diff --git a/.State b/.State
deleted file mode 100644
index a604de4..0000000
--- a/.State
+++ /dev/null
@@ -1 +0,0 @@
-finalized
diff --git a/Acl.php b/Source/Acl.php
similarity index 78%
rename from Acl.php
rename to Source/Acl.php
index bc7d543..a7d8cfb 100644
--- a/Acl.php
+++ b/Source/Acl.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * Hoa
  *
@@ -45,9 +47,6 @@
  * The ACL main class. It contains all users, groups, and services collections.
  * It also proposes to check if a user is allow or not to do an action according
  * to its groups and services.
- *
- * @copyright  Copyright © 2007-2017 Hoa community
- * @license    New BSD License
  */
 class Acl
 {
@@ -75,7 +74,7 @@ class Acl
     /**
      * Underlying graph.
      *
-     * @var \Hoa\Graph
+     * @var ?Graph
      */
     protected $_groups   = null;
 
@@ -100,20 +99,14 @@ public function __construct()
 
     /**
      * Add a group, i.e. add a node in the underlying graph.
-     *
-     * @param   \Hoa\Acl\Group  $group      Group to add.
-     * @param   array           $parents    Parent groups (will inherit
-     *                                      permissions).
-     * @return  \Hoa\Acl\Acl
-     * @throws  \Hoa\Acl\Exception
      */
-    public function addGroup(Group $group, array $parents = [])
+    public function addGroup(Group $group, array $parents = []): self
     {
         foreach ($parents as $parent) {
             if (!($parent instanceof Group)) {
                 throw new Exception(
                     'Group %s must be an instance of Hoa\Acl\Group.',
-                    1,
+                    0,
                     $parent
                 );
             }
@@ -130,13 +123,8 @@ public function addGroup(Group $group, array $parents = [])
 
     /**
      * Delete a group, i.e. delete a node in the underlying graph.
-     *
-     * @param   \Hoa\Acl\Group  $group        Group.
-     * @param   bool            $propagate    Propagate the erasure.
-     * @return  \Hoa\Acl\Acl
-     * @throws  \Hoa\Acl\Exception
      */
-    public function deleteGroup(Group $group, $propagate = self::DELETE_RESTRICT)
+    public function deleteGroup(Group $group, bool $propagate = self::DELETE_RESTRICT): self
     {
         try {
             $this->getGroups()->deleteNode($group, $propagate);
@@ -144,7 +132,7 @@ public function deleteGroup(Group $group, $propagate = self::DELETE_RESTRICT)
             throw new Exception(
                 'Apparently it is not possible to delete the group %s, ' .
                 'probably because it has at least one child.',
-                42,
+                1,
                 $group->getId(),
                 $e
             );
@@ -156,26 +144,19 @@ public function deleteGroup(Group $group, $propagate = self::DELETE_RESTRICT)
     /**
      * Check if a group exists or not, i.e. if a node in the underlying graph
      * exists.
-     *
-     * @param   mixed  $groupId    Group ID.
-     * @return  bool
      */
-    public function groupExists($groupId)
+    public function groupExists($groupId): bool
     {
         return $this->getGroups()->nodeExists($groupId);
     }
 
     /**
      * Get a specific group, i.e. a specific node in the underlying graph.
-     *
-     * @param   string  $groupId    Group ID.
-     * @return  \Hoa\Acl\Group
-     * @throws  \Hoa\Acl\Exception
      */
-    protected function getGroup($groupId)
+    protected function getGroup(string $groupId): Group
     {
         if (false === $this->groupExists($groupId)) {
-            throw new Exception('Group %s does not exist.', 6, $groupId);
+            throw new Exception('Group %s does not exist.', 2, $groupId);
         }
 
         return $this->getGroups()->getNode($groupId);
@@ -183,23 +164,16 @@ protected function getGroup($groupId)
 
     /**
      * Get all groups, i.e. get the underlying graph.
-     *
-     * @return  \Hoa\Graph
      */
-    protected function getGroups()
+    protected function getGroups(): Graph
     {
         return $this->_groups;
     }
 
