GZIP all files in a built Jekyll Project.

jekyll_gzip.rb

require 'zlib'

Dir[File.join('_site', '**', '*')].reject { |p| File.directory? p }
.each do |oldfile|
  old_file_text = File.read(oldfile)
  open(oldfile, 'wb') do |file|
    gzip = Zlib::GzipWriter.new(file)
    gzip << old_file_text
    gzip.close
  end
end