diff --git a/public/environment.nix b/public/environment.nix
index 15fd39b..38746bc 100644
--- a/public/environment.nix
+++ b/public/environment.nix
@@ -23,6 +23,9 @@ in
   # Lancement de dbus pour les utilisateurs
   services.dbus.socketActivated = true;
 
+  # NixOS Hardening
+  security.grsecurity.enable = true;
+
   # Paquets
   environment = {
     systemPackages = with pkgs; [
diff --git a/public/service-hydra-build.nix b/public/service-hydra-build.nix
index e997a30..98a6453 100644
--- a/public/service-hydra-build.nix
+++ b/public/service-hydra-build.nix
@@ -20,9 +20,10 @@ mkIf cfg.hydra-builder {
   nix.gc.automatic = true;
 
   users.users."hydrabld" = {
-    description = "Execution des job hydra";
+    description = "Execution des jobs hydra";
     group = "nixbld";
-    isNormalUser = false;
+    extraGroups = [ "nixbld" ];
+    isNormalUser = true;
 
     openssh.authorizedKeys.keys = [
       "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIGYpjcWJCf8dXpv2LmoIaNVbwZXEC50QUU6Az+lqeD89 hydra radx"