diff --git a/core/Migrations/Version20170927145820.php b/core/Migrations/Version20170927145820.php
new file mode 100644
index 000000000000..906abc89c363
--- /dev/null
+++ b/core/Migrations/Version20170927145820.php
@@ -0,0 +1,57 @@
+<?php
+namespace OC\Migrations;
+
+use Doctrine\DBAL\Schema\Schema;
+use OCP\Migration\ISchemaMigration;
+use Doctrine\DBAL\Types\Type;
+
+class Version20170927145820 implements ISchemaMigration {
+
+	public function changeSchema(Schema $schema, array $options) {
+		$prefix = $options['tablePrefix'];
+
+		// Backend Groups Table
+		$table = $schema->createTable("{$prefix}backend_groups");
+		$table->addColumn('id', Type::INTEGER, [
+			'autoincrement' => true,
+			'unsigned' => true,
+			'notnull' => true,
+		]);
+		$table->addColumn('group_id', Type::STRING, [
+			'notnull' => true,
+			'length' => 255,
+		]);
+		$table->addColumn('display_name', Type::STRING, [
+			'notnull' => false,
+			'length' => 255,
+		]);
+		$table->addColumn('backend', Type::STRING, [
+			'notnull' => true,
+			'length' => 64,
+		]);
+		$table->setPrimaryKey(['id']);
+
+		// Group Memberships Table
+		$table = $schema->createTable("{$prefix}memberships");
+		$table->addColumn('backend_group_id', Type::INTEGER, [
+			'notnull' => true,
+			'unsigned' => true,
+		]);
+		$table->addColumn('account_id', Type::BIGINT, [
+			'notnull' => true,
+			'unsigned' => true,
+		]);
+		$table->addColumn('membership_type', Type::SMALLINT, [
+			'notnull' => true,
+			'comment' => '0: GroupUser, 1: GroupAdmin'
+		]);
+
+		// This set of values has to be unique
+		$table->addUniqueIndex(['backend_group_id', 'account_id', 'membership_type'], 'group_account_membership_index');
+
+		//TODO: Do it later since it requires changes here for Oracle https://github.com/owncloud/core/blob/master/lib/private/DB/OracleMigrator.php#L158-L160
+		// Add foreign keys on backend_group and accounts tables
+		//$table->addForeignKeyConstraint("{$prefix}backend_groups",array('backend_group_id'), array('id'));
+		//$table->addForeignKeyConstraint("{$prefix}accounts", array('account_id'), array('id'));
+    }
+}
diff --git a/lib/private/Group/BackendGroup.php b/lib/private/Group/BackendGroup.php
new file mode 100644
index 000000000000..2f3748a6c547
--- /dev/null
+++ b/lib/private/Group/BackendGroup.php
@@ -0,0 +1,62 @@
+<?php
+/**
+ * @author Piotr Mrowczynski <piotr@owncloud.com>
+ *
+ * @copyright Copyright (c) 2017, ownCloud GmbH
+ * @license AGPL-3.0
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+
+namespace OC\Group;
+
+use OCP\AppFramework\Db\Entity;
+use OCP\GroupInterface;
+
+/**
+ * Class BackendGroup
+ *
+ * @method int getGroupId()
+ * @method string getDisplayName()
+ * @method void setDisplayName(string $displayName)
+ * @method string getBackend()
+ * @method void setBackend(string $backEnd)
+ *
+ * @package OC\Group
+ */
+class BackendGroup extends Entity {
+
+	protected $groupId;
+	protected $displayName;
+	protected $backend;
+
+	public function __construct() { }
+
+	public function setGroupId($gid) {
+		parent::setter('groupId', [$gid]);
+	}
+
+	/**
+	 * @return GroupInterface
+	 */
+	public function getBackendInstance() {
+		$backendClass = $this->getBackend();
+		if (empty($backendClass)) {
+			return null;
+		}
+
+		return \OC::$server->getGroupManager()->getBackend($backendClass);
+	}
+
+}
\ No newline at end of file
diff --git a/lib/private/Group/GroupMapper.php b/lib/private/Group/GroupMapper.php
new file mode 100644
index 000000000000..931a89ce1368
--- /dev/null
+++ b/lib/private/Group/GroupMapper.php
@@ -0,0 +1,75 @@
+<?php
+/**
+ * @author Piotr Mrowczynski <piotr@owncloud.com>
+ *
+ * @copyright Copyright (c) 2017, ownCloud GmbH
+ * @license AGPL-3.0
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+
+namespace OC\Group;
+
+use OC\Group\BackendGroup;
+use OCP\AppFramework\Db\Mapper;
+use OCP\AppFramework\Db\Entity;
+use OCP\IConfig;
+use OCP\IDBConnection;
+
+class GroupMapper extends Mapper {
+
+	public function __construct(IDBConnection $db) {
+		parent::__construct($db, 'backend_groups', BackendGroup::class);
+	}
+
+	/**
+	 * @param BackendGroup $entity
+	 * @return Entity the saved entity with the set id
+	 */
+	public function insert(Entity $entity) {
+		// run the normal entity insert operation to get an id
+		return parent::insert($entity);
+	}
+
+	/**
+	 * @param string $uid
+	 * @return BackendGroup
+	 */
+	public function getGroup($gid) {
+		$qb = $this->db->getQueryBuilder();
+		$qb->select('*')
+			->from($this->getTableName())
+			->where($qb->expr()->eq('group_id', $qb->createNamedParameter($gid)));
+
+		return $this->findEntity($qb->getSQL(), $qb->getParameters());
+	}
+
+	/**
+	 * @param string $fieldName
+	 * @param string $pattern
+	 * @param integer $limit
+	 * @param integer $offset
+	 * @return BackendGroup[]
+	 */
+	public function search($fieldName, $pattern, $limit, $offset) {
+		$qb = $this->db->getQueryBuilder();
+		$qb->select('*')
+			->from($this->getTableName())
+			->where($qb->expr()->iLike($fieldName, $qb->createNamedParameter('%' . $this->db->escapeLikeParameter($pattern) . '%')))
+			->orderBy($fieldName);
+
+		return $this->findEntities($qb->getSQL(), $qb->getParameters(), $limit, $offset);
+	}
+
+}
diff --git a/lib/private/Group/Manager.php b/lib/private/Group/Manager.php
index 4b90edb58ce2..7d626001aac7 100644
--- a/lib/private/Group/Manager.php
+++ b/lib/private/Group/Manager.php
@@ -15,6 +15,7 @@
  * @author Thomas Müller <thomas.mueller@tmit.eu>
  * @author Vincent Petry <pvince81@owncloud.com>
  * @author voxsim <Simon Vocella>
+ * @authod Piotr Mrowczynski <piotr@owncloud.com>
  *
  * @copyright Copyright (c) 2017, ownCloud GmbH
  * @license AGPL-3.0
@@ -38,6 +39,8 @@
 use OC\Hooks\PublicEmitter;
 use OCP\GroupInterface;
 use OCP\IGroupManager;
+use OC\Group\GroupMapper;
+use OC\Group\Database;
 
