I'm amazed that their architecture doesn't include a CDN. These days I expect nearly all high traffic websites to make use of a CDN for all kinds of content, even content that's not cached.
They cited Cloudflare not being used due to privacy concerns. It'd be interesting to hear more about that, as well as why other CDNs weren't worth evaluating too.
What they are doing is unfortunately not legal. There were precedents of Cloudflare ratting out manga site operators before which have led to arrests [1] (the person who ran mangamura got a 3 year sentence and a $650k fine [2]). And at some point they were going after mangadex via the same way too [3].
A lot of their infrastructure design choices should be viewed with OPSEC constraints in mind.
Which is interesting considering they take no issue with sites like KiwiFarms which harass people to literal death, terrorist groups, criminals (carders, phishers, etc.), racists & other forms of hate speech.
I guess it all depends on how much money you bring in for them really.
It's effectively a warez site. There's a reason why they host in the places they do and can't be too picky about providers.
CF will also pass through things like DMCAs easily.
Based on their sidebar, it's probably hosted at Ecatel or whatever they are called now (cybercrime host) via Epik as a reseller, the provider famous for hosting far-right stuff.
They do have a crowdsourced CDN called Mangadex@Home. I participated in it from last year until the site was hacked. The aggregate egress speed was around 10 Gbps.
The NSFW counterpart of MD also has a CDN appropriately named Hentai@Home run by volunteers.
These 2 sites are the only ones rolling their own CDN for free that I know.
I think the usual argument re: Cloudflare on the privacy front is the fact that they pretty aggressively fingerprint users, and will downgrade or block traffic originating from VPNs or some countries. This is a natural side effect of those things often being tied to abusive traffic, and a lot of it is likely configurable (at least on their paid plans) but it often comes up around this.
The CDN part is kind of pointless because they can't really have nodes in large parts of the western world since.. it's a warez site. The CDN providers will get takedowns, requests to reveal the backing origin, etc. You can't use a commodity CDN provider for this.
Latency makes a bigger impact on UX than throughput for general browsing. A TLS handshake can be multiple roundtrips that greatly benefit from lower latency, especially mobile devices.
Modern CDNs also provide lots of functionality from security (firewall, DDOS) to application delivery (image optimization, partial requests).
That's the raison d'être of nginx, so it is performant for this kind of thing. However, the advantage of a CDN is that they have points of presence around the world, so your user in Singapore doesn't have to do a trip around the world to get to your nginx on a physical box in Lisbon.
They cited Cloudflare not being used due to privacy concerns. It'd be interesting to hear more about that, as well as why other CDNs weren't worth evaluating too.