How do you communicate to outside of docker container?

I have installed Kopia using the Docker method. Now I’m trying to send a notification on task complete but I can’t figure out a way to talk to outside of Kopia container.

Since there is no curl included in the docker image, I can’t just curl another URL.

What other options do I have? How do rest of you that are running Kopia in container communicate to outside of container?

Or do you just trust Kopia to not have issues and manually check if backup was successful?