diff --git a/pkgs/stdenv/generic/make-derivation.nix b/pkgs/stdenv/generic/make-derivation.nix
index eaa2ca0d6afc..54282e05df77 100644
--- a/pkgs/stdenv/generic/make-derivation.nix
+++ b/pkgs/stdenv/generic/make-derivation.nix
@@ -866,7 +866,8 @@ let
       );
 
     let
-      env' = if meta ? mainProgram then env // { NIX_MAIN_PROGRAM = meta.mainProgram; } else env;
+      env' =
+        if attrs ? meta.mainProgram then env // { NIX_MAIN_PROGRAM = attrs.meta.mainProgram; } else env;
 
       derivationArg = makeDerivationArgument (
         removeAttrs attrs [