# Type Alias: FetchCreateContextFn()<TRouter>

> 

> **FetchCreateContextFn**\<`TRouter`\>: (`opts`) => [`inferRouterContext`](https://trpc.io/docs/typedoc/server/index/type-aliases/inferRouterContext.md)\<`TRouter`\> \| `Promise`\<[`inferRouterContext`](https://trpc.io/docs/typedoc/server/index/type-aliases/inferRouterContext.md)\<`TRouter`\>\>

Defined in: [packages/server/src/adapters/fetch/types.ts:34](https://github.com/trpc/trpc/blob/7c907acfd8b31929214792e3b8c2ad7a8ac72563/packages/server/src/adapters/fetch/types.ts#L34)

The `createContext` function the Fetch adapter takes.

## Type Parameters

| Type Parameter |
| ------ |
| `TRouter` *extends* [`AnyTRPCRouter`](https://trpc.io/docs/typedoc/server/index/type-aliases/AnyTRPCRouter.md) |

## Parameters

| Parameter | Type |
| ------ | ------ |
| `opts` | [`FetchCreateContextFnOptions`](https://trpc.io/docs/typedoc/server/adapters/fetch/type-aliases/FetchCreateContextFnOptions.md) |

## Returns

[`inferRouterContext`](https://trpc.io/docs/typedoc/server/index/type-aliases/inferRouterContext.md)\<`TRouter`\> \| `Promise`\<[`inferRouterContext`](https://trpc.io/docs/typedoc/server/index/type-aliases/inferRouterContext.md)\<`TRouter`\>\>