diff --git a/application/Espo/Controllers/Admin.php b/application/Espo/Controllers/Admin.php
index 323d0b72b2..70fd350e47 100644
--- a/application/Espo/Controllers/Admin.php
+++ b/application/Espo/Controllers/Admin.php
@@ -35,7 +35,7 @@ use Espo\Core\{
     Utils\AdminNotificationManager,
     Utils\SystemRequirements,
     Utils\ScheduledJob,
-    UpgradeManager,
+    Upgrades\UpgradeManager,
     Exceptions\Forbidden,
     Api\Request,
 };
diff --git a/application/Espo/Controllers/Extension.php b/application/Espo/Controllers/Extension.php
index 80ba5a69ee..4831293d65 100644
--- a/application/Espo/Controllers/Extension.php
+++ b/application/Espo/Controllers/Extension.php
@@ -32,7 +32,7 @@ namespace Espo\Controllers;
 use Espo\Core\Exceptions\Forbidden;
 
 use Espo\Core\{
-    ExtensionManager,
+    Upgrades\ExtensionManager,
     Controllers\RecordBase,
     Api\Request,
     Api\Response,
diff --git a/application/Espo/Core/Console/Commands/Extension.php b/application/Espo/Core/Console/Commands/Extension.php
index c46c421c4a..4f45560352 100644
--- a/application/Espo/Core/Console/Commands/Extension.php
+++ b/application/Espo/Core/Console/Commands/Extension.php
@@ -30,7 +30,7 @@
 namespace Espo\Core\Console\Commands;
 
 use Espo\Core\{
-    ExtensionManager,
+    Upgrades\ExtensionManager,
     Container,
     Console\Command,
     Console\Params,
@@ -227,7 +227,7 @@ class Extension implements Command
         }
     }
 
-    protected function createExtensionManager()
+    protected function createExtensionManager(): ExtensionManager
     {
         return new ExtensionManager($this->container);
     }
diff --git a/application/Espo/Core/Console/Commands/Upgrade.php b/application/Espo/Core/Console/Commands/Upgrade.php
index 19470877b3..254332c823 100644
--- a/application/Espo/Core/Console/Commands/Upgrade.php
+++ b/application/Espo/Core/Console/Commands/Upgrade.php
@@ -32,7 +32,7 @@ namespace Espo\Core\Console\Commands;
 use Espo\Core\{
     Exceptions\Error,
     Application,
-    UpgradeManager,
+    Upgrades\UpgradeManager,
     Utils\Util,
     Utils\File\Manager as FileManager,
     Utils\Config,
diff --git a/application/Espo/Core/Console/Commands/UpgradeStep.php b/application/Espo/Core/Console/Commands/UpgradeStep.php
index 7dd87930c3..203af03252 100644
--- a/application/Espo/Core/Console/Commands/UpgradeStep.php
+++ b/application/Espo/Core/Console/Commands/UpgradeStep.php
@@ -32,7 +32,7 @@ namespace Espo\Core\Console\Commands;
 use Espo\Core\{
     Container,
     Application,
-    UpgradeManager,
+    Upgrades\UpgradeManager,
     Console\Command,
     Console\Params,
     Console\IO,
diff --git a/application/Espo/Core/Upgrades/Actions/Extension/Install.php b/application/Espo/Core/Upgrades/Actions/Extension/Install.php
index 7e3022737c..7e60f3d905 100644
--- a/application/Espo/Core/Upgrades/Actions/Extension/Install.php
+++ b/application/Espo/Core/Upgrades/Actions/Extension/Install.php
@@ -29,7 +29,7 @@
 
 namespace Espo\Core\Upgrades\Actions\Extension;
 
-use Espo\Core\ExtensionManager;
+use Espo\Core\Upgrades\ExtensionManager;
 
 use Espo\Core\Utils\Util;
 
diff --git a/application/Espo/Core/ExtensionManager.php b/application/Espo/Core/Upgrades/ExtensionManager.php
similarity index 90%
rename from application/Espo/Core/ExtensionManager.php
rename to application/Espo/Core/Upgrades/ExtensionManager.php
index ce8272d444..6e63af703a 100644
--- a/application/Espo/Core/ExtensionManager.php
+++ b/application/Espo/Core/Upgrades/ExtensionManager.php
@@ -27,26 +27,25 @@
  * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
  ************************************************************************/
 
