It’s a mix. A lot of their PaaS services are Microsoft Service Fabric under the hood, running on Windows Server.

This is vaguely like Kubernetes but worse.

So for example they can’t do zone affinity for traffic routing, so all of their zone-redundant traffic ping-pongs between data centres like crazy.

If you use just a couple of layers of their services like private endpoints and app gateway, you can expect to see 15ms response times.