This might help others who decide to use fastest_csv with sidekiq. Known bug that `alias_method` (used in fastest_csv) will cause sidekiq to crash (https://github.com/mperham/sidekiq/issues/2139). Best way around it when working inside a sidekiq worker is to avoid using FastestCSV#shift such as by: ``` ruby csv_file = File.open('your/csv/file/here.csv', 'rb') shift(csv_file) # manually handle it instead def shift csv_file if line = csv_file.gets line.parse_csv else nil end end ```