Funny how different situations can be. I can't get an IPv6 address unless I pay for insanely expensive business tiers.

Roasted

I wonder if they ever contacted github support, and what their answer was - rather than only posting on a public forum github doesn't feel compelled to answer or make official responses to.

I always use Github to check if my IPv4 DNS works lol (using ping). So it's definitely a feature /s

If you live in the USA you don't suffer from the problem it solves because you have ~5 IP v4 addresses per capita (totaling to 41% of all the IP v4 addresses), and likewise many european countries have ~2 per capita (although there are expeptions like Italy and Spain which are a bit under 1 per capita). However many other countries don't have such luxury, for example in india there's one for every 36 people, which is obviously not enough and thus they have to either use NAT everywhere or switch to IPv6.

Same. I’m hearing it’s a must-have for like 15 years now. It still obviously isn’t a real must-have.

You may have.

For example, T-Mobile in many places gives you an IPv6 address and uses CG-NAT for IPv4 — meaning you don’t have your own IPv4, but you do have a few quintillion “real” IPv6’s to yourself.

I used to study networking, albeit at a pretty beginner level. IPv6 has been around for nearly 30 years at this point, so I'd be surprised if the hardware github uses doesn't support it. The impression I got was that it's pretty easy to extend an IPv4 address space so there isn't any rush to make a large scale move to IPv6 everywhere.

It's not generally a hardware problem. It's a resourcing problem. Companies like GitHub will have complex software and architecture. IPv6 requires them to get a pool of IP addresses, come up with an IP address management strategy, make sure all hosts have IPv6 addresses meaning that now provisioning systems and tooling to management DNS has to plumb IPv6 addresses through too.

Then the software stack has to support it. Maybe their fraud detection or auditing systems have to now support IPv6 which means changes to API schemas.

None of this is a good reason why they shouldn't do it, but I've had to make similar decisions at my job as a software engineer on what looks to be simple but actually requires changes across systems.

Name:   gitlab.com
Address: 172.65.251.78
Name:   gitlab.com
Address: 2606:4700:90:0:f22e:fbec:5bed:a9b9

But why ?

Yeah that's probably how your phone gets everywhere, since mobile networks are usually IPv6