 /**
  * Class Manager
@@ -55,34 +58,30 @@
  * @package OC\Group
  */
 class Manager extends PublicEmitter implements IGroupManager {
-	/**
-	 * @var GroupInterface[] $backends
-	 */
+	/** @var GroupInterface[] $backends */
 	private $backends = [];
 
-	/**
-	 * @var \OC\User\Manager $userManager
-	 */
+	/** @var \OC\User\Manager $userManager */
 	private $userManager;
 
-	/**
-	 * @var \OC\Group\Group[]
-	 */
+	/** @var \OC\Group\Group[] */
 	private $cachedGroups = [];
 
-	/**
-	 * @var \OC\Group\Group[]
-	 */
+	/** @var \OC\Group\Group[] */
 	private $cachedUserGroups = [];
 
 	/** @var \OC\SubAdmin */
 	private $subAdmin = null;
 
+	/** @var \OC\Group\GroupMapper */
+	private $groupMapper;
+
 	/**
 	 * @param \OC\User\Manager $userManager
 	 */
-	public function __construct(\OC\User\Manager $userManager) {
+	public function __construct(\OC\User\Manager $userManager, \OC\Group\GroupMapper $groupMapper) {
 		$this->userManager = $userManager;
+		$this->groupMapper = $groupMapper;
 		$cachedGroups = & $this->cachedGroups;
 		$cachedUserGroups = & $this->cachedUserGroups;
 		$this->listen('\OC\Group', 'postDelete', function ($group) use (&$cachedGroups, &$cachedUserGroups) {
@@ -136,7 +135,7 @@ public function clearBackends() {
 		$this->backends = [];
 		$this->clearCaches();
 	}
-	
+
 	protected function clearCaches() {
 		$this->cachedGroups = [];
 		$this->cachedUserGroups = [];
@@ -212,6 +211,21 @@ public function createGroup($gid) {
 		}
 	}
 
