diff --git a/composer.json b/composer.json
index 186e544..b19ca28 100644
--- a/composer.json
+++ b/composer.json
@@ -19,7 +19,8 @@
         "phpunit/phpunit": "^9.5",
         "symfony/validator": "^5.4 || ^6.4 || ^7.0",
         "phpstan/phpstan": "^2.1",
-        "phpstan/phpstan-phpunit": "^2.0"
+        "phpstan/phpstan-phpunit": "^2.0",
+        "phpstan/phpstan-strict-rules": "^2.0"
     },
     "suggest": {
         "symfony/validator": "Add validation constraints",
diff --git a/phpstan.dist.neon b/phpstan.dist.neon
index 30a7c73..4590300 100644
--- a/phpstan.dist.neon
+++ b/phpstan.dist.neon
@@ -1,6 +1,7 @@
 includes:
     - vendor/phpstan/phpstan-phpunit/extension.neon
     - vendor/phpstan/phpstan-phpunit/rules.neon
+    - vendor/phpstan/phpstan-strict-rules/rules.neon
     - vendor/phpstan/phpstan/conf/bleedingEdge.neon
 
 parameters:
diff --git a/src/EmailChecker/Adapter/AggregatorAdapter.php b/src/EmailChecker/Adapter/AggregatorAdapter.php
new file mode 100644
index 0000000..f54372b
--- /dev/null
+++ b/src/EmailChecker/Adapter/AggregatorAdapter.php
@@ -0,0 +1,46 @@
+<?php
+
+/*
+ * This file is part of the EmailChecker package.
+ *
+ * (c) Matthieu Moquet <matthieu@moquet.net>
+ *
+ * This source file is subject to the MIT license that is bundled
+ * with this source code in the file LICENSE.
+ */
+
+namespace EmailChecker\Adapter;
+
+/**
+ * Combine data from other adapters.
+ *
+ * @author Matthieu Moquet <matthieu@moquet.net>
+ */
+class AggregatorAdapter implements AdapterInterface
+{
+    /**
+     * @var AdapterInterface[]
+     */
+    protected $adapters;
+
+    /**
+     * Build aggregator adapter with a list of adapters (order matters).
+     *
+     * @param AdapterInterface[] $adapters List of AdapterInterface objects
+     */
+    public function __construct(array $adapters)
+    {
+        $this->adapters = $adapters;
+    }
+
+    public function isThrowawayDomain($domain)
+    {
+        foreach ($this->adapters as $adapter) {
+            if ($adapter->isThrowawayDomain($domain)) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+}
diff --git a/src/EmailChecker/Adapter/AgregatorAdapter.php b/src/EmailChecker/Adapter/AgregatorAdapter.php
index 0b893e8..aadd2c2 100644
--- a/src/EmailChecker/Adapter/AgregatorAdapter.php
+++ b/src/EmailChecker/Adapter/AgregatorAdapter.php
@@ -15,32 +15,19 @@
  * Combine data from other adapters.
  *
  * @author Matthieu Moquet <matthieu@moquet.net>
+ *
+ * @deprecated Use \EmailChecker\Adapter\AggregatorAdapter instead.
  */
-class AgregatorAdapter implements AdapterInterface
+class AgregatorAdapter extends AggregatorAdapter
 {
-    /**
-     * @var AdapterInterface[]
-     */
-    protected $adapters;
-
-    /**
-     * Build aggregator adapter with a list of adapters (order matters).
-     *
-     * @param AdapterInterface[] $adapters List of AdapterInterface objects
-     */
     public function __construct(array $adapters)
     {
-        $this->adapters = $adapters;
-    }
-
-    public function isThrowawayDomain($domain)
-    {
-        foreach ($this->adapters as $adapter) {
-            if ($adapter->isThrowawayDomain($domain)) {
-                return true;
-            }
-        }
+        parent::__construct($adapters);
 
-        return false;
+        trigger_error(\sprintf(
+            'Since mattketmo/email-checker 2.5.0: Class "%s" is deprecated, use "%s" instead.',
+            self::class,
+            AggregatorAdapter::class,
+        ), \E_USER_DEPRECATED);
     }
 }
diff --git a/src/EmailChecker/Adapter/ArrayAdapter.php b/src/EmailChecker/Adapter/ArrayAdapter.php
index 56f7513..487d31c 100644
--- a/src/EmailChecker/Adapter/ArrayAdapter.php
+++ b/src/EmailChecker/Adapter/ArrayAdapter.php
@@ -33,6 +33,6 @@ public function __construct(array $domains)
 
     public function isThrowawayDomain($domain)
     {
-        return in_array($domain, $this->domains);
+        return in_array($domain, $this->domains, true);
     }
 }
diff --git a/src/EmailChecker/Adapter/BuiltInAdapter.php b/src/EmailChecker/Adapter/BuiltInAdapter.php
index 0a598cd..66a0984 100644
--- a/src/EmailChecker/Adapter/BuiltInAdapter.php
+++ b/src/EmailChecker/Adapter/BuiltInAdapter.php
@@ -32,7 +32,7 @@ class BuiltInAdapter implements AdapterInterface
 
     public function isThrowawayDomain($domain)
     {
-        return in_array($domain, $this->getDomains());
+        return in_array($domain, $this->getDomains(), true);
     }
 
