Carola Lilienthal

Software architecture metrics are key to the maintainability and architectural quality of a software project and they can warn you about dangerous accumulations of architectural and technical debt early in the process. In this practical book, leading hands-on software architects share case studies to introduce metrics that every software architect should know. This isn't a book about theory. It's more about practice and implementation, about what has already been tried and worked. Detecting software architectural issues early is crucial for the success of your software: it helps mitigate the risk of poor performance and lowers the cost of repairing those issues. Written by practitioners for software architects and software developers eager to explore successful case studies, this guide will help you learn more about decision and measurement effectiveness. Through contributions from 10 prominent practitioners, this book shares key software architecture metrics to help you set the right KPIs and measure the results. You'll learn how to: Measure how well your software architecture is meeting your goals Choose the right metrics to track (and skip the ones you don't need) Improve observability, testability, and deployability Prioritize software architecture projects Build insightful and relevant dashboards

Legacy systems slow down innovation, increase maintenance costs, and create misalignment between business goals and technical delivery. Domain-Driven Transformation offers a clear, risk-aware path to modernizing complex applications using principles from domain-driven design (DDD) and modular architecture. Authors Henning Schwentner and Carola Lilienthal guide software architects, technical leads, and senior engineers through practical, incremental strategies to evolve legacy systems without the disruption of a full rewrite. With a focus on collaboration, modularity, and strategic refactoring, this book helps you assess architectural maturity using the modularity maturity index (MMI) and identify transformation opportunities through modeling techniques like event storming and domain storytelling. Packed with real-world examples and case-driven insights, you'll uncover the tools needed to build systems that scale, support business agility, and remain resilient over time. Assess your system's modularity and architectural health with the MMI Apply strategic and tactical DDD to manage complexity Break apart monolithic systems into domain-aligned components Use collaborative modeling techniques to align teams and clarify design Refactor incrementally with patterns that reduce risk while delivering value

Today's programmers don't develop software systems from scratch. Instead, they spend their time fixing, extending, modifying, and enhancing existing software. Legacy systems often turn into an unwieldy mess that becomes increasingly difficult to modify, and with architecture that continually accumulates technical debt.Carola Lilienthal has analyzed more than 300 software systems written in Java, C#, C++, PHP, ABAP, and TypeScript and, together with her teams, has successfully refactored them. This book condenses her experience with monolithic systems, architectural and design patterns, layered architectures, domain-driven design, and microservices.With more than 200 color images from real-world systems, good and sub-optimal sample solutions are presented in a comprehensible and thorough way, while recommendations and suggestions based on practical projects allow the reader to directly apply the author's knowledge to their daily work."Throughout the book, Dr. Lilienthal has provided sound advice on diagnosing, understanding, disentangling, and ultimately preventing the issues that make software systems brittle and subject to breakage. In addition to the technical examples that you'd expect in a book on software architecture, she takes the time to dive into the behavioral and human aspects that impact sustainability and, in my experience, are inextricably linked to the health of a codebase. She also expertly zooms out, exploring architecture concepts such as domains and layers, and then zooms in to the class level where your typical developer works day-to-day. This holistic approach is crucial for implementing long-lasting change."From the Foreword of Andrea GouletCEO, Corgibytes,Founder, Legacy Code Rocks