diff --git a/.gitignore b/.gitignore
index 19ccdc0..f586439 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,4 @@
 /vendor
 /bin
 /tests-coverage
+.idea/
diff --git a/composer.json b/composer.json
index 562ae86..8fd7a0f 100644
--- a/composer.json
+++ b/composer.json
@@ -40,6 +40,7 @@
     },
     "require": {
         "php": ">=5.6",
-        "majora/framework-extra-bundle": "~1.1"
+        "majora/framework-extra-bundle": "~1.1",
+        "doctrine/orm": "^2.5"
     }
 }
diff --git a/composer.lock b/composer.lock
index 56f1411..90c5351 100644
--- a/composer.lock
+++ b/composer.lock
@@ -4,8 +4,8 @@
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     ],
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-    "content-hash": "f6b51a231d8fcdf71b3816016f22eb31",
+    "hash": "8d4034821426301e1da7b47a44a5b2b0",
+    "content-hash": "896abc5eeb511dd40ee5d3d0fd6cf5dc",
     "packages": [
         {
             "name": "doctrine/annotations",
@@ -284,6 +284,77 @@
             ],
             "time": "2015-12-25 13:18:31"
         },
+        {
+            "name": "doctrine/dbal",
+            "version": "v2.5.4",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/doctrine/dbal.git",
+                "reference": "abbdfd1cff43a7b99d027af3be709bc8fc7d4769"
+            },
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+            },
+            "require": {
+                "doctrine/common": ">=2.4,<2.7-dev",
+                "php": ">=5.3.2"
+            },
+            "require-dev": {
+                "phpunit/phpunit": "4.*",
+                "symfony/console": "2.*"
+            },
+            "suggest": {
+                "symfony/console": "For helpful console commands such as SQL execution and import of files."
+            },
+            "bin": [
+                "bin/doctrine-dbal"
+            ],
+            "type": "library",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "2.5.x-dev"
+                }
+            },
+            "autoload": {
+                "psr-0": {
+                    "Doctrine\\DBAL\\": "lib/"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Roman Borschel",
+                    "email": "roman@code-factory.org"
+                },
+                {
+                    "name": "Benjamin Eberlei",
+                    "email": "kontakt@beberlei.de"
+                },
+                {
+                    "name": "Guilherme Blanco",
+                    "email": "guilhermeblanco@gmail.com"
+                },
+                {
+                    "name": "Jonathan Wage",
+                    "email": "jonwage@gmail.com"
+                }
+            ],
+            "description": "Database Abstraction Layer",
+            "homepage": "http://www.doctrine-project.org",
+            "keywords": [
+                "database",
+                "dbal",
+                "persistence",
+                "queryobject"
+            ],
+            "time": "2016-01-05 22:11:12"
+        },
         {
             "name": "doctrine/inflector",
             "version": "v1.1.0",
@@ -351,6 +422,60 @@
             ],
             "time": "2015-11-06 14:35:42"
         },
+        {
+            "name": "doctrine/instantiator",
+            "version": "1.0.5",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/doctrine/instantiator.git",
+                "reference": "8e884e78f9f0eb1329e445619e04456e64d8051d"
+            },
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+                "shasum": ""
+            },
+            "require": {
+                "php": ">=5.3,<8.0-DEV"
+            },
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+                "athletic/athletic": "~0.1.8",
+                "ext-pdo": "*",
+                "ext-phar": "*",
+                "phpunit/phpunit": "~4.0",
+                "squizlabs/php_codesniffer": "~2.0"
+            },
+            "type": "library",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "1.0.x-dev"
+                }
+            },
+            "autoload": {
+                "psr-4": {
+                    "Doctrine\\Instantiator\\": "src/Doctrine/Instantiator/"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Marco Pivetta",
+                    "email": "ocramius@gmail.com",
+                    "homepage": "http://ocramius.github.com/"
+                }
+            ],
+            "description": "A small, lightweight utility to instantiate objects in PHP without invoking their constructors",
+            "homepage": "https://github.com/doctrine/instantiator",
+            "keywords": [
+                "constructor",
+                "instantiate"
+            ],
+            "time": "2015-06-14 21:17:01"
+        },
         {
             "name": "doctrine/lexer",
             "version": "v1.0.1",
@@ -405,18 +530,94 @@
             ],
             "time": "2014-09-09 13:34:57"
         },
+        {
+            "name": "doctrine/orm",
+            "version": "v2.5.4",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/doctrine/doctrine2.git",
+                "reference": "bc4ddbfb0114cb33438cc811c9a740d8aa304aab"
+            },
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+                "reference": "bc4ddbfb0114cb33438cc811c9a740d8aa304aab",
+                "shasum": ""
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+                "doctrine/collections": "~1.2",
+                "doctrine/common": ">=2.5-dev,<2.7-dev",
+                "doctrine/dbal": ">=2.5-dev,<2.6-dev",
+                "doctrine/instantiator": "~1.0.1",
+                "ext-pdo": "*",
+                "php": ">=5.4",
+                "symfony/console": "~2.5|~3.0"
+            },
+            "require-dev": {
+                "phpunit/phpunit": "~4.0",
+                "symfony/yaml": "~2.3|~3.0"
+            },
+            "suggest": {
+                "symfony/yaml": "If you want to use YAML Metadata Mapping Driver"
+            },
+            "bin": [
+                "bin/doctrine",
+                "bin/doctrine.php"
+            ],
+            "type": "library",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "2.6.x-dev"
+                }
+            },
+            "autoload": {
+                "psr-0": {
+                    "Doctrine\\ORM\\": "lib/"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Roman Borschel",
+                    "email": "roman@code-factory.org"
+                },
+                {
+                    "name": "Benjamin Eberlei",
+                    "email": "kontakt@beberlei.de"
+                },
+                {
+                    "name": "Guilherme Blanco",
+                    "email": "guilhermeblanco@gmail.com"
+                },
+                {
+                    "name": "Jonathan Wage",
+                    "email": "jonwage@gmail.com"
+                }
+            ],
+            "description": "Object-Relational-Mapper for PHP",
+            "homepage": "http://www.doctrine-project.org",
+            "keywords": [
+                "database",
+                "orm"
+            ],
+            "time": "2016-01-05 21:34:58"
+        },
         {
             "name": "majora/framework-extra-bundle",
-            "version": "1.1.0",
+            "version": "v1.1.2",
             "source": {
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                 "url": "https://github.com/LinkValue/MajoraFrameworkExtraBundle.git",
-                "reference": "e743802939119d4882cf167de54e49db9fd41d91"
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@@ -467,20 +668,20 @@
                 "framework",
                 "symfony"
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-            "time": "2016-03-11 00:25:29"
+            "time": "2016-03-15 10:00:24"
         },
         {
             "name": "paragonie/random_compat",
-            "version": "v1.2.1",
+            "version": "v1.4.1",
             "source": {
                 "type": "git",
                 "url": "https://github.com/paragonie/random_compat.git",
-                "reference": "f078eba3bcf140fd69b5fcc3ea5ac809abf729dc"
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-                "reference": "f078eba3bcf140fd69b5fcc3ea5ac809abf729dc",
+                "url": "https://api.github.com/repos/paragonie/random_compat/zipball/c7e26a21ba357863de030f0b9e701c7d04593774",
+                "reference": "c7e26a21ba357863de030f0b9e701c7d04593774",
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@@ -515,7 +716,7 @@
                 "pseudorandom",
                 "random"
             ],
-            "time": "2016-02-29 17:25:04"
+            "time": "2016-03-18 20:34:03"
         },
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@@ -841,16 +1042,16 @@
         },
         {
