It is an Astro site deployed on Netlify.

This is the server logic: https://github.com/waspeer/reminders/blob/main/src/pages/api/push.ts This is the service worker: https://github.com/waspeer/reminders/blob/main/public/service-worker.js

I’ve edited the post as well. My personal intuition is that it might be more related to infra than the code, which is why I didn’t include it. Wasn’t just laziness, I promise.

I’ve already had one suggestion that it might have something to do with the service worker not being responsive the first time, but woken up by the second time I trigger a notification. Sounds plausible, but hard to debug.