short duration limits. They don’t share traffic patterns with the storefront.
5. Edge middleware for A/B + region routing only. Catalog locale routing is a fine fit. Auth/cart state belongs in the dynamic page, not middleware.

Frequent gotchas

• Product images served raw. <img src={product.imageUrl}> for hundreds of variants costs more than the rest of the bill combined. Always next/image.
• force-dynamic on the storefront homepage. Often added during development to test cart-state behavior, never removed. Audit ruthlessly.
• Sequential Stripe calls. “Create customer” → “create subscription” → “create invoice” is often three sequential awaits where two could run in parallel.
• Bot traffic on product search. Marketing-driven traffic + bot traffic on search routes inflates edge request cost. Bot Protection often pays for itself within a month.

Cross-references

• vercel-react-best-practices:async-parallel — parallelize Stripe/inventory/tax calls in checkout
• vercel-react-best-practices:async-suspense-boundaries — stream the checkout shell, fill cart drawer later
• vercel-react-best-practices:bundle-defer-third-party — defer analytics (GA, Mixpanel) post-hydration
• https://nextjs.org/docs/app/api-reference/components/image — for the catalog image fix
• https://vercel.com/docs/bot-management — for bot traffic on search/product routes