Shift Calendar & Alarm: A shift-worker's calendar that starts blank, not full

Hi Product Hunt, I'm a solo developer from Japan. I built Shift Calendar & Alarm because most calendar apps assume you work a normal Monday-to-Friday schedule - and if your days off move around every week, that assumption gets in the way more than it helps. So the whole app starts from nothing. You open it, and it's blank. You add your shifts, one at a time, and the calendar grows around your actual schedule instead of the other way around. A few things I put real work into: - Every shift can carry its own alarm, including cross-midnight shifts (22:00-06:00). Alarms ring even with the app fully closed. - Public holidays are calculated for 10 countries, in 10 languages, without any external data file. - Payday tracking and anniversaries live right on the same calendar, so you can see at a glance if a shift lands on a day it shouldn't. - No account, fully offline, and every bit of data - shifts, alarms, settings - stays only on your device. It's free, with a small banner ad. I'd love to hear from anyone with an irregular schedule - nurses, factory shift workers, retail, hospitality: what does your current calendar setup look like, and what's still missing from it?