I started using Carrierwave, and I found out that it stores temporary files at multiple places depending on whether it is testing or delayed job.
If it is done during testing(rspec), the temp files will be at
config.cache_dir option you can set in 'config/initializers/carrierwave.rb'. But it is relative to '/public'. Looks like you should do that in your uploaders:
class MyUploader < CarrierWave::Uploader::Base def cache_dir # should return path to cache dir Rails.root.join 'tmp/uploads' end end