diff --git a/composer.json b/composer.json
index 0465796..341bc94 100644
--- a/composer.json
+++ b/composer.json
@@ -43,7 +43,7 @@
     ],
     "autoload": {
         "psr-4": {
-            "yii\\bootstrap\\": ""
+            "yii\\bootstrap\\": "src"
         }
     },
     "extra": {
diff --git a/ActiveField.php b/src/ActiveField.php
similarity index 100%
rename from ActiveField.php
rename to src/ActiveField.php
diff --git a/ActiveForm.php b/src/ActiveForm.php
similarity index 100%
rename from ActiveForm.php
rename to src/ActiveForm.php
diff --git a/Alert.php b/src/Alert.php
similarity index 100%
rename from Alert.php
rename to src/Alert.php
diff --git a/BaseHtml.php b/src/BaseHtml.php
similarity index 100%
rename from BaseHtml.php
rename to src/BaseHtml.php
diff --git a/BootstrapAsset.php b/src/BootstrapAsset.php
similarity index 100%
rename from BootstrapAsset.php
rename to src/BootstrapAsset.php
diff --git a/BootstrapPluginAsset.php b/src/BootstrapPluginAsset.php
similarity index 100%
rename from BootstrapPluginAsset.php
rename to src/BootstrapPluginAsset.php
diff --git a/BootstrapThemeAsset.php b/src/BootstrapThemeAsset.php
similarity index 100%
rename from BootstrapThemeAsset.php
rename to src/BootstrapThemeAsset.php
diff --git a/BootstrapWidgetTrait.php b/src/BootstrapWidgetTrait.php
similarity index 100%
rename from BootstrapWidgetTrait.php
rename to src/BootstrapWidgetTrait.php
diff --git a/Button.php b/src/Button.php
similarity index 100%
rename from Button.php
rename to src/Button.php
diff --git a/ButtonDropdown.php b/src/ButtonDropdown.php
similarity index 100%
rename from ButtonDropdown.php
rename to src/ButtonDropdown.php
diff --git a/ButtonGroup.php b/src/ButtonGroup.php
similarity index 100%
rename from ButtonGroup.php
rename to src/ButtonGroup.php
diff --git a/Carousel.php b/src/Carousel.php
similarity index 100%
rename from Carousel.php
rename to src/Carousel.php
diff --git a/Collapse.php b/src/Collapse.php
similarity index 100%
rename from Collapse.php
rename to src/Collapse.php
diff --git a/Dropdown.php b/src/Dropdown.php
similarity index 100%
rename from Dropdown.php
rename to src/Dropdown.php
diff --git a/Html.php b/src/Html.php
similarity index 100%
rename from Html.php
rename to src/Html.php
diff --git a/InputWidget.php b/src/InputWidget.php
similarity index 100%
rename from InputWidget.php
rename to src/InputWidget.php
diff --git a/Modal.php b/src/Modal.php
similarity index 100%
rename from Modal.php
rename to src/Modal.php
diff --git a/Nav.php b/src/Nav.php
similarity index 100%
rename from Nav.php
rename to src/Nav.php
diff --git a/NavBar.php b/src/NavBar.php
similarity index 100%
rename from NavBar.php
rename to src/NavBar.php
diff --git a/Progress.php b/src/Progress.php
similarity index 100%
rename from Progress.php
rename to src/Progress.php
diff --git a/Tabs.php b/src/Tabs.php
similarity index 100%
rename from Tabs.php
rename to src/Tabs.php
diff --git a/ToggleButtonGroup.php b/src/ToggleButtonGroup.php
similarity index 100%
rename from ToggleButtonGroup.php
rename to src/ToggleButtonGroup.php
diff --git a/Widget.php b/src/Widget.php
similarity index 100%
rename from Widget.php
rename to src/Widget.php
diff --git a/tests/bootstrap.php b/tests/bootstrap.php
index a0c888d..40902b4 100644
--- a/tests/bootstrap.php
+++ b/tests/bootstrap.php
@@ -12,6 +12,6 @@ require_once(__DIR__ . '/../vendor/autoload.php');
 require_once(__DIR__ . '/../vendor/yiisoft/yii2/Yii.php');
 
 Yii::setAlias('@yiiunit/extensions/bootstrap', __DIR__);
-Yii::setAlias('@yii/bootstrap', dirname(__DIR__));
+Yii::setAlias('@yii/bootstrap', dirname(__DIR__) . '/src');
 
 require_once(__DIR__ . '/compatibility.php');
\ No newline at end of file