Simple image optimisation in image_optim

assets.rake

# lib/tasks/assets.rake
require 'image_optim'
require 'image_optim/runner'
namespace :assets do
  desc 'Runs image_optim on the assets.'
  task :optimize do
    image_optim = ImageOptim::Runner.new(recursive: true)
    image_optim.run!(Dir['app/**/*.{svg,jpg,png,jpeg,gif}'])
  end
end