     /**
      * Attach one or more permissions to a group.
-     *
-     * @param   Group  $group          Group.
-     * @param   array  $permissions    Collection of permissions.
-     * @return  \Hoa\Acl\Acl
-     * @throws  \Hoa\Acl\Exception
      */
-    public function allow(Group $group, array $permissions = [])
+    public function allow(Group $group, array $permissions = []): self
     {
         $id = $group->getId();
 
@@ -207,7 +181,7 @@ public function allow(Group $group, array $permissions = [])
             throw new Exception(
                 'Group %s is not declared in the current ACL instance, ' .
                 'cannot add permissions.',
-                2,
+                3,
                 $id
             );
         }
@@ -219,13 +193,8 @@ public function allow(Group $group, array $permissions = [])
 
     /**
      * Detach one or more permission to a group.
-     *
-     * @param   Group  $group          Group.
-     * @param   array  $permissions    Collection of permissions.
-     * @return  \Hoa\Acl\Acl
-     * @throws  \Hoa\Acl\Exception
      */
-    public function deny(Group $group, array $permissions = [])
+    public function deny(Group $group, array $permissions = []): self
     {
         $id = $group->getId();
 
@@ -233,7 +202,7 @@ public function deny(Group $group, array $permissions = [])
             throw new Exception(
                 'Group %s is not declared in the current ACL instance, ' .
                 'cannot delete permissions.',
-                3,
+                4,
                 $id
             );
         }
@@ -245,20 +214,13 @@ public function deny(Group $group, array $permissions = [])
 
     /**
      * Check if a user is allowed to do something according to the permission.
-     *
-     * @param   mixed               $userId          User ID (or instance).
-     * @param   mixed               $permissionId    Permission ID (or instance).
-     * @param   mixed               $serviceId       Service ID (or instance).
-     * @param   Hoa\Acl\Assertable  $assert          Assert.
-     * @return  bool
-     * @throws  \Hoa\Acl\Exception
      */
     public function isAllowed(
         $userId,
         $permissionId,
         $serviceId         = null,
         Assertable $assert = null
-    ) {
+    ): bool {
         if ($userId instanceof User) {
             $userId = $userId->getId();
         }
@@ -333,10 +295,8 @@ public function isAllowed(
 
     /**
      * Transform the groups to DOT language.
-     *
-     * @return  string
      */
-    public function __toString()
+    public function __toString(): string
     {
         return $this->getGroups()->__toString();
     }
@@ -345,4 +305,4 @@ public function __toString()
 /**
  * Flex entity.
  */
-Consistency::flexEntity('Hoa\Acl\Acl');
+Consistency::flexEntity(Acl::class);
diff --git a/Assertable.php b/Source/Assertable.php
similarity index 84%
rename from Assertable.php
rename to Source/Assertable.php
index e1fe74b..62ecea4 100644
--- a/Assertable.php
+++ b/Source/Assertable.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * Hoa
  *
@@ -40,9 +42,6 @@
  * Interface \Hoa\Acl\Assertable.
  *
  * Force to implement the assert method.
- *
- * @copyright  Copyright © 2007-2017 Hoa community
- * @license    New BSD License
  */
 interface Assertable
 {
@@ -50,11 +49,6 @@ interface Assertable
      * Write an assert.
      * Must return a boolean, because the comparison will be strict (using
      * ===).
-     *
-     * @param   string  $userId          User ID.
-     * @param   string  $permissionId    Permission ID.
-     * @param   string  $serviceId       Service ID (can be null).
-     * @return  bool
      */
-    public function assert($userId, $permissionId, $serviceId);
+    public function assert(string $userId, string $permissionId, string $serviceId): bool;
 }
diff --git a/Exception.php b/Source/Exception.php
similarity index 95%
rename from Exception.php
rename to Source/Exception.php
index 1aec480..852d955 100644
--- a/Exception.php
+++ b/Source/Exception.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * Hoa
  *
@@ -42,9 +44,6 @@
  * Class \Hoa\Acl\Exception.
  *
  * Extending the \Hoa\Exception\Exception class.
- *
- * @copyright  Copyright © 2007-2017 Hoa community
- * @license    New BSD License
  */
 class Exception extends HoaException
 {
diff --git a/Group.php b/Source/Group.php
similarity index 75%
rename from Group.php
rename to Source/Group.php
index 946cdb3..1258017 100644
--- a/Group.php
+++ b/Source/Group.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * Hoa
  *
@@ -46,9 +48,6 @@
  * `Hoa\Graph`) and thus can inherit permissions from other groups. Users and
  * services cannot be inherited. If a group owns a service, this is a shared
  * service because several users can access to it.
- *
- * @copyright  Copyright © 2007-2017 Hoa community
- * @license    New BSD License
  */
 class Group implements Graph\Node
 {
@@ -62,7 +61,7 @@ class Group implements Graph\Node
     /**
      * Group label.
      *
-     * @var string
+     * @var ?string
      */
     protected $_label       = null;
 
