# Create A Fund Client

The `CityFundClient` is your primary interface for all deposit and funding operations. Unlike `CityClient`, it does not require a wallet connection — it authenticates via an API key issued for your integration.

```
import { CityFundClient } from "@cityprotocol/core";

const fundClient = new CityFundClient({
  apiKey: process.env.FUN_API_KEY!,
});
```

> **Note:** Your `FUN_API_KEY` is a server-side secret tied to your fun.xyz integration. Never expose it in client-side bundles. See the **Backend Integration** section below for the recommended pattern.


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