+
+	/**
+	 * @param string $gid
+	 * @param string $backendClass
+	 * @return BackendGroup|\OCP\AppFramework\Db\Entity
+	 */
+	private function createBackendGroup($gid, $backendClass) {
+		$account = new BackendGroup();
+		$account->setGroupId($gid);
+		$account->setDisplayName($gid);
+		$account->setBackend($backendClass);
+		$account = $this->groupMapper->insert($account);
+		return $account;
+	}
+
 	/**
 	 * @param string $search search string
 	 * @param int|null $limit limit
diff --git a/lib/private/Server.php b/lib/private/Server.php
index 59fa05491c4e..4324fdbd97f8 100644
--- a/lib/private/Server.php
+++ b/lib/private/Server.php
@@ -87,6 +87,7 @@
 use OC\Theme\ThemeService;
 use OC\User\AccountMapper;
 use OC\User\AccountTermMapper;
+use OC\Group\GroupMapper;
 use OCP\IL10N;
 use OCP\ILogger;
 use OCP\IServerContainer;
@@ -232,13 +233,16 @@ public function __construct($webRoot, \OC\Config $config) {
 		$this->registerService('AccountMapper', function(Server $c) {
 			return new AccountMapper($c->getConfig(), $c->getDatabaseConnection(), new AccountTermMapper($c->getDatabaseConnection()));
 		});
+		$this->registerService('GroupMapper', function(Server $c) {
+			return new GroupMapper($c->getDatabaseConnection());
+		});
 		$this->registerService('UserManager', function (Server $c) {
 			$config = $c->getConfig();
 			$logger = $c->getLogger();
 			return new \OC\User\Manager($config, $logger, $c->getAccountMapper());
 		});
 		$this->registerService('GroupManager', function (Server $c) {
-			$groupManager = new \OC\Group\Manager($this->getUserManager());
+			$groupManager = new \OC\Group\Manager($this->getUserManager(), $c->getGroupMapper());
 			$groupManager->listen('\OC\Group', 'preCreate', function ($gid) {
 				\OC_Hook::emit('OC_Group', 'pre_createGroup', ['run' => true, 'gid' => $gid]);
 			});
@@ -975,6 +979,13 @@ public function getAccountMapper() {
 		return $this->query('AccountMapper');
 	}
 
+	/**
+	 * @return \OC\Group\GroupMapper
+	 */
+	public function getGroupMapper() {
+		return $this->query('GroupMapper');
+	}
+
 	/**
 	 * @return \OC\Group\Manager
 	 */
diff --git a/tests/lib/Group/GroupMapperTest.php b/tests/lib/Group/GroupMapperTest.php
new file mode 100644
index 000000000000..49d3cbd55af9
--- /dev/null
+++ b/tests/lib/Group/GroupMapperTest.php
@@ -0,0 +1,151 @@
+<?php
+/**
+ * @author Piotr Mrowczynski <piotr@owncloud.com>
+ *
+ * @copyright Copyright (c) 2017, ownCloud GmbH
+ * @license AGPL-3.0
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+
+namespace Test\Group;
+
+use OC\Group\BackendGroup;
+use OC\Group\GroupMapper;
+use OCP\IConfig;
+use OCP\IDBConnection;
+use Test\TestCase;
+use OCP\AppFramework\Db\DoesNotExistException;
+
+/**
+ * Class GroupMapperTest
+ *
+ * @group DB
+ *
+ * @package Test\User
+ */
+class GroupMapperTest extends TestCase {
+
+	/** @var IConfig | \PHPUnit_Framework_MockObject_MockObject */
+	protected $config;
+
+	/** @var IDBConnection */
+	protected $connection;
+
+	/** @var GroupMapper */
+	protected $mapper;
+
+	public static function setUpBeforeClass() {
+		parent::setUpBeforeClass();
+		$mapper = \OC::$server->getGroupMapper();
+
+		\OC::$server->getDatabaseConnection()->beginTransaction();
+
+		// create test users
+		for ($i = 1; $i <= 4; $i++) {
+
+
+			try {
+				$backendGroup = $mapper->getGroup("TestFind$i");
+				$mapper->delete($backendGroup);
+			} catch (DoesNotExistException $ex) {
+			}
+
+			$backendGroup = new BackendGroup();
+			$backendGroup->setGroupId("TestFind$i");
+			$backendGroup->setDisplayName("TestFind$i");
+			$backendGroup->setBackend(self::class);
+
+			$mapper->insert($backendGroup);
+		}
+	}
+
+	public function setUp() {
+		parent::setUp();
+
+		$this->config = $this->createMock(IConfig::class);
+
+		$this->connection = \OC::$server->getDatabaseConnection();
+
+		$this->mapper = new GroupMapper(
+			$this->connection
+		);
+	}
+
+	public static function tearDownAfterClass () {
+		\OC::$server->getDatabaseConnection()->rollBack();
+		parent::tearDownAfterClass();
+	}
+
+	/**
+	 * find one record without lowercase
+	 */
+	public function testGet() {
+		$result = $this->mapper->getGroup("TestFind1");
+		$this->assertInstanceOf("OC\Group\BackendGroup", $result);
+	}
+
+	/**
+	 * find one record without lowercase
+	 */
+	public function testInsert() {
+		$backendGroup = new BackendGroup();
+		$backendGroup->setGroupId("TestFind5");
+		$backendGroup->setDisplayName("TestFind5");
+		$backendGroup->setBackend(self::class);
+
+		$mapper = \OC::$server->getGroupMapper();
+		$mapper->insert($backendGroup);
+		$result = $this->mapper->getGroup("TestFind5");
+		$this->assertInstanceOf("OC\Group\BackendGroup", $result);
+	}
+
+	/**
+	 * find nothing because of lower case
+	 *
+	 * @expectedException \OCP\AppFramework\Db\DoesNotExistException
+	 */
+	public function testGetNone() {
+		$this->mapper->getGroup("testfind1");
+	}
+
+
+	/**
+	 * find all, use lower case
+	 */
+	public function testFindAll() {
+		$result = $this->mapper->search('group_id',"testfind", null, null);
+		$this->assertEquals(5, count($result));
+	}
+
+
+	/**
+	 * find by userid, use lower case
+	 */
+	public function testFindByGroupId() {
+		$result = $this->mapper->search('group_id',"testfind1", null, null);
+		$this->assertEquals(1, count($result));
+		$this->assertEquals("TestFind1", array_shift($result)->getGroupId());
+	}
+
+	/**
+	 * find with limit and offset, use lower case
+	 */
+	public function testFindLimitAndOffset() {
+		$result = $this->mapper->search('group_id','Test', 2, 2);
+		$this->assertEquals(2, count($result));
+		$this->assertEquals("TestFind3", array_shift($result)->getGroupId());
+		$this->assertEquals("TestFind4", array_shift($result)->getGroupId());
+	}
+}
\ No newline at end of file
diff --git a/tests/lib/Group/ManagerTest.php b/tests/lib/Group/ManagerTest.php
index c49e6f501df4..beb77a2c1592 100644
--- a/tests/lib/Group/ManagerTest.php
+++ b/tests/lib/Group/ManagerTest.php
@@ -23,6 +23,7 @@
 namespace Test\Group;
 
