diff --git a/includes/Constants.php b/includes/Constants.php
index 314d3e82..7338ae28 100644
--- a/includes/Constants.php
+++ b/includes/Constants.php
@@ -1,5 +1,5 @@
 <?php
-namespace Vector;
+namespace MediaWiki\Skins\Vector;
 
 use FatalError;
 
diff --git a/includes/FeatureManagement/FeatureManager.php b/includes/FeatureManagement/FeatureManager.php
index f869cd4a..cbcb508c 100644
--- a/includes/FeatureManagement/FeatureManager.php
+++ b/includes/FeatureManagement/FeatureManager.php
@@ -20,9 +20,9 @@
  * @since 1.35
  */
 
-namespace Vector\FeatureManagement;
+namespace MediaWiki\Skins\Vector\FeatureManagement;
 
-use Vector\FeatureManagement\Requirements\SimpleRequirement;
+use MediaWiki\Skins\Vector\FeatureManagement\Requirements\SimpleRequirement;
 use Wikimedia\Assert\Assert;
 
 /**
@@ -33,7 +33,7 @@ use Wikimedia\Assert\Assert;
  *
  * @unstable
  *
- * @package Vector\FeatureManagement
+ * @package MediaWiki\Skins\Vector\FeatureManagement
  * @internal
  */
 final class FeatureManager {
diff --git a/includes/FeatureManagement/Requirement.php b/includes/FeatureManagement/Requirement.php
index 6d0c01c5..a02810fd 100644
--- a/includes/FeatureManagement/Requirement.php
+++ b/includes/FeatureManagement/Requirement.php
@@ -20,7 +20,7 @@
  * @since 1.35
  */
 
-namespace Vector\FeatureManagement;
+namespace MediaWiki\Skins\Vector\FeatureManagement;
 
 /**
  * NOTE: This API hasn't settled. It may change at any time without warning. Please don't bind to
@@ -28,7 +28,7 @@ namespace Vector\FeatureManagement;
  *
  * @unstable
  *
- * @package Vector\FeatureManagement
+ * @package MediaWiki\Skins\Vector\FeatureManagement
  * @internal
  */
 interface Requirement {
diff --git a/includes/FeatureManagement/Requirements/DynamicConfigRequirement.php b/includes/FeatureManagement/Requirements/DynamicConfigRequirement.php
index 0e8662bf..e8e9e3ef 100644
--- a/includes/FeatureManagement/Requirements/DynamicConfigRequirement.php
+++ b/includes/FeatureManagement/Requirements/DynamicConfigRequirement.php
@@ -20,9 +20,9 @@
  * @since 1.35
  */
 
-namespace Vector\FeatureManagement\Requirements;
+namespace MediaWiki\Skins\Vector\FeatureManagement\Requirements;
 
-use Vector\FeatureManagement\Requirement;
+use MediaWiki\Skins\Vector\FeatureManagement\Requirement;
 
 /**
  * Some application state changes throughout the lifetime of the application, e.g. `wgSitename` or
@@ -61,7 +61,7 @@ use Vector\FeatureManagement\Requirement;
  *
  * @unstable
  *
- * @package Vector\FeatureManagement\Requirements
+ * @package MediaWiki\Skins\Vector\FeatureManagement\Requirements
  * @internal
  */
 final class DynamicConfigRequirement implements Requirement {
diff --git a/includes/FeatureManagement/Requirements/OverridableConfigRequirement.php b/includes/FeatureManagement/Requirements/OverridableConfigRequirement.php
index 0d6c261e..c33c9f29 100644
--- a/includes/FeatureManagement/Requirements/OverridableConfigRequirement.php
+++ b/includes/FeatureManagement/Requirements/OverridableConfigRequirement.php
@@ -19,12 +19,12 @@
  * @file
  */
 
-namespace Vector\FeatureManagement\Requirements;
+namespace MediaWiki\Skins\Vector\FeatureManagement\Requirements;
 
 use CentralIdLookup;
 use Config;
+use MediaWiki\Skins\Vector\FeatureManagement\Requirement;
 use User;
-use Vector\FeatureManagement\Requirement;
 use WebRequest;
 
