[jonmoore]

Indeed, and tools like dep-tree provide a combination of 1) making module structure visible 2) making rules about this structure concrete and 3) automatically checking for rule violations.

These all help to lower the cognitive barrier to learning and maintaining the code base effectively. For developers new to the code base they help with learning and for those more experienced they help with ongoing design and maintenance.

Most long-lived code bases I've seen have adopted or built such tooling at some point, often with tools customized to the code base. For example in one large code base (c. 250 devs) we built tooling that simulated and helped optimize the changes to implement a major refactor of the overall module structure.