Managing Technical Debt: Reducing Friction in Software Development

270 Pages·2019·8.929 MB·English

by  Philippe Kruchten, Robert Nord, Ipek Ozkaya

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Managing Technical Debt
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The SEI Series in Software Engineering
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Managing Technical Debt
Reducing Friction in Software Development
Philippe Kruchten
Robert Nord
Ipek Ozkaya
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Executive Editor
Kim Spenceley
The SEI Series in Software Engineering Development Editor
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ISBN-13: 978-0-13-564593-2
ISBN-10: 0-13-564593-X
1 19
To Sylvie, Nicolas, Alice, Zoé, Harmonie,
Claire, and Henri
—PK
To Victoria and Richard
—RN
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To Ibrahim, Zeynep, and Zehra
—IO
Contents at a Glance
Foreword . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xiii
Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xv
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xix
About the Authors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xxi
About the Contributors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xxiii
Acronyms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xxv
SEI Figures for Managing Technical Debt . . . . . . . . . . . . . . . . . . . . . . . . . .xxvii
Part I: Exploring the Technical Debt Landscape . . . . . . . . . . . . 1
Chapter 1: Friction in Software Development . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
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Chapter 2: What Is Technical Debt? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Chapter 3: Moons of Saturn—The Crucial Role of Context . . . . . . . . . . . . . . . 37
Part II: Analyzing Technical Debt . . . . . . . . . . . . . . . . . . . . . . 49
Chapter 4: Recognizing Technical Debt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Chapter 5: Technical Debt and the Source Code . . . . . . . . . . . . . . . . . . . . . . . . 65
Chapter 6: Technical Debt and Architecture . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
Chapter 7: Technical Debt and Production . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
Part III: Deciding What Technical Debt to Fix . . . . . . . . . . . 115
Chapter 8: Costing the Technical Debt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117
Chapter 9: Servicing the Technical Debt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131
vi
Contents at a Glance vii
Part IV: Managing Technical Debt Tactically
and Strategically . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149
Chapter 10: What Causes Technical Debt? . . . . . . . . . . . . . . . . . . . . . . . . . . . 151
Chapter 11: Technical Debt Credit Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167
Chapter 12: Avoiding Unintentional Debt . . . . . . . . . . . . . . . . . . . . . . . . . . . . 179
Chapter 13: Living with Your Technical Debt . . . . . . . . . . . . . . . . . . . . . . . . . 195
Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 207
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 209
Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 217
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Contents
Foreword . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xiii
Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xv
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xix
About the Authors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xxi
About the Contributors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xxiii
Acronyms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xxv
SEI Figures for Managing Technical Debt . . . . . . . . . . . . . . . . . . . . . . . . . .xxvii
Part I: Exploring the Technical Debt Landscape . . . . . . . . . . . . 1
Chapter 1: Friction in Software Development . . . . . . . . . . . . . . . . . . . . . . . . 3
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The Promise of Managing Technical Debt . . . . . . . . . . . . . . . . . . . . . . . . 3
Technical Debt A-B-C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Examples of Technical Debt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Your Own Story About Technical Debt? . . . . . . . . . . . . . . . . . . . . . . . . 11
Who Is This Book For? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Principles of Technical Debt Management . . . . . . . . . . . . . . . . . . . . . . 13
Navigating the Concepts of the Book . . . . . . . . . . . . . . . . . . . . . . . . . . 14
What Can You Do Today? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
For Further Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Chapter 2: What Is Technical Debt? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Mapping the Territory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
The Technical Debt Landscape . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Technical Debt Items: Artifacts, Causes, and Consequences . . . . . . . . 22
Principal and Interest . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Cost and Value . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Potential Debt versus Actual Debt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
The Technical Debt Timeline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
What Can You Do Today? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
For Further Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
ix