S. Demeyer, S. Ducasse, and O. Nierstrasz, “Reengineering Patterns,” in Object-Oriented Reengineering Patterns, Elsevier, 2003, pp. 1–14. doi: 10.1016/B978-155860639-5/50006-7.
scg.unibe.ch 
and github
# Foreword by Martin Fowler
So this book is important because it’s written from the perspective of what to do with an imperfect yet valuable code base. I also like the fact that it’s based on an effective mix of academic and industrial work. I visited the FAMOOS group in their early days during a chill early winter in Bern. I liked the way that they cycled between the field and the lab, trying out ideas on real projects, coming back to the lab to reflect.
# What Is This Book? This book grew out of the realization that the most interesting and challenging side of software engineering is not developing brand new software systems, but rejuvenating existing systems.