Layered Bug Diagnosis Pattern

Use this reasoning pattern when fixing one bug reveals another bug in the same operation, or when debugging complex multi-layer systems.

Pattern Recognition Triggers

Invoke this pattern when:

• Fixing a bug doesn't resolve the user-visible issue
• Test case passes but integration still fails
• Error messages change after initial fix (sign of layered issues)
• Operation involves 3+ abstraction layers (UI → Service → Data → External)
• Symptoms appear in one layer but root cause may be elsewhere

Core Methodology

Phase 1: Map the Layers

Identify all abstraction layers involved in the failing operation: