Right way to change $base_url on Drupal 8

Hi,
On Drupal 7 inside settings.php had the option to modify the $base_url,
On Drupal 8 inside settings.php if I append the new $base_url every thing is working as exepected, But ,
What is the right way for that?
I read about symfony etc..
There is right way to do it manually?
Thanks