diff --git a/config/level/code-quality/code-quality.yaml b/config/level/code-quality/code-quality.yaml
index d7fef79e5be..fb22d3a423a 100644
--- a/config/level/code-quality/code-quality.yaml
+++ b/config/level/code-quality/code-quality.yaml
@@ -35,3 +35,4 @@ services:
     Rector\CodeQuality\Rector\LogicalAnd\AndAssignsToSeparateLinesRector: ~
     Rector\CodeQuality\Rector\For_\ForToForeachRector: ~
     Rector\CodeQuality\Rector\FuncCall\CompactToVariablesRector: ~
+    Rector\CodeQuality\Rector\Class_\CompleteDynamicPropertiesRector: ~
diff --git a/docs/AllRectorsOverview.md b/docs/AllRectorsOverview.md
index 3561f2a037b..e0a30fc5edb 100644
--- a/docs/AllRectorsOverview.md
+++ b/docs/AllRectorsOverview.md
@@ -1,4 +1,4 @@
-# All 299 Rectors Overview
+# All 300 Rectors Overview
 
 - [Projects](#projects)
 - [General](#general)
@@ -769,6 +769,28 @@ Joins concat of 2 strings
 
 <br>
 
+### `CompleteDynamicPropertiesRector`
+
+- class: `Rector\CodeQuality\Rector\Class_\CompleteDynamicPropertiesRector`
+
+Add missing dynamic properties
+
+```diff
+ class SomeClass
+ {
++    /**
++     * @var int
++     */
++    public $value;
+     public function set()
+     {
+         $this->value = 5;
+     }
+ }
+```
+
+<br>
+
 ## CodingStyle
 