 /**
@@ -63,7 +63,7 @@ use WebRequest;
  * NOTE: This API hasn't settled. It may change at any time without warning. Please don't bind to
  * it unless you absolutely need to
  *
- * @package Vector\FeatureManagement\Requirements
+ * @package MediaWiki\Skins\Vector\FeatureManagement\Requirements
  */
 final class OverridableConfigRequirement implements Requirement {
 
diff --git a/includes/FeatureManagement/Requirements/SimpleRequirement.php b/includes/FeatureManagement/Requirements/SimpleRequirement.php
index a3c6d91a..79908f76 100644
--- a/includes/FeatureManagement/Requirements/SimpleRequirement.php
+++ b/includes/FeatureManagement/Requirements/SimpleRequirement.php
@@ -20,9 +20,9 @@
  * @since 1.35
  */
 
-namespace Vector\FeatureManagement\Requirements;
+namespace MediaWiki\Skins\Vector\FeatureManagement\Requirements;
 
-use Vector\FeatureManagement\Requirement;
+use MediaWiki\Skins\Vector\FeatureManagement\Requirement;
 
 /**
  * NOTE: This API hasn't settled. It may change at any time without warning. Please don't bind to
@@ -30,7 +30,7 @@ use Vector\FeatureManagement\Requirement;
  *
  * @unstable
  *
- * @package Vector\FeatureManagement\Requirements
+ * @package MediaWiki\Skins\Vector\FeatureManagement\Requirements
  * @internal
  */
 class SimpleRequirement implements Requirement {
diff --git a/includes/Hooks.php b/includes/Hooks.php
index 2cd2632d..737781ce 100644
--- a/includes/Hooks.php
+++ b/includes/Hooks.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace Vector;
+namespace MediaWiki\Skins\Vector;
 
 use Config;
 use MediaWiki\Auth\Hook\LocalUserCreatedHook;
diff --git a/includes/ResourceLoader/VectorResourceLoaderUserModule.php b/includes/ResourceLoader/VectorResourceLoaderUserModule.php
index aca54239..afac964d 100644
--- a/includes/ResourceLoader/VectorResourceLoaderUserModule.php
+++ b/includes/ResourceLoader/VectorResourceLoaderUserModule.php
@@ -1,10 +1,10 @@
 <?php
 
-namespace Vector\ResourceLoader;
+namespace MediaWiki\Skins\Vector\ResourceLoader;
 
+use MediaWiki\Skins\Vector\Constants;
 use ResourceLoaderContext;
 use ResourceLoaderUserModule;
-use Vector\Constants;
 
 class VectorResourceLoaderUserModule extends ResourceLoaderUserModule {
 	/**
diff --git a/includes/ResourceLoader/VectorResourceLoaderUserStylesModule.php b/includes/ResourceLoader/VectorResourceLoaderUserStylesModule.php
index 6d997f9b..738ab855 100644
--- a/includes/ResourceLoader/VectorResourceLoaderUserStylesModule.php
+++ b/includes/ResourceLoader/VectorResourceLoaderUserStylesModule.php
@@ -1,10 +1,10 @@
 <?php
 
-namespace Vector\ResourceLoader;
+namespace MediaWiki\Skins\Vector\ResourceLoader;
 
+use MediaWiki\Skins\Vector\Constants;
 use ResourceLoaderContext;
 use ResourceLoaderUserStylesModule;
-use Vector\Constants;
 
 class VectorResourceLoaderUserStylesModule extends ResourceLoaderUserStylesModule {
 	/**
diff --git a/includes/ServiceWiring.php b/includes/ServiceWiring.php
index 979829be..6f29db71 100644
--- a/includes/ServiceWiring.php
+++ b/includes/ServiceWiring.php
@@ -23,10 +23,10 @@
  */
 
 use MediaWiki\MediaWikiServices;
-use Vector\Constants;
-use Vector\FeatureManagement\FeatureManager;
-use Vector\FeatureManagement\Requirements\DynamicConfigRequirement;
-use Vector\FeatureManagement\Requirements\OverridableConfigRequirement;
+use MediaWiki\Skins\Vector\Constants;
+use MediaWiki\Skins\Vector\FeatureManagement\FeatureManager;
+use MediaWiki\Skins\Vector\FeatureManagement\Requirements\DynamicConfigRequirement;
+use MediaWiki\Skins\Vector\FeatureManagement\Requirements\OverridableConfigRequirement;
 
 return [
 	Constants::SERVICE_FEATURE_MANAGER => static function ( MediaWikiServices $services ) {
diff --git a/includes/Services/LanguageService.php b/includes/Services/LanguageService.php
index c750977e..0bfeb5d5 100644
--- a/includes/Services/LanguageService.php
+++ b/includes/Services/LanguageService.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace Vector\Services;
+namespace MediaWiki\Skins\Vector\Services;
 
 class LanguageService {
 	/**
diff --git a/includes/SkinVector.php b/includes/SkinVector.php
index 20b4fb3f..02bc5677 100644
--- a/includes/SkinVector.php
+++ b/includes/SkinVector.php
@@ -22,7 +22,7 @@
  * @ingroup Skins
  */
 
