A way to check all the stuff in the background

[aprilito1965]

Issue title

It is actually not an issue, just suggestion of functionality expansion

Issue Description

is there a way to make all the math and checks in the background without delay of user connection?
For example connecting to some backend services from frontend to minimize noticeable connection delay for user. And inf the check fails after connection - add this ip to blacklist (and maybe drop connection)

I am still exploring your beautiful work with that script and nginx capabilities.
Thank you!