Tidy First?

By Kent Beck

Kent Beck, the creator of Extreme Programming and a pioneer of software patterns, explores the art of making small, structural changes to code before changing its behavior. Tidy First? is the first in a series on empirical software design, and it asks a deceptively simple question: should you clean up the code before making your next change?

The book introduces "tidyings" — small, safe, reversible code improvements like extracting helpers, reordering statements, or removing dead code. These tidyings are not refactorings in the traditional sense; they are quick, low-risk moves that make the next behavioral change easier and safer.

Beyond the practical techniques, Kent Beck connects software design to economics and optionality, showing how the decision of when to tidy is ultimately about managing the cost of change over time. A must-read for anyone who wants to write code that is easier to understand, change, and extend.