diff --git a/src/polyfill.php b/src/polyfill.php
index 480310d4..2d216c7b 100644
--- a/src/polyfill.php
+++ b/src/polyfill.php
@@ -42,77 +42,3 @@ class NamedArgumentConstructor
         }
     }
 }
-
-namespace {
-    use JetBrains\PhpStorm\ExpectedValues;
-
-    if (!\class_exists(Attribute::class, false)) {
-        #[Attribute(Attribute::TARGET_CLASS)]
-        final class Attribute
-        {
-            /**
-             * Marks that attribute declaration is allowed only in classes.
-             *
-             * @var Attribute::TARGET_*
-             */
-            public const TARGET_CLASS = 0b00000001;
-
-            /**
-             * Marks that attribute declaration is allowed only in functions.
-             *
-             * @var Attribute::TARGET_*
-             */
-            public const TARGET_FUNCTION = 0b00000010;
-
-            /**
-             * Marks that attribute declaration is allowed only in class methods.
-             *
-             * @var Attribute::TARGET_*
-             */
-            public const TARGET_METHOD = 0b00000100;
-
-            /**
-             * Marks that attribute declaration is allowed only in class properties.
-             *
-             * @var Attribute::TARGET_*
-             */
-            public const TARGET_PROPERTY = 0b00001000;
-
-            /**
-             * Marks that attribute declaration is allowed only in class constants.
-             *
-             * @var Attribute::TARGET_*
-             */
-            public const TARGET_CLASS_CONSTANT = 0b00010000;
-
-            /**
-             * Marks that attribute declaration is allowed only in function or method parameters.
-             *
-             * @var Attribute::TARGET_*
-             */
-            public const TARGET_PARAMETER = 0b00010000;
-
-            /**
-             * Marks that attribute declaration is allowed anywhere.
-             *
-             * @var int-mask-of<Attribute::TARGET_*>
-             */
-            public const TARGET_ALL = self::TARGET_CLASS
-                                    | self::TARGET_FUNCTION
-                                    | self::TARGET_METHOD
-                                    | self::TARGET_PROPERTY
-                                    | self::TARGET_PARAMETER
-            ;
-
-            /**
-             * Notes that an attribute declaration in the same place is allowed multiple times.
-             */
-            public const IS_REPEATABLE = 0b00100000;
-
-            /**
-             * @var int-mask-of<Attribute::TARGET_*>
-             */
-            public $flags;
-        }
-    }
-}