Adding Dependencies for the Server App

In order to get our server app working correctly, we need to make sure we load two of Angular's dependencies: zone.js and reflect-metadata.

Our browser app loads these dependencies using polyfills.ts, and for the server app, we will add them to src/main.server.ts.

Another dependency that we need to add is the ModuleMapLoaderModule. This is a third-party module that is needed to make Angular Universal apps work with lazy loading.

We will import two dependencies in src/main.server.ts so that they are imported when the AppServerModule is loaded.

Additionally, we will enable production mode, just like it's done for the browser app in src/main.ts:

1. Open the newly created file src/main.server.ts.

2. Add the imports at the top of the file:

   import 'zone.js/dist/zone-node';
   import 'reflect-metadata';
   
   import { enableProdMode } from '@angular/core';
   import { environment } from './environments/environment';

3. Conditionally enable production mode, depending on the environment...