# Function: deriveInboxSignKeyBytes()

```ts
function deriveInboxSignKeyBytes(contactKey, gen): Promise<Uint8Array<ArrayBufferLike>>;
```

Defined in: [packages/core/src/identity/contact-key.ts:85](https://github.com/leifriksheim/minca/blob/main/core/src/identity/contact-key.ts#L85)

An inbox's signing key: signs the inbox and proves ownership to a relay. Separate, so no key both signs and decrypts.

## Parameters

| Parameter | Type |
| ------ | ------ |
| `contactKey` | `Uint8Array` |
| `gen` | `number` |

## Returns

`Promise`\<`Uint8Array`\<`ArrayBufferLike`\>\>