diff --git a/bin/cs b/bin/cs
index e8757cc..9531563 100755
--- a/bin/cs
+++ b/bin/cs
@@ -6,7 +6,7 @@ declare(strict_types = 1);
 passthru(
 	escapeshellarg(__DIR__ . '/../vendor/bin/phpcs')
 	. ' ' . escapeshellarg('--standard=' . __DIR__ . '/../tools/cs/ruleset.xml')
-	. ' --parallel=1 --extensions=php,phpt --encoding=utf-8 --tab-width=4 --colors -sp'
+	. ' --parallel=1 --extensions=php,phpt --encoding=utf-8 --tab-width=4 --colors -sp --runtime-set php_version 080100'
 	. ' '
 	. __DIR__ . '/../src'
 	. ' '
diff --git a/src/CountryCode.php b/src/CountryCode.php
index 6e9dffe..6dfefcd 100644
--- a/src/CountryCode.php
+++ b/src/CountryCode.php
@@ -10,6 +10,7 @@
  * ISO-3166-1 Alpha 2 country code enum
  *
  * @see https://en.wikipedia.org/wiki/ISO_3166-1_alpha-2
+ * @extends \SmartEmailing\Types\Enum<string>
  */
 final class CountryCode extends Enum implements ToStringInterface
 {
diff --git a/src/CurrencyCode.php b/src/CurrencyCode.php
index 77170f2..59cfd67 100644
--- a/src/CurrencyCode.php
+++ b/src/CurrencyCode.php
@@ -8,6 +8,8 @@
 
 /**
  * ISO-4217 three-letter ("Alpha-3")
+ *
+ * @extends \SmartEmailing\Types\Enum<string>
  */
 final class CurrencyCode extends Enum implements ToStringInterface
 {
diff --git a/src/Enum.php b/src/Enum.php
index 75ceec2..892e088 100644
--- a/src/Enum.php
+++ b/src/Enum.php
@@ -8,11 +8,14 @@
 use ReflectionClass;
 use ReflectionClassConstant;
 
+/**
+ * @template T
+ */
 abstract class Enum
 {
 
 	/**
-	 * @var mixed
+	 * @var T
 	 */
 	private $value;
 
@@ -22,7 +25,7 @@ abstract class Enum
 	private static array $instances = [];
 
 	/**
-	 * @var array<string, mixed>
+	 * @var array<string, array<T>>
 	 */
 	private static array $availableValues = [];
 
@@ -52,11 +55,17 @@ final public static function get(
 		return self::$instances[$index];
 	}
 
-	public function getValue(): mixed
+	/**
+	 * @return T
+	 */
+	public function getValue()
 	{
 		return $this->value;
 	}
 
+	/**
+	 * @param self<T> $that
+	 */
 	public function equals(
 		self $that
 	): bool
@@ -93,7 +102,7 @@ public static function checkValue(
 	}
 
 	/**
-	 * @return array<mixed>
+	 * @return array<T>
 	 */
 	public static function getAvailableValues(): array
 	{
@@ -130,6 +139,9 @@ public static function isValidValue(
 		return \in_array($value, self::getAvailableValues(), true);
 	}
 
+	/**
+	 * @param self<T> $that
+	 */
 	protected function checkSameEnum(
 		self $that
 	): void
@@ -140,7 +152,7 @@ protected function checkSameEnum(
 	}
 
 	/**
-	 * @param array<mixed> $availableValues
+	 * @param array<T> $availableValues
 	 */
 	protected static function checkAvailableValues(
 		array $availableValues
@@ -218,7 +230,7 @@ private static function getValueIndex(
 	}
 
 	/**
-	 * @return array<string, mixed>
+	 * @return array<string, T>
 	 */
 	private static function getEnumConstants(): array
 	{
diff --git a/src/FieldOfApplication.php b/src/FieldOfApplication.php
index 849687e..4c77b7f 100644
--- a/src/FieldOfApplication.php
+++ b/src/FieldOfApplication.php
@@ -6,6 +6,9 @@
 
 use SmartEmailing\Types\ExtractableTraits\EnumExtractableTrait;
 
+/**
+ * @extends \SmartEmailing\Types\Enum<string>
+ */
 final class FieldOfApplication extends Enum
 {
 
diff --git a/src/Guid.php b/src/Guid.php
index fdbf0aa..640e989 100644
--- a/src/Guid.php
+++ b/src/Guid.php
@@ -39,7 +39,7 @@ public static function fromHex32(
 		return self::from(
 			\sprintf(
 				'%s%s-%s-%s-%s-%s%s%s',
-				...$parts
+				...$parts // phpcs:disable SlevomatCodingStandard.PHP.OptimizedFunctionsWithoutUnpacking.UnpackingUsed
 			)
 		);
 	}
diff --git a/src/HttpMethod.php b/src/HttpMethod.php
index 4802787..47f8133 100644
--- a/src/HttpMethod.php
+++ b/src/HttpMethod.php
@@ -4,16 +4,16 @@
 
 namespace SmartEmailing\Types;
 
-use SmartEmailing\Types\Comparable\ComparableInterface;
-use SmartEmailing\Types\Comparable\StringComparableTrait;
 use SmartEmailing\Types\ExtractableTraits\EnumExtractableTrait;
 
-final class HttpMethod extends Enum implements ToStringInterface, ComparableInterface
+/**
+ * @extends \SmartEmailing\Types\Enum<string>
+ */
+final class HttpMethod extends Enum implements ToStringInterface
 {
 
 	use EnumExtractableTrait;
 	use ToStringTrait;
-	use StringComparableTrait;
 
 	public const GET = 'GET';
 
diff --git a/src/LawfulBasisForProcessing.php b/src/LawfulBasisForProcessing.php
index 34337b7..22f416a 100644
--- a/src/LawfulBasisForProcessing.php
+++ b/src/LawfulBasisForProcessing.php
@@ -11,6 +11,7 @@
  *
  * @package SmartEmailing\Types
  * @see https://ico.org.uk/for-organisations/guide-to-the-general-data-protection-regulation-gdpr/lawful-basis-for-processing/
+ * @extends \SmartEmailing\Types\Enum<string>
  */
 final class LawfulBasisForProcessing extends Enum
 {
diff --git a/src/Relation.php b/src/Relation.php
index bf9396d..199c687 100644
--- a/src/Relation.php
+++ b/src/Relation.php
@@ -6,6 +6,9 @@
 
 use SmartEmailing\Types\ExtractableTraits\EnumExtractableTrait;
 
+/**
+ * @extends \SmartEmailing\Types\Enum<string>
+ */
 final class Relation extends Enum
 {
 
diff --git a/src/TimeUnit.php b/src/TimeUnit.php
index f1e732f..927be3c 100644
--- a/src/TimeUnit.php
+++ b/src/TimeUnit.php
@@ -6,6 +6,9 @@
 
 use SmartEmailing\Types\ExtractableTraits\EnumExtractableTrait;
 
+/**
+ * @extends \SmartEmailing\Types\Enum<string>
+ */
 final class TimeUnit extends Enum implements ToStringInterface
 {
 
diff --git a/tests/EnumTest.phpt b/tests/EnumTest.phpt
index 3894921..4a30583 100644
--- a/tests/EnumTest.phpt
+++ b/tests/EnumTest.phpt
@@ -10,6 +10,9 @@ use Tester\TestCase;
 
 require __DIR__ . '/bootstrap.php';
 
+/**
+ * @extends \SmartEmailing\Types\Enum<string>
+ */
 final class SimpleEnum extends Enum
 {