diff --git a/apps/advanced/tests/codeception/backend/_bootstrap.php b/apps/advanced/tests/codeception/backend/_bootstrap.php
index affe4081d8..69c38520d6 100644
--- a/apps/advanced/tests/codeception/backend/_bootstrap.php
+++ b/apps/advanced/tests/codeception/backend/_bootstrap.php
@@ -18,4 +18,4 @@ $_SERVER['SCRIPT_FILENAME'] = YII_TEST_BACKEND_ENTRY_FILE;
 $_SERVER['SCRIPT_NAME'] = YII_BACKEND_TEST_ENTRY_URL;
 $_SERVER['SERVER_NAME'] = 'localhost';
 
-Yii::setAlias('@codeception', dirname(__DIR__));
+Yii::setAlias('@tests', dirname(dirname(__DIR__)));
diff --git a/apps/advanced/tests/codeception/backend/acceptance.suite.yml b/apps/advanced/tests/codeception/backend/acceptance.suite.yml
index 0157530a2e..f93f392e24 100644
--- a/apps/advanced/tests/codeception/backend/acceptance.suite.yml
+++ b/apps/advanced/tests/codeception/backend/acceptance.suite.yml
@@ -12,7 +12,7 @@ class_name: AcceptanceTester
 modules:
     enabled:
         - PhpBrowser
-        - codeception\common\_support\FixtureHelper
+        - tests\codeception\common\_support\FixtureHelper
 # you can use WebDriver instead of PhpBrowser to test javascript and ajax.
 # This will require you to install selenium. See http://codeception.com/docs/04-AcceptanceTests#Selenium
 # "restart" option is used by the WebDriver to start each time per test-file new session and cookies,
diff --git a/apps/advanced/tests/codeception/backend/acceptance/LoginCept.php b/apps/advanced/tests/codeception/backend/acceptance/LoginCept.php
index e86b3f3713..bb6c65f80c 100644
--- a/apps/advanced/tests/codeception/backend/acceptance/LoginCept.php
+++ b/apps/advanced/tests/codeception/backend/acceptance/LoginCept.php
@@ -1,7 +1,7 @@
 <?php
 
-use codeception_backend\AcceptanceTester;
-use codeception\common\_pages\LoginPage;
+use tests\codeception\backend\AcceptanceTester;
+use tests\codeception\common\_pages\LoginPage;
 
 $I = new AcceptanceTester($scenario);
 $I->wantTo('ensure login page works');
diff --git a/apps/advanced/tests/codeception/backend/codeception.yml b/apps/advanced/tests/codeception/backend/codeception.yml
index 088fd21653..c16ac4765b 100644
--- a/apps/advanced/tests/codeception/backend/codeception.yml
+++ b/apps/advanced/tests/codeception/backend/codeception.yml
@@ -1,4 +1,4 @@
-namespace: codeception_backend
+namespace: tests\codeception\backend
 actor: Tester
 paths:
     tests: .
diff --git a/apps/advanced/tests/codeception/backend/functional.suite.yml b/apps/advanced/tests/codeception/backend/functional.suite.yml
index 8945473581..5bf5c8b7f5 100644
--- a/apps/advanced/tests/codeception/backend/functional.suite.yml
+++ b/apps/advanced/tests/codeception/backend/functional.suite.yml
@@ -11,7 +11,7 @@ modules:
     enabled:
       - Filesystem
       - Yii2
-      - codeception\common\_support\FixtureHelper
+      - tests\codeception\common\_support\FixtureHelper
     config:
         Yii2:
             configFile: '../config/backend/functional.php'
diff --git a/apps/advanced/tests/codeception/backend/functional/LoginCept.php b/apps/advanced/tests/codeception/backend/functional/LoginCept.php
index 4322258d88..3072d97521 100644
--- a/apps/advanced/tests/codeception/backend/functional/LoginCept.php
+++ b/apps/advanced/tests/codeception/backend/functional/LoginCept.php
@@ -1,7 +1,7 @@
 <?php
 
-use codeception_backend\FunctionalTester;
-use codeception\common\_pages\LoginPage;
+use tests\codeception\backend\FunctionalTester;
+use tests\codeception\common\_pages\LoginPage;
 
 $I = new FunctionalTester($scenario);
 $I->wantTo('ensure login page works');
diff --git a/apps/advanced/tests/codeception/backend/unit/DbTestCase.php b/apps/advanced/tests/codeception/backend/unit/DbTestCase.php
index 4f5a5fd352..35baef91be 100644
--- a/apps/advanced/tests/codeception/backend/unit/DbTestCase.php
+++ b/apps/advanced/tests/codeception/backend/unit/DbTestCase.php
@@ -4,5 +4,5 @@ namespace backend\tests\unit;
 