-namespace Espo\Core;
+namespace Espo\Core\Upgrades;
 
-class ExtensionManager extends Upgrades\Base
+class ExtensionManager extends Base
 {
     protected $name = 'Extension';
 
-    protected $params = array(
+    protected $params = [
         'packagePath' => 'data/upload/extensions',
         'backupPath' => 'data/.backup/extensions',
 
-        'scriptNames' => array(
+        'scriptNames' => [
             'before' => 'BeforeInstall',
             'after' => 'AfterInstall',
             'beforeUninstall' => 'BeforeUninstall',
             'afterUninstall' => 'AfterUninstall',
-        ),
-
-        'customDirNames' => array(
+        ],
+        'customDirNames' => [
             'before' => 'beforeInstallFiles',
             'after' => 'afterInstallFiles',
-        )
-    );
+        ],
+    ];
 }
diff --git a/application/Espo/Core/UpgradeManager.php b/application/Espo/Core/Upgrades/UpgradeManager.php
similarity index 94%
rename from application/Espo/Core/UpgradeManager.php
rename to application/Espo/Core/Upgrades/UpgradeManager.php
index c68617027b..8a3a51ab9b 100644
--- a/application/Espo/Core/UpgradeManager.php
+++ b/application/Espo/Core/Upgrades/UpgradeManager.php
@@ -27,11 +27,9 @@
  * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
  ************************************************************************/
 
-namespace Espo\Core;
+namespace Espo\Core\Upgrades;
 
-use Espo\Core\Exceptions\Error;
-
-class UpgradeManager extends Upgrades\Base
+class UpgradeManager extends Base
 {
     protected $name = 'Upgrade';
 
diff --git a/extension.php b/extension.php
index 3dd353eb9b..51b973747a 100644
--- a/extension.php
+++ b/extension.php
@@ -27,15 +27,20 @@
  * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
  ************************************************************************/
 
-if (substr(php_sapi_name(), 0, 3) != 'cli') exit;
+if (substr(php_sapi_name(), 0, 3) !== 'cli') {
+    exit;
+}
 
 include "bootstrap.php";
 
 use Espo\Core\{
     Application,
     ApplicationRunners\Rebuild,
+    Upgrades\ExtensionManager,
 };
 
+use Exception;
+
 $arg = isset($_SERVER['argv'][1]) ? trim($_SERVER['argv'][1]) : '';
 
 if (empty($arg)) {
@@ -47,6 +52,7 @@ if (!file_exists($arg)) {
 }
 
 $pathInfo = pathinfo($arg);
+
 if (!isset($pathInfo['extension']) || $pathInfo['extension'] !== 'zip' || !is_file($arg)) {
     die("Unsupported package.\n");
 }
@@ -57,7 +63,7 @@ $app->setupSystemUser();
 $config = $app->getContainer()->get('config');
 $entityManager = $app->getContainer()->get('entityManager');
 
-$upgradeManager = new \Espo\Core\ExtensionManager($app->getContainer());
+$upgradeManager = new ExtensionManager($app->getContainer());
 
 echo "Starting installation process...\n";
 
@@ -67,12 +73,14 @@ try {
 
     $upgradeId = $upgradeManager->upload($fileData);
     $upgradeManager->install(array('id' => $upgradeId));
-} catch (\Exception $e) {
+}
+catch (Exception $e) {
     die("Error: " . $e->getMessage() . "\n");
 }
 
 try {
     (new Application())->run(Rebuild::class);
-} catch (\Exception $e) {}
+}
+catch (Exception $e) {}
 
 echo "Extension installation is complete.\n";
diff --git a/tests/integration/Espo/Extension/GeneralTest.php b/tests/integration/Espo/Extension/GeneralTest.php
index 8743acb6e6..579eb1af14 100644
--- a/tests/integration/Espo/Extension/GeneralTest.php
+++ b/tests/integration/Espo/Extension/GeneralTest.php
@@ -29,11 +29,14 @@
 
 namespace tests\integration\Espo\Extension;
 
