diff --git a/src/Module/Core/Infrastructure/Console/CreateUserCommand.php b/src/Module/Core/Infrastructure/Console/CreateUserCommand.php
index 7133adc..f13afeb 100644
--- a/src/Module/Core/Infrastructure/Console/CreateUserCommand.php
+++ b/src/Module/Core/Infrastructure/Console/CreateUserCommand.php
@@ -5,7 +5,9 @@ declare(strict_types=1);
 namespace App\Module\Core\Infrastructure\Console;
 
 use App\Module\Core\Domain\Entity\User;
+use App\Module\Core\Domain\Repository\RoleRepositoryInterface;
 use App\Module\Core\Domain\Repository\UserRepositoryInterface;
+use App\Module\Core\Domain\Security\SystemRoles;
 use Symfony\Component\Console\Attribute\AsCommand;
 use Symfony\Component\Console\Command\Command;
 use Symfony\Component\Console\Input\InputArgument;
@@ -17,13 +19,14 @@ use Symfony\Component\PasswordHasher\Hasher\UserPasswordHasherInterface;
 
 #[AsCommand(
     name: 'app:create-user',
-    description: 'Create a new user',
+    description: 'Cree un utilisateur rattache au role systeme admin ou user.',
 )]
-class CreateUserCommand extends Command
+final class CreateUserCommand extends Command
 {
     public function __construct(
         private readonly UserRepositoryInterface $userRepository,
         private readonly UserPasswordHasherInterface $passwordHasher,
+        private readonly RoleRepositoryInterface $roleRepository,
     ) {
         parent::__construct();
     }
@@ -31,9 +34,9 @@ class CreateUserCommand extends Command
     protected function configure(): void
     {
         $this
-            ->addArgument('username', InputArgument::REQUIRED, 'Username')
-            ->addArgument('password', InputArgument::REQUIRED, 'Plain password')
-            ->addOption('admin', null, InputOption::VALUE_NONE, 'Grant ROLE_ADMIN')
+            ->addArgument('username', InputArgument::REQUIRED, 'Nom d\'utilisateur')
+            ->addArgument('password', InputArgument::REQUIRED, 'Mot de passe en clair')
+            ->addOption('admin', null, InputOption::VALUE_NONE, 'Rattache au role systeme admin + active is_admin')
         ;
     }
 
@@ -43,19 +46,34 @@ class CreateUserCommand extends Command
 
         $username      = $input->getArgument('username');
         $plainPassword = $input->getArgument('password');
+        $isAdmin       = (bool) $input->getOption('admin');
+
+        $roleCode = $isAdmin ? SystemRoles::ADMIN_CODE : SystemRoles::USER_CODE;
+        $role     = $this->roleRepository->findByCode($roleCode);
+
+        if (null === $role) {
+            $io->error(sprintf(
+                'Le role systeme "%s" est introuvable. Lance "bin/console doctrine:migrations:migrate" pour le seeder.',
+                $roleCode,
+            ));
+
+            return Command::FAILURE;
+        }
 
         $user = new User();
         $user->setUsername($username);
         $user->setPassword($this->passwordHasher->hashPassword($user, $plainPassword));
-
-        if ($input->getOption('admin')) {
-            // TODO Task 6 : attacher l'entite Role "admin" en plus du flag is_admin.
-            $user->setIsAdmin(true);
-        }
+        $user->setIsAdmin($isAdmin);
+        $user->addRbacRole($role);
 
         $this->userRepository->save($user);
 
-        $io->success(sprintf('User "%s" created%s.', $username, $input->getOption('admin') ? ' with ROLE_ADMIN' : ''));
+        $io->success(sprintf(
+            'Utilisateur "%s" cree, rattache au role systeme "%s"%s.',
+            $username,
+            $roleCode,
+            $isAdmin ? ' (bypass is_admin actif)' : '',
+        ));
 
         return Command::SUCCESS;
     }
diff --git a/src/Module/Core/Infrastructure/DataFixtures/AppFixtures.php b/src/Module/Core/Infrastructure/DataFixtures/AppFixtures.php
index 0ba45fa..bde7cc8 100644
--- a/src/Module/Core/Infrastructure/DataFixtures/AppFixtures.php
+++ b/src/Module/Core/Infrastructure/DataFixtures/AppFixtures.php
@@ -4,36 +4,72 @@ declare(strict_types=1);
 
 namespace App\Module\Core\Infrastructure\DataFixtures;
 
+use App\Module\Core\Domain\Entity\Role;
 use App\Module\Core\Domain\Entity\User;
+use App\Module\Core\Domain\Repository\RoleRepositoryInterface;
+use App\Module\Core\Domain\Security\SystemRoles;
 use Doctrine\Bundle\FixturesBundle\Fixture;
 use Doctrine\Persistence\ObjectManager;
 use Symfony\Component\PasswordHasher\Hasher\UserPasswordHasherInterface;
 
+/**
+ * Fixtures de base du module Core : 3 utilisateurs (1 admin + 2 standards)
+ * rattaches aux roles systeme RBAC seedes par la migration Version20260414150034.
+ *
+ * Note : le purger Doctrine execute avant load() supprime l'ensemble des
+ * entites managees, ce qui inclut la table role. On re-seede donc les roles
+ * systeme de maniere idempotente avant de rattacher les utilisateurs, afin
+ * que le workflow "make db-reset && make fixtures" reste one-shot.
+ */
 class AppFixtures extends Fixture
 {
     public function __construct(
         private readonly UserPasswordHasherInterface $passwordHasher,
+        private readonly RoleRepositoryInterface $roleRepository,
     ) {}
 
     public function load(ObjectManager $manager): void
     {
-        // TODO Task 6 : cette fixture sera refactoree pour attacher les entites Role RBAC.
+        $adminRole = $this->ensureSystemRole($manager, SystemRoles::ADMIN_CODE, 'Administrateur');
+        $userRole  = $this->ensureSystemRole($manager, SystemRoles::USER_CODE, 'Utilisateur');
+
         $admin = new User();
         $admin->setUsername('admin');
         $admin->setIsAdmin(true);
         $admin->setPassword($this->passwordHasher->hashPassword($admin, 'admin'));
+        $admin->addRbacRole($adminRole);
         $manager->persist($admin);
 
         $alice = new User();
         $alice->setUsername('alice');
         $alice->setPassword($this->passwordHasher->hashPassword($alice, 'alice'));
+        $alice->addRbacRole($userRole);
         $manager->persist($alice);
 
         $bob = new User();
         $bob->setUsername('bob');
         $bob->setPassword($this->passwordHasher->hashPassword($bob, 'bob'));
+        $bob->addRbacRole($userRole);
         $manager->persist($bob);
 
         $manager->flush();
     }
+
+    /**
+     * Retourne le role systeme correspondant au code donne, en le creant
+     * s'il n'existe pas encore (le purger Doctrine a pu vider la table role).
+     */
+    private function ensureSystemRole(ObjectManager $manager, string $code, string $label): Role
+    {
+        $role = $this->roleRepository->findByCode($code);
+
+        if (null !== $role) {
+            return $role;
+        }
+
+        $role = new Role($code, $label, isSystem: true);
+        $manager->persist($role);
+
+        return $role;
+    }
 }