config.ru

# [config.ru]
#
# puma
# curl http://localhost:9292/
#
# Note chrome buffers like 1024 or so... meaning the first lots will look missing.

use Rack::Chunked
run lambda { |env|

  def each
    10.times do |i|
      n = 2

      str = "#{i}: #{('a'..'z').sort_by { rand }.take(rand(26)).join}\n"
      yield str
      sleep 1
    end
  end

  [200, {}, self]
}

Added some random data and curl --raw to show the chunking protocol.