20:1 web tool: Phoenix on Elixir (on Erlang VM)

use-case mentioned during interview:
20 servers with Ruby on Rails replaced with one server with Phoenix on Elixir

podcast: Elixir and Phoenix with Chris McCord @ .NET Rocks!

• Elixir Language 
• Phoenix for Elixir 
• Getting Started with Erlang 
• Ecto Data Access for Elixir  
• Chris' Blog 
• Metaprogramming Elixir 
• Bleacher Report 
• Heroku
• Elixir on the Raspberry Pi 2

Elixir vs Ruby Showdown - Phoenix vs Rails
"Phoenix showed 10.63x more throughput over Rails when performing the same task, with a fraction of CPU load"

Ruby vs Elixir -- An Unfair Fight (and Elixir wins) — Big Data Little Geek

Elixir - The next big language for the web