Stripe Integration for Next.js, Done Right

App Router changes more about a Stripe integration than most teams expect going in. Server Actions replace the old "create an API route just to POST a form" pattern for simple cases, and Route Handlers take over the webhook and callback surface — but the runtime configuration on that webhook handler is the detail that breaks nearly every first attempt.

The App Router Details That Actually Matter

• Webhook signature verification needs the raw request body and Node.js crypto — explicitly set `export const runtime = "nodejs"` on that route, or it silently fails on Edge
• Server Actions are the cleanest way to create a Checkout Session from a form submission, with no separate API route needed
• Parallel/intercepting routes can model a Checkout modal without losing the underlying page's URL — useful for embedded upgrade flows
• Revalidate subscription-status-dependent pages after a webhook fires, via `revalidatePath` or `revalidateTag`, so cached pages don't show stale plan state

We default new Next.js Stripe integrations to App Router idioms rather than porting a Pages Router pattern into it, because most of the friction we're brought in to fix on existing projects traces back to exactly that mismatch — API route habits fighting against Server Actions and Route Handlers instead of using them.