chapter one

1 What is performance engineering?

 

This chapter covers

  • What is performance engineering and why does it matter?
  • The performance decay cycle that traps most teams
  • Employing the Fast by Default model to bake in performance improvements at every stage in development
  • Keeping software fast over time by measuring against user-centered goals, building for speed, owning performance as a team, and maintaining high standards

Performance engineering is the practice of designing and running software so that fast and reliable behavior is the default outcome, rather than a lucky accident. It is not a single framework or tool, but rather the way you choose architectures, write code, design user flows, set budgets, test, and monitor in production so that speed and stability are built in from the start. Where traditional performance work treats “make it faster” as a rescue mission late in the project, performance engineering treats it as a first-class requirement that shapes decisions across web, backend, mobile, and desktop systems.

1.1 The performance decay cycle

1.2 Why we need performance engineering

1.2.1 Web and mobile: Small delays, large losses

1.2.2 Backend systems: Latency prevents adoption

1.2.3 Desktop and native apps: Performance drives retention

1.3 The Fast by Default model

1.3.1 System Paths across platforms

1.3.2 Practices to protect performance

1.4 Example of the Fast by Default model

1.5 How to use this book

1.6 Summary