     /**
diff --git a/src/EmailChecker/Adapter/FileAdapter.php b/src/EmailChecker/Adapter/FileAdapter.php
index f1bbeac..922ad9c 100644
--- a/src/EmailChecker/Adapter/FileAdapter.php
+++ b/src/EmailChecker/Adapter/FileAdapter.php
@@ -40,6 +40,6 @@ public function __construct($filename)
 
     public function isThrowawayDomain($domain)
     {
-        return in_array($domain, $this->domains);
+        return in_array($domain, $this->domains, true);
     }
 }
diff --git a/src/EmailChecker/Adapter/GaufretteAdapter.php b/src/EmailChecker/Adapter/GaufretteAdapter.php
index a7a4d21..cc1b330 100644
--- a/src/EmailChecker/Adapter/GaufretteAdapter.php
+++ b/src/EmailChecker/Adapter/GaufretteAdapter.php
@@ -33,6 +33,6 @@ public function __construct(File $file)
 
     public function isThrowawayDomain($domain)
     {
-        return in_array($domain, $this->domains);
+        return in_array($domain, $this->domains, true);
     }
 }
diff --git a/src/EmailChecker/Constraints/NotThrowawayEmailValidator.php b/src/EmailChecker/Constraints/NotThrowawayEmailValidator.php
index 50a7f2e..1ea2588 100644
--- a/src/EmailChecker/Constraints/NotThrowawayEmailValidator.php
+++ b/src/EmailChecker/Constraints/NotThrowawayEmailValidator.php
@@ -28,7 +28,7 @@ class NotThrowawayEmailValidator extends ConstraintValidator
 
     public function __construct(?EmailChecker $emailChecker = null)
     {
-        $this->emailChecker = $emailChecker ?: new EmailChecker();
+        $this->emailChecker = $emailChecker ?? new EmailChecker();
     }
 
     /**
diff --git a/src/EmailChecker/EmailChecker.php b/src/EmailChecker/EmailChecker.php
index 3acc4df..14e2ba3 100644
--- a/src/EmailChecker/EmailChecker.php
+++ b/src/EmailChecker/EmailChecker.php
@@ -49,7 +49,7 @@ public function isValid($email)
         }
 
         try {
-            list($local, $domain) = Utilities::parseEmailAddress($email);
+            [$local, $domain] = Utilities::parseEmailAddress($email);
         } catch (InvalidEmailException $e) {
             return false;
         }
diff --git a/src/EmailChecker/Utilities.php b/src/EmailChecker/Utilities.php
index 60d65a4..2eec987 100644
--- a/src/EmailChecker/Utilities.php
+++ b/src/EmailChecker/Utilities.php
@@ -34,7 +34,7 @@ public static function parseEmailAddress($email)
     {
         $pattern = sprintf('/^(?<local>%s)@(?<domain>%s)$/iD', self::EMAIL_REGEX_LOCAL, self::EMAIL_REGEX_DOMAIN);
 
-        if (!preg_match($pattern, $email, $parts)) {
+        if (1 !== preg_match($pattern, $email, $parts)) {
             throw new InvalidEmailException(sprintf('"%s" is not a valid email', $email));
         }
 
