```ruby
CarrierWave.configure do |config|

  case Rails.env.to_sym

  when :development
    config.storage = :file
    config.root = File.join(Rails.root, 'public')

  when :production
    config.storage = :s3
    config.s3_access_key_id = ENV['S3_KEY_ID']
    config.s3_secret_access_key = ENV['S3_SECRET_KEY']
    config.s3_bucket = ENV['S3_BUCKET']
    # config.s3_cname = 'ENV['S3_CNAME']
  end

end
```

Mark a note about how to handle file uploads for persistence
user
```ruby
# TODO: Make this store to RAILS_ROOT/permanent

# On bushido, the app directory is destroyed on every update, so everything is lost.
# The only place this doesn't happen is the RAILS_ROOT/permanent folder.
# Also, RAILS_ROOT/permanent/store is symlinked to RAILS_ROOT/public/store on every update,
# so store your publicly-accessible files here (e.g. templates, etc.)

CarrierWave.configure do |config|

  case Rails.env.to_sym

  when :development
    config.storage = :file
    config.root = File.join(Rails.root, 'public')

  when :production
    config.storage = :s3
    config.s3_access_key_id = ENV['S3_KEY_ID']
    config.s3_secret_access_key = ENV['S3_SECRET_KEY']
    config.s3_bucket = ENV['S3_BUCKET']
    # config.s3_cname = 'ENV['S3_CNAME']
  end

end
```
assistant