Infrastructure-as-a-Service (IaaS) is fairly well-known by now. Whether Amazon, OpenStack, Eucalyptus or any proprietary offerings, the basics are all the same: virtual machines, key-value buckets etc. Not so for Platform-as-a-Service (PaaS). There are lots of vendors, but the architectures and basic assumptions behind their products differ widely — and those differences are less well-known than […]