principle-fix-root-causes

# Fix Root Causes When debugging, do not paper over symptoms. Trace every problem to its root cause and fix it there. **Why:** Symptom fixes accumulate. Each workaround makes the system harder to reason about, and the real bug remains. Root-cause fixes are slower upfront but reduce total debugging time. **Pattern:** - Reproduce first (if you can't reproduce it, you can't verify your fix) - Ask "why" until you hit the root cause - Resist the urge to add guards (adding a nil check to silence a crash is a symptom fix) - If a workaround needs a paragraph-long comment to justify it, the code is wrong (fix the code, not the comment) - Check for the pattern, not just the instance (grep for the same pattern, fix all instances) - When stuck, instrument. Don't guess (add logging, read the actual error) **Restart bugs: suspect state before code** Code doesn't change between runs. State does. When something "fails after restart," suspect stale persistent state first: config files, caches, lock files, serialized state. If clearing a state file restores behavior, prioritize state validation as the fix.