> ## Documentation Index
> Fetch the complete documentation index at: https://mw-docs.middleware.io/llms.txt
> Use this file to discover all available pages before exploring further.
# Browser RUM - Next.js
> Next.js RUM - Setup & Installation Docs | Middleware
# Install
When using Next.js, you do not have direct access to the `index.html` or template HTML file. You must define the structure of your RUM application with one of the following methods:
### App Router
Define the structure of your application with app routers.
Click [here](https://nextjs.org/docs/app/building-your-application/optimizing/third-party-libraries) for more information on integrating third party libraries with Next.js using app structure.
Apply the following script to your application code:
```javascript Next.js theme={null}
import Script from "next/script"
export default function RootLayout({
children,
}: {
children: React.ReactNode
}) {
return (
{children}
)
}
```
### Page Router
Define the structure of your application with page structure.
Click [here](https://nextjs.org/docs/pages/building-your-application/optimizing/scripts) for more information on integrating third party libraries with Next.js using page structure.
Apply the following script to your application code:
```javascript Next.js theme={null}
import Script from 'next/script'
export default function MyApp({ Component, pageProps }) {
return (
<>
)
}
```