{ stdenv }: datasets: with stdenv.lib; stdenv.mkDerivation { name = "merged-dataset"; preferLocalBuild = true; phases = [ "installPhase" ]; inherit datasets; installPhase = '' mkdir -p $out n=1 for d in $datasets; do ln -s $d $out/$n let n=n+1 cat $d/dataset >> $out/dataset done ''; }