docs: function bundleCompilers(compilers, opts) {
      if (!opts) { opts = {}; }
  
      var transforms = [].concat(opts.pipeTo || []);
      var s = stream.PassThrough({ objectMode: !!opts.objectMode });
  
      Rx.Node.writeToStream(
          compilers.flatMap(function (res) {
              var bundle = res.compiler.bundle(R.omit(["objectMode", "pipeTo"], opts));
  
              return Rx.Node.fromStream(
                  R.reduce(function (b, t) {
                      return b.pipe(t(res.name, res.compiler));
                  }, bundle, transforms)
              );
          }),
          s
      );
  
      return s;
  }