diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index c7d521d..3f0b631 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -14,7 +14,7 @@ jobs:
     strategy:
       fail-fast: true
       matrix:
-        php: [8.2, 8.3]
+        php: [8.2, 8.3, 8.4]
 
     steps:
     - name: Checkout Code
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 8bed379..83a2a79 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,10 @@ All notable changes to this project will be documented in this file. This projec
 
 ## Unreleased
 
+### Fixed
+
+- Remove deprecation notices on PHP 8.4.
+
 ## [3.0.0] - 2024-03-12
 
 ### Changed
diff --git a/phpunit.xml b/phpunit.xml
index c2d37a1..215e292 100644
--- a/phpunit.xml
+++ b/phpunit.xml
@@ -13,6 +13,7 @@
          failOnWarning="true"
          failOnDeprecation="true"
          failOnNotice="true"
+         displayDetailsOnTestsThatTriggerDeprecations="true"
 >
     <coverage/>
     <testsuites>
diff --git a/src/TestResponse.php b/src/TestResponse.php
index af8af90..a93e592 100644
--- a/src/TestResponse.php
+++ b/src/TestResponse.php
@@ -41,7 +41,7 @@ public static function cast($response): self
      * @param Response $response
      * @param string|null $expectedType
      */
-    public function __construct($response, string $expectedType = null)
+    public function __construct($response, ?string $expectedType = null)
     {
         parent::__construct($response);
 
@@ -116,7 +116,7 @@ public function getLocation(): ?string
      * @param string|null $pointer
      * @return Document|mixed
      */
-    public function jsonApi(string $pointer = null)
+    public function jsonApi(?string $pointer = null)
     {
         $document = $this->getDocument();