rocket.chat.mqtt/node_modules/npm/lib/install/action/global-link.js

It's a MQTT Server, using redis to scale horizontally.

'use strict'
var npm = require('../../npm.js')
var packageId = require('../../utils/package-id.js')

module.exports = function (staging, pkg, log, next) {
  log.silly('global-link', packageId(pkg))
  npm.link(pkg.package.name, next)
}