diff --git a/composer.json b/composer.json
index de5dd9e..38504ee 100644
--- a/composer.json
+++ b/composer.json
@@ -3,9 +3,10 @@
     "description": "Generates dummy mac addresses",
     "type": "library",
     "require": {
-      "php": "^7.2",
-      "ext-sodium": "*",
-      "ext-json": "*"
+        "php": ">=7.3",
+        "ext-json": "*",
+        "ext-sodium": "*",
+        "phpunit/phpunit": "^9.5"
     },
     "autoload": {
       "psr-4": {
@@ -14,7 +15,6 @@
     },
     "require-dev": {
         "symfony/console": "^4.1",
-        "phpunit/phpunit": "^7.4",
         "friendsofphp/php-cs-fixer": "^2.13",
         "squizlabs/php_codesniffer": "^3.3"
     },
diff --git a/phpunit.xml.dist b/phpunit.xml.dist
index 3db463a..799c7a6 100644
--- a/phpunit.xml.dist
+++ b/phpunit.xml.dist
@@ -1,24 +1,17 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <!-- https://phpunit.de/manual/current/en/appendixes.configuration.html -->
-<phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-         xsi:noNamespaceSchemaLocation="http://schema.phpunit.de/7.4/phpunit.xsd"
-         backupGlobals="false"
-         colors="true"
-         bootstrap="vendor/autoload.php"
->
-    <php>
-        <ini name="error_reporting" value="-1" />
-    </php>
-
-    <testsuites>
-        <testsuite name="Project Test Suite">
-            <directory>tests/</directory>
-        </testsuite>
-    </testsuites>
-
-    <filter>
-        <whitelist>
-            <directory>./src/</directory>
-        </whitelist>
-    </filter>
+<phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="https://schema.phpunit.de/9.3/phpunit.xsd" backupGlobals="false" colors="true" bootstrap="vendor/autoload.php">
+  <coverage>
+    <include>
+      <directory>./src/</directory>
+    </include>
+  </coverage>
+  <php>
+    <ini name="error_reporting" value="-1"/>
+  </php>
+  <testsuites>
+    <testsuite name="Project Test Suite">
+      <directory>tests/</directory>
+    </testsuite>
+  </testsuites>
 </phpunit>
diff --git a/tests/GenerateMacCommandTest.php b/tests/GenerateMacCommandTest.php
index 2655fb5..c61e43a 100644
--- a/tests/GenerateMacCommandTest.php
+++ b/tests/GenerateMacCommandTest.php
@@ -49,7 +49,7 @@ class GenerateMacCommandTest extends TestCase
     {
         $this->commandTester->execute([]);
         $display = $this->commandTester->getDisplay();
-        $this->assertContains('// Generated 1 mac addresses', $display);
+        $this->assertStringContainsString('// Generated 1 mac addresses', $display);
         $this->assertSame(0, $this->commandTester->getStatusCode());
         $this->expectException(\RuntimeException::class);
         $this->commandTester->execute(['--count' => -1]);
@@ -65,7 +65,7 @@ class GenerateMacCommandTest extends TestCase
     public function testPlain(): void
     {
         $this->commandTester->execute(['--output' => 'plain', '--count' => 1]);
-        $this->assertRegExp(self::REGEX, $this->commandTester->getDisplay());
+        $this->assertMatchesRegularExpression(self::REGEX, $this->commandTester->getDisplay());
         $this->assertSame(0, $this->commandTester->getStatusCode());
     }
 
diff --git a/tests/MacTest.php b/tests/MacTest.php
index da99e7b..a91abc3 100644
--- a/tests/MacTest.php
+++ b/tests/MacTest.php
@@ -36,10 +36,10 @@ class MacTest extends TestCase
         $this->assertCount(50, $macAddresses);
 
         foreach ($macAddresses as $address) {
-            $this->assertRegExp(self::REGEX, $address);
+            $this->assertMatchesRegularExpression(self::REGEX, $address);
         }
 
-        $this->assertRegExp(self::REGEX, $mac->getMacAddress());
+        $this->assertMatchesRegularExpression(self::REGEX, $mac->getMacAddress());
         $this->assertSame(Mac::SEPARATOR_COLON, $mac->getSeparator());
         $this->assertTrue($mac->getUnique());
     }
@@ -49,10 +49,10 @@ class MacTest extends TestCase
         $mac = new Mac(Mac::SEPARATOR_DASH);
 
         $this->assertSame(Mac::SEPARATOR_DASH, $mac->getSeparator());
-        $this->assertRegExp(self::REGEX, $mac->getMacAddress());
+        $this->assertMatchesRegularExpression(self::REGEX, $mac->getMacAddress());
         $mac->setSeparator(Mac::SEPARATOR_COLON);
         $this->assertSame(Mac::SEPARATOR_COLON, $mac->getSeparator());
-        $this->assertRegExp(self::REGEX, $mac->getMacAddress());
+        $this->assertMatchesRegularExpression(self::REGEX, $mac->getMacAddress());
         $this->assertNotFalse(strpos($mac->getMacAddress(), ':'));
     }