 class DbTestCase extends \yii\codeception\DbTestCase
 {
-    public $appConfig = '@codeception/config/backend/unit.php';
+    public $appConfig = '@tests/codeception/config/backend/unit.php';
 }
diff --git a/apps/advanced/tests/codeception/backend/unit/TestCase.php b/apps/advanced/tests/codeception/backend/unit/TestCase.php
index 5fd4fbc632..ad734d93ba 100644
--- a/apps/advanced/tests/codeception/backend/unit/TestCase.php
+++ b/apps/advanced/tests/codeception/backend/unit/TestCase.php
@@ -4,5 +4,5 @@ namespace backend\tests\unit;
 
 class TestCase extends \yii\codeception\TestCase
 {
-    public $appConfig = '@codeception/config/backend/unit.php';
+    public $appConfig = '@tests/codeception/config/backend/unit.php';
 }
diff --git a/apps/advanced/tests/codeception/common/_bootstrap.php b/apps/advanced/tests/codeception/common/_bootstrap.php
index b2d88d1e40..3e768208cc 100644
--- a/apps/advanced/tests/codeception/common/_bootstrap.php
+++ b/apps/advanced/tests/codeception/common/_bootstrap.php
@@ -11,4 +11,4 @@ require(YII_APP_BASE_PATH . '/common/config/aliases.php');
 // set correct script paths
 $_SERVER['SERVER_NAME'] = 'localhost';
 
-Yii::setAlias('@codeception', dirname(__DIR__));
\ No newline at end of file
+Yii::setAlias('@tests', dirname(dirname(__DIR__)));
\ No newline at end of file
diff --git a/apps/advanced/tests/codeception/common/_pages/LoginPage.php b/apps/advanced/tests/codeception/common/_pages/LoginPage.php
index 7f93ed0633..6a1dc84337 100644
--- a/apps/advanced/tests/codeception/common/_pages/LoginPage.php
+++ b/apps/advanced/tests/codeception/common/_pages/LoginPage.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace codeception\common\_pages;
+namespace tests\codeception\common\_pages;
 
 use yii\codeception\BasePage;
 
diff --git a/apps/advanced/tests/codeception/common/_support/FixtureHelper.php b/apps/advanced/tests/codeception/common/_support/FixtureHelper.php
index 22c485759c..cc2a3112b2 100644
--- a/apps/advanced/tests/codeception/common/_support/FixtureHelper.php
+++ b/apps/advanced/tests/codeception/common/_support/FixtureHelper.php
@@ -1,8 +1,8 @@
 <?php
 
-namespace codeception\common\_support;
+namespace tests\codeception\common\_support;
 
-use codeception\common\fixtures\UserFixture;
+use tests\codeception\common\fixtures\UserFixture;
 use Codeception\Module;
 use yii\test\FixtureTrait;
 
@@ -53,7 +53,7 @@ class FixtureHelper extends Module
         return [
             'user' => [
                 'class' => UserFixture::className(),
-                'dataFile' => '@codeception/common/fixtures/data/init_login.php',
+                'dataFile' => '@tests/codeception/common/fixtures/data/init_login.php',
             ],
         ];
     }
diff --git a/apps/advanced/tests/codeception/common/codeception.yml b/apps/advanced/tests/codeception/common/codeception.yml
index 935e97c261..e8a3407a48 100644
--- a/apps/advanced/tests/codeception/common/codeception.yml
+++ b/apps/advanced/tests/codeception/common/codeception.yml
@@ -1,4 +1,4 @@
-namespace: codeception_common
+namespace: tests\codeception\common
 actor: Tester
 paths:
     tests: .
diff --git a/apps/advanced/tests/codeception/common/fixtures/UserFixture.php b/apps/advanced/tests/codeception/common/fixtures/UserFixture.php
index db5e0d19a5..7153c8c0b3 100644
--- a/apps/advanced/tests/codeception/common/fixtures/UserFixture.php
+++ b/apps/advanced/tests/codeception/common/fixtures/UserFixture.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace codeception\common\fixtures;
+namespace tests\codeception\common\fixtures;
 
 use yii\test\ActiveFixture;
 
diff --git a/apps/advanced/tests/codeception/common/unit/DbTestCase.php b/apps/advanced/tests/codeception/common/unit/DbTestCase.php
index b4bd51f124..2159a69caa 100644
--- a/apps/advanced/tests/codeception/common/unit/DbTestCase.php
+++ b/apps/advanced/tests/codeception/common/unit/DbTestCase.php
@@ -1,11 +1,11 @@
 <?php
 
-namespace codeception\common\unit;
+namespace tests\codeception\common\unit;
 
 /**
  * @inheritdoc
  */
 class DbTestCase extends \yii\codeception\DbTestCase
 {
-    public $appConfig = '@codeception/config/common/unit.php';
+    public $appConfig = '@tests/codeception/config/common/unit.php';
 }
diff --git a/apps/advanced/tests/codeception/common/unit/TestCase.php b/apps/advanced/tests/codeception/common/unit/TestCase.php
index e37282dea1..73047580b1 100644
--- a/apps/advanced/tests/codeception/common/unit/TestCase.php
+++ b/apps/advanced/tests/codeception/common/unit/TestCase.php
@@ -1,11 +1,11 @@
 <?php
 