 use OC\Group\Database;
+use OC\Group\GroupMapper;
 use OC\User\Manager;
 use OCP\IUser;
 use OCP\GroupInterface;
@@ -97,7 +98,11 @@ public function testGet() {
 		 * @var \OC\User\Manager $userManager
 		 */
 		$userManager = $this->createMock(Manager::class);
-		$manager = new \OC\Group\Manager($userManager);
+		/**
+		 * @var \OC\Group\GroupMapper $groupMapper
+		 */
+		$groupMapper = $this->createMock(GroupMapper::class);
+		$manager = new \OC\Group\Manager($userManager, $groupMapper);
 		$manager->addBackend($backend);
 
 		$group = $manager->get('group1');
@@ -110,7 +115,11 @@ public function testGetNoBackend() {
 		 * @var \OC\User\Manager $userManager
 		 */
 		$userManager = $this->createMock(Manager::class);
-		$manager = new \OC\Group\Manager($userManager);
+		/**
+		 * @var \OC\Group\GroupMapper $groupMapper
+		 */
+		$groupMapper = $this->createMock(GroupMapper::class);
+		$manager = new \OC\Group\Manager($userManager, $groupMapper);
 
 		$this->assertNull($manager->get('group1'));
 	}
@@ -129,7 +138,11 @@ public function testGetNotExists() {
 		 * @var \OC\User\Manager $userManager
 		 */
 		$userManager = $this->createMock(Manager::class);
-		$manager = new \OC\Group\Manager($userManager);
+		/**
+		 * @var \OC\Group\GroupMapper $groupMapper
+		 */
+		$groupMapper = $this->createMock(GroupMapper::class);
+		$manager = new \OC\Group\Manager($userManager, $groupMapper);
 		$manager->addBackend($backend);
 
 		$this->assertNull($manager->get('group1'));
@@ -143,7 +156,11 @@ public function testGetDeleted() {
 		 * @var \OC\User\Manager $userManager
 		 */
 		$userManager = $this->createMock(Manager::class);
-		$manager = new \OC\Group\Manager($userManager);
+		/**
+		 * @var \OC\Group\GroupMapper $groupMapper
+		 */
+		$groupMapper = $this->createMock(GroupMapper::class);
+		$manager = new \OC\Group\Manager($userManager, $groupMapper);
 		$manager->addBackend($backend);
 
