Europe changed clocks on Sunday, the US does it next Sunday. Check your scheduled posts
Every year I tell myself I'll remember this before it happens. Every year somebody pings me on a Monday asking why the 9am posts went out at 8. Europe moved clocks back on October 25. The US does it on November 1. So for one week the gap between, say, Madrid and New York is 5 hours instead of the usual 6, and anything that quietly assumed a fixed offset is now wrong by an hour. If you run…
On October 25, Europe adjusts its clocks back, while the United States sets its clocks forward on November 1. For a week, the time difference between locations like Madrid and New York reduces by one hour, causing issues for scheduled tasks, social media posts, newsletters, and cron jobs. This disruption can occur due to a few reasons: storing time in offsets instead of IANA zone names, using server cron jobs in UTC when humans think in local time, treating the hour that occurs twice during the fall-back period without proper handling, and failing to display the audience's timezone alongside the scheduled time.
To avoid these problems, it is recommended to store IANA zone names, use server cron jobs with zone specifications, make jobs idempotent, handle the double or missing hour deliberately, and always display the recipient's timezone. Regularly auditing scheduled items and scheduling tests to freeze time around the clock change dates can also help prevent these issues.
Written by urgent.news from Dev.to's reporting — not their text. Machine-written — may contain errors; check the original before relying on it.
