Create a CSV in memory then add it to an encrypted zip file

encrypted_zip.rb

require 'zipruby'
require 'csv'

csv = CSV.generate do |csv|
  csv << ['i', '2i']

  1.upto(10) do |i|
    csv << [i, i*2]
  end
end

Zip::Archive.open('encrypted_csv.zip', Zip::CREATE) do |zip|
  zip.add_buffer('nums.csv', csv)
  zip.encrypt 'password'
end