diff --git a/file/lib/data/room/Room.class.php b/file/lib/data/room/Room.class.php
index ed864c6..37eadc0 100644
--- a/file/lib/data/room/Room.class.php
+++ b/file/lib/data/room/Room.class.php
@@ -1,7 +1,6 @@
 <?php
 namespace chat\data\room;
 use \chat\data\suspension\Suspension;
-use \wcf\system\cache\CacheHandler;
 use \wcf\system\WCF;
 
 /**
@@ -24,13 +23,6 @@ class Room extends \chat\data\CHATDatabaseObject implements \wcf\system\request\
 	 */
 	protected static $databaseTableIndexName = 'roomID';
 	
-	/**
-	 * Caches rooms.
-	 * 
-	 * @var	array<wcf\data\chat\room\ChatRoom>
-	 */
-	protected static $cache = null;
-	
 	/**
 	 * @see	\wcf\data\chat\room\ChatRoom::getTitle();
 	 */
@@ -121,16 +113,7 @@ public function countUsers() {
 	 * Loads the room cache.
 	 */
 	public static function getCache() {
-		if (self::$cache === null) {
-			CacheHandler::getInstance()->addResource(
-				'chatRooms',
-				CHAT_DIR.'cache/cache.rooms.php',
-				'\chat\system\cache\builder\RoomCacheBuilder'
-			);
-			self::$cache = CacheHandler::getInstance()->get('chatRooms');
-		}
-		
-		return self::$cache;
+		return \chat\system\cache\builder\RoomCacheBuilder::getInstance()->getData();
 	}
 	
 	/**
diff --git a/file/lib/data/room/RoomEditor.class.php b/file/lib/data/room/RoomEditor.class.php
index 6b1e4ab..0bb25f5 100644
--- a/file/lib/data/room/RoomEditor.class.php
+++ b/file/lib/data/room/RoomEditor.class.php
@@ -59,6 +59,7 @@ public static function deleteAll(array $objectIDs = array()) {
 	 * Clears the room cache.
 	 */
 	public static function resetCache() {
-		\wcf\system\cache\CacheHandler::getInstance()->clear(CHAT_DIR.'cache', 'cache.rooms.php');
+		\chat\system\cache\builder\RoomCacheBuilder::getInstance()->reset();
+		\chat\system\cache\builder\PermissionCacheBuilder::getInstance()->reset();
 	}
 }
diff --git a/file/lib/page/ChatPage.class.php b/file/lib/page/ChatPage.class.php
index aeecc49..6a0dbc3 100644
--- a/file/lib/page/ChatPage.class.php
+++ b/file/lib/page/ChatPage.class.php
@@ -1,7 +1,6 @@
 <?php
 namespace chat\page;
 use \chat\data;
-use \wcf\system\cache\CacheHandler;
 use \wcf\system\WCF;
 
 /**
diff --git a/file/lib/page/RoomListPage.class.php b/file/lib/page/RoomListPage.class.php
index 12fbe24..7e53879 100644
--- a/file/lib/page/RoomListPage.class.php
+++ b/file/lib/page/RoomListPage.class.php
@@ -1,7 +1,6 @@
 <?php
 namespace chat\page;
 use \chat\data;
-use \wcf\system\cache\CacheHandler;
 use \wcf\system\exception\IllegalLinkException;
 use \wcf\system\WCF;
 
diff --git a/file/lib/system/cache/builder/PermissionCacheBuilder.class.php b/file/lib/system/cache/builder/PermissionCacheBuilder.class.php
index 0417dc2..c2402c8 100644
--- a/file/lib/system/cache/builder/PermissionCacheBuilder.class.php
+++ b/file/lib/system/cache/builder/PermissionCacheBuilder.class.php
@@ -11,20 +11,18 @@
  * @package	be.bastelstu.chat
  * @subpackage	system.cache.builder
  */
-class PermissionCacheBuilder implements \wcf\system\cache\builder\ICacheBuilder {
+class PermissionCacheBuilder implements \wcf\system\cache\builder\AbstractCacheBuilder {
 	/**
-	 * @see wcf\system\cache\ICacheBuilder::getData()
+	 * @see wcf\system\cache\AbstractCacheBuilder::rebuild()
 	 */
-	public function getData(array $cacheResource) {
+	public function rebuild(array $parameters) {
 		$data = array();
-		list(, $groupIDsStr) = explode('-', $cacheResource['cache']);
-		$groupIDs = explode(',', $groupIDsStr);
 		
