diff --git a/maintain.class.php b/maintain.class.php
index ca1509d..de671ec 100644
--- a/maintain.class.php
+++ b/maintain.class.php
@@ -6,23 +6,37 @@ if (!defined('PHPWG_ROOT_PATH'))
 
 require_once(dirname(__FILE__) . '/include/database.class.php');
 require_once(dirname(__FILE__) . '/tools/watermark_profiles.inc.php');
+require_once(dirname(__FILE__) . '/include/dependencies.inc.php');
 
 class bratonien_tools_maintain extends PluginMaintain
 {
-  private function prepare()
+  private function prepare(&$errors = array())
   {
     bratonien_tools_create_tables();
     bratonien_tools_create_default_watermark_profiles();
+
+    $dependency_messages = array();
+    bratonien_tools_ensure_dependencies($dependency_messages);
+
+    // Dependency failures must not disable unrelated Bratonien Tools features.
+    // Store the current result so the administration can surface it later.
+    if (function_exists('conf_update_param'))
+    {
+      conf_update_param('bratonien_dependency_status', json_encode(array(
+        'checked_at' => time(),
+        'messages' => $dependency_messages,
+      )));
+    }
   }
 
   public function install($plugin_version, &$errors = array())
   {
-    $this->prepare();
+    $this->prepare($errors);
   }
 
   public function activate($plugin_version, &$errors = array())
   {
-    $this->prepare();
+    $this->prepare($errors);
   }
 
   public function deactivate()
@@ -31,7 +45,7 @@ class bratonien_tools_maintain extends PluginMaintain
 
   public function update($old_version, $new_version, &$errors = array())
   {
-    $this->prepare();
+    $this->prepare($errors);
   }
 
   public function uninstall()