O_o ? But this is what happens for sure in filterworker [line 99](https://github.com/logstash/logstash/blob/master/lib/logstash/filterworker.rb#L99) as the new event is added to the events list, then it will finally be processed by the events.each and thus will go in the full  @filters.each do |filter|. I will make a quick spec test to prove it.