`compression()` gzips HTTP response bodies with the native `Bun.gzipSync` binding when the client advertises `Accept-Encoding: gzip`. `Bun.serve` never compresses on its own — without this plugin every byte goes over the wire raw, no matter how large the JSON.

## Quick start

```typescript title="src/app.ts"
import { oke } from "okengine";
import { compression } from "okengine/plugins";

export const app = oke({ name: "shop", env: "dev" }).plug(compression());
```

A client sending `Accept-Encoding: gzip` now receives `Content-Encoding: gzip` with a `Vary: Accept-Encoding` marker; a client that does not ask gets the untouched body.

## Options

| Option    | Type     | Default                                      | Does                                                                    |
| --------- | -------- | -------------------------------------------- | ----------------------------------------------------------------------- |
| `minSize` | `number` | `1024`                                       | Bodies smaller than this pass through raw (gzip can grow tiny payloads) |
| `match`   | `RegExp` | JSON · `+json` · javascript · xml · `text/*` | Which `Content-Type`s are compressible                                  |

```typescript
.plug(compression({ minSize: 0 })) // compress even tiny bodies (tests, debugging)
```

## Notes

| Behavior          | Detail                                                                 |
| ----------------- | ---------------------------------------------------------------------- |
| Negotiation       | Runs only when `Accept-Encoding` allows gzip — `gzip;q=0` is respected |
| Already encoded   | Skips responses that already carry `Content-Encoding`                  |
| `no-transform`    | Skips responses whose `Cache-Control` forbids transformation           |
| Content-Length    | Deleted after compression — stale lengths would corrupt the response   |
| Non-HTTP triggers | No-op — nothing to compress outside HTTP                               |

## Runtime configuration

Thresholds and matchers can follow the database like every other official plugin — pass a `configSource()` as the options. See [Plugins → Runtime configuration](/docs/reference/plugins#runtime-configuration-code-or-db) for the full contract.

## Next

<Cards>
  <Card
    title="Headers"
    description="The full secure-headers set on every response."
    href="/docs/plugins/headers"
  />
  <Card
    title="IP Allowlist"
    description="Allow/deny rules by client IP."
    href="/docs/plugins/ip-allowlist"
  />
  <Card title="Plugin API" description="Build your own plugin." href="/docs/reference/plugins" />
</Cards>