For context, cjdns appears to be a routing suite for implementing a darknet overlay over the normal internet. I'm not entirely sure what Cloudflare is perceived to stand for, but it is a strongly centralized service and cjdns appears to be going for decentralization. (But I'd imagine a Cloudflare-like service, including centralized management = economies of scale in sysadminning, would still be valuable in a cjdns darknet.)

See https://github.com/cjdelisle/cjdns , https://hyperboria.net/ , and https://www.reddit.com/r/darknetplan/

cjdns is a different thing from cdnjs