Continuous Architecture in Practice: Software Architecture in the Age of Agility and DevOps (Addison-Wesley Signature Series (Vernon))

353 Pages·2021·6.445 MB·English

by  Murat Erder, Pierre Pureur, Eoin Woods

Continuous Architecture
Principles
Principle 1: Architect products; evolve from projects to
products.
Principle 2: Focus on quality attributes, not on functional
requirements.
Principle 3: Delay design decisions until they are absolutely
necessary.
Principle 4: Architect for change—leverage the “power of
small.”
Principle 5: Architect for build, test, deploy, and operate.
Principle 6: Model the organization of your teams after the
design of the system you are working on.
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Praise for Continuous Architecture in Practice
“I am continuously delighted and inspired by the work of these authors. Their first
book laid the groundwork for understanding how to evolve the architecture of a
software-intensive system, and this latest one builds on it in some wonderfully
actionable ways.”
—Grady Booch, Chief Scientist for Software Engineering, IBM Research
“Continuous Architecture in Practice captures the key concerns of software archi-
tects today, including security, scalability and resilience, and provides valuable
insights into managing emerging technologies such as machine/deep learning and
blockchain. A recommended read!”
—Jan Bosch, Professor of Software Engineering and Director of the
Software Center at Chalmers University of Technology, Sweden
“Continuous Architecture in Practice is a great introduction to modern-day software
architecture, explaining the importance of shifting architectural thinking ‘left’ in order
to form a set of firm foundations for delivery and continuous architecture evolution.
I really liked the coverage of quality attributes, with a real-world case study providing a
way to highlight the real-world complexities of the trade-offs associated with different
solutions. The set of references to other material is impressive too, making this book
incredibly useful for readers new to the domain of software architecture.”
—Simon Brown, author of Software Architecture for Developers
“Focus on software architecture can get lost when talking about agile software prac-
tices. However, the importance of architecture in software systems has always been
and continues to be relevant. The authors address this important topic with their
second book on Continuous Architecture. This time they provide advice on aspects
that will make or break your system, from data to security, scalability and resilience.
A much recommended book that offers practical guidance for anyone developing
systems in today’s rapidly evolving technology landscape.”
—Ivar Jacobson
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“This book continues the journey where its predecessor left off. Software today is
never-ending, and true to its name, this book looks at continuing trends and applies
Continuous Architecture principles using practical examples. The authors avoid the
trap of picking popular tools whose relevance quickly expire, choosing instead to
look at those trends that should influence and shape architecture decisions. This
book will be essential reading for any person wanting to design and architect soft-
ware systems that continue to keep up with the times.”
—Patrick Kua, CTO Coach and Mentor
“In the two-decade-old conflict between ‘big upfront design’ and ‘emergent architec-
ture,’ software architects have often had a hard time finding a meaningful compro-
mise. In Continuous Architecture in Practice, Erder, Pureur, and Woods provide them
with a proven path. This book is a big leap forward: I liked the more systematic use
of architectural tactics—a design artifact that has not been exploited as much as it
should. And that they brought the concept of architectural technical debt to a more
prominent position in the process of making technical and managerial decisions.”
—Philippe Kruchten, software architect
“It’s high time that Agile architecture evolved from oxymoron to what it really needs
to be, a lean, enabling practice that accelerates development and delivery of the next
generation of resilient and scalable enterprise class systems. Continuous Architec-
ture in Practice is another quantum step toward that goal and provides practical
guidance toward creating designs that are responsive to changing requirements and
technologies.”
—Dean Leffingwell, creator of SAFe
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Pearson Addison-Wesley
Signature Series
Visit informit.com/awss/vernon for a complete list of available publications.
The Pearson Addison-Wesley Signature Series provides readers with
practical and authoritative information on the latest trends in modern
technology for computer professionals. The series is based on one
simple premise: great books come from great authors.
Vaughn Vernon is a champion of simplifying software architecture and
development, with an emphasis on reactive methods. He has a unique