 ### `SplitDoubleAssignRector`
diff --git a/packages/CodeQuality/src/Rector/Class_/CompleteDynamicPropertiesRector.php b/packages/CodeQuality/src/Rector/Class_/CompleteDynamicPropertiesRector.php
new file mode 100644
index 00000000000..0e3d0949ee7
--- /dev/null
+++ b/packages/CodeQuality/src/Rector/Class_/CompleteDynamicPropertiesRector.php
@@ -0,0 +1,189 @@
+<?php declare(strict_types=1);
+
+namespace Rector\CodeQuality\Rector\Class_;
+
+use Nette\Utils\Arrays;
+use PhpParser\Node;
+use PhpParser\Node\Expr\Assign;
+use PhpParser\Node\Expr\PropertyFetch;
+use PhpParser\Node\Stmt\Class_;
+use PhpParser\Node\Stmt\Property;
+use Rector\NodeTypeResolver\Node\AttributeKey;
+use Rector\NodeTypeResolver\PhpDoc\NodeAnalyzer\DocBlockManipulator;
+use Rector\NodeTypeResolver\PHPStan\Type\TypeToStringResolver;
+use Rector\PhpParser\NodeTraverser\CallableNodeTraverser;
+use Rector\Rector\AbstractRector;
+use Rector\RectorDefinition\CodeSample;
+use Rector\RectorDefinition\RectorDefinition;
+
+/**
+ * @see https://3v4l.org/GL6II
+ * @see https://3v4l.org/eTrhZ
+ * @see https://3v4l.org/C554W
+ */
+final class CompleteDynamicPropertiesRector extends AbstractRector
+{
+    /**
+     * @var CallableNodeTraverser
+     */
+    private $callableNodeTraverser;
+
+    /**
+     * @var TypeToStringResolver
+     */
+    private $typeToStringResolver;
+
+    /**
+     * @var DocBlockManipulator
+     */
+    private $docBlockManipulator;
+
+    public function __construct(
+        CallableNodeTraverser $callableNodeTraverser,
+        TypeToStringResolver $typeToStringResolver,
+        DocBlockManipulator $docBlockManipulator
+    ) {
+        $this->callableNodeTraverser = $callableNodeTraverser;
+        $this->typeToStringResolver = $typeToStringResolver;
+        $this->docBlockManipulator = $docBlockManipulator;
+    }
+
+    public function getDefinition(): RectorDefinition
+    {
+        return new RectorDefinition('Add missing dynamic properties', [
+            new CodeSample(
+                <<<'CODE_SAMPLE'
+class SomeClass
+{
+    public function set()
+    {
+        $this->value = 5;
+    }
+}
+CODE_SAMPLE
+                ,
+                <<<'CODE_SAMPLE'
+class SomeClass
+{
+    /**
+     * @var int
+     */
+    public $value;
+    public function set()
+    {
+        $this->value = 5;
+    }
+}
+CODE_SAMPLE
+            ),
+        ]);
+    }
+
+    /**
+     * @return string[]
+     */
+    public function getNodeTypes(): array
+    {
+        return [Class_::class];
+    }
+
+    /**
+     * @param Class_ $node
+     */
+    public function refactor(Node $node): ?Node
+    {
+        $fetchedLocalPropertyNameToTypes = $this->resolveFetchedLocalPropertyNameToTypes($node);
+
+        $propertyNames = [];
+        $this->callableNodeTraverser->traverseNodesWithCallable($node->stmts, function (Node $node) use (
+            &$propertyNames
+        ) {
+            if (! $node instanceof Property) {
+                return null;
+            }
+
+            $propertyNames[] = $this->getName($node);
+        });
+
+        $fetchedLocalPropertyNames = array_keys($fetchedLocalPropertyNameToTypes);
+        $propertiesToComplete = array_diff($fetchedLocalPropertyNames, $propertyNames);
+
+        $newProperties = $this->createNewProperties($fetchedLocalPropertyNameToTypes, $propertiesToComplete);
+
+        $node->stmts = array_merge_recursive($newProperties, $node->stmts);
+
+        return $node;
+    }
+
+    /**
+     * @param string[][][] $fetchedLocalPropertyNameToTypes
+     * @param string[] $propertiesToComplete
+     * @return Property[]
+     */
+    private function createNewProperties(array $fetchedLocalPropertyNameToTypes, array $propertiesToComplete): array
+    {
+        $newProperties = [];
+        foreach ($fetchedLocalPropertyNameToTypes as $propertyName => $propertyTypes) {
+            if (! in_array($propertyName, $propertiesToComplete, true)) {
+                continue;
+            }
+
+            $propertyTypes = Arrays::flatten($propertyTypes);
+            $propertyTypesAsString = implode('|', $propertyTypes);
+
+            $propertyBuilder = $this->builderFactory->property($propertyName)
+                ->makePublic();
+
+            if ($this->isAtLeastPhpVersion('7.4') && count($propertyTypes) === 1) {
+                $newProperty = $propertyBuilder->setType($propertyTypes[0])
+                    ->getNode();
+            } else {
+                $newProperty = $propertyBuilder->getNode();
+                $this->docBlockManipulator->changeVarTag($newProperty, $propertyTypesAsString);
+            }
+
+            $newProperties[] = $newProperty;
+        }
+        return $newProperties;
+    }
+
+    /**
+     * @return string[][][]
+     */
+    private function resolveFetchedLocalPropertyNameToTypes(Class_ $class): array
+    {
+        $fetchedLocalPropertyNameToTypes = [];
+
+        $this->callableNodeTraverser->traverseNodesWithCallable($class->stmts, function (Node $node) use (
+            &$fetchedLocalPropertyNameToTypes