@@ -60,7 +60,7 @@ public static function parseLines($content)
         // Remove empty lines and comments
         return array_filter(
             $lines,
-            static fn (string $line): bool => 0 !== strlen($line) && '#' !== $line[0],
+            static fn (string $line): bool => $line !== '' && '#' !== $line[0],
         );
     }
 }
diff --git a/tests/EmailChecker/Tests/Adpater/AggregatorAdapterTest.php b/tests/EmailChecker/Tests/Adpater/AggregatorAdapterTest.php
new file mode 100644
index 0000000..950bdac
--- /dev/null
+++ b/tests/EmailChecker/Tests/Adpater/AggregatorAdapterTest.php
@@ -0,0 +1,66 @@
+<?php
+
+/*
+ * This file is part of the EmailChecker package.
+ *
+ * (c) Matthieu Moquet <matthieu@moquet.net>
+ *
+ * This source file is subject to the MIT license that is bundled
+ * with this source code in the file LICENSE.
+ */
+
+namespace EmailChecker\Tests\Adpater;
+
+use EmailChecker\Adapter\AdapterInterface;
+use EmailChecker\Adapter\AggregatorAdapter;
+use EmailChecker\Tests\TestCase;
+
+final class AggregatorAdapterTest extends TestCase
+{
+    public function testAllValid(): void
+    {
+        $adapter1 = $this->getAdapterMock(false);
+        $adapter2 = $this->getAdapterMock(false);
+
+        $adapter = new AggregatorAdapter([$adapter1, $adapter2]);
+
+        self::assertFalse($adapter->isThrowawayDomain('example.org'));
+    }
+
+    public function testFirstInvalid(): void
+    {
+        $adapter1 = $this->getAdapterMock(true);
+        $adapter2 = $this->getAdapterMock(false);
+
+        $adapter = new AggregatorAdapter([$adapter1, $adapter2]);
+
+        self::assertTrue($adapter->isThrowawayDomain('example.org'));
+    }
+
+    public function testSecondInvalid(): void
+    {
+        $adapter1 = $this->getAdapterMock(false);
+        $adapter2 = $this->getAdapterMock(true);
+
+        $adapter = new AggregatorAdapter([$adapter1, $adapter2]);
+
+        self::assertTrue($adapter->isThrowawayDomain('example.org'));
+    }
+
+    /**
+     * Build a mock of adapter interface.
+     *
+     * @param bool $isThrowawayDomain The value returned by the isThrowawayDomain method
+     *
+     * @return AdapterInterface The mock adapter
+     */
+    private function getAdapterMock(bool $isThrowawayDomain): AdapterInterface
+    {
+        $adapter = $this->createStub(AdapterInterface::class);
+        $adapter
+            ->method('isThrowawayDomain')
+            ->willReturn($isThrowawayDomain);
+
+        return $adapter;
+    }
+}
diff --git a/tests/EmailChecker/Tests/Adpater/AgregatorAdapterTest.php b/tests/EmailChecker/Tests/Adpater/AgregatorAdapterTest.php
deleted file mode 100644
index 60bdda1..0000000
--- a/tests/EmailChecker/Tests/Adpater/AgregatorAdapterTest.php
+++ /dev/null
@@ -1,66 +0,0 @@
-<?php
-
-/*
- * This file is part of the EmailChecker package.
- *
- * (c) Matthieu Moquet <matthieu@moquet.net>
- *
- * This source file is subject to the MIT license that is bundled
- * with this source code in the file LICENSE.
- */
-
-namespace EmailChecker\Tests\Adpater;
-
-use EmailChecker\Adapter\AdapterInterface;
-use EmailChecker\Adapter\AgregatorAdapter;
-use EmailChecker\Tests\TestCase;
-
-final class AgregatorAdapterTest extends TestCase
-{
-    public function testAllValid(): void
-    {
-        $adapter1 = $this->getAdapterMock(false, 'once');
-        $adapter2 = $this->getAdapterMock(false, 'once');
-
-        $adapter = new AgregatorAdapter([$adapter1, $adapter2]);
-
-        $this->assertFalse($adapter->isThrowawayDomain('example.org'));
-    }
-
-    public function testFirstInvalid(): void
-    {
-        $adapter1 = $this->getAdapterMock(true, 'once');
-        $adapter2 = $this->getAdapterMock(false, 'never');
-
-        $adapter = new AgregatorAdapter([$adapter1, $adapter2]);
-
-        $this->assertTrue($adapter->isThrowawayDomain('example.org'));
-    }
-
-    public function testSecondInvalid(): void
-    {
-        $adapter1 = $this->getAdapterMock(false, 'once');
-        $adapter2 = $this->getAdapterMock(true, 'once');
-
-        $adapter = new AgregatorAdapter([$adapter1, $adapter2]);
-
-        $this->assertTrue($adapter->isThrowawayDomain('example.org'));
-    }
-
-    /**
-     * Build a mock of adapter interface.
-     *
-     * @param bool $isThrowawayDomain The value returned by the isThrowawayDomain method
-     *
-     * @return AdapterInterface The mock adapter
-     */
-    protected function getAdapterMock(bool $isThrowawayDomain, string $call = 'any'): AdapterInterface
-    {
-        $adapter = $this->createMock(AdapterInterface::class);
-        $adapter->expects($this->$call())
-            ->method('isThrowawayDomain')
-            ->will($this->returnValue($isThrowawayDomain));
-
-        return $adapter;
-    }
-}
diff --git a/tests/EmailChecker/Tests/Adpater/ArrayAdapterTest.php b/tests/EmailChecker/Tests/Adpater/ArrayAdapterTest.php
index 52908a3..6f3a867 100644
--- a/tests/EmailChecker/Tests/Adpater/ArrayAdapterTest.php
+++ b/tests/EmailChecker/Tests/Adpater/ArrayAdapterTest.php
@@ -35,7 +35,7 @@ protected function setUp(): void
      */
     public function testThrowawayDomains(string $domain): void
     {
-        $this->assertTrue($this->adapter->isThrowawayDomain($domain));
+        self::assertTrue($this->adapter->isThrowawayDomain($domain));
     }
 