             "name": "symfony/symfony",
-            "version": "v3.0.3",
+            "version": "v3.0.4",
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                 "type": "git",
                 "url": "https://github.com/symfony/symfony.git",
-                "reference": "09ae53562ce8b7842206efa217ec81442975f055"
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-                "reference": "09ae53562ce8b7842206efa217ec81442975f055",
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@@ -933,10 +1134,7 @@
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-                    "Symfony\\Bridge\\Monolog\\": "src/Symfony/Bridge/Monolog/",
-                    "Symfony\\Bridge\\ProxyManager\\": "src/Symfony/Bridge/ProxyManager/",
-                    "Symfony\\Bridge\\Twig\\": "src/Symfony/Bridge/Twig/",
+                    "Symfony\\Bridge\\": "src/Symfony/Bridge/",
                     "Symfony\\Bundle\\": "src/Symfony/Bundle/",
                     "Symfony\\Component\\": "src/Symfony/Component/"
                 },
@@ -966,7 +1164,7 @@
             "keywords": [
                 "framework"
             ],
-            "time": "2016-02-28 21:33:29"
+            "time": "2016-03-30 10:41:14"
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         {
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@@ -1031,60 +1229,6 @@
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     ],
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-                "phpunit/phpunit": "~4.0",
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-            "license": [
-                "MIT"
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-                    "email": "ocramius@gmail.com",
-                    "homepage": "http://ocramius.github.com/"
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-            "description": "A small, lightweight utility to instantiate objects in PHP without invoking their constructors",
-            "homepage": "https://github.com/doctrine/instantiator",
-            "keywords": [
-                "constructor",
-                "instantiate"
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-            "time": "2015-06-14 21:17:01"
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@@ -1294,16 +1438,16 @@
         },
         {
             "name": "phpunit/php-code-coverage",
-            "version": "3.3.0",
+            "version": "3.3.1",
             "source": {
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                 "url": "https://github.com/sebastianbergmann/php-code-coverage.git",
-                "reference": "fe33716763b604ade4cb442c0794f5bd5ad73004"
+                "reference": "2431befdd451fac43fbcde94d1a92fb3b8b68f86"
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-                "reference": "fe33716763b604ade4cb442c0794f5bd5ad73004",
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@@ -1321,7 +1465,7 @@
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-                "ext-xdebug": ">=2.2.1",
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@@ -1353,7 +1497,7 @@
                 "testing",
                 "xunit"
             ],
-            "time": "2016-03-03 08:49:08"
+            "time": "2016-04-08 08:14:53"
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@@ -1535,16 +1679,16 @@
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-            "version": "5.2.10",
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-                "reference": "37fa29b17b87a3e9f0a4d77c42f0aac5183b84d1"
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-                "reference": "37fa29b17b87a3e9f0a4d77c42f0aac5183b84d1",
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@@ -1559,13 +1703,14 @@
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                 "phpunit/php-text-template": "~1.2",
-                "phpunit/php-timer": ">=1.0.6",
-                "phpunit/phpunit-mock-objects": ">=3.0.5",
+                "phpunit/php-timer": "^1.0.6",
+                "phpunit/phpunit-mock-objects": "^3.1",
                 "sebastian/comparator": "~1.1",
                 "sebastian/diff": "~1.2",
                 "sebastian/environment": "~1.3",
                 "sebastian/exporter": "~1.2",
                 "sebastian/global-state": "~1.0",
+                "sebastian/object-enumerator": "~1.0",
                 "sebastian/resource-operations": "~1.0",
                 "sebastian/version": "~1.0|~2.0",
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@@ -1579,7 +1724,7 @@
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@@ -1605,20 +1750,20 @@
                 "testing",
                 "xunit"
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-            "time": "2016-03-03 08:52:58"
+            "time": "2016-04-12 16:20:08"
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         {
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-            "version": "3.0.6",
+            "version": "3.1.3",
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                 "url": "https://github.com/sebastianbergmann/phpunit-mock-objects.git",
-                "reference": "49bc700750196c04dd6bc2c4c99cb632b893836b"
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-                "reference": "49bc700750196c04dd6bc2c4c99cb632b893836b",
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@@ -1636,7 +1781,7 @@
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+                    "dev-master": "3.1.x-dev"
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@@ -1661,7 +1806,7 @@
                 "mock",
                 "xunit"
             ],
-            "time": "2015-12-08 08:47:06"
+            "time": "2016-04-20 14:39:26"
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         {
             "name": "sebastian/code-unit-reverse-lookup",
@@ -1991,6 +2136,52 @@
             ],
             "time": "2015-10-12 03:26:01"
         },
+        {
+            "name": "sebastian/object-enumerator",
+            "version": "1.0.0",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/sebastianbergmann/object-enumerator.git",
+                "reference": "d4ca2fb70344987502567bc50081c03e6192fb26"
+            },
+            "dist": {
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+                "url": "https://api.github.com/repos/sebastianbergmann/object-enumerator/zipball/d4ca2fb70344987502567bc50081c03e6192fb26",
+                "reference": "d4ca2fb70344987502567bc50081c03e6192fb26",
+                "shasum": ""
+            },
+            "require": {
+                "php": ">=5.6",
+                "sebastian/recursion-context": "~1.0"
+            },
+            "require-dev": {
+                "phpunit/phpunit": "~5"
+            },
+            "type": "library",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "1.0.x-dev"
+                }
+            },
+            "autoload": {
+                "classmap": [
+                    "src/"
+                ]
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "BSD-3-Clause"
+            ],
+            "authors": [
+                {
+                    "name": "Sebastian Bergmann",
+                    "email": "sebastian@phpunit.de"
+                }
+            ],
+            "description": "Traverses array structures and object graphs to enumerate all referenced objects",
+            "homepage": "https://github.com/sebastianbergmann/object-enumerator/",
+            "time": "2016-01-28 13:25:10"
+        },
         {
             "name": "sebastian/recursion-context",
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diff --git a/src/Majora/Bundle/OAuthServerBundle/Resources/config/mapping/ORM/Token.orm.yml b/src/Majora/Bundle/OAuthServerBundle/Resources/config/mapping/ORM/Token.orm.yml
index 2236c78..bbdd5b4 100644
--- a/src/Majora/Bundle/OAuthServerBundle/Resources/config/mapping/ORM/Token.orm.yml
+++ b/src/Majora/Bundle/OAuthServerBundle/Resources/config/mapping/ORM/Token.orm.yml
@@ -14,8 +14,7 @@ Majora\Component\OAuth\Entity\Token:
             generator: { strategy: AUTO }
     fields:
         hash:
-            type: string
-            length: 128
+            type: text
         expireIn:
             type: integer
         expireAt:
diff --git a/src/Majora/Bundle/OAuthServerBundle/Resources/config/services/extensions.xml b/src/Majora/Bundle/OAuthServerBundle/Resources/config/services/extensions.xml
index 979371d..2027f72 100644
--- a/src/Majora/Bundle/OAuthServerBundle/Resources/config/services/extensions.xml
+++ b/src/Majora/Bundle/OAuthServerBundle/Resources/config/services/extensions.xml
@@ -22,6 +22,12 @@
             <argument type="service" id="majora.oauth.refresh_token.loader" />
         </service>
 