@@ -91,11 +90,8 @@ class Group implements Graph\Node
 
     /**
      * Built a new group.
-     *
-     * @param   mixed   $id       The group ID.
-     * @param   string  $label    The group label.
      */
-    public function __construct($id, $label = null)
+    public function __construct($id, ?string $label = null)
     {
         $this->setId($id);
         $this->setLabel($label);
@@ -105,12 +101,8 @@ public function __construct($id, $label = null)
 
     /**
      * Add users.
-     *
-     * @param   array  $users    Users to add.
-     * @return  \Hoa\Acl\Group
-     * @throws  \Hoa\Acl\Exception
      */
-    public function addUsers(array $users = [])
+    public function addUsers(array $users = []): self
     {
         foreach ($users as $user) {
             if (!($user instanceof User)) {
@@ -135,12 +127,8 @@ public function addUsers(array $users = [])
 
     /**
      * Delete users.
-     *
-     * @param   array  $users    User to add.
-     * @return  \Hoa\Acl\Group
-     * @throws  \Hoa\Acl\Exception
      */
-    public function deleteUsers(array $users = [])
+    public function deleteUsers(array $users = []): self
     {
         foreach ($users as $user) {
             if (!($user instanceof User)) {
@@ -165,11 +153,8 @@ public function deleteUsers(array $users = [])
 
     /**
      * Check if a user exists or not.
-     *
-     * @param   muxed  $userId    User ID (or instance).
-     * @return  bool
      */
-    public function userExists($userId)
+    public function userExists($userId): bool
     {
         if ($userId instanceof User) {
             $userId = $userId->getId();
@@ -180,12 +165,8 @@ public function userExists($userId)
 
     /**
      * Get a specific user.
-     *
-     * @param   string  $userId    User ID.
-     * @return  \Hoa\Acl\User
-     * @throws  \Hoa\Acl\Exception
      */
-    public function getUser($userId)
+    public function getUser(string $userId): User
     {
         if (false === $this->userExists($userId)) {
             throw new Exception('User %s does not exist.', 2, $userId);
@@ -196,22 +177,16 @@ public function getUser($userId)
 
     /**
      * Get all users.
-     *
-     * @return  array
      */
-    public function getUsers()
+    public function getUsers(): array
     {
         return $this->_users;
     }
 
     /**
      * Add permissions in this group.
-     *
-     * @param   array  $permissions    Permissions to add.
-     * @return  \Hoa\Acl\Group
-     * @throws  \Hoa\Acl\Exception
      */
-    public function addPermissions(array $permissions = [])
+    public function addPermissions(array $permissions = []): self
     {
         foreach ($permissions as $permission) {
             if (!($permission instanceof Permission)) {
@@ -236,12 +211,8 @@ public function addPermissions(array $permissions = [])
 
     /**
      * Delete permissions in this group.
-     *
-     * @param   array  $permissions    Permissions to add.
-     * @return  \Hoa\Acl\Group
-     * @throws  \Hoa\Acl\Exception
      */
-    public function deletePermissions(array $permissions = [])
+    public function deletePermissions(array $permissions = []): self
     {
         foreach ($permissions as $permission) {
             if (!($permission instanceof Permission)) {
@@ -266,23 +237,16 @@ public function deletePermissions(array $permissions = [])
 
