I’ve wasted too much time (twice) updating the default calendar in Omarchy to use Monday as the first day of the week.

Turns out you can just click the “W” in the calendar view.

That updates a setting in ~/.config/omarchy/shell.json:

{
  "id": "omarchy.clock",
  "weekStartDay": "monday"
}
The calendar displays the month of October 2026, highlighting the 16th as a Friday and showing the week number 42 on the left side.