docs: function send(out, headers) {
            // Check for headers
            if (!headers) {
              headers = {};
            }
            // Check out value
            if (!out) {
              return next();
            }
            // Do cache things if necessary
            if (options.cache) {
              var expire = new Date();
              expire.setYear(expire.getFullYear() + 1);
              headers['Expires'] = options.expires || expire.toUTCString();
              headers['Cache-Control'] = 'public, max-age=' + (options.maxage || 31536000/*One year in seconds*/);
              headers['Last-Modified'] = stat.mtime.toUTCString();
              cache[path] = {out: out, headers: headers};
            }
            // Write out transformed value
            writeOut(200, res, out, headers, options);
          }