     /**
      * Check if a permission exists in this group.
-     *
-     * @param   mixed  $permissionId    Permission ID.
-     * @return  bool
      */
-    public function permissionExists($permissionId)
+    public function permissionExists($permissionId): bool
     {
         return isset($this->_permissions[$permissionId]);
     }
 
     /**
      * Get a specific permission of this group.
-     *
-     * @param   mixed  $permissionId    Permission ID.
-     * @return  \Hoa\Acl\Permission
-     * @throws  \Hoa\Acl\Exception
      */
-    public function getPermission($permissionId)
+    public function getPermission($permissionId): Permission
     {
         if (false === $this->permissionExists($permissionId)) {
             throw new Exception(
@@ -297,22 +261,16 @@ public function getPermission($permissionId)
 
     /**
      * Get permissions of this group.
-     *
-     * @return  array
      */
-    public function getPermissions()
+    public function getPermissions(): array
     {
         return $this->_permissions;
     }
 
     /**
      * Add shared services.
-     *
-     * @param   array  $services    Services to add.
-     * @return  \Hoa\Acl\Group
-     * @throws  \Hoa\Acl\Exception
      */
-    public function addServices(array $services = [])
+    public function addServices(array $services = []): self
     {
         foreach ($services as $service) {
             if (!($service instanceof Service)) {
@@ -337,12 +295,8 @@ public function addServices(array $services = [])
 
     /**
      * Delete shared services.
-     *
-     * @param   array  $services    Service to add.
-     * @return  \Hoa\Acl\Group
-     * @throws  \Hoa\Acl\Exception
      */
-    public function deleteServices(array $services = [])
+    public function deleteServices(array $services = []): self
     {
         foreach ($services as $service) {
             if (!($service instanceof Service)) {
@@ -367,11 +321,8 @@ public function deleteServices(array $services = [])
 
     /**
      * Check if a shared service exists or not.
-     *
-     * @param   muxed  $serviceId    Service ID (or instance).
-     * @return  bool
      */
-    public function serviceExists($serviceId)
+    public function serviceExists($serviceId): bool
     {
         if ($serviceId instanceof Service) {
             $serviceId = $serviceId->getId();
@@ -382,12 +333,8 @@ public function serviceExists($serviceId)
 
     /**
      * Get a specific shared service.
-     *
-     * @param   string  $serviceId    Service ID.
-     * @return  \Hoa\Acl\Service
-     * @throws  \Hoa\Acl\Exception
      */
-    protected function getService($serviceId)
+    protected function getService(string $serviceId): Service
     {
         if (false === $this->serviceExists($serviceId)) {
             throw new Exception('Service %s does not exist.', 8, $serviceId);
@@ -398,19 +345,14 @@ protected function getService($serviceId)
 
     /**
      * Get all shared services.
-     *
-     * @return  array
      */
-    protected function getServices()
+    protected function getServices(): array
     {
         return $this->_services;
     }
 
     /**
      * Set group ID.
-     *
-     * @param   mixed  $id    Group ID.
-     * @return  mixed
      */
     protected function setId($id)
     {
@@ -422,8 +364,6 @@ protected function setId($id)
 
     /**
      * Get group ID.
-     *
-     * @return  mixed
      */
     public function getId()
     {
@@ -432,11 +372,8 @@ public function getId()
 
     /**
      * Set group label.
-     *
-     * @param   string  $label    Group label.
-     * @return  string
      */
-    public function setLabel($label)
+    public function setLabel(?string $label): ?string
     {
         $old          = $this->_label;
         $this->_label = $label;
@@ -446,18 +383,14 @@ public function setLabel($label)
 
     /**
      * Get group label.
-     *
-     * @return  mixed
      */
-    public function getLabel()
+    public function getLabel(): ?string
     {
         return $this->_label;
     }
 
     /**
      * Get node ID, i.e. group ID (see `Hoa\Graph\IGraph\Node`).
-     *
-     * @return  mixed
      */
     public function getNodeId()
     {
diff --git a/Permission.php b/Source/Permission.php
similarity index 83%
rename from Permission.php
rename to Source/Permission.php
index bde73a1..db179ed 100644
--- a/Permission.php
+++ b/Source/Permission.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * Hoa
  *
@@ -41,9 +43,6 @@
  *
  * A permission is a right. A group holds zero or more permissions that can be
  * used to allow or disallow access to something.
- *
- * @copyright  Copyright © 2007-2017 Hoa community
- * @license    New BSD License
  */
 class Permission
 {
@@ -57,7 +56,7 @@ class Permission
     /**
      * Permission label.
      *
-     * @var string
+     * @var ?string
      */
     protected $_label = null;
 
