[xyzzy_plugh]

I cannot overstate how bad this advice is. Everything should be UTC by default. You can explicitly use timestamp with timezones and frankly it's trivial to query something like midnight-to-midnight PST. Your team should learn this as early as possible.

Build tooling around this, warn users, hell, educate them, but don't set up foot-guns like non-UTC.

If I see a timestamp without a timezone, it must always be UTC. To do anything else is to introduce insanity.

[higeorge13]

This. I once joined a company with local timezone per deployment and it was a nightmare. Not only in terms of development and debugging, but even for all the support tools required and the numerous bugs we found.

I insisted that all the tools that were going to be installed under my watch would be UTC, and never experienced any time issue on them.