text: const fs = require('fs-extra')
  const _ = require('lodash')
  const parse5 = require('parse5')
  
  const tagsToMerge = ['html', 'head', 'body']
  
  function merge(toNode, fromNode) {
      if(toNode.childNodes && fromNode.childNodes) {
          const existingNodes = _.keyBy(toNode.childNodes, n => n.nodeName)
          fromNode.childNodes.forEach(fromChild => {
              const existingNode = existingNodes[fromChild.nodeName]
              if(existingNode && tagsToMerge.includes(fromChild.nodeName)) {
                  merge(existingNode, fromChild)
              } else {
                  toNode.childNodes.push(fromChild)
              }
          })
      }
      return toNode
  }
  
  module.exports = fs
      .readFile(require.resolve('./dev.html'), {encoding: 'utf-8'})
      .then(parse5.parse)
      .then(refDoc => doc => merge(doc, refDoc))
      .then(transform => require('./parse')(transform))
  