+        ) {
+            if (! $node instanceof PropertyFetch) {
+                return null;
+            }
+
+            if (! $this->isName($node->var, 'this')) {
+                return null;
+            }
+
+            $parentNode = $node->getAttribute(AttributeKey::PARENT_NODE);
+
+            // fallback type
+            $propertyFetchType = ['mixed'];
+
+            // possible get type
+            if ($parentNode instanceof Assign) {
+                $assignedValueStaticType = $this->getStaticType($parentNode->expr);
+                if ($assignedValueStaticType) {
+                    $propertyFetchType = $this->typeToStringResolver->resolve($assignedValueStaticType);
+                }
+            }
+
+            /** @var string $propertyName */
+            $propertyName = $this->getName($node->name);
+
+            $fetchedLocalPropertyNameToTypes[$propertyName][] = $propertyFetchType;
+        });
+
+        return $fetchedLocalPropertyNameToTypes;
+    }
+}
diff --git a/packages/CodeQuality/tests/Rector/Class_/CompleteDynamicPropertiesRector/CompleteDynamicPropertiesRectorTest.php b/packages/CodeQuality/tests/Rector/Class_/CompleteDynamicPropertiesRector/CompleteDynamicPropertiesRectorTest.php
new file mode 100644
index 00000000000..14e02a926b0
--- /dev/null
+++ b/packages/CodeQuality/tests/Rector/Class_/CompleteDynamicPropertiesRector/CompleteDynamicPropertiesRectorTest.php
@@ -0,0 +1,23 @@
+<?php declare(strict_types=1);
+
+namespace Rector\CodeQuality\Tests\Rector\Class_\CompleteDynamicPropertiesRector;
+
+use Rector\CodeQuality\Rector\Class_\CompleteDynamicPropertiesRector;
+use Rector\Testing\PHPUnit\AbstractRectorTestCase;
+
+final class CompleteDynamicPropertiesRectorTest extends AbstractRectorTestCase
+{
+    public function test(): void
+    {
+        $this->doTestFiles([
+            __DIR__ . '/Fixture/fixture.php.inc',
+            __DIR__ . '/Fixture/multiple_types.php.inc',
+            __DIR__ . '/Fixture/skip_defined.php.inc',
+        ]);
+    }
+
+    protected function getRectorClass(): string
+    {
+        return CompleteDynamicPropertiesRector::class;
+    }
+}
diff --git a/packages/CodeQuality/tests/Rector/Class_/CompleteDynamicPropertiesRector/Fixture/fixture.php.inc b/packages/CodeQuality/tests/Rector/Class_/CompleteDynamicPropertiesRector/Fixture/fixture.php.inc
new file mode 100644
index 00000000000..b36a4b6212c
--- /dev/null
+++ b/packages/CodeQuality/tests/Rector/Class_/CompleteDynamicPropertiesRector/Fixture/fixture.php.inc
@@ -0,0 +1,28 @@
+<?php
+
+namespace Rector\CodeQuality\Tests\Rector\Class_\CompleteDynamicPropertiesRector\Fixture;
+
+class SomeClass
+{
+    public function set()
+    {
+        $this->value = 5;
+    }
+}
+
+?>
+-----
+<?php
+
+namespace Rector\CodeQuality\Tests\Rector\Class_\CompleteDynamicPropertiesRector\Fixture;
+
+class SomeClass
+{
+    public int $value;
+    public function set()
+    {
+        $this->value = 5;
+    }
+}
+
+?>
diff --git a/packages/CodeQuality/tests/Rector/Class_/CompleteDynamicPropertiesRector/Fixture/multiple_types.php.inc b/packages/CodeQuality/tests/Rector/Class_/CompleteDynamicPropertiesRector/Fixture/multiple_types.php.inc
new file mode 100644
index 00000000000..570b3fb2621
--- /dev/null
+++ b/packages/CodeQuality/tests/Rector/Class_/CompleteDynamicPropertiesRector/Fixture/multiple_types.php.inc
@@ -0,0 +1,35 @@
+<?php
+
+namespace Rector\CodeQuality\Tests\Rector\Class_\CompleteDynamicPropertiesRector\Fixture;
+
+class MultipleTypes
+{
+    public function set()
+    {
+        $this->value = 5;
+
+        $this->value = 'hey';
+    }
+}
+
+?>
+-----
+<?php
+
+namespace Rector\CodeQuality\Tests\Rector\Class_\CompleteDynamicPropertiesRector\Fixture;
+
+class MultipleTypes
+{
+    /**
+     * @var int|string
+     */
+    public $value;
+    public function set()
+    {
+        $this->value = 5;
+
+        $this->value = 'hey';
+    }
+}
+
+?>
diff --git a/packages/CodeQuality/tests/Rector/Class_/CompleteDynamicPropertiesRector/Fixture/skip_defined.php.inc b/packages/CodeQuality/tests/Rector/Class_/CompleteDynamicPropertiesRector/Fixture/skip_defined.php.inc
new file mode 100644
index 00000000000..12e1a3aa583
--- /dev/null
+++ b/packages/CodeQuality/tests/Rector/Class_/CompleteDynamicPropertiesRector/Fixture/skip_defined.php.inc
@@ -0,0 +1,12 @@
+<?php
+
+namespace Rector\CodeQuality\Tests\Rector\Class_\CompleteDynamicPropertiesRector\Fixture;
+
+class SkipDefined
+{
+    private $value;
+    public function set()
+    {
+        $this->value = 5;
+    }
+}
diff --git a/packages/Php/src/Rector/Property/TypedPropertyRector.php b/packages/Php/src/Rector/Property/TypedPropertyRector.php
index 90903c9749e..437d47e3ead 100644
--- a/packages/Php/src/Rector/Property/TypedPropertyRector.php
+++ b/packages/Php/src/Rector/Property/TypedPropertyRector.php
@@ -96,6 +96,7 @@ CODE_SAMPLE
             return null;
         }
 
+        // type is already set → skip
         if ($node->type !== null) {
             return null;
         }