diff --git a/composer.json b/composer.json
index 851b764..50a36c9 100755
--- a/composer.json
+++ b/composer.json
@@ -26,7 +26,7 @@
         "silverstripe/vendor-plugin": "^2"
     },
     "require-dev": {
-        "phpunit/phpunit": "^9.6",
+        "phpunit/phpunit": "^11.3",
         "squizlabs/php_codesniffer": "^3.7",
         "silverstripe/standards": "^1",
         "phpstan/extension-installer": "^1.3"
diff --git a/tests/ErrorPageTest.php b/tests/ErrorPageTest.php
index aa61b7b..8cedb4b 100644
--- a/tests/ErrorPageTest.php
+++ b/tests/ErrorPageTest.php
@@ -247,7 +247,7 @@ public function testErrorMessageAppended($env, $shouldShowInDev)
     /**
      * @return array
      */
-    public function provideErrorMessageEnv()
+    public static function provideErrorMessageEnv()
     {
         return [
             ['dev', true],