-    </services>
+        <!-- Client credentials grant extension -->
+        <service id="majora.oauth.grant_extension.client_credentials" public="false"
+                 class="Majora\Component\OAuth\GrantType\ClientCredentialsGrantExtension"
+        >
+        </service>
+
+</services>
 
 </container>
diff --git a/src/Majora/Bundle/OAuthServerBundle/Resources/config/services/server.xml b/src/Majora/Bundle/OAuthServerBundle/Resources/config/services/server.xml
index 9ea7357..3f6f649 100644
--- a/src/Majora/Bundle/OAuthServerBundle/Resources/config/services/server.xml
+++ b/src/Majora/Bundle/OAuthServerBundle/Resources/config/services/server.xml
@@ -23,6 +23,7 @@
             <argument type="collection">
                 <argument key="password" type="service" id="majora.oauth.grant_extension.password" />
                 <argument key="refresh_token" type="service" id="majora.oauth.grant_extension.refresh_token" />
+                <argument key="client_credentials" type="service" id="majora.oauth.grant_extension.client_credentials" />
             </argument>
         </service>
         <service id="oauth.server" alias="majora.oauth.server" />
diff --git a/src/Majora/Bundle/OAuthServerBundle/Security/AccessTokenAuthenticator.php b/src/Majora/Bundle/OAuthServerBundle/Security/AccessTokenAuthenticator.php
index 3279637..274c46d 100644
--- a/src/Majora/Bundle/OAuthServerBundle/Security/AccessTokenAuthenticator.php
+++ b/src/Majora/Bundle/OAuthServerBundle/Security/AccessTokenAuthenticator.php
@@ -53,7 +53,8 @@ public function getCredentials(Request $request)
 
             // token through headers
             case $request->headers->has('Authorization') :
-                if (!preg_match('#^Bearer ([\w]+)$#', $request->headers->get('Authorization'), $matches)) {
+                $accessTokenPattern = '[\w--_]+';
+                if (!preg_match(sprintf('#^Bearer (%s)$#', $accessTokenPattern), $request->headers->get('Authorization'), $matches)) {
                     break; // bad Authorization format
                 }
 
diff --git a/src/Majora/Component/OAuth/Entity/AccessToken.php b/src/Majora/Component/OAuth/Entity/AccessToken.php
index 417da66..e7c72bc 100644
--- a/src/Majora/Component/OAuth/Entity/AccessToken.php
+++ b/src/Majora/Component/OAuth/Entity/AccessToken.php
@@ -8,14 +8,14 @@
 use Majora\Component\OAuth\Model\RefreshTokenInterface;
 use Majora\Framework\Model\CollectionableInterface;
 use Majora\Framework\Model\CollectionableTrait;
-use Majora\Framework\Serializer\Model\SerializableTrait;
+use Majora\Framework\Normalizer\Model\NormalizableTrait;
 
 /**
  * Access token class.
  */
 class AccessToken extends Token implements AccessTokenInterface, CollectionableInterface
 {
-    use CollectionableTrait, SerializableTrait;
+    use CollectionableTrait, NormalizableTrait;
 
     /**
      * @var RefreshTokenInterface
@@ -51,7 +51,7 @@ public function getRefreshToken()
     public static function getScopes()
     {
         return array(
-            'default' => array('id', 'hash', 'expire_in', 'refresh_token', 'application@id', 'account@id'),
+            'default' => array('id', 'hash', 'expire_in', 'refresh_token', 'application@id', 'account@id?'),
         );
     }
 }
diff --git a/src/Majora/Component/OAuth/Entity/Account.php b/src/Majora/Component/OAuth/Entity/Account.php
index 6ecf4ca..2d01201 100644
--- a/src/Majora/Component/OAuth/Entity/Account.php
+++ b/src/Majora/Component/OAuth/Entity/Account.php
@@ -5,14 +5,14 @@
 use Majora\Component\OAuth\Model\AccountInterface;
 use Majora\Framework\Model\CollectionableInterface;
 use Majora\Framework\Model\CollectionableTrait;
-use Majora\Framework\Serializer\Model\SerializableTrait;
+use Majora\Framework\Normalizer\Model\NormalizableTrait;
 
 /**
  * Basic implementation on AccountInterface.
  */
 class Account implements AccountInterface, CollectionableInterface
 {
-    use CollectionableTrait, SerializableTrait;
+    use CollectionableTrait, NormalizableTrait;
 
     /**
      * @var int
@@ -183,9 +183,13 @@ public function getApplications()
 
