The only 2 ddns clients i found that are supported are
ddclient which seems to DOA since the maintainer seems to not want to support it anymore
https://sourceforge.net/p/ddclient/wiki/Home/
or
duckdns
neither have support for cloudflare
i found this one
https://github.com/oznu/docker-cloudflare-ddns and im going to try it out but i just thought you guys should know i cant find cloudflare support as a ddns client
ddclient is definitely actively maintained…
last commit was today to add the new cloudflare token restrictions
* Added support for cloudflare API tokens. Do not provide a login if using one. The token must have permissions for All zones - Zone:Read, DNS:Edit.
your link is just a long-dead project, the link in our container is the current fork and what our container is based on.
You are absolutely correct i was wrong and figured it out
once you run your docker you have to edit the file /config/ddclient.conf
find the hosting provider you are using and uncomment it
i also had to add
use=web at the top
use=web
protocol=cloudflare,
zone=domain.tld,
ttl=1,
login=EMAIL,
password=GLOBALAPIKEY
domain.tld,my.domain.tld
good to go then? if you need any help, just pop into our discord. we’re not quite so active right now (it’s late (or early for half the team)) but we have fun discussions and offer fairly quick assistance 
as another note, while using the globalapikey works, as the git commit notes i posted show, there is a more restrictive way you can create your key (rather than using the global) to still provide full functionality. Something to consider if you’re security conscious.
The token must have permissions for All zones - Zone:Read, DNS:Edit
I’m not sure if we moved to build from the GitHub repo. It was the plan but might have forgotten it.