# Relay

> Send events and deliver webhooks with retries and signatures.

- [Introduction](https://relay-demo.mintlify.app/index.md): Relay sends your app's events to the services that need them, as signed webhooks that are retried until they arrive.
- [Quickstart](https://relay-demo.mintlify.app/quickstart.md): Send an event and receive it as a webhook on your machine.
- [Authentication](https://relay-demo.mintlify.app/authentication.md): Use an API key for your own account, or OAuth when your app acts for other Relay customers.
- [Send events](https://relay-demo.mintlify.app/sending-events.md): Send an event once and Relay delivers it to every endpoint that subscribed to its type.
- [Webhook delivery and retries](https://relay-demo.mintlify.app/webhooks/delivery.md): What counts as delivered, and what Relay does when your endpoint is down.
- [Verify signatures](https://relay-demo.mintlify.app/webhooks/signatures.md): Check that a webhook came from Relay and wasn't changed or replayed.
- [Idempotency](https://relay-demo.mintlify.app/idempotency.md): Retry a request safely without sending the same event twice.
- [Rate limits](https://relay-demo.mintlify.app/rate-limits.md): How many requests you can send, and what to do when you hit the limit.
- [Architecture overview](https://relay-demo.mintlify.app/architecture.md): How an event moves through Relay, from your request to your endpoint.
- [Node SDK](https://relay-demo.mintlify.app/sdks/node.md): Send events and verify webhooks from Node.js 18 or later.
- [CLI](https://relay-demo.mintlify.app/cli.md): Receive webhooks on localhost, send test events and replay failed deliveries.
- [API reference](https://relay-demo.mintlify.app/api-reference/introduction.md): The Relay REST API: base URL, endpoints and errors.


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