# Request Context

The `context` object is a shared mutable object that passes through the middleware chain and eventually arrives at your `loader` or `action`.

## Populating Context

Middleware can add data to the context.

```ts
// src/middleware.ts
export const middleware = [
  async (request, context, next) => {
    const user = await getUserFromSession(request);
    
    // Add user to context
    context.user = user;
    
    return next();
  }
];
```

## Consuming Context

Your route handlers can then access this data.

```tsx
// src/routes/dashboard.tsx
export async function loader({ context }: LoaderArgs) {
  // Access data set by middleware
  const user = context.user;
  
  return { user };
}
```

This pattern is ideal for authentication (passing the user object) or dependency injection (passing a database client).