I built my own nostr notifications solution... Although its not a NIP or a protocol. its just a simple Bun server that is designed to run on your server (Umbrel) and uses ntfy.sh to send the notifications.

GitHub

GitHub - hzrd149/nostr-secretary: Stupid simple nostr notifications

Stupid simple nostr notifications. Contribute to hzrd149/nostr-secretary development by creating an account on GitHub.

It still needs more work but its installable on your Umbrel if you add my app store

GitHub

GitHub - hzrd149/umbrel-community-app-store: My Umbrel Community App Store for noStrudel

My Umbrel Community App Store for noStrudel. Contribute to hzrd149/umbrel-community-app-store development by creating an account on GitHub.