Tag: Time Zones

What if event organizers could share a link that would do the work for you? If someone clicked on mytime.at/5pm/EST, they would see their local version of that time. It sounded simple enough.

I began coding.

I knew trying to manage time is a fool’s errand, but that’s what datetime libraries are for. I would merely build an extra time zone conversion layer on top.

Surely that couldn’t be complicated

…Right?

I soon discovered just how wrong I was. One after another, I kept learning the falsehood of yet another “fact” that had seemed obviously true. Eventually my original vision became literally impossible to pull off without making serious compromises.

Zain Rizvi

Falsehoods programmers believe about time zones (Zain Rizvi)

What’s wrong with calculating the exact UTC time the event is starting and storing only that?

The problem is that we are losing crucial details about the event creator’s original intent.

…

My strong recommendation here is that the most important thing to record is the original user’s intent. If they said the event is happening at 6pm, store that! Make sure that when they go to edit their event later they see the same editable time that they entered when they first created it.

Simon Willison

Storing times for human events (Simon Willison’s Weblog)