Progressive Ember - Moment Timezones

A walk through the real effort to transition an enterprise level Ember application to a progressive web application.

Part three: Moment Timezones

This will be quick

In my latest build, we still see some 12 kB for moment.js and a whopping 43 kB for tz.min.js (moment timezones).

No Lodash - Build

What on earth could 43 kB of JavaScript related to timezones possibly be?

Everything, ever.

The answer is apparently all timezone data, forever. Browsing through the ember-cli-moment-shim repository led me to this part of the documentation.

I’m not sure if this was auto-generated at some point, or I was just copy/paste happy from the documentation, but apparently I was bundling all timezone data throughout time. I’m surprised that’s even a thing; how many applications need that?

My application doesn’t need anything specific to timezones, so a simple switch of my config from:

moment: {
    includeTimezone: 'all'


moment: {
    includeTimezone: 'none'

drops some significant kilobytes. I feel ridiculous for missing that initially, but I’ll take the easy win.



No Lodash - Build


No moment timezones - Build

Up next, I’ll see if I can replace ember-cli-showdown to save another 23 kB.

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