diff --git a/components/asset.rst b/components/asset.rst
index 2c95a35589e..8ffdbd7e41d 100644
--- a/components/asset.rst
+++ b/components/asset.rst
@@ -203,7 +203,7 @@ every day::
 
     class DateVersionStrategy implements VersionStrategyInterface
     {
-        private $version;
+        private \DateTimeInterface $version;
 
         public function __construct()
         {
diff --git a/components/dependency_injection.rst b/components/dependency_injection.rst
index 6d8672feeef..45ecc6dc194 100644
--- a/components/dependency_injection.rst
+++ b/components/dependency_injection.rst
@@ -31,7 +31,7 @@ you want to make available as a service::
 
     class Mailer
     {
-        private $transport;
+        private string $transport;
 
         public function __construct()
         {
@@ -55,7 +55,7 @@ so this is passed into the constructor::
     class Mailer
     {
         public function __construct(
-            private $transport,
+            private string $transport,
         ) {
         }
 
@@ -124,7 +124,7 @@ it was only optional then you could use setter injection instead::
 
     class NewsletterManager
     {
-        private $mailer;
+        private \Mailer $mailer;
 
         public function setMailer(\Mailer $mailer)
         {
diff --git a/components/property_access.rst b/components/property_access.rst
index 3364b667a5c..bf1453d17ee 100644
--- a/components/property_access.rst
+++ b/components/property_access.rst
@@ -118,7 +118,7 @@ it with ``get``. So the actual method becomes ``getFirstName()``::
     // ...
     class Person
     {
-        private $firstName = 'Wouter';
+        private string $firstName = 'Wouter';
 
         public function getFirstName()
         {
@@ -140,8 +140,8 @@ getters, this means that you can do something like this::
     // ...
     class Person
     {
-        private $author = true;
-        private $children = [];
+        private bool $author = true;
+        private array $children = [];
 
         public function isAuthor()
         {
@@ -233,7 +233,7 @@ The ``getValue()`` method can also use the magic ``__get()`` method::
     // ...
     class Person
     {
-        private $children = [
+        private array $children = [
             'Wouter' => [...],
         ];
 
@@ -263,7 +263,7 @@ enable this feature by using :class:`Symfony\\Component\\PropertyAccess\\Propert
     // ...
     class Person
     {
-        private $children = [
+        private array $children = [
             'wouter' => [...],
         ];
 
@@ -362,7 +362,7 @@ see `Enable other Features`_::
     // ...
     class Person
     {
-        private $children = [];
+        private array $children = [];
 
         public function __call($name, $args)
         {
@@ -405,7 +405,7 @@ properties through *adder* and *remover* methods::
         /**
          * @var string[]
          */
-        private $children = [];
+        private array $children = [];
 
         public function getChildren(): array
         {
diff --git a/components/property_info.rst b/components/property_info.rst
index 6aa2210a728..37c425d85df 100644
--- a/components/property_info.rst
+++ b/components/property_info.rst
@@ -431,7 +431,7 @@ information from annotations of properties and methods, such as ``@var``,
          * @param string $bar
          */
         public function __construct(
-            private $bar,
+            private string $bar,
         ) {
         }
     }
diff --git a/components/runtime.rst b/components/runtime.rst
index 956e731c5ab..8f07968e5ca 100644
--- a/components/runtime.rst
+++ b/components/runtime.rst
@@ -440,7 +440,7 @@ always using this ``ReactPHPRunner``::
 
     class ReactPHPRuntime extends GenericRuntime
     {
-        private $port;
+        private int $port;
 
         public function __construct(array $options)
         {
diff --git a/components/serializer.rst b/components/serializer.rst
index 26336dc5f9b..33fc71e4b69 100644
--- a/components/serializer.rst
+++ b/components/serializer.rst
@@ -244,9 +244,9 @@ Assume you have the following plain-old-PHP object::
 
     class MyObj
     {
-        public $foo;
+        public string $foo;
 
-        private $bar;
+        private string $bar;
 
         public function getBar()
         {
@@ -303,10 +303,10 @@ Then, create your groups definition:
         class MyObj
         {
             #[Groups(['group1', 'group2'])]
-            public $foo;
+            public string $foo;
 
             #[Groups(['group4'])]
-            public $anotherProperty;
+            public string $anotherProperty;
 
             #[Groups(['group3'])]
             public function getBar() // is* methods are also supported
@@ -449,10 +449,10 @@ Option 1: Using ``@Ignore`` Annotation
 
         class MyClass
         {
-            public $foo;
+            public string $foo;
 
