diff --git a/composer.json b/composer.json
index 5e42df9b..0bcf72af 100644
--- a/composer.json
+++ b/composer.json
@@ -1,12 +1,12 @@
 {
     "name": "ddeboer/imap",
     "description": "Object-oriented IMAP for PHP",
+    "license": "MIT",
     "keywords": [
         "email",
         "mail",
         "imap"
     ],
-    "license": "MIT",
     "authors": [
         {
             "name": "David de Boer",
@@ -28,13 +28,13 @@
         "ext-mbstring": "*"
     },
     "require-dev": {
-        "friendsofphp/php-cs-fixer": "^v3.3.2",
+        "friendsofphp/php-cs-fixer": "^v3.4.0",
         "laminas/laminas-mail": "^2.15.1",
         "malukenho/mcbumpface": "^1.1.5",
-        "phpstan/phpstan": "^1.2.0",
+        "phpstan/phpstan": "^1.3.3",
         "phpstan/phpstan-phpunit": "^1.0.0",
         "phpstan/phpstan-strict-rules": "^1.1.0",
-        "phpunit/phpunit": "^9.5.10"
+        "phpunit/phpunit": "^9.5.11"
     },
     "autoload": {
         "psr-4": {
@@ -45,5 +45,10 @@
         "psr-4": {
             "Ddeboer\\Imap\\Tests\\": "tests/"
         }
+    },
+    "config": {
+        "allow-plugins": {
+            "malukenho/mcbumpface": true
+        }
     }
 }
diff --git a/phpunit.xml.dist b/phpunit.xml.dist
index b035235c..24ee738a 100644
--- a/phpunit.xml.dist
+++ b/phpunit.xml.dist
@@ -7,6 +7,9 @@
         colors="true"
         verbose="true"
 >
+  <php>
+    <ini name="error_reporting" value="E_ALL"/>
+  </php>
   <coverage>
     <include>
       <directory suffix=".php">./src</directory>
diff --git a/src/Connection.php b/src/Connection.php
index d9f2bb68..9f5ef90f 100644
--- a/src/Connection.php
+++ b/src/Connection.php
@@ -117,6 +117,7 @@ public function getMailbox(string $name): MailboxInterface
         return new Mailbox($this->resource, $name, $this->mailboxNames[$name]);
     }
 
+    #[\ReturnTypeWillChange]
     public function count()
     {
         $return = \imap_num_msg($this->resource->getStream());
diff --git a/src/Mailbox.php b/src/Mailbox.php
index 2f77799f..38823fee 100644
--- a/src/Mailbox.php
+++ b/src/Mailbox.php
@@ -64,6 +64,7 @@ public function getDelimiter(): string
         return $this->info->delimiter;
     }
 
+    #[\ReturnTypeWillChange]
     public function count()
     {
         $return = \imap_num_msg($this->resource->getStream());
diff --git a/src/Message/AbstractPart.php b/src/Message/AbstractPart.php
index 0ab0ca58..0647133c 100644
--- a/src/Message/AbstractPart.php
+++ b/src/Message/AbstractPart.php
@@ -268,6 +268,7 @@ final public function getParts(): array
      *
      * @return mixed
      */
+    #[\ReturnTypeWillChange]
     final public function current()
     {
         $this->lazyParseStructure();
@@ -275,11 +276,13 @@ final public function current()
         return $this->parts[$this->key];
     }
 
+    #[\ReturnTypeWillChange]
     final public function getChildren()
     {
         return $this->current();
     }
 
+    #[\ReturnTypeWillChange]
     final public function hasChildren()
     {
         $this->lazyParseStructure();
@@ -290,21 +293,25 @@ final public function hasChildren()
     /**
      * @return int
      */
+    #[\ReturnTypeWillChange]
     final public function key()
     {
         return $this->key;
     }
 
+    #[\ReturnTypeWillChange]
     final public function next()
     {
         ++$this->key;
     }
 
+    #[\ReturnTypeWillChange]
     final public function rewind()
     {
         $this->key = 0;
     }
 
+    #[\ReturnTypeWillChange]
     final public function valid()
     {
         $this->lazyParseStructure();