     /**
      * @param array $applications
+     *
+     * @return self
      */
     public function setApplications($applications)
     {
         $this->applications = $applications;
+
+        return $this;
     }
 }
diff --git a/src/Majora/Component/OAuth/Entity/Application.php b/src/Majora/Component/OAuth/Entity/Application.php
index fd1e8ad..e44d939 100644
--- a/src/Majora/Component/OAuth/Entity/Application.php
+++ b/src/Majora/Component/OAuth/Entity/Application.php
@@ -5,14 +5,14 @@
 use Majora\Component\OAuth\Model\ApplicationInterface;
 use Majora\Framework\Model\CollectionableInterface;
 use Majora\Framework\Model\CollectionableTrait;
-use Majora\Framework\Serializer\Model\SerializableTrait;
+use Majora\Framework\Normalizer\Model\NormalizableTrait;
 
 /**
  * Basic implementation on ApplicationInterface.
  */
 class Application implements ApplicationInterface, CollectionableInterface
 {
-    use CollectionableTrait, SerializableTrait;
+    use CollectionableTrait, NormalizableTrait;
 
     /**
      * @var int
@@ -225,9 +225,13 @@ public function getAccounts()
 
     /**
      * @param array $accounts
+     *
+     * @return self
      */
     public function setAccounts($accounts)
     {
         $this->accounts = $accounts;
+
+        return $this;
     }
 }
diff --git a/src/Majora/Component/OAuth/Entity/RefreshToken.php b/src/Majora/Component/OAuth/Entity/RefreshToken.php
index 85829b1..6f00a2e 100644
--- a/src/Majora/Component/OAuth/Entity/RefreshToken.php
+++ b/src/Majora/Component/OAuth/Entity/RefreshToken.php
@@ -5,14 +5,14 @@
 use Majora\Component\OAuth\Model\RefreshTokenInterface;
 use Majora\Framework\Model\CollectionableInterface;
 use Majora\Framework\Model\CollectionableTrait;
-use Majora\Framework\Serializer\Model\SerializableTrait;
+use Majora\Framework\Normalizer\Model\NormalizableTrait;
 
 /**
  * Class RefreshToken is the default implementation of RefreshTokenInterface.
  */
 class RefreshToken extends Token implements RefreshTokenInterface, CollectionableInterface
 {
-    use CollectionableTrait, SerializableTrait;
+    use CollectionableTrait, NormalizableTrait;
 
     /**
      * {@inheritdoc}
diff --git a/src/Majora/Component/OAuth/Entity/Token.php b/src/Majora/Component/OAuth/Entity/Token.php
index e1abf21..a9eeff3 100644
--- a/src/Majora/Component/OAuth/Entity/Token.php
+++ b/src/Majora/Component/OAuth/Entity/Token.php
@@ -48,7 +48,7 @@ abstract class Token implements TokenInterface
     public function __construct(
         ApplicationInterface $application,
         AccountInterface $account = null,
-        $expireIn = TokenInterface::DEFAULT_TTL,
+        $expireIn = null,
         \DateTime $expireAt = null,
         $hash = null
     ) {
@@ -58,7 +58,7 @@ public function __construct(
         $this->expireAt = $expireAt ?: \DateTime::createFromFormat('U', time() + intval($expireIn));
 
         $this->hash = $hash ?: (new MessageDigestPasswordEncoder())->encodePassword(
-            sprintf('[%s\o/%s]', $application->getSecret(), $account->getPassword() ?: time()),
+            sprintf('[%s\o/%s]', $application->getSecret(), $account ? $account->getPassword() : time()),
             uniqid(mt_rand(), true)
         );
     }
diff --git a/src/Majora/Component/OAuth/GrantType/ClientCredentialsGrantExtension.php b/src/Majora/Component/OAuth/GrantType/ClientCredentialsGrantExtension.php
new file mode 100644
index 0000000..2d99b73
--- /dev/null
+++ b/src/Majora/Component/OAuth/GrantType/ClientCredentialsGrantExtension.php
@@ -0,0 +1,30 @@
+<?php
+
+namespace Majora\Component\OAuth\GrantType;
+
+use Majora\Component\OAuth\Entity\LoginAttempt;
+use Majora\Component\OAuth\Model\ApplicationInterface;
+use Symfony\Component\OptionsResolver\OptionsResolver;
+
+/**
+ * Built-in extension for client credentials granting.
+ */
+class ClientCredentialsGrantExtension implements GrantExtensionInterface
+{
+    /**
+     * @see GrantExtensionInterface::configureRequestParameters()
+     */
+    public function configureRequestParameters(OptionsResolver $requestResolver)
+    {
+        // No need to require additional request parameters.
+    }
+
+    /**
+     * @see GrantExtensionInterface::grant()
+     */
+    public function grant(ApplicationInterface $application, LoginAttempt $loginAttempt)
+    {
+        // No need to load an Account for this type of grant, the Application alone is enough.
+        return null;
+    }
+}
diff --git a/src/Majora/Component/OAuth/GrantType/GrantExtensionInterface.php b/src/Majora/Component/OAuth/GrantType/GrantExtensionInterface.php
index d0c513c..049d0bd 100644
--- a/src/Majora/Component/OAuth/GrantType/GrantExtensionInterface.php
+++ b/src/Majora/Component/OAuth/GrantType/GrantExtensionInterface.php
@@ -24,7 +24,7 @@ public function configureRequestParameters(OptionsResolver $requestResolver);
      * @param ApplicationInterface $application
      * @param LoginAttempt         $loginAttempt
      *
-     * @return AccountInterface
+     * @return AccountInterface|null
      *
      * @throws InvalidGrantException
      */
diff --git a/src/Majora/Component/OAuth/Loader/ORM/AccountLoader.php b/src/Majora/Component/OAuth/Loader/ORM/AccountLoader.php
index fa1ed75..c202fd0 100644
--- a/src/Majora/Component/OAuth/Loader/ORM/AccountLoader.php
+++ b/src/Majora/Component/OAuth/Loader/ORM/AccountLoader.php
@@ -17,7 +17,7 @@ class AccountLoader implements AccountLoaderInterface
     protected $accountRepository;
 
