diff --git a/application/Espo/Controllers/ExternalAccount.php b/application/Espo/Controllers/ExternalAccount.php
index 0c5720a33f..98f3cd1e63 100644
--- a/application/Espo/Controllers/ExternalAccount.php
+++ b/application/Espo/Controllers/ExternalAccount.php
@@ -38,7 +38,7 @@ use Espo\Core\{
     Record\ReadParams,
 };
 
-use StdClass;
+use stdClass;
 
 class ExternalAccount extends RecordBase
 {
@@ -49,7 +49,7 @@ class ExternalAccount extends RecordBase
         return $this->acl->checkScope('ExternalAccount');
     }
 
-    public function getActionList(Request $request, Response $response): StdClass
+    public function getActionList(Request $request, Response $response): stdClass
     {
         $integrations = $this->entityManager->getRepository('Integration')->find();
 
@@ -81,7 +81,7 @@ class ExternalAccount extends RecordBase
         ];
     }
 
-    public function getActionGetOAuth2Info(Request $request): ?StdClass
+    public function getActionGetOAuth2Info(Request $request): ?stdClass
     {
         $id = $request->getQueryParam('id');
 
@@ -104,7 +104,7 @@ class ExternalAccount extends RecordBase
         return null;
     }
 
-    public function getActionRead(Request $request, Response $response): StdClass
+    public function getActionRead(Request $request, Response $response): stdClass
     {
         $id = $request->getRouteParam('id');
 
@@ -113,7 +113,7 @@ class ExternalAccount extends RecordBase
             ->getValueMap();
     }
 
-    public function putActionUpdate(Request $request, Response $response): StdClass
+    public function putActionUpdate(Request $request, Response $response): stdClass
     {
         $id = $request->getRouteParam('id');
 
diff --git a/application/Espo/Controllers/Notification.php b/application/Espo/Controllers/Notification.php
index 2413061a07..4c62d1a858 100644
--- a/application/Espo/Controllers/Notification.php
+++ b/application/Espo/Controllers/Notification.php
@@ -29,21 +29,19 @@
 
 namespace Espo\Controllers;
 
-use Espo\Core\Exceptions\Error;
-
 use Espo\Core\{
     Controllers\RecordBase,
     Api\Request,
     Api\Response,
 };
 
-use StdClass;
+use stdClass;
 
 class Notification extends RecordBase
 {
     public static $defaultAction = 'list';
 
-    public function getActionList(Request $request, Response $response): StdClass
+    public function getActionList(Request $request, Response $response): stdClass
     {
         $userId = $this->user->getId();
 
diff --git a/application/Espo/Controllers/Webhook.php b/application/Espo/Controllers/Webhook.php
index 6fb2f83256..522eed86ab 100644
--- a/application/Espo/Controllers/Webhook.php
+++ b/application/Espo/Controllers/Webhook.php
@@ -35,7 +35,7 @@ use Espo\Core\{
     Api\Response,
 };
 
-use StdClass;
+use stdClass;
 
 class Webhook extends RecordBase
 {
@@ -48,7 +48,7 @@ class Webhook extends RecordBase
         return true;
     }
 
-    public function postActionCreate(Request $request, Response $response): StdClass
+    public function postActionCreate(Request $request, Response $response): stdClass
     {
         $result = parent::postActionCreate($request, $response);
 
diff --git a/application/Espo/Core/AclPortal/Base.php b/application/Espo/Core/AclPortal/Base.php
index fe94124bc7..b1a818c598 100644
--- a/application/Espo/Core/AclPortal/Base.php
+++ b/application/Espo/Core/AclPortal/Base.php
@@ -35,6 +35,8 @@ use Espo\ORM\Entity;
 
 use Espo\Entities\User;
 
+use Espo\Core\AclManager;
+
 use Espo\Core\{
     ORM\EntityManager,
     Portal\AclManager as PortalAclManager,
diff --git a/application/Espo/Core/Action/Data.php b/application/Espo/Core/Action/Data.php
index 081fb5859e..ebb7ed2032 100644
--- a/application/Espo/Core/Action/Data.php
+++ b/application/Espo/Core/Action/Data.php
@@ -35,6 +35,8 @@ use stdClass;
 
 class Data
 {
+    private $data;
+
     private function __construct()
     {
         $this->data = (object) [];
diff --git a/application/Espo/Core/Api/ErrorOutput.php b/application/Espo/Core/Api/ErrorOutput.php
index ba9eb216e7..b000fa9699 100644
--- a/application/Espo/Core/Api/ErrorOutput.php
+++ b/application/Espo/Core/Api/ErrorOutput.php
@@ -248,7 +248,7 @@ class ErrorOutput
             $logMessageItemList[] = $message;
         }
 
