go-modules: Fix the application of reference removal on packages like mongo-tools

pkgs/development/go-modules/generic/default.nix

@@ -1,6 +1,9 @@
 { go, govers, lib }:
 
-{ name, buildInputs ? [], nativeBuildInputs ? [], passthru ? {}
+{ name, buildInputs ? [], nativeBuildInputs ? [], passthru ? {}, preFixup ? ""
+
+# We want parallel builds by default
+, enableParallelBuilding ? true
 
 # Disabled flag
 , disabled ? false
@@ -156,13 +159,16 @@ go.stdenv.mkDerivation (
 
     dir="$NIX_BUILD_TOP/go/bin"
     [ -e "$dir" ] && cp -r $dir $out
+
+    runHook postInstall
+  '';
+
+  preFixup = preFixup + ''
     while read file; do
       cat $file ${removeExpr removeReferences} > $file.tmp
       mv $file.tmp $file
       chmod +x $file
     done < <(find $out/bin -type f 2>/dev/null)
-
-    runHook postInstall
   '';
 
   disallowedReferences = lib.optional (!allowGoReference) go
@@ -170,6 +176,8 @@ go.stdenv.mkDerivation (
 
   passthru = passthru // lib.optionalAttrs (goPackageAliases != []) { inherit goPackageAliases; };
 
+  enableParallelBuilding = enableParallelBuilding;
+
   meta = {
     # Add default meta information
     platforms = lib.platforms.all;