 		$group = $manager->get('group1');
@@ -174,7 +191,11 @@ public function testGetMultipleBackends() {
 		 * @var \OC\User\Manager $userManager
 		 */
 		$userManager = $this->createMock(Manager::class);
-		$manager = new \OC\Group\Manager($userManager);
+		/**
+		 * @var \OC\Group\GroupMapper $groupMapper
+		 */
+		$groupMapper = $this->createMock(GroupMapper::class);
+		$manager = new \OC\Group\Manager($userManager, $groupMapper);
 		$manager->addBackend($backend1);
 		$manager->addBackend($backend2);
 
@@ -205,7 +226,11 @@ public function testCreate() {
 		 * @var \OC\User\Manager $userManager
 		 */
 		$userManager = $this->createMock(Manager::class);
-		$manager = new \OC\Group\Manager($userManager);
+		/**
+		 * @var \OC\Group\GroupMapper $groupMapper
+		 */
+		$groupMapper = $this->createMock(GroupMapper::class);
+		$manager = new \OC\Group\Manager($userManager, $groupMapper);
 		$manager->addBackend($backend);
 
 		$group = $manager->createGroup('group1');
@@ -228,7 +253,11 @@ public function testCreateExists() {
 		 * @var \OC\User\Manager $userManager
 		 */
 		$userManager = $this->createMock(Manager::class);
-		$manager = new \OC\Group\Manager($userManager);
+		/**
+		 * @var \OC\Group\GroupMapper $groupMapper
+		 */
+		$groupMapper = $this->createMock(GroupMapper::class);
+		$manager = new \OC\Group\Manager($userManager, $groupMapper);
 		$manager->addBackend($backend);
 
 		$group = $manager->createGroup('group1');
@@ -253,7 +282,11 @@ public function testSearch() {
 		 * @var \OC\User\Manager $userManager
 		 */
 		$userManager = $this->createMock(Manager::class);
-		$manager = new \OC\Group\Manager($userManager);
+		/**
+		 * @var \OC\Group\GroupMapper $groupMapper
+		 */
+		$groupMapper = $this->createMock(GroupMapper::class);
+		$manager = new \OC\Group\Manager($userManager, $groupMapper);
 		$manager->addBackend($backend);
 
 		$groups = $manager->search('1');
@@ -291,7 +324,11 @@ public function testSearchMultipleBackends() {
 		 * @var \OC\User\Manager $userManager
 		 */
 		$userManager = $this->createMock(Manager::class);
-		$manager = new \OC\Group\Manager($userManager);
+		/**
+		 * @var \OC\Group\GroupMapper $groupMapper
+		 */
+		$groupMapper = $this->createMock(GroupMapper::class);
+		$manager = new \OC\Group\Manager($userManager, $groupMapper);
 		$manager->addBackend($backend1);
 		$manager->addBackend($backend2);
 
@@ -332,7 +369,11 @@ public function testSearchMultipleBackendsLimitAndOffset() {
 		 * @var \OC\User\Manager $userManager
 		 */
 		$userManager = $this->createMock(Manager::class);
-		$manager = new \OC\Group\Manager($userManager);
+		/**
+		 * @var \OC\Group\GroupMapper $groupMapper
+		 */
+		$groupMapper = $this->createMock(GroupMapper::class);
+		$manager = new \OC\Group\Manager($userManager, $groupMapper);
 		$manager->addBackend($backend1);
 		$manager->addBackend($backend2);
 
@@ -365,8 +406,11 @@ public function testSearchResultExistsButGroupDoesNot() {
 		 * @var \OC\User\Manager $userManager
 		 */
 		$userManager = $this->createMock(Manager::class);
-
-		$manager = new \OC\Group\Manager($userManager);
+		/**
+		 * @var \OC\Group\GroupMapper $groupMapper
+		 */
+		$groupMapper = $this->createMock(GroupMapper::class);
+		$manager = new \OC\Group\Manager($userManager, $groupMapper);
 		$manager->addBackend($backend);
 
 		$groups = $manager->search('1');
@@ -405,7 +449,11 @@ public function testSearchBackendsForScope() {
 		 * @var \OC\User\Manager $userManager
 		 */
 		$userManager = $this->createMock(Manager::class);
-		$manager = new \OC\Group\Manager($userManager);
+		/**
+		 * @var \OC\Group\GroupMapper $groupMapper
+		 */
+		$groupMapper = $this->createMock(GroupMapper::class);
+		$manager = new \OC\Group\Manager($userManager, $groupMapper);
 		$manager->addBackend($backend1);
 		$manager->addBackend($backend2);
 
