diff --git a/public_html/deployment/classes/messenger.class.php b/public_html/deployment/classes/messenger.class.php
index f888cefbadd64ea35d841a27788db0d6f4f80525..3e8caac7378a1b6856a3be6bb5450dad0486847f 100644
--- a/public_html/deployment/classes/messenger.class.php
+++ b/public_html/deployment/classes/messenger.class.php
@@ -4,70 +4,80 @@
  * send messenger notifications
  *
  * @author hahn
+ * 
+ * 2024-08-23  v1.1  Axel Hahn  php8 only; added variable types
  */
-class messenger {
+class messenger
+{
 
     /**
      * config array for messengers
-     * @var type 
+     * @var array 
      */
-    protected $_aCfg = array();
-    
+    protected array $_aCfg = [];
+
     /**
      * content of messagetext to send
      * @var string
      */
-    protected $_sMessage = '';
+    protected string $_sMessage = '';
 
     /**
+     * Constructor
      * 
      * @example
-     * $oMessenger = new messenger(array(
-     *   'slack'=>array(
+     * $oMessenger = new messenger([
+     *   'slack'=>[
      *     'incomingurl'=>[WebHook url],
      *     'user'=>[visible username in slack],
      *     'icon'=>[Slack Icon], // hm, does not seem to work
-     *   ),
-     *   'email'=>array(
+     *   ],
+     *   'email'=>[
      *     'from'=>[senders e-mail]
      *     'to'=>[email-address(es)] // multiple emails must be delimited with ";"
-     *   )
-     * ));
+     *   ]
+     * ]);
      * @param array $aCfg  config array for notification targets
-     * @return boolean
      */
-    public function __construct($aCfg) {
+    public function __construct(array $aCfg)
+    {
         $this->_aCfg = $aCfg;
-        return true;
     }
 
     /**
-     * send an email if _aCfg['email']['to'] exists
+     * Send an email if _aCfg['email']['to'] exists
+     * @return bool
      */
-    private function _sendEmail(){
+    private function _sendEmail(): bool
+    {
         if (isset($this->_aCfg['email']['to']) && $this->_aCfg['email']['to']) {
             preg_match('/^(.*)\n/', $this->_sMessage, $aTmp);
             $sSubject = $aTmp[0];
             return mail(
-                $this->_aCfg['email']['to'], 
-                $sSubject, $this->_sMessage, 
+                $this->_aCfg['email']['to'],
+                $sSubject,
+                $this->_sMessage,
                 "From: " . $this->_aCfg['email']['from'] . "\r\n" .
                 "Reply-To: " . $this->_aCfg['email']['from'] . "\r\n"
             );
         }
         return false;
     }
-    
+
     /**
-     * send a message to slack if _aCfg['slack']['incomingurl'] exists
+     * Send a message to slack if _aCfg['slack']['incomingurl'] exists
+     * @return bool|string
      */
-    private function _sendToSlack(){
+    private function _sendToSlack(): bool|string
+    {
         if (isset($this->_aCfg['slack']['incomingurl']) && $this->_aCfg['slack']['incomingurl']) {
             require_once(__DIR__ . '/../../vendor/shooker/shooker.php');
             $shkr = new Shooker();
             $shkr->setupIncoming($this->_aCfg['slack']['incomingurl']);
-            $sUser=(isset($this->_aCfg['slack']['user'])? $this->_aCfg['slack']['user']: false);
-            $sIcon=(isset($this->_aCfg['slack']['icon'])? $this->_aCfg['slack']['icon']: false);
+            $sUser = (isset($this->_aCfg['slack']['user']) ? $this->_aCfg['slack']['user'] : false);
+            $sIcon = (isset($this->_aCfg['slack']['icon']) ? $this->_aCfg['slack']['icon'] : false);
+
+            // returns bool or string with response from Slack API
             return $shkr->sendMessage($this->_sMessage, $sUser, $sIcon);
         }
         return false;
@@ -77,13 +87,14 @@ class messenger {
     /**
      * send a message to all targets
      * @param string $sMessage
+     * @return void
      */
-    public function sendMessage($sMessage) {
-        $this->_sMessage=$sMessage;
+    public function sendMessage(string $sMessage): void
+    {
+        $this->_sMessage = $sMessage;
         // echo '<pre>'.print_r($this->_aCfg, 1).'</pre>'.$sMessage.'<br>';
         $this->_sendEmail();
         $this->_sendToSlack();
-        
     }
 
 }