Ghost/core/server/overrides.js

const moment = require('moment-timezone');

/**
 * force UTC
 *   - you can require moment or moment-timezone, both is configured to UTC
 *   - you are allowed to use new Date() to instantiate datetime values for models, because they are transformed into UTC in the model layer
 *   - be careful when not working with models, every value from the native JS Date is local TZ
 *   - be careful when you work with date operations, therefor always wrap a date into moment
 */
moment.tz.setDefault('UTC');

/**
 * https://github.com/TryGhost/Ghost/issues/9064
 */
global.Promise = require('bluebird');