diff --git a/docker/php/entrypoint.sh b/docker/php/entrypoint.sh
index 72b26bc..e63a6ed 100644
--- a/docker/php/entrypoint.sh
+++ b/docker/php/entrypoint.sh
@@ -56,26 +56,13 @@ $DRUSH en -y views views_ui field_ui text options link datetime && \
   echo "[entrypoint] Core modules enabled." || echo "[entrypoint] WARNING: core modules failed."
 $DRUSH en -y webform webform_ui && \
   echo "[entrypoint] Webform enabled." || echo "[entrypoint] WARNING: webform failed."
-$DRUSH en -y symfony_mailer mailer_transport && \
+$DRUSH en -y symfony_mailer && \
   echo "[entrypoint] Mailer enabled." || echo "[entrypoint] WARNING: symfony_mailer failed."
 
-if [ -n "${POSTMARK_API_KEY:-}" ]; then
-  $DRUSH php:eval "
-    \$storage = \Drupal::entityTypeManager()->getStorage('mailer_transport');
-    if (!\$storage->load('postmark')) {
-      \$storage->create([
-        'id' => 'postmark',
-        'label' => 'Postmark',
-        'plugin' => 'dsn',
-        'configuration' => ['dsn' => 'postmark+api://' . getenv('POSTMARK_API_KEY') . '@default'],
-      ])->save();
-    }
-    \Drupal::configFactory()->getEditable('mailer_transport.settings')
-      ->set('default_transport', 'postmark')->save();
-    \Drupal::configFactory()->getEditable('system.mail')
-      ->set('interface.default', 'symfony_mailer')->save();
-  " && echo "[entrypoint] Postmark transport configured." || { echo "[entrypoint] FATAL: Postmark transport setup failed."; exit 1; }
-fi
+# Mail transport is configured via $config['system.mail']['mailer_dsn'] in settings.php,
+# which is read directly by Drupal core's symfony_mailer mail plugin.
+# Do NOT use the mailer_transport module's entity system for this — it is only a UI layer
+# and is not consulted by core when actually sending mail.
 $DRUSH en -y riverside_pt && \
   echo "[entrypoint] riverside_pt enabled." || echo "[entrypoint] WARNING: riverside_pt failed."
 
diff --git a/web/sites/default/settings.php b/web/sites/default/settings.php
index e7084dc..1a889bf 100644
--- a/web/sites/default/settings.php
+++ b/web/sites/default/settings.php
@@ -20,11 +20,23 @@ $settings['hash_salt'] = getenv('HASH_SALT') ?: 'replace-this-in-production';
 $settings['update_free_access'] = FALSE;
 
 $is_dev = (bool) getenv('DEBUG');
+$postmark_key = getenv('POSTMARK_API_KEY');
 
 if ($is_dev) {
   $config['system.mail']['interface']['default'] = 'php_mail';
-} elseif (!getenv('POSTMARK_API_KEY')) {
-  throw new \RuntimeException('POSTMARK_API_KEY is not set — refusing to start without a mail transport.');
+} else {
+  if (!$postmark_key) {
+    throw new \RuntimeException('POSTMARK_API_KEY is not set — refusing to start without a mail transport.');
+  }
+  $config['system.mail']['interface']['default'] = 'symfony_mailer';
+  $config['system.mail']['mailer_dsn'] = [
+    'scheme'   => 'postmark+api',
+    'host'     => 'default',
+    'user'     => $postmark_key,
+    'password' => NULL,
+    'port'     => NULL,
+    'options'  => [],
+  ];
 }
 
 // Disable CSS/JS aggregation — assets served directly from source paths.