@@ -443,7 +491,11 @@ public function testGetUserGroups() {
 		 */
 		$userManager = $this->createMock(Manager::class);
 		$userBackend = $this->createMock(\OC_User_Backend::class);
-		$manager = new \OC\Group\Manager($userManager);
+		/**
+		 * @var \OC\Group\GroupMapper $groupMapper
+		 */
+		$groupMapper = $this->createMock(GroupMapper::class);
+		$manager = new \OC\Group\Manager($userManager, $groupMapper);
 		$manager->addBackend($backend);
 
 		$groups = $manager->getUserGroups($this->getTestUser('user1'));
@@ -497,7 +549,11 @@ public function testGetUserGroupsWithDeletedGroup() {
 		 */
 		$userManager = $this->createMock(Manager::class);
 		$userBackend = $this->createMock(\OC_User_Backend::class);
-		$manager = new \OC\Group\Manager($userManager);
+		/**
+		 * @var \OC\Group\GroupMapper $groupMapper
+		 */
+		$groupMapper = $this->createMock(GroupMapper::class);
+		$manager = new \OC\Group\Manager($userManager, $groupMapper);
 		$manager->addBackend($backend);
 
 		/** @var \OC\User\User $user */
@@ -530,7 +586,11 @@ public function testGetUserGroupsWithScope() {
 		 */
 		$userManager = $this->createMock(Manager::class);
 		$userBackend = $this->createMock(\OC_User_Backend::class);
-		$manager = new \OC\Group\Manager($userManager);
+		/**
+		 * @var \OC\Group\GroupMapper $groupMapper
+		 */
+		$groupMapper = $this->createMock(GroupMapper::class);
+		$manager = new \OC\Group\Manager($userManager, $groupMapper);
 		$manager->addBackend($backend);
 
 		$groups = $manager->getUserGroups($this->getTestUser('user1'));
@@ -560,7 +620,11 @@ public function testInGroup() {
 		 */
 		$userManager = $this->createMock(Manager::class);
 		$userBackend = $this->createMock(\OC_User_Backend::class);
-		$manager = new \OC\Group\Manager($userManager);
+		/**
+		 * @var \OC\Group\GroupMapper $groupMapper
+		 */
+		$groupMapper = $this->createMock(GroupMapper::class);
+		$manager = new \OC\Group\Manager($userManager, $groupMapper);
 		$manager->addBackend($backend);
 
 		$this->assertTrue($manager->isInGroup('user1', 'group1'));
@@ -584,7 +648,11 @@ public function testIsAdmin() {
 		 */
 		$userManager = $this->createMock(Manager::class);
 		$userBackend = $this->createMock(\OC_User_Backend::class);
-		$manager = new \OC\Group\Manager($userManager);
+		/**
+		 * @var \OC\Group\GroupMapper $groupMapper
+		 */
+		$groupMapper = $this->createMock(GroupMapper::class);
+		$manager = new \OC\Group\Manager($userManager, $groupMapper);
 		$manager->addBackend($backend);
 
 		$this->assertTrue($manager->isAdmin('user1'));
@@ -608,7 +676,11 @@ public function testNotAdmin() {
 		 */
 		$userManager = $this->createMock(Manager::class);
 		$userBackend = $this->createMock(\OC_User_Backend::class);
-		$manager = new \OC\Group\Manager($userManager);
+		/**
+		 * @var \OC\Group\GroupMapper $groupMapper
+		 */
+		$groupMapper = $this->createMock(GroupMapper::class);
+		$manager = new \OC\Group\Manager($userManager, $groupMapper);
 		$manager->addBackend($backend);
 
 		$this->assertFalse($manager->isAdmin('user1'));
@@ -644,7 +716,11 @@ public function testGetUserGroupsMultipleBackends() {
 		 */
 		$userManager = $this->createMock(Manager::class);
 		$userBackend = $this->createMock(\OC_User_Backend::class);
-		$manager = new \OC\Group\Manager($userManager);
+		/**
+		 * @var \OC\Group\GroupMapper $groupMapper
+		 */
+		$groupMapper = $this->createMock(GroupMapper::class);
+		$manager = new \OC\Group\Manager($userManager, $groupMapper);
 		$manager->addBackend($backend1);
 		$manager->addBackend($backend2);
 
@@ -709,7 +785,11 @@ public function testDisplayNamesInGroupWithOneUserBackend() {
 				}
 			}));
 
-		$manager = new \OC\Group\Manager($userManager);
+		/**
+		 * @var \OC\Group\GroupMapper $groupMapper
+		 */
+		$groupMapper = $this->createMock(GroupMapper::class);
+		$manager = new \OC\Group\Manager($userManager, $groupMapper);
 		$manager->addBackend($backend);
 