+use Espo\Core\Upgrades\ExtensionManager;
+
 class GeneralTest extends \tests\integration\Core\BaseTestCase
 {
     protected $dataFile = 'InitData.php';
 
     protected $userName = 'admin';
+
     protected $password = '1';
 
     protected $packagePath = 'Extension/General.zip';
@@ -48,7 +51,7 @@ class GeneralTest extends \tests\integration\Core\BaseTestCase
         $fileData = file_get_contents($this->normalizePath($this->packagePath));
         $fileData = 'data:application/zip;base64,' . base64_encode($fileData);
 
-        $extensionManager = new \Espo\Core\ExtensionManager($this->getContainer());
+        $extensionManager = new ExtensionManager($this->getContainer());
         $extensionId = $extensionManager->upload($fileData);
 
         $this->assertStringMatchesFormat('%x', $extensionId);
@@ -62,7 +65,7 @@ class GeneralTest extends \tests\integration\Core\BaseTestCase
     {
         $extensionId = $this->testUpload();
 
-        $extensionManager = new \Espo\Core\ExtensionManager($this->getContainer());
+        $extensionManager = new ExtensionManager($this->getContainer());
         $extensionManager->install(array('id' => $extensionId));
 
         $this->assertFileExists('data/upload/extensions/' . $extensionId . 'z');
@@ -85,7 +88,7 @@ class GeneralTest extends \tests\integration\Core\BaseTestCase
     {
         $extensionId = $this->testInstall();
 
-        $extensionManager = new \Espo\Core\ExtensionManager($this->getContainer());
+        $extensionManager = new ExtensionManager($this->getContainer());
         $extensionManager->uninstall(array('id' => $extensionId));
 
         $this->assertFileDoesNotExist('data/.backup/extensions/' . $extensionId); //directory
@@ -108,7 +111,7 @@ class GeneralTest extends \tests\integration\Core\BaseTestCase
     {
         $extensionId = $this->testUninstall();
 
-        $extensionManager = new \Espo\Core\ExtensionManager($this->getContainer());
+        $extensionManager = new ExtensionManager($this->getContainer());
         $extensionManager->delete(array('id' => $extensionId));
 
         $this->assertFileDoesNotExist('data/.backup/extensions/' . $extensionId); //directory
diff --git a/tests/integration/Espo/Upgrade/GeneralTest.php b/tests/integration/Espo/Upgrade/GeneralTest.php
index 89e7c91f82..cad96ad648 100644
--- a/tests/integration/Espo/Upgrade/GeneralTest.php
+++ b/tests/integration/Espo/Upgrade/GeneralTest.php
@@ -29,11 +29,14 @@
 
 namespace tests\integration\Espo\Upgrade;
 
+use Espo\Core\Upgrades\UpgradeManager;
+
 class GeneralTest extends \tests\integration\Core\BaseTestCase
 {
     protected $dataFile = 'InitData.php';
 
     protected $userName = 'admin';
+
     protected $password = '1';
 
     protected $packagePath = 'Upgrade/General.zip';
@@ -43,7 +46,7 @@ class GeneralTest extends \tests\integration\Core\BaseTestCase
         $fileData = file_get_contents($this->normalizePath($this->packagePath));
         $fileData = 'data:application/zip;base64,' . base64_encode($fileData);
 
-        $upgradeManager = new \Espo\Core\UpgradeManager($this->getContainer());
+        $upgradeManager = new UpgradeManager($this->getContainer());
         $upgradeId = $upgradeManager->upload($fileData);
 
         $this->assertStringMatchesFormat('%x', $upgradeId);
@@ -58,7 +61,8 @@ class GeneralTest extends \tests\integration\Core\BaseTestCase
     {
         $upgradeId = $this->testUpload();
 
-        $upgradeManager = new \Espo\Core\UpgradeManager($this->getContainer());
+        $upgradeManager = new UpgradeManager($this->getContainer());
+
         $upgradeManager->install(array('id' => $upgradeId));
 
