Too Long; Didn't Read
I consider a module to be a kinda “first-class citizen” in my code ever since I’ve read the <a href="https://www.amazon.com/Domain-Driven-Design-Tackling-Complexity-Software/dp/0321125215" target="_blank">DDD book</a>. Probably finding the module boundaries is the second most important thing after <a href="https://medium.com/@wrong.about/how-to-define-service-boundaries-251c4fc0f205" target="_blank">finding service boundaries</a>.