Thinking Guides

Purpose: Expand your thinking to catch things you might not have considered.

Why Thinking Guides?

Most bugs and tech debt come from "didn't think of that", not from lack of skill:

Didn't think about what happens at layer boundaries → cross-layer bugs
Didn't think about code patterns repeating → duplicated code everywhere
Didn't think about edge cases → runtime errors
Didn't think about future maintainers → unreadable code

These guides help you ask the right questions before coding.

Available Guides

Guide	Purpose	When to Use
Code Reuse Thinking Guide	Identify patterns and reduce duplication	When you notice repeated patterns
Cross-Layer Thinking Guide	Think through data flow across layers	Features spanning multiple layers

Quick Reference: Thinking Triggers

When to Think About Cross-Layer Issues

Feature touches 3+ layers (API, Service, Component, Database)
Data format changes between layers
Multiple consumers need the same data
You're not sure where to put some logic

→ Read Cross-Layer Thinking Guide

When to Think About Code Reuse

You're writing similar code to something that exists
You see the same pattern repeated 3+ times
You're adding a new field to multiple places
You're modifying any constant or config
You're creating a new utility/helper function ← Search first!

→ Read Code Reuse Thinking Guide

Pre-Modification Rule (CRITICAL)

Before changing ANY value, ALWAYS search first!

# Search for the value you're about to change
grep -r "value_to_change" .

This single habit prevents most "forgot to update X" bugs.

How to Use This Directory

Before coding: Skim the relevant thinking guide
During coding: If something feels repetitive or complex, check the guides
After bugs: Add new insights to the relevant guide (learn from mistakes)

Contributing

Found a new "didn't think of that" moment? Add it to the relevant guide.

Core Principle: 30 minutes of thinking saves 3 hours of debugging.