-		if (count($groupIDs)) {
+		if (!empty($parameters)) {
 			$conditionBuilder = new \wcf\system\database\util\PreparedStatementConditionBuilder();
 			$conditionBuilder->add('acl_option.objectTypeID = ?', array(\wcf\system\acl\ACLHandler::getInstance()->getObjectTypeID('be.bastelstu.chat.room')));
 			$conditionBuilder->add('option_to_group.optionID = acl_option.optionID');
-			$conditionBuilder->add('option_to_group.groupID IN (?)', array($groupIDs));
+			$conditionBuilder->add('option_to_group.groupID IN (?)', array($parameters));
 			$sql = "SELECT		option_to_group.groupID, option_to_group.objectID AS roomID, option_to_group.optionValue,
 						acl_option.optionName AS permission
 				FROM		wcf".WCF_N."_acl_option acl_option,
diff --git a/file/lib/system/cache/builder/RoomCacheBuilder.class.php b/file/lib/system/cache/builder/RoomCacheBuilder.class.php
index 47f7f3d..f08969d 100644
--- a/file/lib/system/cache/builder/RoomCacheBuilder.class.php
+++ b/file/lib/system/cache/builder/RoomCacheBuilder.class.php
@@ -10,11 +10,11 @@
  * @package	be.bastelstu.chat
  * @subpackage	system.cache.builder
  */
-class RoomCacheBuilder implements \wcf\system\cache\builder\ICacheBuilder {
+class RoomCacheBuilder implements \wcf\system\cache\builder\AbstractCacheBuilder {
 	/**
-	 * @see	\wcf\system\cache\ICacheBuilder::getData()
+	 * @see	\wcf\system\cache\AbstractCacheBuilder::rebuild()
 	 */
-	public function getData(array $cacheResource) {
+	public function rebuild(array $parameters) {
 		// get all chat rooms
 		$roomList = new \chat\data\room\RoomList();
 		$roomList->sqlOrderBy = "room.position";
diff --git a/file/lib/system/permission/PermissionHandler.class.php b/file/lib/system/permission/PermissionHandler.class.php
index a47b84d..9af5c00 100644
--- a/file/lib/system/permission/PermissionHandler.class.php
+++ b/file/lib/system/permission/PermissionHandler.class.php
@@ -1,7 +1,6 @@
 <?php
 namespace chat\system\permission;
 use \wcf\system\acl\ACLHandler;
-use \wcf\system\cache\CacheHandler;
 use \wcf\system\package\PackageDependencyHandler;
 use \wcf\system\WCF;
 
@@ -35,10 +34,7 @@ public function __construct(\wcf\data\user\User $user = null) {
 		$ush = \wcf\system\user\storage\UserStorageHandler::getInstance();
 		
 		// get groups permissions
-		$groups = implode(',', $user->getGroupIDs());
-		$groupsFileName = \wcf\util\StringUtil::getHash(implode('-', $user->getGroupIDs()));
-		CacheHandler::getInstance()->addResource('permission-'.$groups, WCF_DIR.'cache/cache.permission-'.$groupsFileName.'.php', '\chat\system\cache\builder\PermissionCacheBuilder');
-		$this->chatPermissions = CacheHandler::getInstance()->get('permission-'.$groups);
+		$this->chatPermissions = \chat\system\cache\builder\PermissionCacheBuilder::getInstance()->getData($user->getGroupIDs);
 		
 		// get user permissions
 		if ($user->userID) {
@@ -106,6 +102,6 @@ public static function clearCache() {
 		$ush = \wcf\system\user\storage\UserStorageHandler::getInstance();
 		
 		$ush->resetAll('chatUserPermissions', $packageID);
-		\wcf\system\cache\CacheHandler::getInstance()->clear(WCF_DIR.'cache', 'cache.permission-[a-f0-9]{40}.php');
+		\chat\system\cache\builder\PermissionCacheBuilder::getInstance()->reset();
 	}
 }