diff --git a/DEVELOPING.md b/DEVELOPING.md
index 9a8e3745397e9f7fb8ce0c86518aa774bc99f6ae..99f277518575a4fd6e7731329106a80252c17e3f 100644
--- a/DEVELOPING.md
+++ b/DEVELOPING.md
@@ -42,7 +42,8 @@ Several details of your setup can be customized via environment variables. Set t
 DRUPAL_CORE_BRANCH="9.5.x" # The branch of Drupal core that will be installed.
 DRUPAL_CORE_SHALLOW_CLONE="TRUE" # Whether or not to do a "shallow clone" of Drupal core. (Defaults to TRUE.) See note below.
 AUTOMATIC_UPDATES_BRANCH="8.x-2.x" # The branch of the Automatic Updates module that will be installed.
-SITE_DIRECTORY="auto-updates-dev" # The path to the directory where the dev environment will be installed.
+SITE_DIRECTORY="auto_updates_dev" # The path to the directory where the dev environment will be installed.
+SITE_HOST=".test" # The path for Drupal's TRUSTED_HOST_PATTERN.
 ```
 
 Note: A shallow Git clone is much smaller and therefore faster, but it removes the ability to do debugging operations such as `git bisect` or `git blame`. To recover these abilities, [you can convert your repository to a full clone after the fact](https://stackoverflow.com/questions/6802145/how-to-convert-a-git-shallow-clone-to-a-full-clone):