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Comment by netsharc | Hacker News Reader

> This stuff moves a lot, too: the tz database (also known as the Olson database), which is the listing of timezone rules we use as programmers to calm this chaos, gets updated many times a year.

Without looking it up, I would say the last change happened when North Korea decided to sync its timezone with South Korea... or have they reverted that since Trump cancelled their summit?

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I think it's one of the more recent changes.

It's actually pretty cool- all of this is discussed on the tz mailing list, so you can see how it all works yourself! https://mm.icann.org/pipermail/tz/

Thanks that's a great link. Indeed as you said I'm learning quite a lot about how it works just from this thread which started about the Western Greenland timezone!

https://mm.icann.org/pipermail/tz/2017-December/025606.html

Checking 2018e, that is in fact the last change to the database, though they also updated some past timestamps:

> From 1994 through 2017 Namibia observed DST in winter, not summer.

> In 1946/7 Czechoslovakia also observed negative DST in winter.

2018d had a change to palestine's DST date (a week earlier than usual), Casey Station moving from +11 to +08 and a few other historical changes/fixes.

To clarify: Namibia had negative DST in (southern hemisphere) winter. They had UTC+1 in the winter (April to September) and UTC+2 in the summer. Now they're UTC+2 year-round, aligned with South Africa. The reason seems to be historical - if you're on year-round UTC+2, and you want to be on UTC+1 in winter/UTC+2 in summer, it's easier to say "we're setting the clocks back an hour in winter" than to say "we're setting the clocks back an hour year-round... and then forward an hour in summer."

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