             #[Ignore]
-            public $bar;
+            public string $bar;
         }
 
     .. code-block:: yaml
@@ -1229,8 +1229,8 @@ You can change this behavior by setting the ``AbstractObjectNormalizer::SKIP_NUL
 to ``true``::
 
     $dummy = new class {
-        public $foo;
-        public $bar = 'notNull';
+        public ?string $foo = null;
+        public string $bar = 'notNull';
     };
 
     $normalizer = new ObjectNormalizer();
@@ -1305,8 +1305,8 @@ Circular references are common when dealing with entity relations::
 
     class Organization
     {
-        private $name;
-        private $members;
+        private string $name;
+        private array $members;
 
         public function setName($name)
         {
@@ -1331,10 +1331,10 @@ Circular references are common when dealing with entity relations::
 
     class Member
     {
-        private $name;
-        private $organization;
+        private string $name;
+        private Organization $organization;
 
-        public function setName($name)
+        public function setName(string $name)
         {
             $this->name = $name;
         }
@@ -1404,12 +1404,12 @@ structure::
 
     class MyObj
     {
-        public $foo;
+        public string $foo;
 
         /**
          * @var self
          */
-        public $child;
+        public MyObj $child;
     }
 
     $level1 = new MyObj();
@@ -1437,7 +1437,7 @@ Here, we set it to 2 for the ``$child`` property:
         class MyObj
         {
             #[MaxDepth(2)]
-            public $child;
+            public MyObj $child;
 
             // ...
         }
@@ -1499,10 +1499,10 @@ having unique identifiers::
 
     class Foo
     {
-        public $id;
+        public int $id;
 
         #[MaxDepth(1)]
-        public $child;
+        public MyObj $child;
     }
 
     $level1 = new Foo();
@@ -1598,8 +1598,8 @@ context option::
     class MyObj
     {
         public function __construct(
-            private $foo,
-            private $bar,
+            private string $foo,
+            private string $bar,
         ) {
         }
     }
@@ -1638,8 +1638,8 @@ parameter of the ``ObjectNormalizer``::
 
     class ObjectOuter
     {
-        private $inner;
-        private $date;
+        private ObjectInner $inner;
+        private \DateTimeInterface $date;
 
         public function getInner()
         {
@@ -1664,8 +1664,8 @@ parameter of the ``ObjectNormalizer``::
 
     class ObjectInner
     {
-        public $foo;
-        public $bar;
+        public string $foo;
+        public string $bar;
     }
 
     $normalizer = new ObjectNormalizer(null, null, null, new ReflectionExtractor());
diff --git a/components/validator/metadata.rst b/components/validator/metadata.rst
index 07ee9c52d79..5a88dab76ed 100755
--- a/components/validator/metadata.rst
+++ b/components/validator/metadata.rst
@@ -17,7 +17,7 @@ the ``Author`` class has at least 3 characters::
 
     class Author
     {
-        private $firstName;
+        private string $firstName;
 
         public static function loadValidatorMetadata(ClassMetadata $metadata)
         {
diff --git a/configuration/using_parameters_in_dic.rst b/configuration/using_parameters_in_dic.rst
index 05008114e01..852b06506ce 100644
--- a/configuration/using_parameters_in_dic.rst
+++ b/configuration/using_parameters_in_dic.rst
@@ -101,11 +101,10 @@ be injected with this parameter via the extension as follows::
 
     class Configuration implements ConfigurationInterface
     {
-        private $debug;
+        private bool $debug;
 
-        public function __construct($debug)
+        public function __construct(private bool $debug)
         {
-            $this->debug = (bool) $debug;
         }
 
         public function getConfigTreeBuilder()
diff --git a/contributing/code/standards.rst b/contributing/code/standards.rst
index 69d0a2c16b3..7d16e0f9d0b 100644
--- a/contributing/code/standards.rst
+++ b/contributing/code/standards.rst
@@ -49,10 +49,7 @@ short example containing most features described below::
     {
         public const SOME_CONST = 42;
 
-        /**
-         * @var string
-         */
-        private $fooBar;
+        private string $fooBar;
 
         /**
          * @param $dummy some argument description
diff --git a/controller/upload_file.rst b/controller/upload_file.rst
index 9bcc17cd7cd..dc132e3d021 100644
--- a/controller/upload_file.rst
+++ b/controller/upload_file.rst
@@ -22,7 +22,7 @@ add a PDF brochure for each product. To do so, add a new property called
         // ...
 
