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+# sf-auth-nextjs-middleware
+
+Nextjs middleware and App Router callback handler for sf-auth.
+
+## Install
+
+```bash
+npm install sf-auth-nextjs-middleware
+```
+
+## Usage
+
+### Middleware
+
+Create a middleware that redirects unauthenticated users to the sf-auth
+authenticate endpoint.
+
+```ts
+// middleware.ts
+import { createSfAuthMiddleware } from "sf-auth-nextjs-middleware";
+
+export const middleware = createSfAuthMiddleware(
+  "https://your-site.com/auth_callback"
+);
+```
+
+### Callback route
+
+Create an App Router route to handle the sf-auth callback, validate the
+one-time key, set cookies, and redirect to the desired page.
+
+```ts
+// app/auth_callback/route.ts
+import { createSfAuthCallbackRoute } from "sf-auth-nextjs-middleware";
+
+export const GET = createSfAuthCallbackRoute({
+  redirectTo: "/user_info"
+});
+```
+
+## Configuration
+
+Both helpers accept optional configuration to customize cookie names and
+endpoints.
+
+```ts
+import {
+  createSfAuthMiddleware,
+  createSfAuthCallbackRoute
+} from "sf-auth-nextjs-middleware";
+
+export const middleware = createSfAuthMiddleware(
+  "https://your-site.com/auth_callback",
+  {
+    cookieNames: {
+      userId: "sf_user_id",
+      username: "sf_username"
+    }
+  }
+);
+
+export const GET = createSfAuthCallbackRoute({
+  redirectTo: "/user_info",
+  cookieNames: {
+    userId: "sf_user_id",
+    username: "sf_username"
+  },
+  validateEndpoint: "https://snazzyfellas.com/api/redirect/validate"
+});
+```