Currently running within my home systems is a Zabbix instance for network monitoring/alerting and a Unifi Protect camera system. Zabbix will happily send emails when an event occurs as will Unifi protect. The problem is email is based on server checks for the most part. For Zabbix this is not supper bad, but for the video system it is terrible when a doorbell ring event comes several minutes after the fact.
After some digging it turns out Unifi uses the built in Google services for push notifications. As my phone has no Play Services, I am unable to receive push notifications from Unify. Luckily, Unifi Protect (or Unifi in general) does support using web hooks for events.
Two fairly common candidates turn up for self hosted push notifications, gotify and ntfy. Both seem very capable, are self host-able and offer a direct Android client available on FDroid. The deciding factor for my use case was gotify does not allow you to have a common group type subject while ntfy does. This is fairly critical for my use case as I want my NMS and video system sending to a single group/topic/subject and that notification going to one or more users.
The setup works extremely well. I typically get the push notification in under a second from the doorbell being pressed. Unifi Protect allows attaching an image however it is base64 encoded and I have yet to figure that part out (so I can get a snapshot from the camera with the notification).
Plugging in Zabbix was crazy simple as well thanks to Paul Sørensen @ https://paulsorensen.io/configure-ntfy-notifications-zabbix/. The integration is nothing short of amazing.
Details on ntfy setup with Unifi Protect coming soon.