Keystonejs comes pre-built with Jade interpretation, so rendering Jade written by users is a piece of cake.
The Quips web-server is deployed on the EC2 cluster using Elastics Beans Talk (EBT) of AWS. EBT also allows us to monitor the CPU amd memory usage of our cluster to garantee enough availability. Auto-scaling is activated on our cluster to allow adding of servers if the workload increases.
S3 is used to store the Javascript and Jade files attached to each project when they are deployed.