Caching
It would be great to have caching added somehow to reduce HTTP requests when bots spam servers.
DNS is cachable with a caching resolver, such as Unbound.
Install unbound on your server (available in most distros incl. Debian, Fedora, Arch, Ubuntu, etc.), enable&start the service and set ['127.0.0.1'] as the DNS server in options.
Besides putting a caching resolver in front, you could use a in-memory cache and expire it after a fixed amount of time:
https://github.com/medikoo/memoizee#expire-cache-after-given-period-of-time
I'm not totally opposed to having a ttl-based cache in the module, but it would have to be opt-in.
Could we re-open this for TTL-based cache in module?
Or perhaps just add to the README a link to https://github.com/medikoo/memoizee#expire-cache-after-given-period-of-time?