I get that it's not supposed to be a technical blog post, but some details would've been nice. What platform are they using? Major Cloud Providers? How'd they

I get that it's not supposed to be a technical blog post, but some details would've been nice. What platform are they using? Major Cloud Providers? How'd they solve load balancing? HA-Proxy? Nginx? What tuning had been done? What database are they using? What'd they use to determine the queries? What'd they end up doing with the hot queries? VPN tunnels? What are they using? What's the underlying network? More importantly, what challenges did they experience while scaling up? What things had to be fundamentally rewritten? Maybe the author will see this and can answer some of the questions here.