gistfile1.txt

 nixpkgs.overlays = [ ( self: super: {
      matomo = super.matomo.overrideDerivation (attrs: {
        src2 = super.fetchurl {
          url = "http://geolite.maxmind.com/download/geoip/database/GeoLiteCity.dat.gz";
          sha256 = "1kf4brki4v5kl7cxn4i8fifdw2bd004r4y62nb6ingay3592xnwh";
        };
        postUnpack = ''
          fileName=''${src2##*/}
          fileName=''${fileName#*-}
          fileName=''${fileName%.gz}
          gzip -c -d $src2 > ''${sourceRoot}/misc/''${fileName}
        '';
      });
    }
  )];