What is the most Wicked (promise|async)/stream based code that you have ever done?

Angel Daniel Munoz Gonzalez - Jun 6 '18 -

I remember doing a naïve (I guess, I never requested a code review from someone else) implementation of a stream which used a mongodb cursor to process thousands of registries into another database
basically I mixed streams, eventemmiters (inherited of the stream), some generators and promise based code.