# Next.js (App Router) (/getting-started/frameworks/nextjs)
butr is a client-side wallet library — it touches `window`, wallet
extensions, and `localStorage`. Under the App Router that means the provider
must be a client component.
## The `"use client"` boundary [#the-use-client-boundary]
The `demo-next` reference is EVM-only (no `@usebutr/svm` or `@usebutr/wallets` in the
bundle) — see [EVM-only setup](/guides/evm-only) for the install, chain
list, and bundle rationale. This page covers only what is specific to the App
Router. The provider module starts with `"use client"`:
```tsx title="src/wallet-provider.tsx"
"use client";
import type { ReactNode } from "react";
import { createWalletSource } from "@usebutr/core";
import { WalletManagerProvider, useDiscoveredWallets } from "@usebutr/react";
import { discoverEvmAdapters } from "@usebutr/evm";
// EVM-only: @usebutr/react + @usebutr/evm. No @usebutr/svm / @usebutr/wallets in the
// bundle — discovery is a WalletSource built from the EVM discoverer.
const evmDiscovery = createWalletSource(discoverEvmAdapters);
const WalletProvider = ({ children }: { children: ReactNode }) => (
{children}
);
export { WalletProvider, useDiscoveredWallets };
```
Mount it in the root layout (a Server Component importing a Client Component is
fine):
```tsx title="src/app/layout.tsx"
import type { ReactNode } from "react";
import { WalletProvider } from "../wallet-provider";
const RootLayout = ({ children }: { children: ReactNode }) => (
{children}
);
export default RootLayout;
```
Any page using butr hooks (`useConnectWallet`, `useActiveWallet`, …) must also
be `"use client"`.
## Chains without `@usebutr/wallets` [#chains-without-usebutrwallets]
EVM-only setups don't bundle `@usebutr/wallets`. Pull the chain list from
`@usebutr/evm` directly:
```tsx
import { EVM_CHAINS_LIST } from "@usebutr/evm";
const CHAINS_BY_PLATFORM = { evm: EVM_CHAINS_LIST, svm: [] as const };
```
Why this keeps Solana out of the bundle is covered in
[EVM-only setup](/guides/evm-only#the-bundle-guarantee).
## Want EVM + SVM instead? [#want-evm--svm-instead]
Use `autoDiscovery()` from `@usebutr/wallets` in a `"use client"` module — same as
[Vite](/getting-started/frameworks/vite), just with the directive at the top. See
[Provider setup](/guides/provider-setup) for the full pattern.
**Source:** `apps/demo-next/src/wallet-provider.tsx` in the [butr
repository](https://github.com/pedroapfilho/usebutr/tree/main/apps/demo-next). Run `pnpm dev --filter=demo-next` → `http://localhost:3000`.