One approach is to store everything in UTC, and display in the timezone of the user.
Dealing with timezones - including DST - properly is a must-have, no way around it. I live in a country that uses DST, a lot of Europe does that. If my calendar would be off by 1 hour half of the year, I'd consider it broken and seriously doubt the competence of its authors. This is the core domain of a calendar app! It would be like an email app that just silently drops every other email.
I'd love for us to ditch DST by the way, hate it every time. Its bad for the economy, its bad for our health, its bad for software.
I don't trust UTC for future dates, only for things that have already happened. Future dates are tentative in that their UTC representation can change. For example, if I converted a Kazakh user's event slated for April 1, 2024 to UTC before February 1, 2024, the event time would be off by one hour.
Dealing with timezones - including DST - properly is a must-have, no way around it. I live in a country that uses DST, a lot of Europe does that. If my calendar would be off by 1 hour half of the year, I'd consider it broken and seriously doubt the competence of its authors. This is the core domain of a calendar app! It would be like an email app that just silently drops every other email.
I'd love for us to ditch DST by the way, hate it every time. Its bad for the economy, its bad for our health, its bad for software.