-namespace common\tests\unit;
+namespace tests\codeception\common\unit;
 
 /**
  * @inheritdoc
  */
 class TestCase extends \yii\codeception\TestCase
 {
-    public $appConfig = '@codeception/config/common/unit.php';
+    public $appConfig = '@tests/codeception/config/common/unit.php';
 }
diff --git a/apps/advanced/tests/codeception/common/unit/models/LoginFormTest.php b/apps/advanced/tests/codeception/common/unit/models/LoginFormTest.php
index 847b8df95f..7fd64f6582 100644
--- a/apps/advanced/tests/codeception/common/unit/models/LoginFormTest.php
+++ b/apps/advanced/tests/codeception/common/unit/models/LoginFormTest.php
@@ -1,12 +1,12 @@
 <?php
 
-namespace codeception\common\unit\models;
+namespace tests\codeception\common\unit\models;
 
 use Yii;
-use codeception\common\unit\DbTestCase;
+use tests\codeception\common\unit\DbTestCase;
 use Codeception\Specify;
 use common\models\LoginForm;
-use codeception\common\fixtures\UserFixture;
+use tests\codeception\common\fixtures\UserFixture;
 
 /**
  * Login form test
@@ -86,7 +86,7 @@ class LoginFormTest extends DbTestCase
         return [
             'user' => [
                 'class' => UserFixture::className(),
-                'dataFile' => '@codeception/common/unit/fixtures/data/models/user.php'
+                'dataFile' => '@tests/codeception/common/unit/fixtures/data/models/user.php'
             ],
         ];
     }
diff --git a/apps/advanced/tests/codeception/console/_bootstrap.php b/apps/advanced/tests/codeception/console/_bootstrap.php
index b2d88d1e40..3e768208cc 100644
--- a/apps/advanced/tests/codeception/console/_bootstrap.php
+++ b/apps/advanced/tests/codeception/console/_bootstrap.php
@@ -11,4 +11,4 @@ require(YII_APP_BASE_PATH . '/common/config/aliases.php');
 // set correct script paths
 $_SERVER['SERVER_NAME'] = 'localhost';
 
-Yii::setAlias('@codeception', dirname(__DIR__));
\ No newline at end of file
+Yii::setAlias('@tests', dirname(dirname(__DIR__)));
\ No newline at end of file
diff --git a/apps/advanced/tests/codeception/console/codeception.yml b/apps/advanced/tests/codeception/console/codeception.yml
index 41b31f6281..d1ae79465f 100644
--- a/apps/advanced/tests/codeception/console/codeception.yml
+++ b/apps/advanced/tests/codeception/console/codeception.yml
@@ -1,4 +1,4 @@
-namespace: codeception_console
+namespace: tests\codeception\console
 actor: Tester
 paths:
     tests: .
diff --git a/apps/advanced/tests/codeception/console/unit/DbTestCase.php b/apps/advanced/tests/codeception/console/unit/DbTestCase.php
index 0d8e56e8b6..d74860dee8 100644
--- a/apps/advanced/tests/codeception/console/unit/DbTestCase.php
+++ b/apps/advanced/tests/codeception/console/unit/DbTestCase.php
@@ -1,11 +1,11 @@
 <?php
 
-namespace console\tests\unit;
+namespace tests\codeception\console\unit;
 
 /**
  * @inheritdoc
  */
 class DbTestCase extends \yii\codeception\DbTestCase
 {
-    public $appConfig = '@codeception/config/console/config.php';
+    public $appConfig = '@tests/codeception/config/console/config.php';
 }
diff --git a/apps/advanced/tests/codeception/console/unit/TestCase.php b/apps/advanced/tests/codeception/console/unit/TestCase.php
index 8bfc7adf54..50761b34ef 100644
--- a/apps/advanced/tests/codeception/console/unit/TestCase.php
+++ b/apps/advanced/tests/codeception/console/unit/TestCase.php
@@ -1,11 +1,11 @@
 <?php
 
-namespace console\tests\unit;
+namespace tests\codeception\console\unit;
 
 /**
  * @inheritdoc
  */
 class TestCase extends \yii\codeception\TestCase
 {
-    public $appConfig = '@codeception/config/console/config.php';
+    public $appConfig = '@tests/codeception/config/console/config.php';
 }
diff --git a/apps/advanced/tests/codeception/frontend/_bootstrap.php b/apps/advanced/tests/codeception/frontend/_bootstrap.php
index dd01f828cc..06bfd20181 100644
--- a/apps/advanced/tests/codeception/frontend/_bootstrap.php
+++ b/apps/advanced/tests/codeception/frontend/_bootstrap.php
@@ -18,4 +18,4 @@ $_SERVER['SCRIPT_FILENAME'] = FRONTEND_ENTRY_FILE;
 $_SERVER['SCRIPT_NAME'] = FRONTEND_ENTRY_URL;
 $_SERVER['SERVER_NAME'] = 'localhost';
 