         $this->assertFileDoesNotExist('data/upload/upgrades/' . $upgradeId . 'z');
@@ -79,7 +83,7 @@ class GeneralTest extends \tests\integration\Core\BaseTestCase
 
         $upgradeId = $this->testInstall();
 
-        $upgradeManager = new \Espo\Core\UpgradeManager($this->getContainer());
+        $upgradeManager = new UpgradeManager($this->getContainer());
         $upgradeManager->uninstall(array('id' => $upgradeId));
     }
 
@@ -89,7 +93,7 @@ class GeneralTest extends \tests\integration\Core\BaseTestCase
 
         $upgradeId = $this->testInstall();
 
-        $upgradeManager = new \Espo\Core\UpgradeManager($this->getContainer());
+        $upgradeManager = new UpgradeManager($this->getContainer());
         $upgradeManager->delete(array('id' => $upgradeId));
     }
 }
diff --git a/tests/unit/Espo/Core/Upgrades/ActionManagerTest.php b/tests/unit/Espo/Core/Upgrades/ActionManagerTest.php
index 271aaaba40..4f5de051c6 100644
--- a/tests/unit/Espo/Core/Upgrades/ActionManagerTest.php
+++ b/tests/unit/Espo/Core/Upgrades/ActionManagerTest.php
@@ -30,8 +30,8 @@
 namespace tests\unit\Espo\Core\Upgrades;
 
 use tests\unit\ReflectionHelper,
-    Espo\Core\ExtensionManager,
-    Espo\Core\UpgradeManager;
+    Espo\Core\Upgrades\ExtensionManager,
+    Espo\Core\Upgrades\UpgradeManager;
 
 use Espo\Core\Utils\File\Manager as FileManager;
 
diff --git a/upgrade.php b/upgrade.php
index c0fc40191c..6e95a7ced3 100644
--- a/upgrade.php
+++ b/upgrade.php
@@ -27,19 +27,25 @@
  * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
  ************************************************************************/
 
-if (substr(php_sapi_name(), 0, 3) != 'cli') exit;
+if (substr(php_sapi_name(), 0, 3) !== 'cli') {
+    exit;
+}
 
 include "bootstrap.php";
 
 use Espo\Core\{
     Application,
     ApplicationRunners\Rebuild,
+    Upgrades\UpgradeManager,
 };
 
+use Exception;
+
 $arg = isset($_SERVER['argv'][1]) ? trim($_SERVER['argv'][1]) : '';
 
 if ($arg == 'version' || $arg == '-v') {
-    $app = new \Espo\Core\Application();
+    $app = new Application();
+
     die("Current version is " . $app->getContainer()->get('config')->get('version') . ".\n");
 }
 
@@ -52,17 +58,19 @@ if (!file_exists($arg)) {
 }
 
 $pathInfo = pathinfo($arg);
+
 if (!isset($pathInfo['extension']) || $pathInfo['extension'] !== 'zip' || !is_file($arg)) {
     die("Unsupported package.\n");
 }
 
 $app = new Application();
+
 $app->setupSystemUser();
 
 $config = $app->getContainer()->get('config');
 $entityManager = $app->getContainer()->get('entityManager');
 
-$upgradeManager = new \Espo\Core\UpgradeManager($app->getContainer());
+$upgradeManager = new UpgradeManager($app->getContainer());
 
 echo "Current version is " . $config->get('version') . "\n";
 echo "Starting upgrade process...\n";
@@ -72,13 +80,16 @@ try {
     $fileData = 'data:application/zip;base64,' . base64_encode($fileData);
 
     $upgradeId = $upgradeManager->upload($fileData);
+
     $upgradeManager->install(['id' => $upgradeId]);
-} catch (\Exception $e) {
+}
+catch (Exception $e) {
     die("Error: " . $e->getMessage() . "\n");
 }
 
 try {
     (new Application())->run(Rebuild::class);
-} catch (\Exception $e) {}
+}
+catch (Exception $e) {}
 
 echo "Upgrade is complete. Current version is " . $config->get('version') . ". \n";