diff --git a/src/Exception.php b/src/Exception.php
index a53e211..36515f4 100644
--- a/src/Exception.php
+++ b/src/Exception.php
@@ -14,7 +14,7 @@ class Exception extends RuntimeException
     /**
      * @param array<string|int> $args
      */
-    public function __construct(string $message, array $args = [], Throwable $previous = null)
+    public function __construct(string $message, array $args = [], ?Throwable $previous = null)
     {
         $message = $args ? vsprintf($message, $args) : $message;
 
diff --git a/src/Hydration/HydrationException.php b/src/Hydration/HydrationException.php
index 78302bf..a89334b 100644
--- a/src/Hydration/HydrationException.php
+++ b/src/Hydration/HydrationException.php
@@ -12,7 +12,7 @@ class HydrationException extends Exception
     /**
      * @param array<string|int> $args
      */
-    public function __construct(string $message, array $args = [], Throwable $previous = null)
+    public function __construct(string $message, array $args = [], ?Throwable $previous = null)
     {
         parent::__construct("FromArray Error: {$message}", $args, $previous);
     }
diff --git a/src/Kit.php b/src/Kit.php
index 36fa174..43a4659 100644
--- a/src/Kit.php
+++ b/src/Kit.php
@@ -120,7 +120,7 @@ public static function divider(?string $blockId = null): Blocks\Divider
     }
 
     public static function file(
-        string $externalId = null,
+        ?string $externalId = null,
         ?string $source = 'remote',
         ?string $blockId = null,
     ): Blocks\File {