The `@authdog/nextjs-app` SDK integrates Authdog with the Next.js App Router: a client provider, `useAuth`/`useUser` hooks, and server helpers for middleware and logout. It reads the [session](/docs/concepts/sessions-tokens) Authdog issues after a hosted sign-in.
## Install
```bash
npm install @authdog/nextjs-app
```
Supports Next.js 15/16 and React 18 or 19. Set two env vars: `NEXT_PUBLIC_PK_AUTHDOG` (the publishable `pk_...` key, client-side) and `PK_AUTHDOG` (server-side).
## Wrap your app
Mount `AuthdogProvider` in the root layout. On load it captures the `?token=` from the sign-in redirect, validates it, persists the session, and strips the token from the URL:
```tsx
// app/layout.tsx
import { AuthdogProvider } from "@authdog/nextjs-app/client"
export default function RootLayout({
children,
}: {
children: React.ReactNode
}) {
return (
{children}
)
}
```
## Read the user
`useUser` returns the current profile; `useAuth` returns just the token and auth state:
```tsx
"use client"
import { useUser } from "@authdog/nextjs-app"
export default function Dashboard() {
const { user, isLoading } = useUser()
if (isLoading) return null
if (!user) return
return Signed in as {user.email}
}
// useAuth() -> { token, isAuthenticated, isLoading }
```
## Server-side session
For server enforcement, `useAuthMiddleware(publicKey)` exchanges the redirect token for HttpOnly session cookies; `logoutHandler` clears them. Client hooks are presentational — the server session is the enforcement point:
```ts
// middleware.ts
import { useAuthMiddleware } from "@authdog/nextjs-app/server"
export default useAuthMiddleware(process.env.PK_AUTHDOG!)
```
Sign out on the client with `clearAuthdogSession()` followed by a reload, or route to a handler backed by `logoutHandler`. Pair the session with your [authorization](/docs/concepts/authorization) model to decide what a user may do.
## Next steps
- [Component reference](/docs/components) — the `@authdog/react-elements` UI used with the provider.
- [Backend requests](/docs/backend) — validate the same session on your API routes.
- [Quickstarts](/docs/quickstarts) — the five-minute path.