-        $logMessageItemList[] .= $request->getMethod() . ' ' . $request->getResourcePath();
+        $logMessageItemList[] = $request->getMethod() . ' ' . $request->getResourcePath();
 
         if ($requestBodyString) {
             $logMessageItemList[] = "Input data: " . $requestBodyString;
diff --git a/application/Espo/Core/Formula/Functions/ComparisonGroup/Base.php b/application/Espo/Core/Formula/Functions/ComparisonGroup/Base.php
index 7d7c96b839..acb24ec290 100644
--- a/application/Espo/Core/Formula/Functions/ComparisonGroup/Base.php
+++ b/application/Espo/Core/Formula/Functions/ComparisonGroup/Base.php
@@ -47,4 +47,6 @@ abstract class Base extends BaseFunction
 
         return $this->compare($left, $right);
     }
+
+    abstract protected function compare($left, $right);
 }
diff --git a/application/Espo/Core/Formula/Functions/DatetimeGroup/AddIntervalType.php b/application/Espo/Core/Formula/Functions/DatetimeGroup/AddIntervalType.php
index cfa58b7f3b..a9e39e22e8 100644
--- a/application/Espo/Core/Formula/Functions/DatetimeGroup/AddIntervalType.php
+++ b/application/Espo/Core/Formula/Functions/DatetimeGroup/AddIntervalType.php
@@ -48,6 +48,8 @@ abstract class AddIntervalType extends BaseFunction implements Di\DateTimeAware
 
     protected $timeOnly = false;
 
+    protected $intervalTypeString;
+
     public function process(ArgumentList $args)
     {
         $args = $this->evaluate($args);
diff --git a/application/Espo/Core/Formula/Functions/EntityGroup/GetLinkColumnType.php b/application/Espo/Core/Formula/Functions/EntityGroup/GetLinkColumnType.php
index 7d6ee1dec8..f7672beb57 100644
--- a/application/Espo/Core/Formula/Functions/EntityGroup/GetLinkColumnType.php
+++ b/application/Espo/Core/Formula/Functions/EntityGroup/GetLinkColumnType.php
@@ -42,13 +42,15 @@ class GetLinkColumnType extends \Espo\Core\Formula\Functions\Base implements
     {
         $args = $item->value ?? [];
 
-        if (count($args) < 3) throw new Error("Formula: entity\\isRelated: no argument.");
+        if (count($args) < 3) {
+            throw new Error("Formula: entity\\isRelated: no argument.");
+        }
 
         $link = $this->evaluate($args[0]);
         $id = $this->evaluate($args[1]);
         $column = $this->evaluate($args[2]);
 
-        $entityType = $this->getEntity()->getEntityType($entityType);
+        $entityType = $this->getEntity()->getEntityType();
         $repository = $this->entityManager->getRepository($entityType);
 
         return $repository->getRelationColumn($this->getEntity(), $link, $id, $column);
diff --git a/application/Espo/Core/Formula/Manager.php b/application/Espo/Core/Formula/Manager.php
index 94470f7010..a078ed9202 100644
--- a/application/Espo/Core/Formula/Manager.php
+++ b/application/Espo/Core/Formula/Manager.php
@@ -43,6 +43,8 @@ use StdClass;
  */
 class Manager
 {
+    private $evaluator;
+
     public function __construct(InjectableFactory $injectableFactory, Metadata $metadata)
     {
         $functionClassNameMap = $metadata->get(['app', 'formula', 'functionClassNameMap'], []);
diff --git a/application/Espo/Core/Htmlizer/TemplateRenderer.php b/application/Espo/Core/Htmlizer/TemplateRenderer.php
index 50bbbe7772..df939b5031 100644
--- a/application/Espo/Core/Htmlizer/TemplateRenderer.php
+++ b/application/Espo/Core/Htmlizer/TemplateRenderer.php
@@ -55,6 +55,8 @@ class TemplateRenderer
 
     private $applicationState;
 
+    private $template;
+
     public function __construct(HtmlizerFactory $htmlizerFactory, ApplicationState $applicationState)
     {
         $this->htmlizerFactory = $htmlizerFactory;
diff --git a/application/Espo/Core/Mail/Mail/Header/XQueueItemId.php b/application/Espo/Core/Mail/Mail/Header/XQueueItemId.php
index 9c200ddcf4..da27a6c2c4 100644
--- a/application/Espo/Core/Mail/Mail/Header/XQueueItemId.php
+++ b/application/Espo/Core/Mail/Mail/Header/XQueueItemId.php
@@ -36,7 +36,6 @@
 namespace Espo\Core\Mail\Mail\Header;
 
 use Laminas\Mail\Header;
-use Laminas\Mime\Mime;
 
 class XQueueItemId implements Header\HeaderInterface
 {
@@ -47,14 +46,16 @@ class XQueueItemId implements Header\HeaderInterface
     public static function fromString($headerLine)
     {
         list($name, $value) = Header\GenericHeader::splitHeaderLine($headerLine);
-        $value = Header\HeaderWrap::mimeDecodeValue($value);
+
+        $valueDecoded = Header\HeaderWrap::mimeDecodeValue($value);
 
         if (strtolower($name) !== 'x-queue-item-id') {
             throw new Header\Exception\InvalidArgumentException('Invalid header line for x-queue-item-id string');
         }
 