     /**
-     * Construct.
+     * Constructor.
      *
      * @param AccountRepository $accountRepository
      */
@@ -30,16 +30,26 @@ public function __construct(AccountRepository $accountRepository)
      * {@inheritdoc}
      */
     public function retrieveOnApplicationByUsername(ApplicationInterface $application, $username)
+    {
+        return $this->retrieveOnApplicationByUsernameQueryBuilder($application, $username)
+            ->getQuery()
+            ->getOneOrNullResult();
+    }
+
+    /**
+     * @param ApplicationInterface $application
+     * @param                      $username
+     *
+     * @return \Doctrine\ORM\QueryBuilder
+     */
+    public function retrieveOnApplicationByUsernameQueryBuilder(ApplicationInterface $application, $username)
     {
         return $this->accountRepository
             ->createQueryBuilder('ac')
-                ->innerJoin('ac.applications', 'app')
-                ->where('ac.username = :username')
-                    ->setParameter('username', $username)
-                ->andWhere('app.id = :application')
-                    ->setParameter('application', $application->getId())
-            ->getQuery()
-                ->getOneOrNullResult()
-        ;
+            ->innerJoin('ac.applications', 'app')
+            ->where('ac.username = :username')
+            ->setParameter('username', $username)
+            ->andWhere('app.id = :application')
+            ->setParameter('application', $application->getId());
     }
 }
diff --git a/src/Majora/Component/OAuth/Loader/ORM/ApplicationLoader.php b/src/Majora/Component/OAuth/Loader/ORM/ApplicationLoader.php
index 506e86c..f3f63e5 100644
--- a/src/Majora/Component/OAuth/Loader/ORM/ApplicationLoader.php
+++ b/src/Majora/Component/OAuth/Loader/ORM/ApplicationLoader.php
@@ -16,7 +16,7 @@ class ApplicationLoader implements ApplicationLoaderInterface
     protected $applicationRepository;
 
     /**
-     * Construct.
+     * Constructor.
      *
      * @param ApplicationRepository $applicationRepository
      */
@@ -29,15 +29,25 @@ public function __construct(ApplicationRepository $applicationRepository)
      * {@inheritdoc}
      */
     public function retrieveByApiKeyAndSecret($apiKey, $secret)
+    {
+        return $this->retrieveByApiKeyAndSecretQueryBuilder($apiKey, $secret)
+            ->getQuery()
+            ->getOneOrNullResult();
+    }
+
+    /**
+     * @param $apiKey
+     * @param $secret
+     *
+     * @return \Doctrine\ORM\QueryBuilder
+     */
+    public function retrieveByApiKeyAndSecretQueryBuilder($apiKey, $secret)
     {
         return $this->applicationRepository
             ->createQueryBuilder('a')
-                ->where('a.secret = :secret')
-                    ->setParameter('secret', $secret)
-                ->andWhere('a.apiKey = :api_key')
-                    ->setParameter('api_key', $apiKey)
-            ->getQuery()
-                ->getOneOrNullResult()
-        ;
+            ->where('a.secret = :secret')
+            ->setParameter('secret', $secret)
+            ->andWhere('a.apiKey = :api_key')
+            ->setParameter('api_key', $apiKey);
     }
 }
diff --git a/src/Majora/Component/OAuth/Loader/ORM/TokenLoader.php b/src/Majora/Component/OAuth/Loader/ORM/TokenLoader.php
index 0d7298f..af4d251 100644
--- a/src/Majora/Component/OAuth/Loader/ORM/TokenLoader.php
+++ b/src/Majora/Component/OAuth/Loader/ORM/TokenLoader.php
@@ -37,30 +37,48 @@ public function __construct(TokenRepository $tokenRepository, Clock $clock)
      * @see TokenLoaderInterface::retrieveByHash()
      */
     public function retrieveByHash($hash)
+    {
+        return $this->retrieveByHashQueryBuilder($hash)
+            ->getQuery()
+            ->setMaxResults(1)
+            ->getOneOrNullResult();
+    }
+
+    /**
+     * @param $hash
+     *
+     * @return \Doctrine\ORM\QueryBuilder
+     */
+    public function retrieveByHashQueryBuilder($hash)
     {
         return $this->tokenRepository
             ->createQueryBuilder('t')
-                ->where('t.hash = :hash')
-                    ->setParameter('hash', $hash)
-                ->andWhere('t.expireAt > :now')
-                    ->setParameter('now', $this->clock->now())
-            ->getQuery()
-                ->setMaxResults(1)
-                ->getOneOrNullResult()
-        ;
+            ->where('t.hash = :hash')
+            ->setParameter('hash', $hash)
+            ->andWhere('t.expireAt > :now')
+            ->setParameter('now', $this->clock->now());
     }
 
