diff --git a/resources/build.defaults.yaml b/resources/build.defaults.yaml
index a0749ab..58c67f5 100644
--- a/resources/build.defaults.yaml
+++ b/resources/build.defaults.yaml
@@ -6,6 +6,5 @@ php:
 
 experimental:
   runStaticAnalysisOnTests: false
-  useNewDatabaseCredentials: true
 
 project_root: /app
diff --git a/src/DataTransferObject/ConfigDto.php b/src/DataTransferObject/ConfigDto.php
index 91f562f..4e2fe71 100644
--- a/src/DataTransferObject/ConfigDto.php
+++ b/src/DataTransferObject/ConfigDto.php
@@ -131,11 +131,6 @@ final class ConfigDto
             'runStaticAnalysisOnTests' => new Assert\Optional([
                 new Assert\Type('bool'),
             ]),
-
-            // TODO: remove this when its been removed from all `build.yaml` files.
-            'useNewDatabaseCredentials' => new Assert\Optional([
-                new Assert\Type('bool'),
-            ]),
         ],
     )]
     public array $experimental;
diff --git a/templates/php/drupal/.env.example.twig b/templates/php/drupal/.env.example.twig
index 1d15149..ed84f59 100644
--- a/templates/php/drupal/.env.example.twig
+++ b/templates/php/drupal/.env.example.twig
@@ -9,12 +9,6 @@ export COMPOSE_PROFILES=web,php,database
 export DOCKER_WEB_VOLUME=.:{{ project_root }}
 {% endif %}
 
-{% if experimental.useNewDatabaseCredentials %}
 export MYSQL_DATABASE=app
 export MYSQL_PASSWORD=app
 export MYSQL_USER=app
-{% else %}
-export MYSQL_DATABASE=drupal
-export MYSQL_PASSWORD=drupal
-export MYSQL_USER=drupal
-{% endif %}
diff --git a/tests/snapshots/configs/drupal-localgov.yaml b/tests/snapshots/configs/drupal-localgov.yaml
index f5ac074..cd8ff79 100644
--- a/tests/snapshots/configs/drupal-localgov.yaml
+++ b/tests/snapshots/configs/drupal-localgov.yaml
@@ -32,6 +32,3 @@ dockerfile:
         - composer install
       extra_directories:
         - assets
-
-experimental:
-  useNewDatabaseCredentials: true