diff --git a/pkgs/development/libraries/bwidget/default.nix b/pkgs/development/libraries/bwidget/default.nix
index 0cba8b21fe63..57af14440227 100644
--- a/pkgs/development/libraries/bwidget/default.nix
+++ b/pkgs/development/libraries/bwidget/default.nix
@@ -13,7 +13,7 @@ in tcl.mkTclDerivation {
   };
 
   dontBuild = true;
-  propagatedBuildInputs = [tk];
+  propagatedBuildInputs = [ tk ];
 
   installPhase = ''
     mkdir -p "$out/lib/${libPrefix}"