diff --git a/composer.json b/composer.json
index 49236ee763b5..57277bc5011b 100644
--- a/composer.json
+++ b/composer.json
@@ -29,7 +29,7 @@
         "phpunit/phpcov": "^9.0.2 || ^10.0",
         "phpunit/phpunit": "^10.5.16 || ^11.2",
         "predis/predis": "^3.0",
-        "rector/rector": "2.5.2",
+        "rector/rector": "2.5.3",
         "shipmonk/phpstan-baseline-per-identifier": "^2.0"
     },
     "replace": {
diff --git a/rector.php b/rector.php
index dcf59d665e7f..c3a1b22ad716 100644
--- a/rector.php
+++ b/rector.php
@@ -12,6 +12,7 @@
  */
 
 use Rector\Caching\ValueObject\Storage\FileCacheStorage;
+use Rector\CodeQuality\Rector\BooleanNot\NegatedAndsToPositiveOrsRector;
 use Rector\CodeQuality\Rector\Empty_\SimplifyEmptyCheckOnEmptyArrayRector;
 use Rector\CodeQuality\Rector\FuncCall\CompactToVariablesRector;
 use Rector\CodeQuality\Rector\FunctionLike\SimplifyUselessVariableRector;
@@ -22,6 +23,7 @@
 use Rector\CodingStyle\Rector\FuncCall\CountArrayToEmptyArrayComparisonRector;
 use Rector\CodingStyle\Rector\FuncCall\VersionCompareFuncCallToConstantRector;
 use Rector\Config\RectorConfig;
+use Rector\DeadCode\Rector\ClassMethod\RemoveDuplicatedReturnSelfDocblockRector;
 use Rector\DeadCode\Rector\ClassMethod\RemoveUnusedConstructorParamRector;
 use Rector\DeadCode\Rector\ClassMethod\RemoveUnusedPrivateMethodRector;
 use Rector\DeadCode\Rector\MethodCall\RemoveNullArgOnNullDefaultParamRector;
@@ -36,7 +38,6 @@
 use Rector\PHPUnit\CodeQuality\Rector\Class_\YieldDataProviderRector;
 use Rector\PHPUnit\CodeQuality\Rector\FuncCall\AssertFuncCallToPHPUnitAssertRector;
 use Rector\PHPUnit\CodeQuality\Rector\StmtsAwareInterface\DeclareStrictTypesTestsRector;
-use Rector\PostRector\Rector\UnusedImportRemovingPostRector;
 use Rector\Privatization\Rector\Class_\FinalizeTestCaseClassRector;
 use Rector\Privatization\Rector\Property\PrivatizeFinalClassPropertyRector;
 use Rector\Renaming\Rector\ConstFetch\RenameConstantRector;
@@ -175,10 +176,9 @@
             __DIR__ . '/tests/system/Models',
         ],
 
-        UnusedImportRemovingPostRector::class => [
-            // buggy on auto import removed
-            __DIR__ . '/system/HTTP/Response.php',
-        ],
+        // to be applied in separate PRs to ease review
+        NegatedAndsToPositiveOrsRector::class,
+        RemoveDuplicatedReturnSelfDocblockRector::class,
     ])
     // auto import fully qualified class names
     ->withImportNames()
diff --git a/system/Database/BaseBuilder.php b/system/Database/BaseBuilder.php
index ce87de3c356f..f1a9428c13eb 100644
--- a/system/Database/BaseBuilder.php
+++ b/system/Database/BaseBuilder.php
@@ -2686,7 +2686,7 @@ protected function _updateBatch(string $table, array $keys, array $values): stri
             $sql .= 'WHERE ' . implode(
                 ' AND ',
                 array_map(
-                    static fn ($key, $value) => (
+                    static fn ($key, $value): RawSql|string => (
                         ($value instanceof RawSql && is_string($key))
                         ?
                         $table . '.' . $key . ' = ' . $value
@@ -2936,7 +2936,7 @@ protected function _deleteBatch(string $table, array $keys, array $values): stri
             $sql .= 'ON ' . implode(
                 ' AND ',
                 array_map(
-                    static fn ($key, $value) => (
+                    static fn ($key, $value): RawSql|string => (
                         $value instanceof RawSql ?
