Source: https://dinakar-pageloop-knowledge-base.docs-staging.pageloop.ai

# Welcome to Kestrel

# Welcome to Kestrel

Kestrel is an event delivery service. You publish an event once; Kestrel delivers it to
every endpoint subscribed to that event type, retries on failure, and gives you a full
delivery log you can replay from.

> [!NOTE]
>
> Kestrel is a fictional product. This documentation exists as test data for Pageloop's
> knowledge base — the facts in it are invented, deliberately specific, and safe to contradict.

## What you get

- **Ordered delivery**

  Events published to the same stream key arrive at your endpoint in publish order.
- **Automatic retries**

  Failed deliveries are retried 5 times with exponential backoff. See [Delivery and retries](/concepts/delivery-and-retries).
- **Signed payloads**

  Every request carries an HMAC-SHA256 signature you can verify. See [Signatures](/concepts/signatures).
- **Replay**

  Any delivery from the last 30 days can be replayed from the dashboard or the API.

## How it fits together

![Your backend publishes to Kestrel, which fans out to each subscribed endpoint](https://d2qvcb9ffq0p5e.cloudfront.net/faf0698b-4136-4317-868c-d1aef034d8f4/images/703941d2906b71c118e40bd599d0ec49256320b5438675d204a2672f09d97afb.svg)

1. **Publish**

   Your backend calls `POST /v1/events` with a type and a payload.
2. **Fan out**

   Kestrel matches the event type against your subscriptions.
3. **Deliver**

   Each subscribed endpoint receives a signed `POST` within 200 ms of publish, on average.
4. **Confirm**

   Your endpoint returns `2xx`. Anything else is a failed delivery and enters the retry schedule.

## Before you start

You need an account and an API key. Keys are created in the dashboard under **Settings → API keys**
and are shown exactly once.

> [!WARNING]
>
> Publishable keys (prefix `pk_`) can only read event metadata. Publishing requires a
> secret key (prefix `sk_`). Never ship a secret key to a browser or mobile client.

Ready? Head to the [Quickstart](/quickstart).