The official docs have you set it up so the foo.socket can start your foo.service automatically when nginx sends something to the socket file, but don't you want your foo.service running all the time anyway? I'm already paying for the server, so it's not like it would get cheaper if my foo.service was stopped to save resources or whatever. It seems overly complicated for no good reason, and it makes it more complicated to switch between other wsgi/asgi servers (no other wsgi/asgi server works like this), so I removed the foo.socket part last night. Convince me I'm wrong.