Fastify

Fastify parses JSON before your route runs. Register verihookRawBody in the scope of your webhook routes: it keeps request.rawBody and still parses JSON and form bodies into request.body.

import Fastify from 'fastify';
import { verihookFastify, verihookRawBody, type VerihookFastifyRequest } from 'verihook/fastify';
import type { StripeEvent } from 'verihook';

const app = Fastify();
await app.register(verihookRawBody);

app.post(
  '/webhooks/stripe',
  { preHandler: verihookFastify('stripe', process.env.STRIPE_WEBHOOK_SECRET!) },
  async (request) => {
    const { event, eventType } = (request as typeof request & VerihookFastifyRequest<StripeEvent>).verihook!;
    return { received: true };
  },
);

To keep the raw-body parser away from the rest of your app, register it inside a plugin with only the webhook routes:

app.register(async (webhooks) => {
  await webhooks.register(verihookRawBody);
  webhooks.post('/webhooks/github', { preHandler: verihookFastify('github', secret) }, handler);
});

onError(result, request, reply) replaces the default failure reply.

What the adapter does

Situation	Response
Invalid, missing or expired signature	401 { error, code }, unless you pass onError
Duplicate event (with dedupeStore)	200 { received: true, duplicate: true }
Body over maxBodySize (default 2 MB)	413 { code: "PAYLOAD_TOO_LARGE" }
Exception during verification	500 with a generic message
Your handler throws or responds >= 500	The dedupe key is released so the retry is processed

All verification options (tolerance, dedupeStore, url, …) can be passed as the last argument. Pick your provider in Providers for the secret and the headers it sends.