diff --git a/lib/tools/Debug.class.php b/lib/tools/Debug.class.php
index 3caa1d61..253c9bfb 100644
--- a/lib/tools/Debug.class.php
+++ b/lib/tools/Debug.class.php
@@ -2,24 +2,24 @@
 
 class Debug
 {
-  public static function exceptionToString(Exception $e)
+  public static function exceptionToString(Throwable $e)
   {
     return static::getExceptionMessageWithoutTrace($e) . "\n" . static::getFullTrace($e);
   }
 
-  public static function getExceptionMessageWithoutTrace(Exception $e)
+  public static function getExceptionMessageWithoutTrace(Throwable $e)
   {
     return 'exception \'' . get_class($e) . '\' with message \'' . $e->getMessage() . '\' in ' . $e->getFile() . ':' . $e->getLine();
   }
 
   /**
    * Same as the normal getTraceAsString(), but does not truncate long lines.
-   * @param Exception $exception
+   * @param Throwable $exception
    * @return string
    * @see http://stackoverflow.com/questions/1949345/how-can-i-get-the-full-string-of-phps-gettraceasstring/6076667#6076667
    * @see https://gist.github.com/1437966
    */
-  public static function getFullTrace(Exception $exception)
+  public static function getFullTrace(Throwable $exception)
   {
     $rtn = '';
     foreach ($exception->getTrace() as $count => $frame)
diff --git a/web/index.php b/web/index.php
index c56fb261..8f07dbcc 100644
--- a/web/index.php
+++ b/web/index.php
@@ -23,10 +23,15 @@ try
   }
   Controller::dispatch(strtok($_SERVER['REQUEST_URI'], '?'));
 }
-catch(Exception $e)
+catch(Throwable $e)
 {
   if (IS_PRODUCTION)
   {
+    $slackErrorNotificationUrl = Config::get('slack_error_notification_url');
+    if ($slackErrorNotificationUrl)
+    {
+      Curl::post($slackErrorNotificationUrl, ['text' => '<!everyone> ' . $e->__toString()], ['json_data' => true]);
+    }
     throw $e;
   }