     /**
      * @see TokenLoaderInterface::retrieveExpired()
      */
     public function retrieveExpired(\DateTime $datetime = null)
+    {
+        return $this->retrieveExpiredQueryBuilder($datetime)
+            ->getQuery()
+            ->getResult();
+    }
+
+    /**
+     * @param \DateTime|null $datetime
+     *
+     * @return \Doctrine\ORM\QueryBuilder
+     */
+    public function retrieveExpiredQueryBuilder(\DateTime $datetime = null)
     {
         return $this->tokenRepository
             ->createQueryBuilder('t')
-                ->where('t.expireAt < :date')
-                ->setParameter('date', $datetime ?: $this->clock->now())
-            ->getQuery()
-                ->getResult()
-        ;
+            ->where('t.expireAt < :date')
+            ->setParameter('date', $datetime ?: $this->clock->now());
     }
 }
diff --git a/src/Majora/Component/OAuth/Tests/Loader/ORM/AccessTokenLoaderTest.php b/src/Majora/Component/OAuth/Tests/Loader/ORM/AccessTokenLoaderTest.php
new file mode 100644
index 0000000..4e709b6
--- /dev/null
+++ b/src/Majora/Component/OAuth/Tests/Loader/ORM/AccessTokenLoaderTest.php
@@ -0,0 +1,36 @@
+<?php
+
+namespace Majora\Component\OAuth\Tests\Loader\ORM;
+
+use Majora\Component\OAuth\Entity\AccessToken;
+use Majora\Component\OAuth\Loader\ORM\AccessTokenLoader;
+use Majora\Component\OAuth\Repository\ORM\AccessTokenRepository;
+use Majora\Framework\Date\Clock;
+use Symfony\Bridge\Doctrine\Test\DoctrineTestHelper;
+use Doctrine\ORM\Mapping\ClassMetadata;
+
+/**
+ * Unit tests class for Majora\Component\OAuth\Loader\ORM\AccessTokenLoader.
+ *
+ * @see \Majora\Component\OAuth\Loader\ORM\AccessTokenLoader
+ */
+class AccessTokenLoaderTest extends TokenLoaderTest
+{
+    /**
+     * @see \PHPUnit_Framework_TestCase::setUp()
+     */
+    public function setUp()
+    {
+        $this->clock = new Clock();
+
+        $this->tokenRepository = new AccessTokenRepository(
+            DoctrineTestHelper::createTestEntityManager(),
+            new ClassMetadata(AccessTokenRepository::class)
+        );
+
+        $this->tokenLoader = new AccessTokenLoader(
+            $this->tokenRepository,
+            $this->clock
+        );
+    }
+}
diff --git a/src/Majora/Component/OAuth/Tests/Loader/ORM/AccountLoaderTest.php b/src/Majora/Component/OAuth/Tests/Loader/ORM/AccountLoaderTest.php
new file mode 100644
index 0000000..777d4a5
--- /dev/null
+++ b/src/Majora/Component/OAuth/Tests/Loader/ORM/AccountLoaderTest.php
@@ -0,0 +1,70 @@
+<?php
+
+namespace Majora\Component\OAuth\Tests\Loader\ORM;
+
+use Majora\Component\OAuth\Loader\ORM\AccountLoader;
+use Majora\Component\OAuth\Repository\ORM\AccountRepository;
+use Prophecy\Argument;
+use Doctrine\ORM\Mapping\ClassMetadata;
+use Symfony\Bridge\Doctrine\Test\DoctrineTestHelper;
+
+/**
+ * Unit tests class for Majora\Component\OAuth\Loader\ORM\AccountLoader.
+ *
+ * @see \Majora\Component\OAuth\Loader\ORM\AccountLoader
+ */
+class AccountLoaderTest extends \PHPUnit_Framework_TestCase
+{
+    /**
+     * Tests __construct() method.
+     */
+    public function testConstructor()
+    {
+        $accountRepository = new AccountRepository(
+            DoctrineTestHelper::createTestEntityManager(),
+            new ClassMetadata(AccountRepository::class)
+        );
+
+        $accountLoader = new AccountLoader(
+            $accountRepository
+        );
+
+        $reflectedClass = new \ReflectionClass(AccountLoader::class);
+        $property = $reflectedClass->getProperty('accountRepository');
+        $property->setAccessible(true);
+
+        $this->assertEquals($property->getValue($accountLoader), $accountRepository);
+    }
+
+    /**
+     * Tests retrieveOnApplicationByUsernameQueryBuilder() method.
+     */
+    public function testRetrieveOnApplicationByUsernameQueryBuilder()
+    {
+        $accountRepository = new AccountRepository(
+            DoctrineTestHelper::createTestEntityManager(),
+            new ClassMetadata(AccountRepository::class)
+        );
+
+        $accountLoader = new AccountLoader(
+            $accountRepository
+        );
+
+        $application = $this->prophesize('Majora\Component\OAuth\Entity\Application');
+
+        $queryBuilder = $accountLoader->retrieveOnApplicationByUsernameQueryBuilder(
+            $application->reveal(),
+            Argument::any()
+        );
+
+        $query = $queryBuilder->getQuery();
+
+        $this->assertEquals(
+            $query->getDQL(),
+            sprintf(
+                'SELECT ac FROM %s ac INNER JOIN ac.applications app WHERE ac.username = :username AND app.id = :application',
+                AccountRepository::class
+            )
+        );
+    }
+}
diff --git a/src/Majora/Component/OAuth/Tests/Loader/ORM/ApplicationLoaderTest.php b/src/Majora/Component/OAuth/Tests/Loader/ORM/ApplicationLoaderTest.php
new file mode 100644
index 0000000..c54269d
--- /dev/null
+++ b/src/Majora/Component/OAuth/Tests/Loader/ORM/ApplicationLoaderTest.php
@@ -0,0 +1,62 @@
+<?php
+
+namespace Majora\Component\OAuth\Tests\Loader\ORM;
+
+use Majora\Component\OAuth\Loader\ORM\ApplicationLoader;
+use Majora\Component\OAuth\Repository\ORM\ApplicationRepository;
+use Prophecy\Argument;
+use Doctrine\ORM\Mapping\ClassMetadata;
+use Symfony\Bridge\Doctrine\Test\DoctrineTestHelper;
+
+/**
+ * Unit tests class for Majora\Component\OAuth\Loader\ORM\ApplicationLoader.
+ *
+ * @see \Majora\Component\OAuth\Loader\ORM\ApplicationLoader
+ */
+class ApplicationLoaderTest extends \PHPUnit_Framework_TestCase
+{
+    /**
+     * Tests __construct() method.
+     */
+    public function testConstructor()
+    {
+        $applicationRepository = new ApplicationRepository(
+            DoctrineTestHelper::createTestEntityManager(),
+            new ClassMetadata(ApplicationRepository::class)
+        );
+
+        $applicationLoader = new ApplicationLoader(
+            $applicationRepository
+        );
+
+        $reflectedClass = new \ReflectionClass(ApplicationLoader::class);
+        $property = $reflectedClass->getProperty('applicationRepository');
+        $property->setAccessible(true);
+
+        $this->assertEquals($property->getValue($applicationLoader), $applicationRepository);
+    }
+
+    /**
+     * Tests retrieveByApiKeyAndSecretQueryBuilder() method.
+     */
+    public function testRetrieveByApiKeyAndSecretQueryBuilder()
