anchor.diff:  
       runHook renameImports
   
  +    PIDS=()
       if [ -n "$subPackages" ] ; then
           for p in $subPackages ; do
  -            go install $buildFlags "''${buildFlagsArray[@]}" -p $NIX_BUILD_CORES -v $goPackagePath/$p
  +            go install $buildFlags "''${buildFlagsArray[@]}" -p $NIX_BUILD_CORES -v $goPackagePath/$p &
  +            PIDS+=("$!")
           done
       else
  -        (cd go/src
  -        find $goPackagePath -type f -name \*.go -exec dirname {} \; | sort | uniq | while read d; do
  +        pushd go/src
  +        while read d; do
  +          {
               echo "$d" | grep -q "/_" && continue
               [ -n "$excludedPackages" ] && echo "$d" | grep -q "$excludedPackages" && continue
               local OUT
  
positive.code:             if [ -n "$OUT" ]; then
                echo "$OUT" >&2
              fi
          done)
      fi
  
      runHook postBuild
    '';
  
negative.code:   checkPhase = args.checkPhase or ''
      runHook preCheck
  
      PIDS=()
      if [ -n "$subPackages" ] ; then
          for p in $subPackages ; do
              go test -p $NIX_BUILD_CORES -v $goPackagePath/$p &
          done
          PIDS+=("$!")
      else
          pushd go/src
          while read d; do
              go test -p $NIX_BUILD_CORES -v $d
          done < <(find $goPackagePath -type f -name \*_test.go -exec dirname {} \; | sort | uniq)
          popd
          PIDS+=("$!")
      fi
  
      # Exit on error from the parallel process
      for PID in "''${PIDS[@]}"; do
          wait $PID || exit 1
      done
  
      runHook postCheck
    '';
  