ability to teach and lead with Domain-Driven Design using lightweight
tools to unveil unimagined value. He helps organizations achieve
competitive advantages using enduring tools such as architectures,
patterns, and approaches, and through partnerships between business
stakeholders and software developers.
Vaughn’s Signature Series guides readers toward advances in software
development maturity and greater success with business-centric
practices. The series emphasizes organic refinement with a variety
of approaches—reactive, object, and functional architecture and
programming; domain modeling; right-sized services; patterns; and
APIs—and covers best uses of the associated underlying technologies.
Make sure to connect with us!
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Pearson Addison-Wesley
Signature Series
Continuous
Architecture
in Practice
Visit informit.com/awss/vernon for a complete list of available publications.
Software Architecture in the
The Pearson Addison-Wesley Signature Series provides readers with
Age of Agility and DevOps
practical and authoritative information on the latest trends in modern
technology for computer professionals. The series is based on one
simple premise: great books come from great authors.
Vaughn Vernon is a champion of simplifying software architecture and
development, with an emphasis on reactive methods. He has a unique
ability to teach and lead with Domain-Driven Design using lightweight Murat Erder
tools to unveil unimagined value. He helps organizations achieve
Pierre Pureur
competitive advantages using enduring tools such as architectures,
Eoin Woods
patterns, and approaches, and through partnerships between business
stakeholders and software developers.
Vaughn’s Signature Series guides readers toward advances in software
development maturity and greater success with business-centric
practices. The series emphasizes organic refinement with a variety
of approaches—reactive, object, and functional architecture and
programming; domain modeling; right-sized services; patterns; and
APIs—and covers best uses of the associated underlying technologies.
Boston • Columbus • New York • San Francisco • Amsterdam • Cape Town
Dubai • London • Madrid • Milan • Munich • Paris • Montreal • Toronto • Delhi • Mexico City
São Paulo • Sydney • Hong Kong • Seoul • Singapore • Taipei • Tokyo
Make sure to connect with us!
informit.com/socialconnect
9780136523567_Print.indb 5 20/04/21 7:28 PM
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Library of Congress Control Number: 2021933714
Copyright © 2021 Pearson Education, Inc.
Cover image: KMNPhoto / Shutterstock
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Page 38, Figure 2.6: Kruchten, P., R. Nord & I. Ozkaya. Managing Technical Debt: Reducing Friction in Software
Development, 1st Ed., 2019. Reprinted by permission of Pearson Education, Inc.
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ISBN-13: 978-0-13-652356-7
ISBN-10: 0-13-652356-0
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To Hakan, Ozan, and Pinar
—M.E.
To Kathy
—P.P.
To my family
—E.W.
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Contents
Foreword by Vaughn Vernon, Series Editor . . . . . . . . . . . . . . . . . . . . . . . . . xv
Foreword by Kurt Bittner . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xix
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xxi
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .xxv
About the Authors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xxvii
Chapter 1: Why Software Architecture Is More Important than Ever . . . . . . . 1
What Do We Mean by Architecture? ............................. 1
Software Industry Today ...................................... 3
Current Challenges with Software Architecture .................... 5
Focus on Technology Details Rather than Business Context .... 6
Perception of Architects as Not Adding Value ............... 6
Architectural Practices May Be Too Slow ................... 7
Some Architects May Be Uncomfortable with Cloud
Platforms .......................................... 8
Software Architecture in an (Increasingly) Agile World .............. 8
The Beginnings: Software Architecture and Extreme
Programming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Where We Are: Architecture, Agility, and
Continuous Delivery ................................ 10
Where We May Be Going .............................. 11
Introducing Continuous Architecture ........................... 11
Continuous Architecture Definition ...................... 13
Continuous Architecture Benefits ........................ 15
Applying Continuous Architecture ............................. 17
Continuous Architecture Provides a Set of Principles
and Tools ......................................... 17
Introduction to the Case Study ................................ 19
Case Study Context: Automating Trade Finance ............ 20
Summary ................................................. 22
ix
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