I tried both MQTT and just the plain HTTP variant, and I couldn’t get either to work. I’ve fully settled on the latter you mentioned, Traccar. it’s pretty much what I’ve wanted: self-hosted, easy to set up, beautiful web interface. Thanks for the suggestions!
not even a vegetarian/vegan, and this is not a bad idea at all. a lot more people than I thought need to learn to love their veggies, nuts, beans, etc