# Mounting the App

URL: /code/learn/mounting-the-app · Id: `page:code/learn/mounting-the-app`

> Tutorial 7 of 12 mounts Leaseline's portal App over the lease Noun, with what each persona may do and one view override.

An [App](/business/nouns/app) is an [Interface](/business/nouns/interface) over the [Nouns](/business/nouns/noun), so its screens derive from them. Leaseline declares a `Lease` Noun, and the portal gives managers and residents their own screens.

## What you build
You mount `apps/portal/` at `/app` with two [Personas](/business/nouns/persona): managers run every [Verb](/business/nouns/verb), residents read and answer. Then you override one screen, the lease detail.

## Steps
1. To mount the App, write its folder file:

   ```mdx title="apps/portal/app.mdx"
   ---
   kind: saas
   mount: /app
   nouns: [Lease]
   personas:
     manager: { may: [Lease.create, Lease.renew, Lease.notify] }
     resident: { may: [Lease.get] }
   ---
   ```

2. To open the screens it derived, visit the preview at `/app/leases`, then one lease, then `/app/leases/lease_4loEed1JG4/renew`.

3. To change the lease screen, write a view at its path:

   ```mdx title="apps/portal/leases/[lease]/view.mdx"
   ---
   personas: [manager]
   ---
   <ThingDetail />
   <Timeline />
   <VerbSheet verb="Lease.renew" />
   <VerbSheet verb="Lease.notify" />
   ```

   In a view, `ThingDetail` and `Timeline` show the record its route names. Each `VerbSheet` turns one Verb into fields and a button, with its [Mode](/business/nouns/mode), its [Price](/business/nouns/price) and any [Approval](/business/nouns/approval) it needs.

## Result
The portal serves a list and a record screen for leases and a form for each Verb, and residents see only what they may read. The view override replaced one screen and left the rest derived. Checkpoint `leaseline@ch07` (status `planned`) adds `apps/portal/`.

## Next steps
- [Tutorial 8](/code/learn/automating-the-notice) sends the notice without anyone clicking.
- [Apps](/code/file-conventions/apps) and [views](/code/file-conventions/views): the full contracts.