Rack

Upcase
1

Rack is the glue that binds application frameworks like Rails and Sinatra to web servers like thin and puma. In this episode Joël Quenneville takes us on a tour of Rack and shows us how we can take advantage of the Rack pattern to build more robust and decoupled applications.

This is a companion discussion topic for the original entry at https://thoughtbot.com/upcase/videos/rack
2

You have an error in Rack::Builder section
take a look at this. typo in sleep function

app = -> (env) do
  slee 3
  [ 200, { "Content-Type" => "text/plain" }, ["Hello World\n"] ]
end
3

Thanks for pointing that out! All fixed now.