 		$users = $manager->displayNamesInGroup('testgroup', 'user3');
@@ -775,7 +855,11 @@ public function testDisplayNamesInGroupWithOneUserBackendWithLimitSpecified() {
 				}
 			}));
 
-		$manager = new \OC\Group\Manager($userManager);
+		/**
+		 * @var \OC\Group\GroupMapper $groupMapper
+		 */
+		$groupMapper = $this->createMock(GroupMapper::class);
+		$manager = new \OC\Group\Manager($userManager, $groupMapper);;
 		$manager->addBackend($backend);
 
 		$users = $manager->displayNamesInGroup('testgroup', 'user3', 1);
@@ -845,7 +929,11 @@ public function testDisplayNamesInGroupWithOneUserBackendWithLimitAndOffsetSpeci
 				}
 			}));
 
-		$manager = new \OC\Group\Manager($userManager);
+		/**
+		 * @var \OC\Group\GroupMapper $groupMapper
+		 */
+		$groupMapper = $this->createMock(GroupMapper::class);
+		$manager = new \OC\Group\Manager($userManager, $groupMapper);
 		$manager->addBackend($backend);
 
 		$users = $manager->displayNamesInGroup('testgroup', 'user3', 1, 1);
@@ -891,7 +979,11 @@ public function testDisplayNamesInGroupWithOneUserBackendAndSearchEmpty() {
 				}
 			}));
 
-		$manager = new \OC\Group\Manager($userManager);
+		/**
+		 * @var \OC\Group\GroupMapper $groupMapper
+		 */
+		$groupMapper = $this->createMock(GroupMapper::class);
+		$manager = new \OC\Group\Manager($userManager, $groupMapper);
 		$manager->addBackend($backend);
 
 		$users = $manager->displayNamesInGroup('testgroup', '');
@@ -935,7 +1027,11 @@ public function testDisplayNamesInGroupWithOneUserBackendAndSearchEmptyAndLimitS
 				}
 			}));
 
-		$manager = new \OC\Group\Manager($userManager);
+		/**
+		 * @var \OC\Group\GroupMapper $groupMapper
+		 */
+		$groupMapper = $this->createMock(GroupMapper::class);
+		$manager = new \OC\Group\Manager($userManager, $groupMapper);
 		$manager->addBackend($backend);
 
 		$users = $manager->displayNamesInGroup('testgroup', '', 1);
@@ -980,7 +1076,11 @@ public function testDisplayNamesInGroupWithOneUserBackendAndSearchEmptyAndLimitA
 				}
 			}));
 
-		$manager = new \OC\Group\Manager($userManager);
+		/**
+		 * @var \OC\Group\GroupMapper $groupMapper
+		 */
+		$groupMapper = $this->createMock(GroupMapper::class);
+		$manager = new \OC\Group\Manager($userManager, $groupMapper);
 		$manager->addBackend($backend);
 
 		$users = $manager->displayNamesInGroup('testgroup', '', 1, 1);
@@ -1012,7 +1112,11 @@ public function testGetUserGroupsWithAddUser() {
 		 * @var \OC\User\Manager $userManager
 		 */
 		$userManager = $this->createMock(Manager::class);
-		$manager = new \OC\Group\Manager($userManager);
+		/**
+		 * @var \OC\Group\GroupMapper $groupMapper
+		 */
+		$groupMapper = $this->createMock(GroupMapper::class);
+		$manager = new \OC\Group\Manager($userManager, $groupMapper);
 		$manager->addBackend($backend);
 
 		// prime cache
@@ -1059,7 +1163,11 @@ public function testGetUserGroupsWithRemoveUser() {
 		 * @var \OC\User\Manager $userManager
 		 */
 		$userManager = $this->createMock(Manager::class);
-		$manager = new \OC\Group\Manager($userManager);
+		/**
+		 * @var \OC\Group\GroupMapper $groupMapper
+		 */
+		$groupMapper = $this->createMock(GroupMapper::class);
+		$manager = new \OC\Group\Manager($userManager, $groupMapper);
 		$manager->addBackend($backend);
 
 		// prime cache
@@ -1093,7 +1201,11 @@ public function testGetUserIdGroups() {
 		 * @var \OC\User\Manager $userManager
 		 */
 		$userManager = $this->createMock(Manager::class);
-		$manager = new \OC\Group\Manager($userManager);
+		/**
+		 * @var \OC\Group\GroupMapper $groupMapper
+		 */
+		$groupMapper = $this->createMock(GroupMapper::class);
+		$manager = new \OC\Group\Manager($userManager, $groupMapper);
 		$manager->addBackend($backend);
 
