diff --git a/src/Dto/UserTokenLoginDto.php b/src/Dto/UserTokenLoginDto.php
index 2c621a3..5befd58 100644
--- a/src/Dto/UserTokenLoginDto.php
+++ b/src/Dto/UserTokenLoginDto.php
@@ -13,23 +13,20 @@ use Symfony\Component\Validator\Constraints as Assert;
 final class UserTokenLoginDto
 {
     /**
-     * The username of the User to be authenticated.
+     * The identifier (email, username) of the User to be authenticated.
      */
     #[Assert\NotBlank()]
-    #[Assert\Length(min: 4, max: 30)]
-    #[Assert\Regex('/^[a-z0-9_-]+$/')]
-    public readonly string $username;
+    public readonly string $identifier;
 
     /**
      * The password of the User to be authenticated.
      */
     #[Assert\NotBlank()]
-    #[Assert\Length(min: 12)]
     public readonly string $password;
 
-    public function __construct(string $username, string $password)
+    public function __construct(string $identifier, string $password)
     {
-        $this->username = $username;
+        $this->identifier = $identifier;
         $this->password = $password;
     }
 }
diff --git a/src/Repository/UserRepository.php b/src/Repository/UserRepository.php
index 9bc97fa..67b3fee 100644
--- a/src/Repository/UserRepository.php
+++ b/src/Repository/UserRepository.php
@@ -41,6 +41,21 @@ class UserRepository extends ServiceEntityRepository implements PasswordUpgrader
         $this->getEntityManager()->flush();
     }
 
+    /**
+     * Find an User by any of it's unique properties
+     * @param string $identifier An id, email or username
+     */
+    public function findOneByIdentifier(string $identifier): ?User
+    {
+        return $this->createQueryBuilder('u')
+            ->andWhere('u.id = :val')
+            ->orWhere('u.email = :val')
+            ->orWhere('u.username = :val')
+            ->setParameter('val', $identifier)
+            ->getQuery()
+            ->getOneOrNullResult();
+    }
+
     public function findOneByAccounting(Accounting $accounting): ?User
     {
         return $this->createQueryBuilder('u')