Nope, your uptime kuma speaks to it directly, and it basically acts as a signal client for you.

https://github.com/bbernhard/signal-cli-rest-api

Its very finicky to setup, but once you get it working its pretty good. Sometimes needs to be reauthenticated though.

Kuma notification settings:

Is lateral movement really a risk for you? Most internet malware is fully automated drive-by stuff. They hit you, gain execution and your part of their botnet. They don’t need to move laterally, because they have all the execution they need.

Moving laterally requires a human (or agent these days), which has a non-zero time and resource cost, so the only reason anyone is going to do that to you is if you are a very valuable target.

Do whatever you like for learning/fun, but I wouldn’t stress to much. Your risk level is probably very low.

Uptime Kuma, only really care if it’s up or not. Got about 30 services monitored, sending notifications to Signal.