The fact is the complexity in most valuable systems is interacting with other external systems. Your system can be as type safe as it wants. It will never be t

The fact is the complexity in most valuable systems is interacting with other external systems. Your system can be as type safe as it wants. It will never be type safe when tied to the systems of other companies, no matter what they say, or how they say their apis are supposed to work (assuming you have documented apis at all). Being able to iterate quickly and test those connections is far more valuable to most businesses. At a certain scale, it probably flips, but at that point you're a huge company.