diff --git a/pkgs/development/ruby-modules/bundled-common/default.nix b/pkgs/development/ruby-modules/bundled-common/default.nix
index 0fb92ea07928..75acf01e5df3 100644
--- a/pkgs/development/ruby-modules/bundled-common/default.nix
+++ b/pkgs/development/ruby-modules/bundled-common/default.nix
@@ -243,7 +243,7 @@ let
 
   basicEnv =
     if copyGemFiles then
-      runCommand name' basicEnvArgs ''
+      runCommand name' (basicEnvArgs // { __structuredAttrs = true; }) ''
         mkdir -p $out
         for i in $paths; do
           ${buildPackages.rsync}/bin/rsync -a $i/lib $out/