DanielTheGeek By DNS relay service, I meant having a way of programmatically manipulating the DNS table, pointing the internal subdomain to the custom one. I'm curious about how you implemented this because the TTL is practically instant.
Errr.. why would you want to point the subdomain to the custom domain? Currently, users can CNAME an external domain to the FreeFlarum subdomain, which seems to work fine? The only caveat are apex domains, as explained by @clarkwinkelmann. However, this case is very rare and even then, can be resolved by using specific DNS providers such as Cloudflare.
DanielTheGeek There are many ways I can help, as I'm a full stack dev...
That's an awesome offer! FYI, I want to open source large parts of FF.com so that many people can collaborate. However, I need to rewrite a bit of the core (Python) first and I am awaiting the release of beta8 first.
User34 I think it is good as that, amiright?
DNS was (eventually) good, but you had to connect your domain through https://www.freeflarum.com/settings. I did that for you, it is working now! https://flarum.twistforums.cf/