-Yii::setAlias('@codeception', dirname(__DIR__));
\ No newline at end of file
+Yii::setAlias('@tests', dirname(dirname(__DIR__)));
\ No newline at end of file
diff --git a/apps/advanced/tests/codeception/frontend/_pages/AboutPage.php b/apps/advanced/tests/codeception/frontend/_pages/AboutPage.php
index d752edc0c9..6f04ea0e30 100644
--- a/apps/advanced/tests/codeception/frontend/_pages/AboutPage.php
+++ b/apps/advanced/tests/codeception/frontend/_pages/AboutPage.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace codeception\frontend\_pages;
+namespace tests\codeception\frontend\_pages;
 
 use yii\codeception\BasePage;
 
diff --git a/apps/advanced/tests/codeception/frontend/_pages/ContactPage.php b/apps/advanced/tests/codeception/frontend/_pages/ContactPage.php
index 986e371088..715a2ee4a0 100644
--- a/apps/advanced/tests/codeception/frontend/_pages/ContactPage.php
+++ b/apps/advanced/tests/codeception/frontend/_pages/ContactPage.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace codeception\frontend\_pages;
+namespace tests\codeception\frontend\_pages;
 
 use yii\codeception\BasePage;
 
diff --git a/apps/advanced/tests/codeception/frontend/_pages/SignupPage.php b/apps/advanced/tests/codeception/frontend/_pages/SignupPage.php
index 49bdcf9d43..0e1cefa94c 100644
--- a/apps/advanced/tests/codeception/frontend/_pages/SignupPage.php
+++ b/apps/advanced/tests/codeception/frontend/_pages/SignupPage.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace codeception\frontend\_pages;
+namespace tests\codeception\frontend\_pages;
 
 use \yii\codeception\BasePage;
 
diff --git a/apps/advanced/tests/codeception/frontend/acceptance.suite.yml b/apps/advanced/tests/codeception/frontend/acceptance.suite.yml
index 0157530a2e..f93f392e24 100644
--- a/apps/advanced/tests/codeception/frontend/acceptance.suite.yml
+++ b/apps/advanced/tests/codeception/frontend/acceptance.suite.yml
@@ -12,7 +12,7 @@ class_name: AcceptanceTester
 modules:
     enabled:
         - PhpBrowser
-        - codeception\common\_support\FixtureHelper
+        - tests\codeception\common\_support\FixtureHelper
 # you can use WebDriver instead of PhpBrowser to test javascript and ajax.
 # This will require you to install selenium. See http://codeception.com/docs/04-AcceptanceTests#Selenium
 # "restart" option is used by the WebDriver to start each time per test-file new session and cookies,
diff --git a/apps/advanced/tests/codeception/frontend/acceptance/AboutCept.php b/apps/advanced/tests/codeception/frontend/acceptance/AboutCept.php
index c52234f1f8..7f7f97e318 100644
--- a/apps/advanced/tests/codeception/frontend/acceptance/AboutCept.php
+++ b/apps/advanced/tests/codeception/frontend/acceptance/AboutCept.php
@@ -1,6 +1,6 @@
 <?php
-use codeception_frontend\AcceptanceTester;
-use codeception\frontend\_pages\AboutPage;
+use tests\codeception\frontend\AcceptanceTester;
+use tests\codeception\frontend\_pages\AboutPage;
 
 $I = new AcceptanceTester($scenario);
 $I->wantTo('ensure that about works');
diff --git a/apps/advanced/tests/codeception/frontend/acceptance/ContactCept.php b/apps/advanced/tests/codeception/frontend/acceptance/ContactCept.php
index c80469ee9c..c537fd4807 100644
--- a/apps/advanced/tests/codeception/frontend/acceptance/ContactCept.php
+++ b/apps/advanced/tests/codeception/frontend/acceptance/ContactCept.php
@@ -1,6 +1,6 @@
 <?php
-use codeception_frontend\AcceptanceTester;
-use codeception\frontend\_pages\ContactPage;
+use tests\codeception\frontend\AcceptanceTester;
+use tests\codeception\frontend\_pages\ContactPage;
 
 $I = new AcceptanceTester($scenario);
 $I->wantTo('ensure that contact works');
diff --git a/apps/advanced/tests/codeception/frontend/acceptance/HomeCept.php b/apps/advanced/tests/codeception/frontend/acceptance/HomeCept.php
index efbcddbb86..5cf837916f 100644
--- a/apps/advanced/tests/codeception/frontend/acceptance/HomeCept.php
+++ b/apps/advanced/tests/codeception/frontend/acceptance/HomeCept.php
@@ -1,5 +1,5 @@
 <?php
-use codeception_frontend\AcceptanceTester;
+use tests\codeception\frontend\AcceptanceTester;
 
