The system now used to serve GoDaddy's Website Builder content is written in node, deployed to clusters behind load balancers, and from there connecting to Cassandra clusters for the data... iirc, the average turn around time for a given request (including dynamic ones) is less than 12ms from the node server receiving the request to delivering the response, under a load of many millions of requests per second to the system.

Disclosure, I worked at GD in Website Builder when this was being developed, but haven't been there for over 2 years now.