Framework SDKs
Middleware that looks up the visitor behind every request your web app serves.
The middleware looks up the visitor on every request, so your own handlers get the answer without calling anything: where they are, which network they come from, and whether it's a VPN, a proxy, Tor or a hosting server. Nothing is refused until you give it a condition to refuse on, a country, a network type or anything else in the answer.
Each one is built on the programming SDK for its language.