diff --git a/composer.json b/composer.json
index 055621d..3e05a88 100644
--- a/composer.json
+++ b/composer.json
@@ -18,7 +18,7 @@
   "require": {
     "php": "^7.2 || ^8.0",
     "event-engine/php-schema": "^0.3.0",
-    "event-engine/php-engine-utils": "^0.2.1",
+    "event-engine/php-engine-utils": "^0.2.1 || ^1.0",
     "ramsey/uuid" : "^3.6|^4.0"
   },
   "require-dev": {
diff --git a/src/CommandDispatchResult.php b/src/CommandDispatchResult.php
index d6bcf6d..794c022 100644
--- a/src/CommandDispatchResult.php
+++ b/src/CommandDispatchResult.php
@@ -43,7 +43,7 @@ public static function forCommandHandledByController(Message $dispatedCommand):
         return new self($dispatedCommand);
     }
 
-    private function __construct(Message $dispatchedCommand, string $effectedAggregateId = null, Message ...$recordedEvents)
+    private function __construct(Message $dispatchedCommand, ?string $effectedAggregateId = null, Message ...$recordedEvents)
     {
         $this->dispatchedCommand = $dispatchedCommand;
         $this->effectedAggregateId = $effectedAggregateId;
diff --git a/src/Exception/MessageNotFound.php b/src/Exception/MessageNotFound.php
index b382111..f924283 100644
--- a/src/Exception/MessageNotFound.php
+++ b/src/Exception/MessageNotFound.php
@@ -20,7 +20,7 @@ public static function withMessageName(string $messageName): self
         return new self("Unknown message $messageName");
     }
 
-    public function __construct(string $message = "", Throwable $previous = null)
+    public function __construct(string $message = "", ?Throwable $previous = null)
     {
         parent::__construct($message, 404, $previous);
     }
diff --git a/src/Exception/RuntimeException.php b/src/Exception/RuntimeException.php
index fb843c1..0f0b224 100644
--- a/src/Exception/RuntimeException.php
+++ b/src/Exception/RuntimeException.php
@@ -15,7 +15,7 @@
 
 class RuntimeException extends \RuntimeException implements MessagingException
 {
-    public function __construct(string $message = "", Throwable $previous = null)
+    public function __construct(string $message = "", ?Throwable $previous = null)
     {
         parent::__construct($message, 500, $previous);
     }
diff --git a/src/MessageBag.php b/src/MessageBag.php
index e683664..6f0078a 100644
--- a/src/MessageBag.php
+++ b/src/MessageBag.php
@@ -77,7 +77,7 @@ final class MessageBag implements Message
      * @param \DateTimeImmutable|null $createdAt
      * @throws \Exception
      */
-    public function __construct(string $messageName, string $messageType, $message, $metadata = [], UuidInterface $messageId = null, \DateTimeImmutable $createdAt = null)
+    public function __construct(string $messageName, string $messageType, $message, $metadata = [], ?UuidInterface $messageId = null, ?\DateTimeImmutable $createdAt = null)
     {
         if (! \in_array($messageType, self::MSG_TYPES)) {
             throw new \InvalidArgumentException('Message type should be one of ' . \implode(', ', self::MSG_TYPES) . ". Got $messageType");