-namespace Vector;
+namespace MediaWiki\Skins\Vector;
 
 use ExtensionRegistry;
 use Html;
diff --git a/includes/SkinVector22.php b/includes/SkinVector22.php
index 199d21cc..595e0a33 100644
--- a/includes/SkinVector22.php
+++ b/includes/SkinVector22.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace Vector;
+namespace MediaWiki\Skins\Vector;
 
 use MediaWiki\MediaWikiServices;
 
diff --git a/includes/SkinVectorLegacy.php b/includes/SkinVectorLegacy.php
index 8127656d..57b285ec 100644
--- a/includes/SkinVectorLegacy.php
+++ b/includes/SkinVectorLegacy.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace Vector;
+namespace MediaWiki\Skins\Vector;
 
 /**
  * @ingroup Skins
diff --git a/includes/VectorServices.php b/includes/VectorServices.php
index 0d3d5fd7..48a80efc 100644
--- a/includes/VectorServices.php
+++ b/includes/VectorServices.php
@@ -1,10 +1,10 @@
 <?php
 
-namespace Vector;
+namespace MediaWiki\Skins\Vector;
 
 use MediaWiki\MediaWikiServices;
-use Vector\FeatureManagement\FeatureManager;
-use Vector\Services\LanguageService;
+use MediaWiki\Skins\Vector\FeatureManagement\FeatureManager;
+use MediaWiki\Skins\Vector\Services\LanguageService;
 
 /**
  * A service locator for services specific to Vector.
diff --git a/skin.json b/skin.json
index faf2ffd2..392634f9 100644
--- a/skin.json
+++ b/skin.json
@@ -25,7 +25,7 @@
 	},
 	"ValidSkinNames": {
 		"vector-2022": {
-			"class": "Vector\\SkinVector22",
+			"class": "MediaWiki\\Skins\\Vector\\SkinVector22",
 			"args": [
 				{
 					"name": "vector-2022",
@@ -78,7 +78,7 @@
 			]
 		},
 		"vector": {
-			"class": "Vector\\SkinVectorLegacy",
+			"class": "MediaWiki\\Skins\\Vector\\SkinVectorLegacy",
 			"@args": "See SkinVector::__construct for more detail.",
 			"args": [
 				{
@@ -129,14 +129,17 @@
 		]
 	},
 	"AutoloadNamespaces": {
-		"Vector\\": "includes/"
+		"MediaWiki\\Skins\\Vector\\": "includes/"
+	},
+	"TestAutoloadNamespaces": {
+		"MediaWiki\\Skins\\Vector\\Tests\\": "tests/phpunit/"
 	},
 	"ConfigRegistry": {
 		"vector": "GlobalVarConfig::newInstance"
 	},
 	"HookHandlers": {
 		"VectorHooks": {
-			"class": "Vector\\Hooks"
+			"class": "MediaWiki\\Skins\\Vector\\Hooks"
 		}
 	},
 	"Hooks": {
@@ -151,10 +154,10 @@
 	"@note": "When modifying skins.vector.styles definition, make sure the installer still works",
 	"ResourceModules": {
 		"skins.vector.user": {
-			"class": "Vector\\ResourceLoader\\VectorResourceLoaderUserModule"
+			"class": "MediaWiki\\Skins\\Vector\\ResourceLoader\\VectorResourceLoaderUserModule"
 		},
 		"skins.vector.user.styles": {
-			"class": "Vector\\ResourceLoader\\VectorResourceLoaderUserStylesModule"
+			"class": "MediaWiki\\Skins\\Vector\\ResourceLoader\\VectorResourceLoaderUserStylesModule"
 		},
 		"skins.vector.search": {
 			"es6": true,
@@ -170,7 +173,7 @@
 				"resources/skins.vector.search/App.vue",
 				{
 					"name": "resources/skins.vector.search/config.json",
-					"callback": "Vector\\Hooks::getVectorWvuiSearchResourceLoaderConfig"
+					"callback": "MediaWiki\\Skins\\Vector\\Hooks::getVectorWvuiSearchResourceLoaderConfig"
 				}
 			],
 			"messages": [
@@ -299,7 +302,7 @@
 				"resources/skins.vector.es6/linkHijack.js",
 				{
 					"name": "resources/skins.vector.es6/config.json",
-					"callback": "Vector\\Hooks::getVectorResourceLoaderConfig"
+					"callback": "MediaWiki\\Skins\\Vector\\Hooks::getVectorResourceLoaderConfig"
 				}
 			],
 			"dependencies": [
@@ -316,7 +319,7 @@
 				"resources/skins.vector.js/skin.js",
 				{
 					"name": "resources/skins.vector.js/config.json",
-					"callback": "Vector\\Hooks::getVectorResourceLoaderConfig"
+					"callback": "MediaWiki\\Skins\\Vector\\Hooks::getVectorResourceLoaderConfig"
 				},
 				"resources/skins.vector.js/dropdownMenus.js",
 				"resources/skins.vector.js/sidebar.js",
diff --git a/tests/phpunit/integration/SkinVectorTest.php b/tests/phpunit/integration/SkinVectorTest.php
index 992263a0..a7c46001 100644
--- a/tests/phpunit/integration/SkinVectorTest.php
+++ b/tests/phpunit/integration/SkinVectorTest.php
@@ -4,12 +4,12 @@ namespace MediaWiki\Skins\Vector\Tests\Integration;
 use Exception;
 use HashConfig;
 use MediaWiki\MediaWikiServices;
+use MediaWiki\Skins\Vector\SkinVector22;
+use MediaWiki\Skins\Vector\SkinVectorLegacy;
 use MediaWikiIntegrationTestCase;
 use ReflectionMethod;
 use RequestContext;
 use Title;
-use Vector\SkinVector22;
-use Vector\SkinVectorLegacy;
 use Wikimedia\TestingAccessWrapper;
 
