diff --git a/flake.nix b/flake.nix
index 47b352e..5ecab04 100644
--- a/flake.nix
+++ b/flake.nix
@@ -120,7 +120,7 @@
         systemd.services.dsa41generator = {
           wantedBy = ["multi-user.target"];
           after = ["network.target"];
-          serviceConfig.ExecStart = ''${webdocs}/bin/server --address "${cfg.address}" --port ${cfg.port}'';
+          serviceConfig.ExecStart = ''${webdocs}/bin/server --address "${cfg.address}" --port ${toString cfg.port}'';
         };
       };
     };