 		$groups = $manager->getUserIdGroups('user1');
@@ -1123,7 +1235,11 @@ public function testGroupDisplayName() {
 		 * @var \OC\User\Manager $userManager
 		 */
 		$userManager = $this->createMock(Manager::class);
-		$manager = new \OC\Group\Manager($userManager);
+		/**
+		 * @var \OC\Group\GroupMapper $groupMapper
+		 */
+		$groupMapper = $this->createMock(GroupMapper::class);
+		$manager = new \OC\Group\Manager($userManager, $groupMapper);
 		$manager->addBackend($backend);
 
 		// group with display name
@@ -1192,7 +1308,11 @@ public function testFindUsersInGroupWithOneUserBackend() {
 				}
 			}));
 
-		$manager = new \OC\Group\Manager($userManager);
+		/**
+		 * @var \OC\Group\GroupMapper $groupMapper
+		 */
+		$groupMapper = $this->createMock(GroupMapper::class);
+		$manager = new \OC\Group\Manager($userManager, $groupMapper);
 		$manager->addBackend($backend);
 
 		$users = $manager->findUsersInGroup('testgroup', 'user3');
@@ -1258,7 +1378,11 @@ public function testFindUsersInGroupWithOneUserBackendWithLimitSpecified() {
 				}
 			}));
 
-		$manager = new \OC\Group\Manager($userManager);
+		/**
+		 * @var \OC\Group\GroupMapper $groupMapper
+		 */
+		$groupMapper = $this->createMock(GroupMapper::class);
+		$manager = new \OC\Group\Manager($userManager, $groupMapper);
 		$manager->addBackend($backend);
 
 		$users = $manager->findUsersInGroup('testgroup', 'user3', 1);
@@ -1328,7 +1452,11 @@ public function testFindUsersInGroupWithOneUserBackendWithLimitAndOffsetSpecifie
 				}
 			}));
 
-		$manager = new \OC\Group\Manager($userManager);
+		/**
+		 * @var \OC\Group\GroupMapper $groupMapper
+		 */
+		$groupMapper = $this->createMock(GroupMapper::class);
+		$manager = new \OC\Group\Manager($userManager, $groupMapper);
 		$manager->addBackend($backend);
 
 		$users = $manager->findUsersInGroup('testgroup', 'user3', 1, 1);
@@ -1374,7 +1502,11 @@ public function testFindUsersInGroupWithOneUserBackendAndSearchEmpty() {
 				}
 			}));
 
-		$manager = new \OC\Group\Manager($userManager);
+		/**
+		 * @var \OC\Group\GroupMapper $groupMapper
+		 */
+		$groupMapper = $this->createMock(GroupMapper::class);
+		$manager = new \OC\Group\Manager($userManager, $groupMapper);
 		$manager->addBackend($backend);
 
 		$users = $manager->findUsersInGroup('testgroup', '');
@@ -1418,7 +1550,11 @@ public function testFindUsersInGroupWithOneUserBackendAndSearchEmptyAndLimitSpec
 				}
 			}));
 
-		$manager = new \OC\Group\Manager($userManager);
+		/**
+		 * @var \OC\Group\GroupMapper $groupMapper
+		 */
+		$groupMapper = $this->createMock(GroupMapper::class);
+		$manager = new \OC\Group\Manager($userManager, $groupMapper);
 		$manager->addBackend($backend);
 
 		$users = $manager->findUsersInGroup('testgroup', '', 1);
@@ -1463,7 +1599,11 @@ public function testFindUsersInGroupWithOneUserBackendAndSearchEmptyAndLimitAndO
 				}
 			}));
 
-		$manager = new \OC\Group\Manager($userManager);
+		/**
+		 * @var \OC\Group\GroupMapper $groupMapper
+		 */
+		$groupMapper = $this->createMock(GroupMapper::class);
+		$manager = new \OC\Group\Manager($userManager, $groupMapper);
 		$manager->addBackend($backend);
 
 		$users = $manager->findUsersInGroup('testgroup', '', 1, 1);
diff --git a/version.php b/version.php
index 9b5ae3eccc36..f10e49539b97 100644
--- a/version.php
+++ b/version.php
@@ -25,10 +25,10 @@
 // We only can count up. The 4. digit is only for the internal patchlevel to trigger DB upgrades
 // between betas, final and RCs. This is _not_ the public version number. Reset minor/patchlevel
 // when updating major/minor version number.
-$OC_Version = [10, 0, 3, 3];
+$OC_Version = [10, 0, 4, 0];
 
 // The human readable string
-$OC_VersionString = '10.0.3';
+$OC_VersionString = '10.0.4';
 
 $OC_VersionCanBeUpgradedFrom = [[8, 2, 11],[9, 0, 9],[9, 1]];