How to actually use this in a systemd setup?

The example in the repo shows how to gracefully restart a standalone executable. In the case of systemd managed services, how can one make the spawned child process to be managed by systemd? The child process creation is encapsulated in the library(the `Command::spawn` call) and as far as I know this kind of child processes are not directly managed by systemd, meaning when the parent process eventually exits, the systemd will think the service is down and try to restart it, disregarding the child process.

Not a Linux expert myself but I do want to use this in my Rust project. Any help is greatly appreciated.