http://www.virtuouscode.com/2014/04/29/rake-part-7-multitask/
https://news.ycombinator.com/item?id=319337
http://www.virtuouscode.com/2014/04/24/rake-part-4-pathmap/
https://www.stuartellis.name/articles/rake/
https://coderwall.com/p/8yl45w/creating-a-test-rake-task-with-minitest
https://gitlab.com/auto-devops-examples/minimal-ruby-app/blob/master/rakefile.rb
https://github.com/kennethkalmer/daemon-kit
https://github.com/nesquena/dante
http://michalorman.com/2015/03/daemons-in-rails-environment/
https://cds.cern.ch/record/341074/files/9712161.pdf
https://mathinsight.org/curl_gradient_zero
https://mathinsight.org/curl_idea
https://mathinsight.org/curl_subtleties