Debian 13, Postgres, and the US/* time zones

The timezone names are defined by the Olson database, not Debian. It is the only sensible system in our ecosystem. It certainly beats Outlook which still wrongly insists that my timezone is GMT just because I live in the UK and still confuses everyone (it isn't during the summer; we use BST over the summer, not GMT).

Any moderately reasonable system would be backwards compatible and/or migrate existing values

> The worst part about this is that it didn't get so much as a mention in the Debian 13 release notes. I read through that document before going for it and never encountered it. Indeed, even now, you won't find "tzdata" or "zone" in it.

It's been backwards compatible for 30 years, you've had plenty of time to migrate

Did it give any noticeable deprecation warning? If a piece of functionality is deprecated but users can't notice, is it really deprecated?

How and where, in principle, do you suppose it should (be able to) do so, given the functionality? It's just localizing timestamps, and the result might bubble through multiple layers of software before being presented to anyone. It's not as if C APIs get designed up front to return structures with a boolean "btw you called this in a nonstandard way that might fuck up in the future" flag (or, say, a pointer to a deprecation-warning structure; and then that interface has to be rock-solid stable to be of use) for every call. And if they did, nobody would ever write code that checks it.