Can probably add another falsehood: that timezone information (in particular DST & UTC offsets) will never change. In reality, timezones are very much political

Can probably add another falsehood: that timezone information (in particular DST & UTC offsets) will never change. In reality, timezones are very much political and can change at any time with sometimes very little notice. Last major change US folks may remember occurred around 2007, when daylight saving time was expanded by 6 weeks. I know of clocks that are still wrong from that change. At a previous job, I spent over a year working on a library for timezones built on top of Boost. The handling of historical timezones was a particular pain in the ass.