Serverless Stack

This is a stupid question - in the guide you say to do this:

```export default class ApiStack extends sst.Stack {
  api;

  constructor(scope, id, props) {
    super(scope, id, props);
    ...```
Why do we expose api? Is there any requirement of SST for us to do that?

only if you're passing it to another stack to reference

we need it because of this :
```  const apiStack = new ApiStack(app, 'api', {...});
  const authStack = new AuthStack(app, 'auth', {
    api: apiStack.api,
    uploadsBucket: storageStack.uploadsBucket,
  });```
?

Hum I removed the reference but it still works and detects no build change

Can I see how you are using the api inside the AuthStack?

```export default class AuthStack extends sst.Stack {
  auth;

  constructor(scope, id, props) {
    super(scope, id, props);

    const { api, uploadsBucket } = props;

    this.auth = new sst.Auth(this, 'Auth', { ... });

    this.auth.attachPermissionsForAuthUsers([
      api,
      // ...
    ]);
    // ...
  }
}```
