けんき says to YSITDBecause require-dir use fs, so EMFILE occured. You can go to node_modules/require-dir/index.js , Line:4 modify it into var FileQueue = require('filequeue'); var fs = new FileQueue(100); then, i think it will work (You may send pull request to requireDir's repository if it works well)at Sun, May 22, 2016 8:05 PM