+    {
+        $applicationRepository = new ApplicationRepository(
+            DoctrineTestHelper::createTestEntityManager(),
+            new ClassMetadata(ApplicationRepository::class)
+        );
+
+        $applicationLoader = new ApplicationLoader(
+            $applicationRepository
+        );
+
+        $queryBuilder = $applicationLoader->retrieveByApiKeyAndSecretQueryBuilder(Argument::any(), Argument::any());
+
+        $query = $queryBuilder->getQuery();
+
+        $this->assertEquals(
+            $query->getDQL(),
+            sprintf('SELECT a FROM %s a WHERE a.secret = :secret AND a.apiKey = :api_key', ApplicationRepository::class)
+        );
+    }
+}
diff --git a/src/Majora/Component/OAuth/Tests/Loader/ORM/RefreshTokenLoaderTest.php b/src/Majora/Component/OAuth/Tests/Loader/ORM/RefreshTokenLoaderTest.php
new file mode 100644
index 0000000..c2ad564
--- /dev/null
+++ b/src/Majora/Component/OAuth/Tests/Loader/ORM/RefreshTokenLoaderTest.php
@@ -0,0 +1,36 @@
+<?php
+
+namespace Majora\Component\OAuth\Tests\Loader\ORM;
+
+use Majora\Component\OAuth\Entity\RefreshToken;
+use Majora\Component\OAuth\Loader\ORM\RefreshTokenLoader;
+use Majora\Component\OAuth\Repository\ORM\RefreshTokenRepository;
+use Majora\Framework\Date\Clock;
+use Symfony\Bridge\Doctrine\Test\DoctrineTestHelper;
+use Doctrine\ORM\Mapping\ClassMetadata;
+
+/**
+ * Unit tests class for Majora\Component\OAuth\Loader\ORM\RefreshTokenLoader.
+ *
+ * @see \Majora\Component\OAuth\Loader\ORM\RefreshTokenLoader
+ */
+class RefreshTokenLoaderTest extends TokenLoaderTest
+{
+    /**
+     * @see \PHPUnit_Framework_TestCase::setUp()
+     */
+    public function setUp()
+    {
+        $this->clock = new Clock();
+
+        $this->tokenRepository = new RefreshTokenRepository(
+            DoctrineTestHelper::createTestEntityManager(),
+            new ClassMetadata(RefreshTokenRepository::class)
+        );
+
+        $this->tokenLoader = new RefreshTokenLoader(
+            $this->tokenRepository,
+            $this->clock
+        );
+    }
+}
diff --git a/src/Majora/Component/OAuth/Tests/Loader/ORM/TokenLoaderTest.php b/src/Majora/Component/OAuth/Tests/Loader/ORM/TokenLoaderTest.php
new file mode 100644
index 0000000..a1e91a0
--- /dev/null
+++ b/src/Majora/Component/OAuth/Tests/Loader/ORM/TokenLoaderTest.php
@@ -0,0 +1,109 @@
+<?php
+
+namespace Majora\Component\OAuth\Tests\Loader\ORM;
+
+use Majora\Component\OAuth\Entity\Token;
+use Majora\Component\OAuth\Loader\ORM\TokenLoader;
+use Majora\Component\OAuth\Repository\ORM\TokenRepository;
+use Majora\Framework\Date\Clock;
+use Symfony\Bridge\Doctrine\Test\DoctrineTestHelper;
+use Doctrine\ORM\Mapping\ClassMetadata;
+
+/**
+ * Unit tests class for Majora\Component\OAuth\Loader\ORM\TokenLoader.
+ *
+ * @see \Majora\Component\OAuth\Loader\ORM\TokenLoader
+ */
+abstract class TokenLoaderTest extends \PHPUnit_Framework_TestCase
+{
+    /**
+     * @var \Majora\Framework\Date\Clock
+     */
+    protected $clock;
+
+    /**
+     * @var \Majora\Component\OAuth\Loader\TokenLoaderInterface
+     */
+    protected $tokenLoader;
+
+    /**
+     * @var \Majora\Component\OAuth\Repository\TokenRepositoryInterface
+     */
+    protected $tokenRepository;
+
+    /**
+     * @see \PHPUnit_Framework_TestCase::setUp()
+     */
+    public function setUp()
+    {
+        $this->clock = new Clock();
+
+        $this->tokenRepository = new TokenRepository(
+            DoctrineTestHelper::createTestEntityManager(),
+            new ClassMetadata(TokenRepository::class)
+        );
+
+        $this->tokenLoader = new TokenLoader(
+            $this->tokenRepository,
+            $this->clock
+        );
+    }
+
+    /**
+     * Tests __construct() method.
+     */
+    public function testConstructor()
+    {
+        $tokenRepositoryClass = $this->tokenRepository->getClassName();
+        $tokenLoaderClass = get_class($this->tokenLoader);
+
+        $tokenRepository = new $tokenRepositoryClass(
+            DoctrineTestHelper::createTestEntityManager(),
+            new ClassMetadata($tokenRepositoryClass)
+        );
+
+        $tokenLoader = new $tokenLoaderClass(
+            $tokenRepository,
+            $this->clock
+        );
+
+        $reflectedClass = new \ReflectionClass($tokenLoaderClass);
+        $property = $reflectedClass->getProperty('tokenRepository');
+        $property->setAccessible(true);
+
+        $this->assertEquals($property->getValue($tokenLoader), $tokenRepository);
+    }
+
+    /**
+     * Tests retrieveByHashQueryBuilder() method.
+     */
+    public function testRetrieveByHashQueryBuilder()
+    {
+        $queryBuilder = $this->tokenLoader->retrieveByHashQueryBuilder('1234');
+
+        $query = $queryBuilder->getQuery();
+
+        $this->assertEquals(
+            $query->getDQL(),
+            sprintf(
+                'SELECT t FROM %s t WHERE t.hash = :hash AND t.expireAt > :now',
+                $this->tokenRepository->getClassName()
+            )
+        );
+    }
+
+    /**
+     * Tests retrieveExpiredQueryBuilder() method.
+     */
+    public function testRetrieveExpiredQueryBuilder()
+    {
+        $queryBuilder = $this->tokenLoader->retrieveExpiredQueryBuilder($this->clock->now());
+
+        $query = $queryBuilder->getQuery();
+
+        $this->assertEquals(
+            $query->getDQL(),
+            sprintf('SELECT t FROM %s t WHERE t.expireAt < :date', $this->tokenRepository->getClassName())
+        );
+    }
+}
diff --git a/src/Majora/Component/OAuth/Tests/Repository/ORM/AccessTokenRepositoryTest.php b/src/Majora/Component/OAuth/Tests/Repository/ORM/AccessTokenRepositoryTest.php
new file mode 100644
index 0000000..563a533
--- /dev/null
+++ b/src/Majora/Component/OAuth/Tests/Repository/ORM/AccessTokenRepositoryTest.php
@@ -0,0 +1,54 @@
+<?php
+
+namespace Majora\Component\OAuth\Repository\Loader\ORM;
+
+use Doctrine\ORM\EntityManagerInterface;
+use Doctrine\ORM\Mapping\ClassMetadata;
+use Majora\Component\OAuth\Entity\AccessToken;
+use Majora\Component\OAuth\Repository\ORM\AccessTokenRepository;
+
+/**
+ * Unit tests class for Majora\Component\OAuth\Repository\ORM\AccessTokenRepository.
+ *
+ * @see Majora\Component\OAuth\Repository\ORM\AccessTokenRepository
+ */
+class AccessTokenRepositoryTest extends \PHPUnit_Framework_TestCase
+{
+    /**
+     * Tests persist() method.
+     */
+    public function testPersist()
