# Send the payment-failed email from a Replit app (React and Express, BuildBase sign-in)

Turn on the email BuildBase sends when a card fails, plus one prompt for a signed webhook route in a Replit Agent app for your own side effects.

Replit can also connect to BuildBase itself while it builds: [Use BuildBase in Replit](/console/ai-agents/replit).

When a renewal fails, BuildBase emails the workspace owner from your sending domain. That needs no code, only two switches in the console. The prompt adds a webhook route for what you want to happen besides, such as flagging the workspace, verified with your webhook secret. This page assumes the app already signs people in with @buildbase/sdk, as the [Replit guide](https://www.buildbase.app/guides/add-login-teams-and-paid-plans-to-a-replit-app) sets up. If it signs people in with something else, such as Supabase or Clerk, read [keep your existing sign-in](/sign-in-setup/keep-your-sign-in) first.

> **Note:**
  A sender connected ([connect a sender](/email/connect-a-sender)) and the
  **Payment Failed** notification event switched on
  ([notification events](/notifications/events)). For the route, an endpoint at
  `https://your-app.replit.app/api/webhooks/buildbase` under **Settings** >
  **Webhooks**, with `payment.failed` ticked ([add an
  endpoint](/webhooks/add-an-endpoint)).

## The prompt

[Open in Replit](https://replit.com/?stack=Build&prompt=CoCwlgzgBAhgDnKEwHMB204FMD2cA2WUYaUA7mAC4hQBCArmPgCa0wREAUAAgEaMte7LAHoIzANYBKADRIslKPUTsoISpTgQAXCJFkDAOn5NmQjofhwRKRsywQRMZswC0+HChKvKWGAFsIVxg0NzgYMDD8EKDKHGDXACcsAipghCQQHDIIQygASQAzYkVmHAcoNBxKOQg4lVCoX3x8KH8sQwAoACU-ZjUNLV0RMoBjXJNBYUsEfSxeLJwJRxwANyxE1bAsMkN-fsKwRLrYRrLK6uI0dbRFLBvFNACHLoBBF3lNjZFJs2FXMjzRYSQyUaAhfr+HD0W4lK6fdaJEQkewAD1B4PBCEMcBwdU4AHInHAwHMFjglo5fuYsAS5FhUXBkhBcokYGROABvJoAT2w2igBKs+DAoxglDAODQIgAVhApQSoABfWRQanCADqQIp0jkvCwhRwySgDKZDlycqlnCkeQAahswIUeXCKNQoOFjlgteSlgBRB5QQqJHD+KB8AR-DhiSRQKVQZIAR2MOGYPNBOAAypREiQUIT6JRCgAOAmq6hEVGudUcVzIdDi+jGiFQSvVrA+MDtOoBRAgPobcGNWgAVXyABkACK0V4Z30AfQ1vtoAAkAPKrgDSc9nAGFur7gIHg6GM1hRskwQBuU4QQGJKAAFgADABGch90hUeMKRsYSr0FoulXUhwh5dpbkMQoIkIZg5EKaIUCaPtyCNZZwlGIgSCgXpUkUCdxRgGlr3OKpFA4RoQhNfxoLkBhTDYDh5FCaAqDyV4MDvKAACYnyfJocBNRFnWqPt73uLAIKAA&referrer=docs.buildbase.app)

The link opens Replit Agent with the prompt filled in, for a new app; you still send it yourself. For the app you already have, paste the prompt into Agent's chat in that project instead.

```text
This app signs people in with BuildBase (@buildbase/sdk), set up as https://www.buildbase.app/guides/add-login-teams-and-paid-plans-to-a-replit-app shows. If it does not, stop and tell me.
Read https://docs.buildbase.app/webhooks/overview.md first and do not invent event names.
Add server/buildbase-webhook.ts and mount it in server/index.ts as app.post('/api/webhooks/buildbase', express.raw({ type: 'application/json' }), buildbaseWebhook), before express.json(). Verify it with parseWebhookEvent from @buildbase/sdk on req.body.toString('utf8'), the x-buildbase-signature and x-buildbase-timestamp headers and BUILDBASE_WEBHOOK_SECRET from Secrets; answer 401 when it returns null.
On payment.failed, flag the workspace in Replit Database; do not send an email, BuildBase sends it. Answer 200 to every other event.
```

## Where the secrets go

The console shows the endpoint's signing secret once, when you create it. Add it as `BUILDBASE_WEBHOOK_SECRET` in the Secrets tool (**Tools** > **Secrets**), and again under **Publishing** > **Adjust settings** > **Production app secrets**, then republish. Replit's docs say secrets set in the editor do not carry over to the published app.

## The Replit trap

Agent's app-wide `express.json()` parses the body before a webhook route registered after it sees the raw bytes, and the signature no longer matches: every delivery answers 401. Mount the webhook route with `express.raw` above `express.json()`, as the prompt says.

A 401 in the console's delivery log after that means the secret is in the editor's Secrets but not in Production app secrets.

## Full guides

- [Add login, teams and paid plans to a Replit Agent app](https://www.buildbase.app/guides/add-login-teams-and-paid-plans-to-a-replit-app)
- [Failed payments](/billing/failed-payments): retries, grace days and the emails
- [Add BuildBase to Replit as a skill](/ai-builders/replit-import)