diff --git a/derivations/decker/default.nix b/derivations/decker/default.nix
index 7ba6bb6c..52e73598 100644
--- a/derivations/decker/default.nix
+++ b/derivations/decker/default.nix
@@ -7,7 +7,7 @@
   zlib,
   bzip2,
   ncurses,
-  gmp
+  gmp,
 }: let
   resources = fetchFromGitHub {
     owner = "decker-edu";