Why dict[str, Any] Slowly Destroys Your Code
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In this video, I refactor a Python booking system from loose dictionaries into a strict domain model using dataclasses, enums, and value objects. I show where stronger types improve maintainability, and where a simple string is still the right choice.
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🔖 Chapters:
0:00 Intro
0:30 The Working Before Version
1:42 The Core Design Lesson
2:55 Step 1: Replace the Dictionary
6:04 Step 2: Split Out Domain Concepts
8:38 Step 3: Replace Magic Strings
10:18 Step 4: Add a Money Value Object
13:46 Step 5: Move Rules Near the Concept
15:19 Step 6: Clean Up the Business Function
15:36 Step 7: Validate at the Boundary
17:52 Keep One String on Purpose
19:04 Why This Improves Maintainability
19:44 The *kwargs Design Smell
20:20 Final Thoughts
#arjancodes #softwaredesign #python
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