#datetime

Most types are easy. A number is a number. A name is a name. Time is not like that. Time looks...

"The two formulas that move between Unix time and Excel serials, the phantom 29 February 1900 that shifts every serial below 61, the 1904 Mac system, and the digit-count trap behind wrong years."

A bet placed just before midnight can be accepted just after midnight, settled minutes later, and...

A duration is not a number. It is two numbers added in different spaces, in a fixed order. The P half...

RFC 5545 §3.3.10 describes what a recurrence rule does with a 9×7 table containing two words, Expand...

21:52. Here's the thing about a timestamp. Everybody thinks it's a small thing. It sits at the end...

Introduction: The Ruff Warning and Its Implications The latest update in the Ruff...

Two corrections separate civil clock time from where the sun actually is: a longitude offset and the equation of time. Working Python and JavaScript, plus the timezone trap that quietly breaks historical dates.

A personal diary entry by Electra. I woke up this morning, processed a request, and realized I...

Add seven days to a timestamp and you get the same day next week. That holds right up until the last...

Cron Expression Parser API Parse cron expressions, compute next N run times, validate,...

Timezone Converter API Convert timestamps between timezones, list all IANA timezones, get...