         #[ORM\Column(type: 'string')]
-        private $brochureFilename;
+        private string $brochureFilename;
 
         public function getBrochureFilename(): string
         {
@@ -238,7 +238,7 @@ logic to a separate service::
     class FileUploader
     {
         public function __construct(
-            private $targetDirectory,
+            private string $targetDirectory,
             private SluggerInterface $slugger,
         ) {
         }
diff --git a/doctrine/associations.rst b/doctrine/associations.rst
index e1cd113ae22..b17877c4bdf 100644
--- a/doctrine/associations.rst
+++ b/doctrine/associations.rst
@@ -148,7 +148,7 @@ the ``Product`` entity (and getter & setter methods):
             // ...
 
             #[ORM\ManyToOne(targetEntity: Category::class, inversedBy: 'products')]
-            private $category;
+            private Category $category;
 
             public function getCategory(): ?Category
             {
@@ -220,7 +220,7 @@ class that will hold these objects:
             // ...
 
             #[ORM\OneToMany(targetEntity: Product::class, mappedBy: 'category')]
-            private $products;
+            private array $products;
 
             public function __construct()
             {
@@ -588,7 +588,7 @@ that behavior, use the `orphanRemoval`_ option inside ``Category``:
         // ...
 
         #[ORM\OneToMany(targetEntity: Product::class, mappedBy: 'category', orphanRemoval: true)]
-        private $products;
+        private array $products;
 
 
 Thanks to this, if the ``Product`` is removed from the ``Category``, it will be
diff --git a/form/create_form_type_extension.rst b/form/create_form_type_extension.rst
index 43e6b7f198e..7f40b9decc9 100644
--- a/form/create_form_type_extension.rst
+++ b/form/create_form_type_extension.rst
@@ -107,7 +107,7 @@ the database::
         /**
          * @var string The path - typically stored in the database
          */
-        private $path;
+        private string $path;
 
         // ...
 
diff --git a/form/inherit_data_option.rst b/form/inherit_data_option.rst
index 64001ba074d..19b14b27bcd 100644
--- a/form/inherit_data_option.rst
+++ b/form/inherit_data_option.rst
@@ -10,13 +10,13 @@ entities, a ``Company`` and a ``Customer``::
 
     class Company
     {
-        private $name;
-        private $website;
+        private string $name;
+        private string $website;
 
-        private $address;
-        private $zipcode;
-        private $city;
-        private $country;
+        private string $address;
+        private string $zipcode;
+        private string $city;
+        private string $country;
     }
 
 .. code-block:: php
@@ -26,13 +26,13 @@ entities, a ``Company`` and a ``Customer``::
 
     class Customer
     {
-        private $firstName;
-        private $lastName;
+        private string $firstName;
+        private string $lastName;
 
-        private $address;
-        private $zipcode;
-        private $city;
-        private $country;
+        private string  $address;
+        private string $zipcode;
+        private string $city;
+        private string $country;
     }
 
 As you can see, each entity shares a few of the same fields: ``address``,
diff --git a/form/unit_testing.rst b/form/unit_testing.rst
index bcd82a1ee38..048a3c7c0d0 100644
--- a/form/unit_testing.rst
+++ b/form/unit_testing.rst
@@ -154,7 +154,7 @@ make sure the ``FormRegistry`` uses the created instance::
 
     class TestedTypeTest extends TypeTestCase
     {
-        private $objectManager;
+        private MockObject|ObjectManager $objectManager;
 
         protected function setUp(): void
         {
diff --git a/form/use_empty_data.rst b/form/use_empty_data.rst
index 85d6d750a25..5387820693b 100644
--- a/form/use_empty_data.rst
+++ b/form/use_empty_data.rst
@@ -51,7 +51,7 @@ that constructor with no arguments::
     class BlogType extends AbstractType
     {
         public function __construct(
-            private $someDependency,
+            private object $someDependency,
         ) {
         }
         // ...
diff --git a/form/validation_group_service_resolver.rst b/form/validation_group_service_resolver.rst
index da07585b511..82a6f65d6ec 100644
--- a/form/validation_group_service_resolver.rst
+++ b/form/validation_group_service_resolver.rst
@@ -14,8 +14,8 @@ parameter::
     class ValidationGroupResolver
     {
         public function __construct(
-            private $service1,
-            private $service2,
+            private object $service1,
+            private object $service2,
         ) {
         }
 
diff --git a/quick_tour/flex_recipes.rst b/quick_tour/flex_recipes.rst
index 7829304e995..a71961d78af 100644
--- a/quick_tour/flex_recipes.rst
+++ b/quick_tour/flex_recipes.rst
@@ -200,13 +200,13 @@ rich API for a ``product`` table? Create a ``Product`` entity and give it the
         #[ORM\Id]
         #[ORM\GeneratedValue(strategy: 'AUTO')]
         #[ORM\Column(type: 'integer')]
-        private $id;
+        private int $id;
 
