Whenever one builds a new application, there is a challenge in testing it at scale: where do you get sufficient data to generate a realistic “data shape?”. Snowfakery is a Domain Specific Language that builds on and deeply integrates with Python to excel at this task. This talk will describe how to build an “interpreter” for a YAML-based language in Python, including how we leverage Python-specific superpowers such as Jinja templating and easy dynamic loading. Slides: https://docs.google.com/presentation/d/17VmU_mW2lQGsj_ChJHB4nG9qmhGbVwEtqQTvweBFTAQ/edit?usp=sharing