Start a server and restart it any time there is a change in a file

start.js

'use strict'
const path = require('path')
const cp = require('child_process')
const gaze = require('gaze')
// edit to match the path of your server
const serverPath = __dirname+'/index'

let server;
let serverScript = 'require(\''+serverPath+'\')'

function runServer(cb) {
  if (server) {
    server.kill('SIGTERM')
  }
  server = cp.spawn('node', ['--eval', serverScript], {
    env: Object.assign({ NODE_ENV: 'dev' }, process.env),
    stdio: 'inherit',
    silent: false,
  })
}

process.on('exit', () => {
  if (server) {
    server.kill('SIGTERM')
  }
})
runServer()
gaze(['**','!node_modules/**'], function(err, watcher) {
  this.on('all', function(event, filepath) {
    runServer()
  })
})