diff --git a/src/Recorders/DumpRecorder/HtmlDumper.php b/src/Recorders/DumpRecorder/HtmlDumper.php
index ebf1839..4f7667e 100644
--- a/src/Recorders/DumpRecorder/HtmlDumper.php
+++ b/src/Recorders/DumpRecorder/HtmlDumper.php
@@ -8,7 +8,7 @@
 
 class HtmlDumper extends BaseHtmlDumper
 {
-    public function __construct($output = null, string $charset = null, int $flags = 0)
+    public function __construct($output = null, ?string $charset = null, int $flags = 0)
     {
         parent::__construct($output, $charset, $flags);
 
diff --git a/tests/TestClasses/FakeTime.php b/tests/TestClasses/FakeTime.php
index 0569a5f..30eba3c 100644
--- a/tests/TestClasses/FakeTime.php
+++ b/tests/TestClasses/FakeTime.php
@@ -9,7 +9,7 @@ class FakeTime implements Time
 {
     protected DateTimeImmutable $dateTime;
 
-    public function __construct(string $dateTime = null, $format = 'Y-m-d H:i:s')
+    public function __construct(?string $dateTime = null, $format = 'Y-m-d H:i:s')
     {
         if (! is_null($dateTime)) {
             $this->setCurrentTime($dateTime, $format);