Seeing types where others don't

The author describes a multi-year journey of inferring types from jq programs to produce better error messages. They discuss the tension between static and dynamic typing, noting that while types provide safety and refactoring confidence, dynamic typing better suits exploratory programming tasks like processing JSON or prototyping. The author highlights that all programs inherently have types even in dynamic languages, and was motivated by jq's poor error messages to explore static type inference for dynamically typed code.