 /**
@@ -178,7 +178,7 @@ class SkinVectorTest extends MediaWikiIntegrationTestCase {
 	}
 
 	/**
-	 * @covers \Vector\SkinVector22::getTocData
+	 * @covers \MediaWiki\Skins\Vector\SkinVector22::getTocData
 	 * @dataProvider provideGetTOCData
 	 */
 	public function testGetTocData(
@@ -198,7 +198,7 @@ class SkinVectorTest extends MediaWikiIntegrationTestCase {
 	}
 
 	/**
-	 * @covers \Vector\SkinVector::getTemplateData
+	 * @covers \MediaWiki\Skins\Vector\SkinVector::getTemplateData
 	 */
 	public function testGetTemplateData() {
 		$title = Title::newFromText( 'SkinVector' );
@@ -422,7 +422,7 @@ class SkinVectorTest extends MediaWikiIntegrationTestCase {
 
 	/**
 	 * @dataProvider providerLanguageAlertRequirements
-	 * @covers \Vector\SkinVector::shouldLanguageAlertBeInSidebar
+	 * @covers \MediaWiki\Skins\Vector\SkinVector::shouldLanguageAlertBeInSidebar
 	 * @param array $requirements
 	 * @param Title $title
 	 * @param array $getLanguagesCached
diff --git a/tests/phpunit/integration/VectorHooksTest.php b/tests/phpunit/integration/VectorHooksTest.php
index 3b7fb0ae..27ffcf84 100644
--- a/tests/phpunit/integration/VectorHooksTest.php
+++ b/tests/phpunit/integration/VectorHooksTest.php
@@ -7,6 +7,10 @@
 namespace MediaWiki\Skins\Vector\Tests\Integration;
 
 use HashConfig;
+use MediaWiki\Skins\Vector\Constants;
+use MediaWiki\Skins\Vector\Hooks;
+use MediaWiki\Skins\Vector\SkinVector22;
+use MediaWiki\Skins\Vector\SkinVectorLegacy;
 use MediaWiki\User\UserOptionsManager;
 use MediaWikiIntegrationTestCase;
 use ReflectionMethod;
@@ -15,16 +19,12 @@ use ResourceLoaderContext;
 use RuntimeException;
 use Title;
 use User;
-use Vector\Constants;
-use Vector\Hooks;
-use Vector\SkinVector22;
-use Vector\SkinVectorLegacy;
 
