| name | debugging--root-cause-analysis |
| description | The art of identifying the root cause of software defects through heuristic analysis and logical deduction. |
Debugging & Root Cause Analysis
The art of identifying the root cause of software defects through heuristic analysis and logical deduction.
Knowledge
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The Taxonomy of Bugs
* **Logic Errors:** The code does what you told it to do, but not what you intended (e.g., Off-by-one).
* **Heisenbugs:** Bugs that disappear or alter behavior when you try to study them (often race conditions or uninitialized memory).
* **Configuration Drift:** The code is fine; the environment (Env vars, paths, dependencies) is wrong.
* **Swallowed Exceptions:** The silent killers. `try: ... except: pass` blocks that hide the smoking gun.
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Investigation Techniques
* **Binary Search:** Isolating the failure by halving the search space (commenting out code, checking git bisect).
* **Rubber Ducking:** Explaining the logic line-by-line to find the flaw in the mental model.
* **Log Analysis:** Looking for the *absence* of expected events, not just the presence of errors.
* **Boundary Analysis:** Checking edges (0, -1, empty lists, maxint).
Abilities
- Tracing data flow through complex, nested logic without running the code.
- Identifying potential race conditions in async/threaded code.
- Correlating vague user symptoms ('it feels slow', 'sometimes it crashes') to specific code blocks.
- Distinguishing between a Symptom (what the user sees) and the Root Cause (the actual defect).
- Hypothesis Generation: Formulating 'If X is broken, then Y should happen' scenarios.
