diff --git a/composer.json b/composer.json
index 8b148fd..e00eb4a 100644
--- a/composer.json
+++ b/composer.json
@@ -10,12 +10,13 @@
         }
     ],
     "require": {
-        "php": ">=7.1.0",
+        "php": "^7.3 || ^8.0",
         "silverstripe/admin": "^1.0"
     },
     "require-dev": {
-        "sminnee/phpunit": "^5.7",
-        "squizlabs/php_codesniffer": "^3.0"
+        "phpunit/phpunit": "^9.5",
+        "silverstripe/framework": "^4.10",
+        "squizlabs/php_codesniffer": "^3"
     },
     "autoload": {
         "psr-4": {
diff --git a/phpunit.xml.dist b/phpunit.xml.dist
index f148411..69df172 100644
--- a/phpunit.xml.dist
+++ b/phpunit.xml.dist
@@ -1,7 +1,9 @@
 <phpunit bootstrap="vendor/silverstripe/cms/tests/bootstrap.php" colors="true">
-    <testsuite name="Default">
-        <directory>tests</directory>
-    </testsuite>
+    <testsuites>
+        <testsuite name="Default">
+            <directory>tests</directory>
+        </testsuite>
+    </testsuites>
 
     <filter>
         <whitelist addUncoveredFilesFromWhitelist="true">
diff --git a/tests/php/Control/SudoModeControllerTest.php b/tests/php/Control/SudoModeControllerTest.php
index 6609ed1..970a698 100644
--- a/tests/php/Control/SudoModeControllerTest.php
+++ b/tests/php/Control/SudoModeControllerTest.php
@@ -23,7 +23,7 @@ class SudoModeControllerTest extends FunctionalTest
      */
     private $securityTokenEnabled;
 
-    protected function setUp()
+    protected function setUp(): void
     {
         parent::setUp();
 
@@ -37,7 +37,7 @@ protected function setUp()
         $member->changePassword('0p3nS3samE!');
     }
 
-    protected function tearDown()
+    protected function tearDown(): void
     {
         if ($this->securityTokenEnabled) {
             SecurityToken::enable();
diff --git a/tests/php/Extension/SudoModeOnLoginExtensionTest.php b/tests/php/Extension/SudoModeOnLoginExtensionTest.php
index 8d2cdc2..da81a42 100644
--- a/tests/php/Extension/SudoModeOnLoginExtensionTest.php
+++ b/tests/php/Extension/SudoModeOnLoginExtensionTest.php
@@ -19,7 +19,7 @@ class SudoModeOnLoginExtensionTest extends FunctionalTest
         ],
     ];
 
-    protected function setUp()
+    protected function setUp(): void
     {
         parent::setUp();
 
diff --git a/tests/php/Service/SudoModeServiceTest.php b/tests/php/Service/SudoModeServiceTest.php
index 5e048d5..a0836c3 100644
--- a/tests/php/Service/SudoModeServiceTest.php
+++ b/tests/php/Service/SudoModeServiceTest.php
@@ -21,7 +21,7 @@ class SudoModeServiceTest extends SapphireTest
      */
     private $service;
 
-    protected function setUp()
+    protected function setUp(): void
     {
         parent::setUp();