> If I were starting a major distributed systems project today that required serious uptime and scalability, I'd start on Service Fabric.

I'd start with Erlang. The track record of Erlang for those parameters is just about unbeatable. And then there is the very careful way in which they deal with backwards compatibility, which is a major asset for any long lived project. If your projects live (or are intended to live) for a decade or more such details really matter.