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5. Test-Driven Development (TDD)

I use Test-Driven Development (TDD) to build systems that are reliable, testable, and safe to change.

🧠 Test-Driven Development (TDD)

I use Test-Driven Development (TDD) to build systems that are reliable, testable, and safe to change.


🎯 How I Think About It

TDD is a development approach where I:

1. write a test for expected behavior

1. implement the code to pass the test

1. refactor while keeping tests passing

👉 This ensures that code is driven by requirements and expected outcomes, not assumptions


🧩 How I Apply TDD

Start with Behavior

I define what the system should do before writing implementation
focus on expected inputs and outputs

👉 keeps logic aligned with requirements


Small Iterations

write small tests
implement minimal code to pass
repeat

👉 reduces complexity and risk


Refactoring with Confidence

once tests pass, I improve code structure
tests ensure behavior remains correct

👉 enables safe refactoring


🧠 Benefits I Focus On

early detection of bugs
clearer understanding of requirements
safer changes and refactoring
better-designed, loosely coupled code

⚖️ Tradeoff Awareness

TDD can:

slow down initial development
require discipline and good test design

But it helps:

reduce debugging time later
improve long-term maintainability

📌 Practical Approach

I don’t force TDD everywhere.

I use it especially for:

complex business logic
critical workflows
areas that change frequently

💬 Summary

My approach to TDD focuses on:

building correct behavior first
ensuring confidence in changes
maintaining long-term code quality

This helps deliver systems that are stable, testable, and easy to evolve.