                         $value :
                         (
diff --git a/system/Database/MySQLi/Builder.php b/system/Database/MySQLi/Builder.php
index a9e248fc4584..bba90421e9e4 100644
--- a/system/Database/MySQLi/Builder.php
+++ b/system/Database/MySQLi/Builder.php
@@ -92,7 +92,7 @@ protected function _updateBatch(string $table, array $keys, array $values): stri
             $sql .= 'ON ' . implode(
                 ' AND ',
                 array_map(
-                    static fn ($key, $value) => (
+                    static fn ($key, $value): RawSql|string => (
                         ($value instanceof RawSql && is_string($key))
                         ?
                         $table . '.' . $key . ' = ' . $value
diff --git a/system/Database/OCI8/Builder.php b/system/Database/OCI8/Builder.php
index 59195b3b533a..ff5b1289c34a 100644
--- a/system/Database/OCI8/Builder.php
+++ b/system/Database/OCI8/Builder.php
@@ -248,7 +248,7 @@ protected function _updateBatch(string $table, array $keys, array $values): stri
             $sql .= 'ON (' . implode(
                 ' AND ',
                 array_map(
-                    static fn ($key, $value) => (
+                    static fn ($key, $value): RawSql|string => (
                         ($value instanceof RawSql && is_string($key))
                         ?
                         $table . '.' . $key . ' = ' . $value
@@ -353,7 +353,7 @@ protected function _upsertBatch(string $table, array $keys, array $values): stri
             $sql .= implode(
                 ' AND ',
                 array_map(
-                    static fn ($key, $value) => (
+                    static fn ($key, $value): RawSql|string => (
                         ($value instanceof RawSql && is_string($key))
                         ?
                         $table . '.' . $key . ' = ' . $value
@@ -442,7 +442,7 @@ protected function _deleteBatch(string $table, array $keys, array $values): stri
             $sql .= 'WHERE ' . implode(
                 ' AND ',
                 array_map(
-                    static fn ($key, $value) => (
+                    static fn ($key, $value): RawSql|string => (
                         $value instanceof RawSql ?
                         $value :
                         (
diff --git a/system/Database/SQLSRV/Builder.php b/system/Database/SQLSRV/Builder.php
index 098b08599808..cd7e7968fe72 100644
--- a/system/Database/SQLSRV/Builder.php
+++ b/system/Database/SQLSRV/Builder.php
@@ -752,7 +752,7 @@ protected function _upsertBatch(string $table, array $keys, array $values): stri
             $sql .= implode(
                 ' AND ',
                 array_map(
-                    static fn ($key, $value) => (
+                    static fn ($key, $value): RawSql|string => (
                         ($value instanceof RawSql && is_string($key))
                         ?
                         $fullTableName . '.' . $key . ' = ' . $value
diff --git a/tests/system/Test/FeatureTestTraitTest.php b/tests/system/Test/FeatureTestTraitTest.php
index f36767f7f971..79a00104a079 100644
--- a/tests/system/Test/FeatureTestTraitTest.php
+++ b/tests/system/Test/FeatureTestTraitTest.php
@@ -412,7 +412,7 @@ public function testCallGetWithParams(): void
             [
                 'GET',
                 'home',
-                static fn () => json_encode(service('request')->getGet()),
+                static fn (): false|string => json_encode(service('request')->getGet()),
             ],
         ]);
         $data = [
@@ -439,7 +439,7 @@ public function testCallGetWithParamsAndREQUEST(): void
             [
                 'GET',
                 'home',
-                static fn () => json_encode(service('request')->fetchGlobal('request')),
+                static fn (): false|string => json_encode(service('request')->fetchGlobal('request')),
             ],
         ]);
         $data = [
@@ -466,7 +466,7 @@ public function testCallPostWithParams(): void
             [
                 'POST',
                 'home',
-                static fn () => json_encode(service('request')->getPost()),
+                static fn (): false|string => json_encode(service('request')->getPost()),
             ],
         ]);
         $data = [
@@ -493,7 +493,7 @@ public function testCallPostWithParamsAndREQUEST(): void
             [
                 'POST',
                 'home',
-                static fn () => json_encode(service('request')->fetchGlobal('request')),
+                static fn (): false|string => json_encode(service('request')->fetchGlobal('request')),
             ],
         ]);
         $data = [
@@ -544,7 +544,7 @@ public function testCallPutWithJsonRequestAndREQUEST(): void
             [
                 'PUT',
                 'home',
-                static fn () => json_encode(service('request')->fetchGlobal('request')),
+                static fn (): false|string => json_encode(service('request')->fetchGlobal('request')),
             ],
         ]);
         $data = [