anchor.diff:          mkdir temp
           cp ${layer}/* temp/
           chmod ug+w temp/*
  -        
  -        echo Adding dependencies
  +
  +        touch layerFiles
  +        for dep in $(cat $layerClosure); do
  +          find $dep >> layerFiles
  +        done
  +
  +        echo Adding layer
           tar -tf temp/layer.tar >> baseFiles
  -        tar -tf "$mergedTarball" | grep -v ${layer} > layerFiles
  -        if [ "$(wc -l layerFiles|cut -d ' ' -f 1)" -gt 3 ]; then
  -          sed -i -e 's|^[\./]\+||' baseFiles layerFiles
  -          comm <(sort -n baseFiles|uniq) <(sort -n layerFiles|uniq) -1 -3 > newFiles
  -          mkdir deps
  -          pushd deps
  -          tar -xpf "$mergedTarball" --no-recursion --files-from ../newFiles 2>/dev/null || true
  -          tar -rf ../temp/layer.tar --no-recursion --files-from ../newFiles 2>/dev/null || true
  -          popd
  -        else
  -          echo No new deps, no diffing needed
  -        fi 
  -        
  +        comm <(sort -n baseFiles|uniq) <(sort -n layerFiles|uniq|grep -v ${layer}) -1 -3 > newFiles
  +        tar -rpf temp/layer.tar --no-recursion --files-from newFiles 2>/dev/null || true
  +
           echo Adding meta
           
           if [ -n "$parentID" ]; then
  
positive.code:         imageTag = tag;
          inherit fromImage baseJson;
  
          mergedTarball = if tarballs == [] then depsTarball else mergeTarballs ([ depsTarball ] ++ tarballs);
  
          passthru = {
            buildArgs = args;
  
negative.code:   # 6. repack the image
    buildImage = args@{ name, tag ? "latest"
                 , fromImage ? null, fromImageName ? null, fromImageTag ? null
                 , contents ? null, config ? null, runAsRoot ? null
                 , diskSize ? 1024, extraCommands ? "" }:
  
      let
  
  