diff --git a/legacy/application/common/HTTPHelper.php b/legacy/application/common/HTTPHelper.php
index 3047685cc..11780c5ed 100644
--- a/legacy/application/common/HTTPHelper.php
+++ b/legacy/application/common/HTTPHelper.php
@@ -63,7 +63,7 @@ class ZendActionHttpException extends Exception
         $statusCode,
         $message,
         $code = 0,
-        Exception $previous = null
+        ?Exception $previous = null
     ) {
         Logging::error('Error in action ' . $action->getRequest()->getActionName()
             . " with status code {$statusCode}: {$message}");
diff --git a/legacy/application/logging/AirtimeLog.php b/legacy/application/logging/AirtimeLog.php
index 5759936b8..e27493d12 100644
--- a/legacy/application/logging/AirtimeLog.php
+++ b/legacy/application/logging/AirtimeLog.php
@@ -17,7 +17,7 @@ class Airtime_Zend_Log extends Zend_Log
      */
     protected $_origErrorHandler;
 
-    public function __construct(Zend_Log_Writer_Abstract $writer = null)
+    public function __construct(?Zend_Log_Writer_Abstract $writer = null)
     {
         parent::__construct($writer);
     }
diff --git a/legacy/application/models/airtime/CcShow.php b/legacy/application/models/airtime/CcShow.php
index 02c6c569e..81f44f817 100644
--- a/legacy/application/models/airtime/CcShow.php
+++ b/legacy/application/models/airtime/CcShow.php
@@ -42,7 +42,7 @@ class CcShow extends BaseCcShow
      *
      * @throws PropelException
      */
-    public function getFirstCcShowDay($criteria = null, PropelPDO $con = null)
+    public function getFirstCcShowDay($criteria = null, ?PropelPDO $con = null)
     {
         /*CcShowPeer::clearInstancePool();
         CcShowPeer::clearRelatedInstancePool();*/
@@ -161,7 +161,7 @@ class CcShow extends BaseCcShow
      *
      * @throws PropelException
      */
-    public function getFutureCcShowInstancess($criteria = null, PropelPDO $con = null)
+    public function getFutureCcShowInstancess($criteria = null, ?PropelPDO $con = null)
     {
         if (null === $this->collCcShowInstancess || null !== $criteria) {
             if ($this->isNew() && null === $this->collCcShowInstancess) {
@@ -246,7 +246,7 @@ class CcShow extends BaseCcShow
      *
      * @throws PropelException
      */
-    public function getCcShowInstancess($criteria = null, PropelPDO $con = null)
+    public function getCcShowInstancess($criteria = null, ?PropelPDO $con = null)
     {
         return CcShowInstancesQuery::create(null, $criteria)
             ->filterByCcShow($this)
diff --git a/legacy/application/models/airtime/CcShowInstances.php b/legacy/application/models/airtime/CcShowInstances.php
index 0a495a833..30cd519a9 100644
--- a/legacy/application/models/airtime/CcShowInstances.php
+++ b/legacy/application/models/airtime/CcShowInstances.php
@@ -192,7 +192,7 @@ class CcShowInstances extends BaseCcShowInstances
         $this->save($con);
     }
 
-    public function preInsert(PropelPDO $con = null)
+    public function preInsert(?PropelPDO $con = null)
     {
         $now = new DateTime('now', new DateTimeZone('UTC'));
         $this->setDbCreated($now);
diff --git a/legacy/application/modules/rest/controllers/RouteController.php b/legacy/application/modules/rest/controllers/RouteController.php
index 0b3482a1c..4d9b61b87 100644
--- a/legacy/application/modules/rest/controllers/RouteController.php
+++ b/legacy/application/modules/rest/controllers/RouteController.php
@@ -24,7 +24,7 @@ class Rest_RouteController extends Zend_Controller_Router_Route
      * @param Zend_Translate        $translator Translator to use for this instance
      * @param null|mixed            $locale
      */
-    public function __construct(Zend_Controller_Front $front, $route, $defaults = [], $reqs = [], Zend_Translate $translator = null, $locale = null)
+    public function __construct(Zend_Controller_Front $front, $route, $defaults = [], $reqs = [], ?Zend_Translate $translator = null, $locale = null)
     {
         $this->_front = $front;
         $this->_dispatcher = $front->getDispatcher();
diff --git a/legacy/tools/composer.json b/legacy/tools/composer.json
index ad0f37c53..96b9bd134 100644
--- a/legacy/tools/composer.json
+++ b/legacy/tools/composer.json
@@ -1,6 +1,6 @@
 {
   "require": {
     "php": "^7.4",
-    "friendsofphp/php-cs-fixer": "<3.51.1"
+    "friendsofphp/php-cs-fixer": "<3.53.1"
   }
 }