     /**
@@ -43,7 +43,7 @@ public function testThrowawayDomains(string $domain): void
      */
     public function testNotThrowawayDomains(string $domain): void
     {
-        $this->assertFalse($this->adapter->isThrowawayDomain($domain));
+        self::assertFalse($this->adapter->isThrowawayDomain($domain));
     }
 
     public static function throwawayDomains(): iterable
diff --git a/tests/EmailChecker/Tests/Adpater/BuiltInAdapterTest.php b/tests/EmailChecker/Tests/Adpater/BuiltInAdapterTest.php
index 6b9152c..e91e977 100644
--- a/tests/EmailChecker/Tests/Adpater/BuiltInAdapterTest.php
+++ b/tests/EmailChecker/Tests/Adpater/BuiltInAdapterTest.php
@@ -30,7 +30,7 @@ protected function setUp(): void
      */
     public function testThrowawayDomains(string $domain): void
     {
-        $this->assertTrue($this->adapter->isThrowawayDomain($domain));
+        self::assertTrue($this->adapter->isThrowawayDomain($domain));
     }
 
     public static function throwawayDomains(): iterable
diff --git a/tests/EmailChecker/Tests/Adpater/FileAdapterTest.php b/tests/EmailChecker/Tests/Adpater/FileAdapterTest.php
index fa683b3..c2edc75 100644
--- a/tests/EmailChecker/Tests/Adpater/FileAdapterTest.php
+++ b/tests/EmailChecker/Tests/Adpater/FileAdapterTest.php
@@ -30,7 +30,7 @@ protected function setUp(): void
      */
     public function testThrowawayDomains(string $domain): void
     {
-        $this->assertTrue($this->adapter->isThrowawayDomain($domain));
+        self::assertTrue($this->adapter->isThrowawayDomain($domain));
     }
 
     /**
@@ -38,7 +38,7 @@ public function testThrowawayDomains(string $domain): void
      */
     public function testNotThrowawayDomains(string $domain): void
     {
-        $this->assertFalse($this->adapter->isThrowawayDomain($domain));
+        self::assertFalse($this->adapter->isThrowawayDomain($domain));
     }
 
     public static function throwawayDomains(): iterable
diff --git a/tests/EmailChecker/Tests/Adpater/GaufretteAdapterTest.php b/tests/EmailChecker/Tests/Adpater/GaufretteAdapterTest.php
index 13b30eb..40800f8 100644
--- a/tests/EmailChecker/Tests/Adpater/GaufretteAdapterTest.php
+++ b/tests/EmailChecker/Tests/Adpater/GaufretteAdapterTest.php
@@ -36,7 +36,7 @@ protected function setUp(): void
      */
     public function testThrowawayDomains(string $domain): void
     {
-        $this->assertTrue($this->adapter->isThrowawayDomain($domain));
+        self::assertTrue($this->adapter->isThrowawayDomain($domain));
     }
 
     /**
@@ -44,7 +44,7 @@ public function testThrowawayDomains(string $domain): void
      */
     public function testNotThrowawayDomains(string $domain): void
     {
-        $this->assertFalse($this->adapter->isThrowawayDomain($domain));
+        self::assertFalse($this->adapter->isThrowawayDomain($domain));
     }
 
     public static function throwawayDomains(): iterable
diff --git a/tests/EmailChecker/Tests/Constraint/NotThrowawayEmailValidatorTest.php b/tests/EmailChecker/Tests/Constraint/NotThrowawayEmailValidatorTest.php
index 7c33250..ad9f962 100644
--- a/tests/EmailChecker/Tests/Constraint/NotThrowawayEmailValidatorTest.php
+++ b/tests/EmailChecker/Tests/Constraint/NotThrowawayEmailValidatorTest.php
@@ -35,7 +35,7 @@ protected function setUp(): void
 
     public function testNullIsValid(): void
     {
-        $this->context->expects($this->never())
+        $this->context->expects(self::never())
             ->method('addViolation');
 
