When protecting a set of small static websites against the onslaught of AI crawler bots, something like Anubis is a lot of effort to install.
So, I knocked up something that might help against the dumber bots, coded entirely inside nginx config so there's no other moving parts to install.
I've done some isolated testing but haven't installed it in anger yet - but I might add it to e.g. my blog and #Faircamp sites.
https://evilgeniusrobot.uk/posts/a-simple-bot-gatekeeper-for-nginx.html