 $I = new AcceptanceTester($scenario);
 $I->wantTo('ensure that home page works');
diff --git a/apps/advanced/tests/codeception/frontend/acceptance/LoginCept.php b/apps/advanced/tests/codeception/frontend/acceptance/LoginCept.php
index cc8411d8de..e4363a837d 100644
--- a/apps/advanced/tests/codeception/frontend/acceptance/LoginCept.php
+++ b/apps/advanced/tests/codeception/frontend/acceptance/LoginCept.php
@@ -1,6 +1,6 @@
 <?php
-use codeception_frontend\AcceptanceTester;
-use codeception\common\_pages\LoginPage;
+use tests\codeception\frontend\AcceptanceTester;
+use tests\codeception\common\_pages\LoginPage;
 
 $I = new AcceptanceTester($scenario);
 $I->wantTo('ensure login page works');
diff --git a/apps/advanced/tests/codeception/frontend/acceptance/SignupCest.php b/apps/advanced/tests/codeception/frontend/acceptance/SignupCest.php
index 9b86b953ab..ab4b7bba28 100644
--- a/apps/advanced/tests/codeception/frontend/acceptance/SignupCest.php
+++ b/apps/advanced/tests/codeception/frontend/acceptance/SignupCest.php
@@ -1,8 +1,8 @@
 <?php
 
-namespace codeception\frontend\acceptance;
+namespace tests\codeception\frontend\acceptance;
 
-use codeception\frontend\_pages\SignupPage;
+use tests\codeception\frontend\_pages\SignupPage;
 use common\models\User;
 
 class SignupCest
diff --git a/apps/advanced/tests/codeception/frontend/codeception.yml b/apps/advanced/tests/codeception/frontend/codeception.yml
index cbd5b75d3b..996c70acf8 100644
--- a/apps/advanced/tests/codeception/frontend/codeception.yml
+++ b/apps/advanced/tests/codeception/frontend/codeception.yml
@@ -1,4 +1,4 @@
-namespace: codeception_frontend
+namespace: tests\codeception\frontend
 actor: Tester
 paths:
     tests: .
diff --git a/apps/advanced/tests/codeception/frontend/functional.suite.yml b/apps/advanced/tests/codeception/frontend/functional.suite.yml
index 632ed37bed..5372b0d68c 100644
--- a/apps/advanced/tests/codeception/frontend/functional.suite.yml
+++ b/apps/advanced/tests/codeception/frontend/functional.suite.yml
@@ -11,7 +11,7 @@ modules:
     enabled:
       - Filesystem
       - Yii2
-      - codeception\common\_support\FixtureHelper
+      - tests\codeception\common\_support\FixtureHelper
     config:
         Yii2:
             configFile: '../config/frontend/functional.php'
diff --git a/apps/advanced/tests/codeception/frontend/functional/AboutCept.php b/apps/advanced/tests/codeception/frontend/functional/AboutCept.php
index 158e4fa0e5..bc6459061c 100644
--- a/apps/advanced/tests/codeception/frontend/functional/AboutCept.php
+++ b/apps/advanced/tests/codeception/frontend/functional/AboutCept.php
@@ -1,6 +1,6 @@
 <?php
-use codeception_frontend\FunctionalTester;
-use codeception\frontend\_pages\AboutPage;
+use tests\codeception\frontend\FunctionalTester;
+use tests\codeception\frontend\_pages\AboutPage;
 
 $I = new FunctionalTester($scenario);
 $I->wantTo('ensure that about works');
diff --git a/apps/advanced/tests/codeception/frontend/functional/ContactCept.php b/apps/advanced/tests/codeception/frontend/functional/ContactCept.php
index 9630b0de83..1aaac3f5a1 100644
--- a/apps/advanced/tests/codeception/frontend/functional/ContactCept.php
+++ b/apps/advanced/tests/codeception/frontend/functional/ContactCept.php
@@ -1,6 +1,6 @@
 <?php
-use codeception_frontend\FunctionalTester;
-use codeception\frontend\_pages\ContactPage;
+use tests\codeception\frontend\FunctionalTester;
+use tests\codeception\frontend\_pages\ContactPage;
 
 $I = new FunctionalTester($scenario);
 $I->wantTo('ensure that contact works');
diff --git a/apps/advanced/tests/codeception/frontend/functional/HomeCept.php b/apps/advanced/tests/codeception/frontend/functional/HomeCept.php
index c250e43402..0f5b2ffbb9 100644
--- a/apps/advanced/tests/codeception/frontend/functional/HomeCept.php
+++ b/apps/advanced/tests/codeception/frontend/functional/HomeCept.php
@@ -1,5 +1,5 @@
 <?php
-use codeception_frontend\FunctionalTester;
+use tests\codeception\frontend\FunctionalTester;
 $I = new FunctionalTester($scenario);
 $I->wantTo('ensure that home page works');
 $I->amOnPage(Yii::$app->homeUrl);
diff --git a/apps/advanced/tests/codeception/frontend/functional/LoginCept.php b/apps/advanced/tests/codeception/frontend/functional/LoginCept.php
index c5d94afa59..0fb3477614 100644
--- a/apps/advanced/tests/codeception/frontend/functional/LoginCept.php
+++ b/apps/advanced/tests/codeception/frontend/functional/LoginCept.php
@@ -1,6 +1,6 @@
 <?php
-use codeception_frontend\FunctionalTester;
-use codeception\common\_pages\LoginPage;
+use tests\codeception\frontend\FunctionalTester;
+use tests\codeception\common\_pages\LoginPage;
 