+    {
+        $token = $this->prophesize(AccessToken::class)->reveal();
+        $em = $this->prophesize(EntityManagerInterface::class);
+
+        $em->persist($token)->shouldBeCalled();
+        $em->flush()->shouldBeCalled();
+
+        $repository = new AccessTokenRepository(
+            $em->reveal(),
+            new ClassMetadata(AccessToken::class)
+        );
+
+        $repository->persist($token);
+    }
+
+    /**
+     * Tests remove() method.
+     */
+    public function testRemove()
+    {
+        $token = $this->prophesize(AccessToken::class)->reveal();
+        $em = $this->prophesize(EntityManagerInterface::class);
+
+        $em->remove($token)->shouldBeCalled();
+        $em->flush()->shouldBeCalled();
+
+        $repository = new AccessTokenRepository(
+            $em->reveal(),
+            new ClassMetadata(AccessToken::class)
+        );
+
+        $repository->remove($token);
+    }
+}
diff --git a/src/Majora/Component/OAuth/Tests/Repository/ORM/AccountRepositoryTest.php b/src/Majora/Component/OAuth/Tests/Repository/ORM/AccountRepositoryTest.php
new file mode 100644
index 0000000..92e1be2
--- /dev/null
+++ b/src/Majora/Component/OAuth/Tests/Repository/ORM/AccountRepositoryTest.php
@@ -0,0 +1,54 @@
+<?php
+
+namespace Majora\Component\OAuth\Repository\Loader\ORM;
+
+use Doctrine\ORM\EntityManagerInterface;
+use Doctrine\ORM\Mapping\ClassMetadata;
+use Majora\Component\OAuth\Entity\Account;
+use Majora\Component\OAuth\Repository\ORM\AccountRepository;
+
+/**
+ * Unit tests class for Majora\Component\OAuth\Repository\ORM\AccountRepository.
+ *
+ * @see Majora\Component\OAuth\Repository\ORM\AccountRepository
+ */
+class AccountRepositoryTest extends \PHPUnit_Framework_TestCase
+{
+    /**
+     * Tests persist() method.
+     */
+    public function testPersist()
+    {
+        $account = new Account();
+        $em = $this->prophesize(EntityManagerInterface::class);
+
+        $em->persist($account)->shouldBeCalled();
+        $em->flush()->shouldBeCalled();
+
+        $repository = new AccountRepository(
+            $em->reveal(),
+            new ClassMetadata(Account::class)
+        );
+
+        $repository->persist($account);
+    }
+
+    /**
+     * Tests remove() method.
+     */
+    public function testRemove()
+    {
+        $account = new Account();
+        $em = $this->prophesize(EntityManagerInterface::class);
+
+        $em->remove($account)->shouldBeCalled();
+        $em->flush()->shouldBeCalled();
+
+        $repository = new AccountRepository(
+            $em->reveal(),
+            new ClassMetadata(Account::class)
+        );
+
+        $repository->remove($account);
+    }
+}
diff --git a/src/Majora/Component/OAuth/Tests/Repository/ORM/ApplicationRepositoryTest.php b/src/Majora/Component/OAuth/Tests/Repository/ORM/ApplicationRepositoryTest.php
new file mode 100644
index 0000000..4672dc7
--- /dev/null
+++ b/src/Majora/Component/OAuth/Tests/Repository/ORM/ApplicationRepositoryTest.php
@@ -0,0 +1,54 @@
+<?php
+
+namespace Majora\Component\OAuth\Repository\Loader\ORM;
+
+use Doctrine\ORM\EntityManagerInterface;
+use Doctrine\ORM\Mapping\ClassMetadata;
+use Majora\Component\OAuth\Entity\Application;
+use Majora\Component\OAuth\Repository\ORM\ApplicationRepository;
+
+/**
+ * Unit tests class for Majora\Component\OAuth\Repository\ORM\ApplicationRepository.
+ *
+ * @see Majora\Component\OAuth\Repository\ORM\ApplicationRepository
+ */
+class ApplicationRepositoryTest extends \PHPUnit_Framework_TestCase
+{
+    /**
+     * Tests persist() method.
+     */
+    public function testPersist()
+    {
+        $application = new Application();
+        $em = $this->prophesize(EntityManagerInterface::class);
+
+        $em->persist($application)->shouldBeCalled();
+        $em->flush()->shouldBeCalled();
+
+        $repository = new ApplicationRepository(
+            $em->reveal(),
+            new ClassMetadata(Application::class)
+        );
+
+        $repository->persist($application);
+    }
+
+    /**
+     * Tests remove() method.
+     */
+    public function testRemove()
+    {
+        $application = new Application();
+        $em = $this->prophesize(EntityManagerInterface::class);
+
+        $em->remove($application)->shouldBeCalled();
+        $em->flush()->shouldBeCalled();
+
+        $repository = new ApplicationRepository(
+            $em->reveal(),
+            new ClassMetadata(Application::class)
+        );
+
+        $repository->remove($application);
+    }
+}
diff --git a/src/Majora/Component/OAuth/Tests/Repository/ORM/RefreshTokenRepositoryTest.php b/src/Majora/Component/OAuth/Tests/Repository/ORM/RefreshTokenRepositoryTest.php
new file mode 100644
index 0000000..984b076
--- /dev/null
+++ b/src/Majora/Component/OAuth/Tests/Repository/ORM/RefreshTokenRepositoryTest.php
@@ -0,0 +1,54 @@
+<?php
+
+namespace Majora\Component\OAuth\Repository\Loader\ORM;
+
+use Doctrine\ORM\EntityManagerInterface;
+use Doctrine\ORM\Mapping\ClassMetadata;
+use Majora\Component\OAuth\Entity\RefreshToken;
+use Majora\Component\OAuth\Repository\ORM\RefreshTokenRepository;
+
+/**
+ * Unit tests class for Majora\Component\OAuth\Repository\ORM\RefreshTokenRepository.
+ *
+ * @see Majora\Component\OAuth\Repository\ORM\RefreshTokenRepository
+ */
+class RefreshTokenRepositoryTest extends \PHPUnit_Framework_TestCase
+{
+    /**
+     * Tests persist() method.
+     */
+    public function testPersist()
+    {
+        $token = $this->prophesize(RefreshToken::class)->reveal();
+        $em = $this->prophesize(EntityManagerInterface::class);
+
+        $em->persist($token)->shouldBeCalled();
+        $em->flush()->shouldBeCalled();
+
+        $repository = new RefreshTokenRepository(
+            $em->reveal(),
+            new ClassMetadata(RefreshToken::class)
+        );
+
+        $repository->persist($token);
+    }
+
+    /**
+     * Tests remove() method.
+     */
+    public function testRemove()
+    {
+        $token = $this->prophesize(RefreshToken::class)->reveal();
+        $em = $this->prophesize(EntityManagerInterface::class);
+
+        $em->remove($token)->shouldBeCalled();
+        $em->flush()->shouldBeCalled();
+
+        $repository = new RefreshTokenRepository(
+            $em->reveal(),
+            new ClassMetadata(RefreshToken::class)
+        );
+
+        $repository->remove($token);
+    }
+}