         #[ORM\Column(type: 'string')]
-        private $name;
+        private string $name;
 
         #[ORM\Column(type: 'integer')]
-        private $price;
+        private int $price;
 
         // ...
     }
diff --git a/reference/constraints/Callback.rst b/reference/constraints/Callback.rst
index 62184f805cd..2a14eff4531 100644
--- a/reference/constraints/Callback.rst
+++ b/reference/constraints/Callback.rst
@@ -99,7 +99,7 @@ field those errors should be attributed::
     class Author
     {
         // ...
-        private $firstName;
+        private string $firstName;
 
         public function validate(ExecutionContextInterface $context, $payload)
         {
diff --git a/reference/constraints/Expression.rst b/reference/constraints/Expression.rst
index a51002040c0..26192069a8c 100644
--- a/reference/constraints/Expression.rst
+++ b/reference/constraints/Expression.rst
@@ -26,9 +26,9 @@ properties::
 
     class BlogPost
     {
-        private $category;
+        private string $category;
 
-        private $isTechnicalPost;
+        private bool $isTechnicalPost;
 
         // ...
 
@@ -155,7 +155,7 @@ assert that the expression must return ``true`` for validation to fail.
                     "this.getCategory() in ['php', 'symfony'] or value == false",
                     message: 'If this is a tech post, the category should be either php or symfony!',
                 )]
-                private $isTechnicalPost;
+                private bool $isTechnicalPost;
 
                 // ...
             }
@@ -298,7 +298,7 @@ type (numeric, boolean, strings, null, etc.)
                 'value + error_margin < threshold',
                 values: ['error_margin' => 0.25, 'threshold' => 1.5],
             )]
-            private $metric;
+            private float $metric;
 
             // ...
         }
diff --git a/reference/constraints/Json.rst b/reference/constraints/Json.rst
index 1ab6ce46494..04cd4d1c1e1 100644
--- a/reference/constraints/Json.rst
+++ b/reference/constraints/Json.rst
@@ -28,7 +28,7 @@ The ``Json`` constraint can be applied to a property or a "getter" method:
             #[Assert\Json(
                 message: "You've entered an invalid Json."
             )]
-            private $chapters;
+            private string $chapters;
         }
 
     .. code-block:: yaml
diff --git a/routing/custom_route_loader.rst b/routing/custom_route_loader.rst
index 5caf51e8213..ec3b5efcb1b 100644
--- a/routing/custom_route_loader.rst
+++ b/routing/custom_route_loader.rst
@@ -278,7 +278,7 @@ you do. The resource name itself is not actually used in the example::
 
     class ExtraLoader extends Loader
     {
-        private $isLoaded = false;
+        private bool $isLoaded = false;
 
         public function load($resource, string $type = null)
         {
diff --git a/service_container/autowiring.rst b/service_container/autowiring.rst
index 4f62e24e10f..72bb7851965 100644
--- a/service_container/autowiring.rst
+++ b/service_container/autowiring.rst
@@ -653,7 +653,7 @@ to inject the ``logger`` service, and decide to use setter-injection:
 
         class Rot13Transformer
         {
-            private $logger;
+            private LoggerInterface $logger;
 
             #[Required]
             public function setLogger(LoggerInterface $logger): void
diff --git a/service_container/calls.rst b/service_container/calls.rst
index 9f4e3699b18..cb364b59489 100644
--- a/service_container/calls.rst
+++ b/service_container/calls.rst
@@ -17,7 +17,7 @@ example::
 
     class MessageGenerator
     {
-        private $logger;
+        private LoggerInterface $logger;
 
         public function setLogger(LoggerInterface $logger): void
         {
@@ -84,7 +84,7 @@ instead of mutating the object they were called on::
 
     class MessageGenerator
     {
-        private $logger;
+        private LoggerInterface $logger;
 
         public function withLogger(LoggerInterface $logger): self
         {
diff --git a/service_container/configurators.rst b/service_container/configurators.rst
index 2cf9cdb471f..7817a383761 100644
--- a/service_container/configurators.rst
+++ b/service_container/configurators.rst
@@ -23,7 +23,7 @@ You start defining a ``NewsletterManager`` class like this::
 
     class NewsletterManager implements EmailFormatterAwareInterface
     {
-        private $enabledFormatters;
+        private array $enabledFormatters;
 
         public function setEnabledFormatters(array $enabledFormatters): void
         {
@@ -40,7 +40,7 @@ and also a ``GreetingCardManager`` class::
 
     class GreetingCardManager implements EmailFormatterAwareInterface
     {
-        private $enabledFormatters;
+        private array $enabledFormatters;
 
         public function setEnabledFormatters(array $enabledFormatters): void
         {
diff --git a/service_container/injection_types.rst b/service_container/injection_types.rst
index f1a6c80397b..5fb3d09a9c5 100644
--- a/service_container/injection_types.rst
+++ b/service_container/injection_types.rst
@@ -115,7 +115,7 @@ by cloning the original service, this approach allows you to make a service immu
 
     class NewsletterManager
     {
-        private $mailer;
+        private MailerInterface $mailer;
 