@@ -65,11 +64,8 @@ class Permission
 
     /**
      * Built a new permission.
-     *
-     * @param   mixed   $id       Permission ID.
-     * @param   string  $label    Permission label.
      */
-    public function __construct($id, $label = null)
+    public function __construct($id, ?string $label = null)
     {
         $this->setId($id);
         $this->setLabel($label);
@@ -79,9 +75,6 @@ public function __construct($id, $label = null)
 
     /**
      * Set permission ID.
-     *
-     * @param   mixed  $id    Permission ID.
-     * @return  mixed
      */
     protected function setId($id)
     {
@@ -93,8 +86,6 @@ protected function setId($id)
 
     /**
      * Get permission ID.
-     *
-     * @return  mixed
      */
     public function getId()
     {
@@ -103,11 +94,8 @@ public function getId()
 
     /**
      * Set permission label.
-     *
-     * @param   string  $label    Permission label.
-     * @return  string
      */
-    public function setLabel($label)
+    public function setLabel(?string $label): ?string
     {
         $old          = $this->_label;
         $this->_label = $label;
@@ -117,10 +105,8 @@ public function setLabel($label)
 
     /**
      * Get permission label.
-     *
-     * @return  mixed
      */
-    public function getLabel()
+    public function getLabel(): ?string
     {
         return $this->_label;
     }
diff --git a/Service.php b/Source/Service.php
similarity index 83%
rename from Service.php
rename to Source/Service.php
index fc5a346..54c6ef4 100644
--- a/Service.php
+++ b/Source/Service.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * Hoa
  *
@@ -41,9 +43,6 @@
  *
  * A services is a document, a resource, something a user would like to
  * access.
- *
- * @copyright  Copyright © 2007-2017 Hoa community
- * @license    New BSD License
  */
 class Service
 {
@@ -57,7 +56,7 @@ class Service
     /**
      * Service label.
      *
-     * @var string
+     * @var ?string
      */
     protected $_label = null;
 
@@ -65,11 +64,8 @@ class Service
 
     /**
      * Built a new service.
-     *
-     * @param   mixed   $id       Service ID.
-     * @param   string  $label    Service label.
      */
-    public function __construct($id, $label = null)
+    public function __construct($id, ?string $label = null)
     {
         $this->setId($id);
         $this->setLabel($label);
@@ -79,9 +75,6 @@ public function __construct($id, $label = null)
 
     /**
      * Set service ID.
-     *
-     * @param   mixed  $id    Service ID.
-     * @return  mixed
      */
     protected function setId($id)
     {
@@ -93,8 +86,6 @@ protected function setId($id)
 
     /**
      * Get service ID.
-     *
-     * @return  mixed
      */
     public function getId()
     {
@@ -103,11 +94,8 @@ public function getId()
 
     /**
      * Set service label.
-     *
-     * @param   string  $label    Service label.
-     * @return  string
      */
-    public function setLabel($label)
+    public function setLabel(?string $label): ?string
     {
         $old          = $this->_label;
         $this->_label = $label;
@@ -117,10 +105,8 @@ public function setLabel($label)
 
     /**
      * Get service label.
-     *
-     * @return  mixed
      */
-    public function getLabel()
+    public function getLabel(): ?string
     {
         return $this->_label;
     }
diff --git a/User.php b/Source/User.php
similarity index 77%
rename from User.php
rename to Source/User.php
index d0f52d9..48648ef 100644
--- a/User.php
+++ b/Source/User.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * Hoa
  *
@@ -41,9 +43,6 @@
  *
  * A user is a role —an actor— that can own zero or more services and can belong
  * to zero or more groups.
- *
- * @copyright  Copyright © 2007-2017 Hoa community
- * @license    New BSD License
  */
 class User
 {
@@ -57,7 +56,7 @@ class User
     /**
      * User label.
      *
-     * @var string
+     * @var ?string
      */
     protected $_label    = null;
 