 $I = new FunctionalTester($scenario);
 $I->wantTo('ensure login page works');
diff --git a/apps/advanced/tests/codeception/frontend/functional/SignupCest.php b/apps/advanced/tests/codeception/frontend/functional/SignupCest.php
index 0ed81b7a22..525b0373fa 100644
--- a/apps/advanced/tests/codeception/frontend/functional/SignupCest.php
+++ b/apps/advanced/tests/codeception/frontend/functional/SignupCest.php
@@ -1,8 +1,8 @@
 <?php
 
-namespace codeception\frontend\functional;
+namespace tests\codeception\frontend\functional;
 
-use codeception\frontend\_pages\SignupPage;
+use tests\codeception\frontend\_pages\SignupPage;
 use common\models\User;
 
 class SignupCest
diff --git a/apps/advanced/tests/codeception/frontend/unit/DbTestCase.php b/apps/advanced/tests/codeception/frontend/unit/DbTestCase.php
index 70b350c628..2b2ba8b1eb 100644
--- a/apps/advanced/tests/codeception/frontend/unit/DbTestCase.php
+++ b/apps/advanced/tests/codeception/frontend/unit/DbTestCase.php
@@ -1,11 +1,11 @@
 <?php
 
-namespace codeception\frontend\unit;
+namespace tests\codeception\frontend\unit;
 
 /**
  * @inheritdoc
  */
 class DbTestCase extends \yii\codeception\DbTestCase
 {
-    public $appConfig = '@codeception/config/frontend/unit.php';
+    public $appConfig = '@tests/codeception/config/frontend/unit.php';
 }
diff --git a/apps/advanced/tests/codeception/frontend/unit/TestCase.php b/apps/advanced/tests/codeception/frontend/unit/TestCase.php
index 1a0c659093..3ccaa3cb51 100644
--- a/apps/advanced/tests/codeception/frontend/unit/TestCase.php
+++ b/apps/advanced/tests/codeception/frontend/unit/TestCase.php
@@ -1,11 +1,11 @@
 <?php
 
-namespace codeception\frontend\unit;
+namespace tests\codeception\frontend\unit;
 
 /**
  * @inheritdoc
  */
 class TestCase extends \yii\codeception\TestCase
 {
-    public $appConfig = '@codeception/config/frontend/unit.php';
+    public $appConfig = '@tests/codeception/config/frontend/unit.php';
 }
diff --git a/apps/advanced/tests/codeception/frontend/unit/models/ContactFormTest.php b/apps/advanced/tests/codeception/frontend/unit/models/ContactFormTest.php
index f2781a2e6a..9aaf595f8b 100644
--- a/apps/advanced/tests/codeception/frontend/unit/models/ContactFormTest.php
+++ b/apps/advanced/tests/codeception/frontend/unit/models/ContactFormTest.php
@@ -1,9 +1,9 @@
 <?php
 
-namespace codeception\frontend\unit\models;
+namespace tests\codeception\frontend\unit\models;
 
 use Yii;
-use codeception\frontend\unit\TestCase;
+use tests\codeception\frontend\unit\TestCase;
 use frontend\models\ContactForm;
 
 class ContactFormTest extends TestCase
diff --git a/apps/advanced/tests/codeception/frontend/unit/models/PasswordResetRequestFormTest.php b/apps/advanced/tests/codeception/frontend/unit/models/PasswordResetRequestFormTest.php
index f0843fa5fd..ec65a0eae3 100644
--- a/apps/advanced/tests/codeception/frontend/unit/models/PasswordResetRequestFormTest.php
+++ b/apps/advanced/tests/codeception/frontend/unit/models/PasswordResetRequestFormTest.php
@@ -1,11 +1,11 @@
 <?php
 
-namespace codeception\frontend\tests\models;
+namespace tests\codeception\frontend\models;
 
 use Yii;
-use codeception\frontend\unit\DbTestCase;
+use tests\codeception\frontend\unit\DbTestCase;
 use frontend\models\PasswordResetRequestForm;
-use codeception\common\fixtures\UserFixture;
+use tests\codeception\common\fixtures\UserFixture;
 use common\models\User;
 use Codeception\Specify;
 
@@ -75,7 +75,7 @@ class PasswordResetRequestFormTest extends DbTestCase
         return [
             'user' => [
                 'class' => UserFixture::className(),
-                'dataFile' => '@codeception/frontend/unit/fixtures/data/models/user.php'
+                'dataFile' => '@tests/codeception/frontend/unit/fixtures/data/models/user.php'
             ],
         ];
     }
diff --git a/apps/advanced/tests/codeception/frontend/unit/models/ResetPasswordFormTest.php b/apps/advanced/tests/codeception/frontend/unit/models/ResetPasswordFormTest.php
index 1997b2f4f7..a2f5012400 100644
--- a/apps/advanced/tests/codeception/frontend/unit/models/ResetPasswordFormTest.php
+++ b/apps/advanced/tests/codeception/frontend/unit/models/ResetPasswordFormTest.php
@@ -1,9 +1,9 @@
 <?php
 
