Systematic debugging frameworks for finding and fixing bugs - includes root cause analysis, defense-in-depth validation, and verification protocols

Debugging Skills A collection of systematic debugging methodologies that ensure thorough investigation before attempting fixes. Available Sub Skills Systematic Debugging Location: systematic debugging/SKILL.md Four phase debugging framework: Root Cause Investigation → Pattern Analysis → Hypothesis Testing → Implementation. The iron law: NO FIXES WITHOUT ROOT CAUSE INVESTIGATION FIRST. Root Cause Tracing Location: root cause tracing/SKILL.md Trace bugs backward through the call stack to find the original trigger. Don't fix symptoms find where invalid data originated and fix at the source. Defense in Depth Validation Location: defense in depth/SKILL.md Validate at every layer data passes through to make bugs structurally impossible. Four layers: Entry Point → Business Logic → Environment Guards → Debug Instrumentation. Verification Before Completion Location: verification before completion/SKILL.md Run verification commands and confirm output before claiming success. The iron law: NO COMPLETION CLAIMS WITHOUT FRESH VERIFICATION EVIDENCE. When to Use Bug in production → Start with systematic debugging Error deep in stack trace → Use root cause tracing Fixing a bug → Apply defense in depth after finding root cause About to claim "done" → Use verification before completion Quick Dispatch Symptom Sub Skill Test failure, unexpected behavior systematic debugging Error appears in wrong location root cause tracing Same bug keeps recurring defense in depth Need to confirm fix works verification before completion Core Philosophy "Systematic debugging is FASTER than guess and check thrashing." From real debugging sessions: Systematic approach: 15 30 minutes to fix Random fixes approach: 2 3 hours of thrashing First time fix rate: 95% vs 40%