# WorkerdBackgroundTaskProvider

## Import

```typescript
import { WorkerdBackgroundTaskProvider } from "alepha/background";
```

## Overview

Cloudflare Workers variant of `BackgroundTaskProvider`.

Cloudflare freezes the isolate once the response is returned, so a plain
fire-and-forget promise would be killed mid-flight. The platform exposes a
per-invocation `executionCtx.waitUntil(promise)` that keeps the isolate alive
until `promise` settles; the `fetch`, `scheduled` and `queue` entry points
(generated by the Cloudflare build) stash it in the invocation's async context
under `cloudflare.waitUntil`.

This is the ONE place that reads that key - call sites use
`BackgroundTaskProvider.defer` and stay platform-agnostic.

`waitUntil` belongs to one invocation, so `defer()` must be called within
that async context (which is where background work is scheduled, a cron tick
included). Outside it the key is absent and we fall back to the base
fire-and-track behaviour.