         $this->validator->validate(null, new NotThrowawayEmail());
@@ -43,7 +43,7 @@ public function testNullIsValid(): void
 
     public function testEmptyStringIsValid(): void
     {
-        $this->context->expects($this->never())
+        $this->context->expects(self::never())
             ->method('addViolation');
 
         $this->validator->validate('', new NotThrowawayEmail());
@@ -61,7 +61,7 @@ public function testExpectsStringCompatibleType(): void
      */
     public function testValidEmails(string $email): void
     {
-        $this->context->expects($this->never())
+        $this->context->expects(self::never())
             ->method('addViolation');
 
         $this->validator->validate($email, new NotThrowawayEmail());
@@ -84,7 +84,7 @@ public function testInvalidEmails(string $email): void
             'message' => 'myMessage',
         ]);
 
-        $this->context->expects($this->once())
+        $this->context->expects(self::once())
             ->method('addViolation')
             ->with('myMessage');
 
diff --git a/tests/EmailChecker/Tests/EmailCheckerTest.php b/tests/EmailChecker/Tests/EmailCheckerTest.php
index f9b3ab1..78ce8e6 100644
--- a/tests/EmailChecker/Tests/EmailCheckerTest.php
+++ b/tests/EmailChecker/Tests/EmailCheckerTest.php
@@ -25,7 +25,7 @@ public function testEmailIsValid(): void
 
         $checker = new EmailChecker($adapter);
 
-        $this->assertTrue($checker->isValid('foo@bar.org'));
+        self::assertTrue($checker->isValid('foo@bar.org'));
     }
 
     public function testEmailIsNotValid(): void
@@ -37,7 +37,7 @@ public function testEmailIsNotValid(): void
 
         $checker = new EmailChecker($adapter);
 
-        $this->assertFalse($checker->isValid('foo@bar.org'));
+        self::assertFalse($checker->isValid('foo@bar.org'));
     }
 
     public function testMalformattedEmail(): void
@@ -45,6 +45,6 @@ public function testMalformattedEmail(): void
         $adapter = $this->createMock(AdapterInterface::class);
         $checker = new EmailChecker($adapter);
 
-        $this->assertFalse($checker->isValid('foo[at]bar.org'));
+        self::assertFalse($checker->isValid('foo[at]bar.org'));
     }
 }
diff --git a/tests/EmailChecker/Tests/ThrowawayDomainsTest.php b/tests/EmailChecker/Tests/ThrowawayDomainsTest.php
index 12ee8cc..12ec810 100644
--- a/tests/EmailChecker/Tests/ThrowawayDomainsTest.php
+++ b/tests/EmailChecker/Tests/ThrowawayDomainsTest.php
@@ -19,6 +19,6 @@ public function testIsInstanciable(): void
     {
         $domains = new ThrowawayDomains();
 
-        $this->assertGreaterThan(0, count($domains));
+        self::assertGreaterThan(0, count($domains));
     }
 }
diff --git a/tests/EmailChecker/Tests/UtilitiesTest.php b/tests/EmailChecker/Tests/UtilitiesTest.php
index 331d5be..cf98b8b 100644
--- a/tests/EmailChecker/Tests/UtilitiesTest.php
+++ b/tests/EmailChecker/Tests/UtilitiesTest.php
@@ -21,9 +21,9 @@ final class UtilitiesTest extends TestCase
      */
     public function testParseValidEmail(string $email, string $exceptedLocal, string $exceptedDomain): void
     {
-        list($local, $domain) = Utilities::parseEmailAddress($email);
+        [$local, $domain] = Utilities::parseEmailAddress($email);
 
-        $this->assertEquals([$exceptedLocal, $exceptedDomain], [$local, $domain]);
+        self::assertEquals([$exceptedLocal, $exceptedDomain], [$local, $domain]);
     }
 
     /**
@@ -33,7 +33,7 @@ public function testParseInvalidEmail(string $email): void
     {
         try {
             Utilities::parseEmailAddress($email);
-            $this->fail(sprintf('"%s" should not be a valid email', $email));
+            self::fail(sprintf('"%s" should not be a valid email', $email));
         } catch (InvalidEmailException $e) {
             return;
         }
@@ -65,7 +65,7 @@ public function testParseLines(): void
 Actual:
 %s
 MSG;
-        $this->assertEmpty($diffs, sprintf($message, print_r($expectedLines, true), print_r($parsedContent, true)));
+        self::assertEmpty($diffs, sprintf($message, print_r($expectedLines, true), print_r($parsedContent, true)));
     }
 
     public static function validEmails(): iterable