@@ -72,11 +71,8 @@ class User
 
     /**
      * Built a new user.
-     *
-     * @param   mixed   $id       The user ID.
-     * @param   string  $label    The user label.
      */
-    public function __construct($id, $label = null)
+    public function __construct($id, ?string $label = null)
     {
         $this->setId($id);
         $this->setLabel($label);
@@ -86,12 +82,8 @@ public function __construct($id, $label = null)
 
     /**
      * Add services.
-     *
-     * @param   array  $services    Services to add.
-     * @return  \Hoa\Acl\User
-     * @throws  \Hoa\Acl\Exception
      */
-    public function addServices(array $services = [])
+    public function addServices(array $services = []): self
     {
         foreach ($services as $service) {
             if (!($service instanceof Service)) {
@@ -116,12 +108,8 @@ public function addServices(array $services = [])
 
     /**
      * Delete services.
-     *
-     * @param   array  $services    Service to add.
-     * @return  \Hoa\Acl\User
-     * @throws  \Hoa\Acl\Exception
      */
-    public function deleteServices(array $services = [])
+    public function deleteServices(array $services = []): self
     {
         foreach ($services as $service) {
             if (!($service instanceof Service)) {
@@ -146,11 +134,8 @@ public function deleteServices(array $services = [])
 
     /**
      * Check if a service exists or not.
-     *
-     * @param   muxed  $serviceId    Service ID (or instance).
-     * @return  bool
      */
-    public function serviceExists($serviceId)
+    public function serviceExists($serviceId): bool
     {
         if ($serviceId instanceof Service) {
             $serviceId = $serviceId->getId();
@@ -161,12 +146,8 @@ public function serviceExists($serviceId)
 
     /**
      * Get a specific service.
-     *
-     * @param   string  $serviceId    Service ID.
-     * @return  \Hoa\Acl\Service
-     * @throws  \Hoa\Acl\Exception
      */
-    protected function getService($serviceId)
+    protected function getService(string $serviceId): Service
     {
         if (false === $this->serviceExists($serviceId)) {
             throw new Exception('Service %s does not exist.', 2, $serviceId);
@@ -177,19 +158,14 @@ protected function getService($serviceId)
 
     /**
      * Get all services.
-     *
-     * @return  array
      */
-    protected function getServices()
+    protected function getServices() : array
     {
         return $this->_services;
     }
 
     /**
      * Set user ID.
-     *
-     * @param   mixed  $id    User ID.
-     * @return  mixed
      */
     protected function setId($id)
     {
@@ -201,8 +177,6 @@ protected function setId($id)
 
     /**
      * Get user ID.
-     *
-     * @return  mixed
      */
     public function getId()
     {
@@ -211,11 +185,8 @@ public function getId()
 
     /**
      * Set user label.
-     *
-     * @param   string  $label    User label.
-     * @return  string
      */
-    public function setLabel($label)
+    public function setLabel(?string $label): ?string
     {
         $old          = $this->_label;
         $this->_label = $label;
@@ -225,10 +196,8 @@ public function setLabel($label)
 
