I recently started using Fly to host the anycast DNS name servers for my DNS hosting service SlickDNS (https://www.slickdns.com/ https://www.slickdns.com/). Th

I recently started using Fly to host the anycast DNS name servers for my DNS hosting service SlickDNS (https://www.slickdns.com/ https://www.slickdns.com/). There were some initial teething issues as Fly only recently added UDP support, but they were very responsive to the various bugs I reported and fixed them. My name servers have been running problem free for several weeks now. The Fly UX via the flyctl command-line app is excellent, very Heroku-like. For apps that need anycast the only real alternative to Fly that I found is AWS Global Accelerator, but it limits you to two anycast IP addresses, it's much more expensive than Fly and you're fighting the AWS API the whole time.