-namespace codeception\frontend\unit\models;
+namespace tests\codeception\frontend\unit\models;
 
-use codeception\frontend\unit\DbTestCase;
-use codeception\common\fixtures\UserFixture;
+use tests\codeception\frontend\unit\DbTestCase;
+use tests\codeception\common\fixtures\UserFixture;
 use frontend\models\ResetPasswordForm;
 
 class ResetPasswordFormTest extends DbTestCase
@@ -36,7 +36,7 @@ class ResetPasswordFormTest extends DbTestCase
         return [
             'user' => [
                 'class' => UserFixture::className(),
-                'dataFile' => '@codeception/frontend/unit/fixtures/data/models/user.php'
+                'dataFile' => '@tests/codeception/frontend/unit/fixtures/data/models/user.php'
             ],
         ];
     }
diff --git a/apps/advanced/tests/codeception/frontend/unit/models/SignupFormTest.php b/apps/advanced/tests/codeception/frontend/unit/models/SignupFormTest.php
index ff8b56d288..4d869f1122 100644
--- a/apps/advanced/tests/codeception/frontend/unit/models/SignupFormTest.php
+++ b/apps/advanced/tests/codeception/frontend/unit/models/SignupFormTest.php
@@ -1,9 +1,9 @@
 <?php
 
-namespace codeception\frontend\unit\models;
+namespace tests\codeception\frontend\unit\models;
 
-use codeception\frontend\unit\DbTestCase;
-use codeception\common\fixtures\UserFixture;
+use tests\codeception\frontend\unit\DbTestCase;
+use tests\codeception\common\fixtures\UserFixture;
 use Codeception\Specify;
 use frontend\models\SignupForm;
 
@@ -45,7 +45,7 @@ class SignupFormTest extends DbTestCase
         return [
             'user' => [
                 'class' => UserFixture::className(),
-                'dataFile' => '@codeception/frontend/unit/fixtures/data/models/user.php',
+                'dataFile' => '@tests/codeception/frontend/unit/fixtures/data/models/user.php',
             ],
         ];
     }
diff --git a/apps/basic/tests/codeception/_bootstrap.php b/apps/basic/tests/codeception/_bootstrap.php
index 5f5ae10b42..9855939782 100644
--- a/apps/basic/tests/codeception/_bootstrap.php
+++ b/apps/basic/tests/codeception/_bootstrap.php
@@ -12,4 +12,4 @@ $_SERVER['SCRIPT_FILENAME'] = YII_TEST_ENTRY_FILE;
 $_SERVER['SCRIPT_NAME'] = YII_TEST_ENTRY_URL;
 $_SERVER['SERVER_NAME'] = 'localhost';
 
-Yii::setAlias('@codeception', __DIR__);
+Yii::setAlias('@tests', dirname(__DIR__));
diff --git a/apps/basic/tests/codeception/_pages/AboutPage.php b/apps/basic/tests/codeception/_pages/AboutPage.php
index b6ca34a293..b56320d093 100644
--- a/apps/basic/tests/codeception/_pages/AboutPage.php
+++ b/apps/basic/tests/codeception/_pages/AboutPage.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace codeception\_pages;
+namespace tests\codeception\_pages;
 
 use yii\codeception\BasePage;
 
diff --git a/apps/basic/tests/codeception/_pages/ContactPage.php b/apps/basic/tests/codeception/_pages/ContactPage.php
index 9561255946..5701e2cb4d 100644
--- a/apps/basic/tests/codeception/_pages/ContactPage.php
+++ b/apps/basic/tests/codeception/_pages/ContactPage.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace codeception\_pages;
+namespace tests\codeception\_pages;
 
 use yii\codeception\BasePage;
 
diff --git a/apps/basic/tests/codeception/_pages/LoginPage.php b/apps/basic/tests/codeception/_pages/LoginPage.php
index af10049630..c3a2ef2dd7 100644
--- a/apps/basic/tests/codeception/_pages/LoginPage.php
+++ b/apps/basic/tests/codeception/_pages/LoginPage.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace codeception\_pages;
+namespace tests\codeception\_pages;
 
 use yii\codeception\BasePage;
 
diff --git a/apps/basic/tests/codeception/acceptance/AboutCept.php b/apps/basic/tests/codeception/acceptance/AboutCept.php
index 2dcc6a13b1..1ef220ebe2 100644
--- a/apps/basic/tests/codeception/acceptance/AboutCept.php
+++ b/apps/basic/tests/codeception/acceptance/AboutCept.php
@@ -1,6 +1,6 @@
 <?php
 
-use codeception\_pages\AboutPage;
+use tests\codeception\_pages\AboutPage;
 
