# Grouping routes for RPC

If you want to enable type inference for multiple `app`s correctly, you can use `app.route()` as follows.

Pass the value returned from methods like `app.get()` or `app.post()` to the second argument of `app.route()`.

```ts
import { Hono } from 'hono'
import { hc } from 'hono/client'

const authorsApp = new Hono()
  .get('/', (c) => c.json({ result: 'list authors' }))
  .post('/', (c) => c.json({ result: 'create an author' }, 201))
  .get('/:id', (c) => c.json({ result: `get ${c.req.param('id')}` }))

const booksApp = new Hono()
  .get('/', (c) => c.json({ result: 'list books' }))
  .post('/', (c) => c.json({ result: 'create a book' }, 201))
  .get('/:id', (c) => c.json({ result: `get ${c.req.param('id')}` }))

const app = new Hono()
  .route('/authors', authorsApp)
  .route('/books', booksApp)

type AppType = typeof app
```

## See also

- [Guides - RPC - Client](/docs/guides/rpc#client)