code: function ReadableStream(options, cursor) {
    if (cursor) this._cursor = cursor;
    this._pending = 0; // How many time we called _read while no cursor was available
    this._index = 0;
    this._maxRecursion = 1000; // Hardcoded
    this._highWaterMark = options.highWaterMark;
    this._closed = false;
  
    Readable.call(this, {
      objectMode: true,
      highWaterMark: this._highWaterMark
    });
  }
docs: Experimental, but should work fine.