 $I = new AcceptanceTester($scenario);
 $I->wantTo('ensure that about works');
diff --git a/apps/basic/tests/codeception/acceptance/ContactCept.php b/apps/basic/tests/codeception/acceptance/ContactCept.php
index c9adc7e15e..98ba2ef12c 100644
--- a/apps/basic/tests/codeception/acceptance/ContactCept.php
+++ b/apps/basic/tests/codeception/acceptance/ContactCept.php
@@ -1,6 +1,6 @@
 <?php
 
-use codeception\_pages\ContactPage;
+use tests\codeception\_pages\ContactPage;
 
 $I = new AcceptanceTester($scenario);
 $I->wantTo('ensure that contact works');
diff --git a/apps/basic/tests/codeception/acceptance/LoginCept.php b/apps/basic/tests/codeception/acceptance/LoginCept.php
index 6d07c08958..4f022e1c28 100644
--- a/apps/basic/tests/codeception/acceptance/LoginCept.php
+++ b/apps/basic/tests/codeception/acceptance/LoginCept.php
@@ -1,6 +1,6 @@
 <?php
 
-use codeception\_pages\LoginPage;
+use tests\codeception\_pages\LoginPage;
 
 $I = new AcceptanceTester($scenario);
 $I->wantTo('ensure that login works');
diff --git a/apps/basic/tests/codeception/functional/AboutCept.php b/apps/basic/tests/codeception/functional/AboutCept.php
index 3edd61da31..ae7b45b308 100644
--- a/apps/basic/tests/codeception/functional/AboutCept.php
+++ b/apps/basic/tests/codeception/functional/AboutCept.php
@@ -1,6 +1,6 @@
 <?php
 
-use codeception\_pages\AboutPage;
+use tests\codeception\_pages\AboutPage;
 
 $I = new FunctionalTester($scenario);
 $I->wantTo('ensure that about works');
diff --git a/apps/basic/tests/codeception/functional/ContactCept.php b/apps/basic/tests/codeception/functional/ContactCept.php
index c5e83b4f19..47604058d7 100644
--- a/apps/basic/tests/codeception/functional/ContactCept.php
+++ b/apps/basic/tests/codeception/functional/ContactCept.php
@@ -1,6 +1,6 @@
 <?php
 
-use codeception\_pages\ContactPage;
+use tests\codeception\_pages\ContactPage;
 
 $I = new FunctionalTester($scenario);
 $I->wantTo('ensure that contact works');
diff --git a/apps/basic/tests/codeception/functional/LoginCept.php b/apps/basic/tests/codeception/functional/LoginCept.php
index 4cb283ac97..991d27c3c9 100644
--- a/apps/basic/tests/codeception/functional/LoginCept.php
+++ b/apps/basic/tests/codeception/functional/LoginCept.php
@@ -1,6 +1,6 @@
 <?php
 
-use codeception\_pages\LoginPage;
+use tests\codeception\_pages\LoginPage;
 
 $I = new FunctionalTester($scenario);
 $I->wantTo('ensure that login works');
diff --git a/apps/basic/tests/codeception/unit/models/ContactFormTest.php b/apps/basic/tests/codeception/unit/models/ContactFormTest.php
index 8adda18c61..3234829432 100644
--- a/apps/basic/tests/codeception/unit/models/ContactFormTest.php
+++ b/apps/basic/tests/codeception/unit/models/ContactFormTest.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace codeception\unit\models;
+namespace tests\codeception\unit\models;
 
 use Yii;
 use yii\codeception\TestCase;
diff --git a/apps/basic/tests/codeception/unit/models/LoginFormTest.php b/apps/basic/tests/codeception/unit/models/LoginFormTest.php
index 5e67624648..c7f971a06f 100644
--- a/apps/basic/tests/codeception/unit/models/LoginFormTest.php
+++ b/apps/basic/tests/codeception/unit/models/LoginFormTest.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace codeception\unit\models;
+namespace tests\codeception\unit\models;
 
 use Yii;
 use yii\codeception\TestCase;
diff --git a/apps/basic/tests/codeception/unit/models/UserTest.php b/apps/basic/tests/codeception/unit/models/UserTest.php
index 01fde74cb7..f4f4f4bb9b 100644
--- a/apps/basic/tests/codeception/unit/models/UserTest.php
+++ b/apps/basic/tests/codeception/unit/models/UserTest.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace codeception\unit\models;
+namespace tests\codeception\unit\models;
 
 use yii\codeception\TestCase;
 
diff --git a/extensions/codeception/TestCase.php b/extensions/codeception/TestCase.php
index 1d331d82a4..a810cb6e51 100644
--- a/extensions/codeception/TestCase.php
+++ b/extensions/codeception/TestCase.php
@@ -31,7 +31,7 @@ class TestCase extends Test
      * The application configuration array may contain an optional `class` element which specifies the class
      * name of the application instance to be created. By default, a [[\yii\web\Application]] instance will be created.
      */
-    public $appConfig = '@codeception/config/unit.php';
+    public $appConfig = '@tests/codeception/config/unit.php';
 
 
     /**