diff --git a/pkgs/applications/editors/emacs/build-support/melpa.nix b/pkgs/applications/editors/emacs/build-support/melpa.nix
index 4a22ea195a98..718a0c4d2c1c 100644
--- a/pkgs/applications/editors/emacs/build-support/melpa.nix
+++ b/pkgs/applications/editors/emacs/build-support/melpa.nix
@@ -66,7 +66,7 @@ libBuildHelper.extendMkDerivation' genericBuild (finalAttrs:
   */
 , recipe ? (writeText "${finalAttrs.pname}-recipe" ''
     (${finalAttrs.ename} :fetcher git :url ""
-              ${lib.optionalString (finalAttrs.files or null != null) ":files ${finalAttrs.files}"})
+              ${lib.optionalString (finalAttrs.files != null) ":files ${finalAttrs.files}"})
   '')
 , preUnpack ? ""
 , postUnpack ? ""
@@ -79,7 +79,7 @@ libBuildHelper.extendMkDerivation' genericBuild (finalAttrs:
   elpa2nix = args.elpa2nix or ./elpa2nix.el;
   melpa2nix = args.melpa2nix or ./melpa2nix.el;
 
-  inherit commit ename recipe;
+  inherit commit ename files recipe;
 
   packageBuild = args.packageBuild or packageBuild;