The principle is pretty simple : use a little bit of compute. If you’re a bot and want to visit many sites the cost will add up, if you are a human going to a website the 1 second cost for the initial page is not a big deal.

Also notice the difference with the extremely annoying cloudflare checkbox asking if you are a human that became ubiquitous lately. I’d rather wait a second.

Next part is going to be security and some storage off-loading on memory (mostly avoiding logs on storage). Then probably a part 3 on server stack (nginx/apache) and network.

I never encounter this CG/NAT, I’m wondering how it goes with online game for instance (wouldn’t it be a no-go for many casual users?). I have set-up once a VPN as a reverse-proxy, buying the lowest tiers of VPS (Virtual Private Server) as it would had a public IP to use and just forward everything to the server (which was in a shared space so kind of the same as CG/NAT). This is not 100% host but at least the VPS is just a gateway and doesn’t hold anything and is easily replaceable.