diff --git a/lib/fudo/auth/kerberos/kdc.nix b/lib/fudo/auth/kerberos/kdc.nix
index 95b49c0..f41d51c 100644
--- a/lib/fudo/auth/kerberos/kdc.nix
+++ b/lib/fudo/auth/kerberos/kdc.nix
@@ -323,7 +323,7 @@ let
                 ProtectKernelLogs = true;
                 MemoryDenyWriteExecute = true;
                 RestrictRealtime = true;
-                LimitNOFILE = 4096;
+                LimitNOFILE = "4096";
                 User = cfg.user;
                 Group = cfg.group;
                 # Server will retry -- this results in stacking