# Webhooks

> Every alert as signed JSON to a URL you choose.

URL: https://pagerless.dev/integrations/webhooks
Updated: 2026-10-22

Each request carries `Pagerless-Signature: t=<unix time>,v1=<HMAC-SHA256>`. Compute the HMAC of `t + "." + body` with your webhook secret and compare it in constant time; reject old timestamps.

```js
import { createHmac, timingSafeEqual } from "node:crypto";

function verify(header, body, secret) {
  const { t, v1 } = Object.fromEntries(header.split(",").map((p) => p.split("=")));
  const mac = createHmac("sha256", secret).update(`${t}.${body}`).digest("hex");
  return Math.abs(Date.now() / 1000 - Number(t)) < 300 && timingSafeEqual(Buffer.from(mac), Buffer.from(v1));
}
```