diff --git a/services/python-ci.nix b/services/python-ci.nix
index 2523d8f65..5a6a4c43a 100644
--- a/services/python-ci.nix
+++ b/services/python-ci.nix
@@ -12,6 +12,14 @@ in
 
   config = mkIf cfg.enable {
 
+    users.users = {
+      python-ci = {
+        isSystemUser = true;
+        group = "nogroup";
+        description = "Python CI user";
+      };
+    };
+
     systemd.services.python-ci = {
       description = "CI Nix en Python";
       requires = ["network-online.target"];
@@ -19,7 +27,7 @@ in
       environment = { HOME = "/var/lib/python-ci"; NIX_PATH = concatStringsSep ":" config.nix.nixPath; NIXPKGS_ALLOW_UNFREE = "1";};
       path = with pkgs;[ nix gnutar gzip ];
       serviceConfig = {
-        DynamicUser = true;
+        User = "python-ci";
         StateDirectory = "python-ci";
         RuntimeDirectory = "python-ci";
         RuntimeDirectoryPreserve = "yes";