How to set environment via `ng serve` in Angular 6

Question

I am trying to update my Angular 5.2 app to Angular 6. I successfully followed instructions in the Angular update guide (including the update of angular-cli to

Answer 1

Angular no longer supports --env instead you have to use

ng serve -c dev

for development environment and,

ng serve -c prod 

for production.

NOTE: -c or --configuration