This is an experiment with making gunicorn gracefully scale down to zero after X seconds, as a way to do application-level scale-to-zero behaviour in applications that use a webserver like Gunicorn. The idea here is that you do not need to mess too much internal logic of an existing application, nor put it in a container if you use this.
Instead you use the web server's own support for handling SIGTERM signals, to allow gracefully scaling down of processes when they are not in use.
If you're using Linux to run a server, the chances of Systemd being used to manage your processes is fairly high, as it's the default option for a number of linux distributions now.
It also means you might not need a complicated "serverless" system to orchestrate scaling up and down, to reclaim memory on a server for us in other tasks if you have a website or webservice that isn't continually serving traffic.