Working Effectively With Legacy Code

Get more out of your legacy systems: more performance, functionality, reliability, and manageability Is your code easy to change? Can you get nearly instantaneous feedback when you do change it? Do you understand it? If the answer to any of these questions is no, you have legacy code, and it is draining time and money away from your development efforts. In this book, Michael Feathers offers start-to-finish strategies for working more effectively with large, untested legacy code bases. This book draws on material Michael created for his renowned Object Mentor seminars: techniques Michael has used in mentoring to help hundreds of developers, technical managers, and testers bring their legacy systems under control. The topics covered include Understanding the mechanics of software change: adding features, fixing bugs, improving design, optimizing performance Getting legacy code into a test harness Writing tests that protect you against introducing new problems Techniques that can be used with any language or platform—with examples in Java, C++, C, and C# Accurately identifying where code changes need to be made Coping with legacy systems that aren't object-oriented Handling applications that don't seem to have any structure This book also includes a catalog of twenty-four dependency-breaking techniques that help you work with program elements in isolation and make safer changes.

Michael Feathers offers start-to-finish strategies for working more effectively with large, untested legacy code bases. This book draws on material Michael created for his own renowned Object Mentor seminars: techniques Michael has used in mentoring to help hundreds of developers, technical managers, and testers bring their legacy systems under control. This book also includes a catalog of twenty-four dependency-breaking techniques that help you work with program elements in isolation and make safer changes.

"This is a warm and reassuring book that will equip you to read, understand, and update legacy code in any language." --Kate Gregory "It is easy to forget that outside the world of software development, the word legacy has another meaning. A positive meaning, a gift of wealth from the past to the present for the future. This book will help you reclaim the word." --Kevlin Henney If you're like most software developers, you have to deal with legacy code. But working with legacy code is challenging! This book will teach you how to be happy, efficient and successful when working with legacy code. Here are the skills that The Legacy Code Programmer's Toolbox will teach you: - how to deal with legacy code efficiently and with a positive approach, - 10 techniques how to understand legacy code, - 5 ways to reduce the size of long functions, - a technique to turn legacy code to your advantage to improve your programming skills, - how to be in a motivated mindset, - the power of knowledge of your codebase, how to acquire it and make every person in your team acquire it too, - how to find the source of a bug quickly in a large and unfamiliar codebase, - where to focus your refactoring efforts so that they make your life easier, - and many more things to be efficient and happy when working with legacy code!

This book constitutes the refereed proceedings of the 4th Conference on Extreme Programming and Agile Methods, XP/Agile Universe 2004, held in Calgary, Canada in August 2004. The 18 revised full papers presented together with summaries of workshops, panels, and tutorials were carefully reviewed and selected from 45 submissions. The papers are organized in topical sections on testing and integration, managing requirements and usability, pair programming, foundations of agility, process adaptation, and educational issues.

How to Reduce Code Complexity and Develop Software More Sustainably "Mark Seemann is well known for explaining complex concepts clearly and thoroughly. In this book he condenses his wide-ranging software development experience into a set of practical, pragmatic techniques for writing sustainable and human-friendly code. This book will be a must-read for every programmer." -- Scott Wlaschin, author of Domain Modeling Made Functional Code That Fits in Your Head offers indispensable, practical advice for writing code at a sustainable pace and controlling the complexity that causes projects to spin out of control. Reflecting decades of experience helping software teams succeed, Mark Seemann guides you from zero (no code) to deployed features and shows how to maintain a good cruising speed as you add functionality, address cross-cutting concerns, troubleshoot, and optimize. You'll find valuable ideas, practices, and processes for key issues ranging from checklists to teamwork, encapsulation to decomposition, API design to unit testing. Seemann illuminates his insights with code examples drawn from a complete sample project. Written in C#, they're designed to be clear and useful to anyone who uses any object-oriented language including Java , C++, and Python. To facilitate deeper exploration, all code and extensive commit messages are available for download. Choose mindsets and processes that work, and escape bad metaphors that don't Use checklists to liberate yourself, improving outcomes with the skills you already have Get past “analysis paralysis” by creating and deploying a vertical slice of your application Counteract forces that lead to code rot and unnecessary complexity Master better techniques for changing code behavior Discover ways to solve code problems more quickly and effectively Think more productively about performance and security If you've ever suffered through bad projects or had to cope with unmaintainable legacy code, this guide will help you make things better next time and every time. Register your book for convenient access to downloads, updates, and/or corrections as they become available. See inside book for details.

How to Write Code You're Proud of . . . Every Single Day ". . . [A] timely and humble reminder of the ever-increasing complexity of our programmatic world and how we owe it to the legacy of humankind--and to ourselves--to practice ethical development. Take your time reading Clean Craftsmanship. . . . Keep this book on your go-to bookshelf. Let this book be your old friend--your Uncle Bob, your guide--as you make your way through this world with curiosity and courage." --From the Foreword by Stacia Heimgartner Viscardi, CST & Agile Mentor In Clean Craftsmanship, the legendary Robert C. Martin ("Uncle Bob") has written the principles that define the profession--and the craft--of software development. Uncle Bob brings together the disciplines, standards, and ethics you need to deliver robust, effective code and to be proud of all the software you write. Robert Martin, the best-selling author of Clean Code, provides a pragmatic, technical, and prescriptive guide to the foundational disciplines of software craftsmanship. He discusses standards, showing how the world's expectations of developers often differ from their own and helping you bring the two in sync. Bob concludes with the ethics of the programming profession, describing the fundamental promises all developers should make to their colleagues, their users, and, above all, themselves. With Uncle Bob's insights, all programmers and their managers can consistently deliver code that builds trust instead of undermining it--trust among users and throughout societies that depend on software for their survival. Moving towards the "north star" of true software craftsmanship: the state of knowing how to program well Practical, specific guidance for applying five core disciplines: test-driven development, refactoring, simple design, collaborative programming, and acceptance tests How developers and teams can promote productivity, quality, and courage The true meaning of integrity and teamwork among programmers, and ten specific commitments every software professional should make Register your book for convenient access to the book's companion videos, updates, and/or corrections as they become available. See inside book for details.