diff --git a/pkgs/build-support/go/module.nix b/pkgs/build-support/go/module.nix
index d0fd8928c91ab8..2fb59c63482905 100644
--- a/pkgs/build-support/go/module.nix
+++ b/pkgs/build-support/go/module.nix
@@ -289,7 +289,8 @@ let
 
     disallowedReferences = lib.optional (!allowGoReference) go;
 
-    passthru = passthru // { inherit go goModules vendorHash; } // { inherit (args') vendorSha256; };
+    passthru = passthru // { inherit go goModules vendorHash; }
+                        // lib.optionalAttrs (args' ? vendorSha256 ) { inherit (args') vendorSha256; };
 
     meta = {
       # Add default meta information