Building Systems Like a Senior Engineer
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Building Systems Like a Senior Engineer

About the Book

Build Like a Senior Engineer — One Card at a Time

You know how to code. Now learn how to design.

In Building Systems Like a Senior Engineer, you’ll build a fully extensible card game engine — and along the way, you’ll learn the habits, tradeoffs, and architectural thinking that set senior developers apart.

This isn’t just another coding book. It’s a hands-on, opinionated walkthrough of:

  • Clean, test-first design
  • Domain modeling and encapsulation
  • Real-world backend structure (without the boilerplate)
  • Game engines that teach system design

Whether you’re an early-career dev looking to level up, or a mid-level engineer hungry to understand how senior engineers think, this book will teach you how to build smarter — and teach through your code.

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  • Categories

    • Software Engineering
    • Python
    • DevOps
    • Refactoring
    • Testing
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About the Author

Aaron Smith
Aaron Smith

Aaron Smith is a software engineer who specializes in backend systems and clean architectural design. He started his career writing APIs and event-driven services, and over time discovered a passion for helping developers grow — not just in skill, but in judgment.

Aaron believes that senior engineering is less about titles and more about how you think, how you build, and how you teach. His writing is practical, hands-on, and grounded in the kinds of decisions engineers face every day — from modeling systems to designing for change.

When he’s not coding or writing, he’s probably working on something quietly ambitious, like reverse-engineering card games or turning real-world system challenges into learning tools.

Table of Contents

    • Chapter 1: Aces High — Developing the Habits of a Senior Engineer
      • Who This Book Is For
      • What This Book Covers
      • What This Book Doesn’t Cover
      • How to Read This Book
      • Let’s Play
    • Chapter 2: Cards and Decks
      • Starting With a Failing Test
      • Making the Test Pass
      • Adding __repr__ for Debugging
      • Refactoring with Enums
      • Giving Cards a Value
      • Writing Tests for Card Values
      • Implementing the value Property
      • Wrapping Up Chapter 2
    • Chapter 3: Dealing with the Deck
      • Starting with a Failing Test
      • Making the Test Pass
      • Verifying Suit Composition
      • Refactoring with Fixtures
      • Designing Deck Behaviors
      • Random Shuffle vs Human Shuffle
      • Dealing Cards
      • Making the Deal Test Pass
      • Handling Edge Cases in Dealing
      • Refactoring to an Abstract Base Class (ABC)
      • Initializing and Resetting the Deck
      • Wrapping Up Chapter 3
    • Chapter 4: Continuous Integration & Delivery
      • Automated Code Formatting
      • Automated Linting with Ruff
      • Running Tests in CI
      • Publishing to PyPI with workflow_dispatch
      • Wrapping Up Chapter 4
    • Chapter 5: Modeling a Poker Hand
      • Introducing Hand-Based Games
      • Defining the Player Class
      • Accepting a Hand of Cards
      • Retroactively Testing the 5-Card Rule
      • Wrapping Up Chapter 5
    • Chapter 6: Evaluating Hands and Determining a Winner
      • High Card
      • Sets
      • Straights, Flushes, and the Case for a Combined Scorer
      • Encapsulating Context: The Ace Problem and the Value of a Wrapper
      • Wrapping Up Chapter 6

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