Building Systems Like a Senior Engineer
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.
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
- Chapter 1: Aces High — Developing the Habits of a Senior Engineer
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