     /**
      * Get user label.
-     *
-     * @return  mixed
      */
-    public function getLabel()
+    public function getLabel(): ?string
     {
         return $this->_label;
     }
diff --git a/Test/Integration/Documentation.php b/Test/Integration/Documentation.php
index d05d108..097c95d 100644
--- a/Test/Integration/Documentation.php
+++ b/Test/Integration/Documentation.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * Hoa
  *
diff --git a/Test/Unit/Acl.php b/Test/Unit/Acl.php
index bb37251..26655d1 100644
--- a/Test/Unit/Acl.php
+++ b/Test/Unit/Acl.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * Hoa
  *
@@ -45,9 +47,6 @@
  * Class \Hoa\Acl\Test\Unit\Acl.
  *
  * Test suite of the ACL class.
- *
- * @copyright  Copyright © 2007-2017 Hoa community
- * @license    New BSD License
  */
 class Acl extends Test\Unit\Suite
 {
diff --git a/Test/Unit/Assertable.php b/Test/Unit/Assertable.php
index 1cc4396..fccaed4 100644
--- a/Test/Unit/Assertable.php
+++ b/Test/Unit/Assertable.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * Hoa
  *
@@ -43,9 +45,6 @@
  * Class \Hoa\Acl\Test\Unit\Assertable.
  *
  * Test suite of the assertable interface.
- *
- * @copyright  Copyright © 2007-2017 Hoa community
- * @license    New BSD License
  */
 class Assertable extends Test\Unit\Suite
 {
diff --git a/Test/Unit/Exception.php b/Test/Unit/Exception.php
index 71e24ed..01f61c1 100644
--- a/Test/Unit/Exception.php
+++ b/Test/Unit/Exception.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * Hoa
  *
@@ -44,9 +46,6 @@
  * Class \Hoa\Acl\Test\Unit\Exception.
  *
  * Test suite of the exception.
- *
- * @copyright  Copyright © 2007-2017 Hoa community
- * @license    New BSD License
  */
 class Exception extends Test\Unit\Suite
 {
diff --git a/Test/Unit/Group.php b/Test/Unit/Group.php
index babcbdf..d3f054d 100644
--- a/Test/Unit/Group.php
+++ b/Test/Unit/Group.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * Hoa
  *
@@ -45,9 +47,6 @@
  * Class \Hoa\Acl\Test\Unit\Group.
  *
  * Test suite of the group class.
- *
- * @copyright  Copyright © 2007-2017 Hoa community
- * @license    New BSD License
  */
 class Group extends Test\Unit\Suite
 {
diff --git a/Test/Unit/Permission.php b/Test/Unit/Permission.php
index 3fba8df..b8f0f0a 100644
--- a/Test/Unit/Permission.php
+++ b/Test/Unit/Permission.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * Hoa
  *
@@ -44,9 +46,6 @@
  * Class \Hoa\Acl\Test\Unit\Permission.
  *
  * Test suite of the permission class.
- *
- * @copyright  Copyright © 2007-2017 Hoa community
- * @license    New BSD License
  */
 class Permission extends Test\Unit\Suite
 {
diff --git a/Test/Unit/Service.php b/Test/Unit/Service.php
index 064f05c..e3e8c70 100644
--- a/Test/Unit/Service.php
+++ b/Test/Unit/Service.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * Hoa
  *
@@ -43,9 +45,6 @@
  * Class \Hoa\Acl\Test\Unit\Service.
  *
  * Test suite of the service class.
- *
- * @copyright  Copyright © 2007-2017 Hoa community
- * @license    New BSD License
  */
 class Service extends Test\Unit\Suite
 {
diff --git a/Test/Unit/User.php b/Test/Unit/User.php
index 25b5c49..b4ef1d9 100644
--- a/Test/Unit/User.php
+++ b/Test/Unit/User.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 /**
  * Hoa
  *
@@ -44,9 +46,6 @@
  * Class \Hoa\Acl\Test\Unit\User.
  *
  * Test suite of the user class.
- *
- * @copyright  Copyright © 2007-2017 Hoa community
- * @license    New BSD License
  */
 class User extends Test\Unit\Suite
 {
diff --git a/composer.json b/composer.json
index fd1430e..3545066 100644
--- a/composer.json
+++ b/composer.json
@@ -24,17 +24,18 @@
         "source": "https://central.hoa-project.net/Resource/Library/Acl"
     },
     "require": {
-        "php"            : ">=5.5.0",
-        "hoa/consistency": "~1.0",
-        "hoa/exception"  : "~1.0",
-        "hoa/graph"      : "~1.0"
+        "php"            : ">=7.1",
+        "hoa/consistency": "dev-master",
+        "hoa/exception"  : "dev-master",
+        "hoa/graph"      : "dev-master"
     },
     "require-dev": {
-        "hoa/test": "~2.0"
+        "hoa/test": "dev-master"
     },
     "autoload": {
         "psr-4": {
-            "Hoa\\Acl\\": "."
+            "Hoa\\Acl\\"      : "Source",
+            "Hoa\\Acl\\Test\\": "Test"
         }
     },
     "extra": {