         /**
          * @return static
@@ -222,7 +222,7 @@ that accepts the dependency::
     // ...
     class NewsletterManager
     {
-        private $mailer;
+        private MailerInterface $mailer;
 
         #[Required]
         public function setMailer(MailerInterface $mailer): void
diff --git a/service_container/service_decoration.rst b/service_container/service_decoration.rst
index b772fbd2ad3..73b83271025 100644
--- a/service_container/service_decoration.rst
+++ b/service_container/service_decoration.rst
@@ -154,7 +154,7 @@ automatically changed to ``'.inner'``):
         {
             public function __construct(
                 #[MapDecorated]
-                private $inner,
+                private object $inner,
             ) {
             }
 
diff --git a/service_container/tags.rst b/service_container/tags.rst
index 54c5c3cb461..31fe56cacc6 100644
--- a/service_container/tags.rst
+++ b/service_container/tags.rst
@@ -229,12 +229,7 @@ To begin with, define the ``TransportChain`` class::
 
     class TransportChain
     {
-        private $transports;
-
-        public function __construct()
-        {
-            $this->transports = [];
-        }
+        private array $transports = [];
 
         public function addTransport(\MailerTransport $transport): void
         {
@@ -423,12 +418,7 @@ To begin with, change the ``TransportChain`` class::
 
     class TransportChain
     {
-        private $transports;
-
-        public function __construct()
-        {
-            $this->transports = [];
-        }
+        private array $transports = [];
 
         public function addTransport(\MailerTransport $transport, $alias): void
         {
diff --git a/testing/database.rst b/testing/database.rst
index fb78d33a3a7..bce96353da8 100644
--- a/testing/database.rst
+++ b/testing/database.rst
@@ -98,10 +98,7 @@ so, get the entity manager via the service container as follows::
 
     class ProductRepositoryTest extends KernelTestCase
     {
-        /**
-         * @var \Doctrine\ORM\EntityManager
-         */
-        private $entityManager;
+        private \Doctrine\ORM\EntityManager $entityManager;
 
         protected function setUp(): void
         {
diff --git a/validation/groups.rst b/validation/groups.rst
index 51981375e0e..22af24473be 100644
--- a/validation/groups.rst
+++ b/validation/groups.rst
@@ -23,14 +23,14 @@ user registers and when a user updates their contact information later:
         class User implements UserInterface
         {
             #[Assert\Email(groups: ['registration'])]
-            private $email;
+            private string $email;
 
             #[Assert\NotBlank(groups: ['registration'])]
             #[Assert\Length(min: 7, groups: ['registration'])]
-            private $password;
+            private string $password;
 
             #[Assert\Length(min: 2)]
-            private $city;
+            private string $city;
         }
 
     .. code-block:: yaml
diff --git a/validation/sequence_provider.rst b/validation/sequence_provider.rst
index 4ceb289a615..d409b1a203a 100644
--- a/validation/sequence_provider.rst
+++ b/validation/sequence_provider.rst
@@ -23,10 +23,10 @@ username and the password are different only if all other validation passes
         class User implements UserInterface
         {
             #[Assert\NotBlank]
-            private $username;
+            private string $username;
 
             #[Assert\NotBlank]
-            private $password;
+            private string $password;
 
             #[Assert\IsTrue(
                 message: 'The password cannot match your username',
@@ -180,13 +180,13 @@ entity and a new constraint group called ``Premium``:
         class User
         {
             #[Assert\NotBlank]
-            private $name;
+            private string $name;
 
             #[Assert\CardScheme(
                 schemes: [Assert\CardScheme::VISA],
                 groups: ['Premium'],
             )]
-            private $creditCard;
+            private string $creditCard;
 
             // ...
         }
@@ -241,8 +241,8 @@ entity and a new constraint group called ``Premium``:
 
         class User
         {
-            private $name;
-            private $creditCard;
+            private string $name;
+            private string $creditCard;
 
             // ...