How to keep syncthing from running when on metered network?

I'd like to use Syncthing on my Macbook, but since MacOS doesn't have a concept of "metered networks" (seriously Apple, how many decades do you need to add this???), I need to come up with a way to stop Syncthing from running when I'm connected to my phone's shared hotspot connection. I'm thinking about just writing a small script that will kill Syncthing when it's connected to any of the SSIDs that I specify (which I'd probably just store in a text file), and then re-start when it's connected to any other network.