A preview of Square Workflow, presented at droidconNYC 2018.
https://www.youtube.com/watch?v=cw9ZF9-ilac
Original deck: https://docs.google.com/presentation/d/1tn4CxpoZHADxvf0mgJ57Yt7VQBCQVPpMKaM4vSDxSbU/edit#slide=id.g4088c7565d_2_5
https://github.com/square/workflow/