Github costs $7/mo. Is it more economical than that? Can you seriously say that you can achieve higher cross-region redundancy, for both your instances and storage, than Github can, at a price less than $7/mo?
The only way I can think of accomplishing it is to make use of GCP's free f1.micro instance, so you can spin up two of those for pretty cheap in different regions ($3.88/mo). Have DNS hosted somewhere that can resolve to each of your two instances at random ($12/year? Lets's say $1/mo). Then you have instance storage; good luck finding globally redundant block storage for practically unlimited repositories, with backups, for $2.12/mo. Let's just leave network egress charges out of it, since those would be marginal.
And let's go ahead and say I value my free time at a conservative $30/hr. It takes me an hour to set this thing up and maintain it every year; horribly conservative. That's an additional $2.50/mo.
Maybe you can do it. It isn't laughably economical.
