diff --git a/CHANGELOG.md b/CHANGELOG.md
index e7c49fe..a304eb9 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -16,3 +16,4 @@
 * `App\Enum\Webserver` now returns a string.
 * `ConfigurationValidatorTest` no longer performs serialisation.
 * Use `set -o errexit` and `set -o pipefail` in `run` scripts instead of `set -eu`.
+* Use new database credentials by default.
diff --git a/resources/build.defaults.yaml b/resources/build.defaults.yaml
index ae494c7..8de91e4 100644
--- a/resources/build.defaults.yaml
+++ b/resources/build.defaults.yaml
@@ -2,6 +2,6 @@ drupal:
   docroot: web
 
 experimental:
-  useNewDatabaseCredentials: false
+  useNewDatabaseCredentials: true
 
 project_root: /app
diff --git a/src/DataTransferObject/Config.php b/src/DataTransferObject/Config.php
index 2d2d498..cb3e209 100644
--- a/src/DataTransferObject/Config.php
+++ b/src/DataTransferObject/Config.php
@@ -109,6 +109,7 @@ final class Config
             'runGitHooksBeforePush' => 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'),
             ]),