 /**
  * Integration tests for Vector Hooks.
  *
  * @group Vector
- * @coversDefaultClass \Vector\Hooks
+ * @coversDefaultClass \MediaWiki\Skins\Vector\Hooks
  */
 class VectorHooksTest extends MediaWikiIntegrationTestCase {
 
diff --git a/tests/phpunit/unit/FeatureManagement/FeatureManagerTest.php b/tests/phpunit/unit/FeatureManagement/FeatureManagerTest.php
index fd60fc7b..73de2fe2 100644
--- a/tests/phpunit/unit/FeatureManagement/FeatureManagerTest.php
+++ b/tests/phpunit/unit/FeatureManagement/FeatureManagerTest.php
@@ -19,14 +19,14 @@
  * @since 1.35
  */
 
-namespace Vector\FeatureManagement\Tests;
+namespace MediaWiki\Skins\Vector\Tests\Unit\FeatureManagement;
 
-use Vector\FeatureManagement\FeatureManager;
+use MediaWiki\Skins\Vector\FeatureManagement\FeatureManager;
 
 /**
  * @group Vector
  * @group FeatureManagement
- * @coversDefaultClass \Vector\FeatureManagement\FeatureManager
+ * @coversDefaultClass \MediaWiki\Skins\Vector\FeatureManagement\FeatureManager
  */
 class FeatureManagerTest extends \MediaWikiUnitTestCase {
 
diff --git a/tests/phpunit/unit/FeatureManagement/Requirements/DynamicConfigRequirementTest.php b/tests/phpunit/unit/FeatureManagement/Requirements/DynamicConfigRequirementTest.php
index 19d82c38..9e6c2082 100644
--- a/tests/phpunit/unit/FeatureManagement/Requirements/DynamicConfigRequirementTest.php
+++ b/tests/phpunit/unit/FeatureManagement/Requirements/DynamicConfigRequirementTest.php
@@ -20,14 +20,14 @@
  * @since 1.35
  */
 
-namespace Vector\FeatureManagement\Tests;
+namespace MediaWiki\Skins\Vector\Tests\Unit\FeatureManagement\Requirements;
 
-use Vector\FeatureManagement\Requirements\DynamicConfigRequirement;
+use MediaWiki\Skins\Vector\FeatureManagement\Requirements\DynamicConfigRequirement;
 
 /**
  * @group Vector
  * @group FeatureManagement
- * @coversDefaultClass \Vector\FeatureManagement\Requirements\DynamicConfigRequirement
+ * @coversDefaultClass \MediaWiki\Skins\Vector\FeatureManagement\Requirements\DynamicConfigRequirement
  */
 class DynamicConfigRequirementTest extends \MediaWikiUnitTestCase {
 
diff --git a/tests/phpunit/unit/FeatureManagement/Requirements/OverridableConfigRequirementTest.php b/tests/phpunit/unit/FeatureManagement/Requirements/OverridableConfigRequirementTest.php
index 7e1501ce..9ba7f439 100644
--- a/tests/phpunit/unit/FeatureManagement/Requirements/OverridableConfigRequirementTest.php
+++ b/tests/phpunit/unit/FeatureManagement/Requirements/OverridableConfigRequirementTest.php
@@ -18,19 +18,19 @@
  * @file
  */
 
-namespace Vector\FeatureManagement\Tests;
+namespace MediaWiki\Skins\Vector\Tests\Unit\FeatureManagement\Requirements;
 
 use CentralIdLookup;
 use HashConfig;
+use MediaWiki\Skins\Vector\Constants;
+use MediaWiki\Skins\Vector\FeatureManagement\Requirements\OverridableConfigRequirement;
 use User;
-use Vector\Constants;
-use Vector\FeatureManagement\Requirements\OverridableConfigRequirement;
 use WebRequest;
 
 /**
  * @group Vector
  * @group FeatureManagement
- * @coversDefaultClass \Vector\FeatureManagement\Requirements\OverridableConfigRequirement
+ * @coversDefaultClass \MediaWiki\Skins\Vector\FeatureManagement\Requirements\OverridableConfigRequirement
  */
 class OverridableConfigRequirementTest extends \MediaWikiUnitTestCase {