-        $header = new static();
-        $header->setId($value);
+        $header = new self();
+
+        $header->setId($valueDecoded);
 
         return $header;
     }
diff --git a/application/Espo/Core/Mail/Parser.php b/application/Espo/Core/Mail/Parser.php
index d21ca84316..3173af61ba 100644
--- a/application/Espo/Core/Mail/Parser.php
+++ b/application/Espo/Core/Mail/Parser.php
@@ -38,7 +38,7 @@ use Espo\Core\{
     Mail\MessageWrapper
 };
 
-use StdClass;
+use stdClass;
 
 interface Parser
 {
@@ -48,9 +48,9 @@ interface Parser
 
     public function getMessageMessageId(MessageWrapper $message): ?string;
 
-    public function getAddressNameMap(MessageWrapper $message): StdClass;
+    public function getAddressNameMap(MessageWrapper $message): stdClass;
 
-    public function getAddressDataFromMessage(MessageWrapper $message, string $type): ?StdClass;
+    public function getAddressDataFromMessage(MessageWrapper $message, string $type): ?stdClass;
 
     /**
      * @return string[]
diff --git a/application/Espo/Core/MassAction/Data.php b/application/Espo/Core/MassAction/Data.php
index 27741709fc..c9d8afe03f 100644
--- a/application/Espo/Core/MassAction/Data.php
+++ b/application/Espo/Core/MassAction/Data.php
@@ -35,6 +35,8 @@ use stdClass;
 
 class Data
 {
+    private $data;
+
     private function __construct()
     {
         $this->data = (object) [];
diff --git a/application/Espo/Core/ORM/Entity.php b/application/Espo/Core/ORM/Entity.php
index 359aa87727..973b9b134e 100644
--- a/application/Espo/Core/ORM/Entity.php
+++ b/application/Espo/Core/ORM/Entity.php
@@ -51,7 +51,7 @@ class Entity extends BaseEntity
     public function hasLinkParentField(string $field): bool
     {
         return
-            $this->hasAttributeType($field . 'Type') == 'foreignType' &&
+            $this->getAttributeType($field . 'Type') == 'foreignType' &&
             $this->hasAttribute($field . 'Id') &&
             $this->hasRelation($field);
     }
diff --git a/application/Espo/Core/Portal/AclManager.php b/application/Espo/Core/Portal/AclManager.php
index 6fade2ceef..88ab5cb6ff 100644
--- a/application/Espo/Core/Portal/AclManager.php
+++ b/application/Espo/Core/Portal/AclManager.php
@@ -55,7 +55,7 @@ use Espo\Core\{
     AclManager as InternalAclManager,
 };
 
-use StdClass;
+use stdClass;
 use RuntimeException;
 
 class AclManager extends InternalAclManager
@@ -131,7 +131,7 @@ class AclManager extends InternalAclManager
         return $this->mapHashMap[$key];
     }
 
-    public function getMapData(User $user): StdClass
+    public function getMapData(User $user): stdClass
     {
         if ($this->checkUserIsNotPortal($user)) {
             return $this->internalAclManager->getMapData($user);
diff --git a/application/Espo/Core/Portal/Utils/ThemeManager.php b/application/Espo/Core/Portal/Utils/ThemeManager.php
index bd2f16980d..30e004b4bd 100644
--- a/application/Espo/Core/Portal/Utils/ThemeManager.php
+++ b/application/Espo/Core/Portal/Utils/ThemeManager.php
@@ -36,6 +36,8 @@ use Espo\Core\Utils\ThemeManager as BaseThemeManager;
 
 class ThemeManager extends BaseThemeManager
 {
+    private $portal;
+
     public function __construct(Config $config, Metadata $metadata, Portal $portal)
     {
         parent::__construct($config, $metadata);
diff --git a/application/Espo/Services/User.php b/application/Espo/Services/User.php
index 40bfa32e55..fb9bc1e989 100644
--- a/application/Espo/Services/User.php
+++ b/application/Espo/Services/User.php
@@ -45,7 +45,7 @@ use Espo\Core\{
 
 use Espo\ORM\Entity;
 
-use StdClass;
+use stdClass;
 use Exception;
 
 class User extends Record implements
@@ -213,7 +213,7 @@ class User extends Record implements
         $recovery->request($emailAddress, $userName, $url);
     }
 
-    public function changePasswordByRequest(string $requestId, string $password): StdClass
+    public function changePasswordByRequest(string $requestId, string $password): stdClass
     {
         $recovery = $this->injectableFactory->create(Recovery::class);
 
@@ -273,7 +273,7 @@ class User extends Record implements
         }
     }
 
-    public function create(StdClass $data, CreateParams $params): Entity
+    public function create(stdClass $data, CreateParams $params): Entity
     {
         $newPassword = null;
 
@@ -301,7 +301,7 @@ class User extends Record implements
         return $user;
     }
 
-    public function update(string $id, StdClass $data, UpdateParams $params): Entity
+    public function update(string $id, stdClass $data, UpdateParams $params): Entity
     {
         if ($id == 'system') {
             throw new Forbidden();