Given the right tools, you should be able to handle double the max load that they are expecting given a beefy enough server. Their architecture is a bit too complex for my taste, but given that reddit is written in python it is not surprising that this was the direction that they took. You could use tsung (http://tsung.erlang-projects.org/1/01/about/) to test workloads at that level. This would be a pretty straightforward project to build with erlang/elixir's gen_server abstraction.