gistfile1.txt

# Ruby
module App
  extend self

  def call(env)
    [
      200,
      { 'Content-Type' => 'application/json' },
      ['{"message": "Hello World"}']
    ]
  end
end

# Js
var http = require("http");

http.createServer(function(request, response) {
  response.writeHead(200, {"Content-Type": "text/plain"});
  response.write('{ "message": "Hello World!"}');
  response.end();
}).listen(8888);