Systematic Debugging

Use this skill to investigate, isolate, and remediate defects using 4-Phase Systematic Root Cause Analysis (RCA) and empirical Verification-Before-Completion gates.

When to Use

• diagnosing defects, flakiness, or test failures across microservices, background workers, or UI components
• unexpected runtime exceptions, data corruption, state desynchronization, or memory leaks occur
• tempted to apply speculative quick fixes or trial-and-error edits without empirical proof
• establishing a minimal deterministic reproduction test before touching production code
• verifying fixes with rigorous verification-before-completion gates to eliminate false-green sign-offs
• investigating complex distributed failures involving eventual consistency, race conditions, or timing windows
• isolating state transition errors in stateful workflows, distributed sagas, or payment lifecycles
• resolving non-deterministic flakiness in async message queues, outbox patterns, or cache invalidation
• auditing intermittent test failures in CI/CD pipelines before escalating or skipping checks

Core Rules