Strategic Monoliths and Microservices

Strategic Monoliths and Microservices helps business decision-makers and technical team members collaborate to clearly understand their strategic problems, and identify their optimal architectural approaches, whether those turn out to be distributed microservices, well-modularized monoliths, or coarse-grained services partway between the two. Writing for MBA and IT students alike, leading software architecture expert Vaughn Vernon and Tomasz Jasku+éa guide you through making balanced architecture compositional decisions based on need and purpose rather than popular opinion, so you can maximize business value and deliver systems that evolve more easily. Throughout, the authors provide realistic application examples, showing how to construct well-designed monoliths that are maintainable and extensible, and how to decompose massively tangled legacy systems into truly effective microservices.

Foreword xiiiPreface xviiAcknowledgments xxvAbout the Authors xxxiPart I: Transformational Strategic Learning through Experimentation 1Executive Summary 3Chapter 1: Business Goals and Digital Transformation 7Digital Transformation: What Is the Goal? 8Why Software Goes Wrong 11Your Enterprise and Conway's Law 18(Re)Thinking Software Strategy 24Are Monoliths Bad? 30Are Microservices Good? 31Don't Blame Agile 34Getting Unstuck 36Summary 37References 38Chapter 2: Essential Strategic Learning Tools 39Making Decisions Early and Late, Right and Wrong 40Culture and Teams 43Modules First 51Deployment Last 55Everything in Between 57Where Is Your Spaghetti and How Fast Does It Cook? 70Strategic Architecture 70Applying the Tools 72Summary 75References 75Chapter 3: Events-First Experimentation and Discovery 77Commands and Events 78Rapid Learning with EventStorming 81Applying the Tools 92Summary 99References 100Part II: Driving Business Innovation 101Executive Summary 103Chapter 4: Reaching Domain-Driven Results 109Domains and Subdomains 111Summary 115References 116Chapter 5: Contextual Expertise 117Bounded Context and Ubiquitous Language 117Core Domain 121Supporting Subdomains, Generic Subdomains, and Technical Mechanisms 123Business Capabilities and Contexts 125Not Too Big, Not Too Small 128Summary 129References 130Chapter 6: Mapping, Failing, and Succeeding--Choose Two 131Context Mapping 131Topography Modeling 151Ways to Fail and Succeed 154Applying the Tools 158Summary 163References 164Chapter 7: Modeling Domain Concepts 165Entities 166Value Objects 167Aggregates 168Domain Services 169Functional Behavior 170Applying the Tools 173Summary 173References 174Part III: Events-First Architecture 175Executive Summary 177Chapter 8: Foundation Architecture 181Architectural Styles, Patterns, and Decision Drivers 183Quality Attributes 196Applying the Tools 206Summary 207References 208Chapter 9: Message- and Event-Driven Architectures 211Message- and Event-Based REST 216Event-Driven and Process Management 220Event Sourcing 223CQRS 227Serverless and Function as a Service 229Applying the Tools 231Summary 231References 232Part IV: The Two Paths for Purposeful Architecture 233