Debugging and Error Recovery
Overview
Systematic debugging with structured triage. When something breaks, stop adding features, preserve evidence, and follow a structured process to find and fix the root cause. Guessing wastes time. The triage checklist works for test failures, build errors, runtime bugs, and production incidents.
When to Use
- Tests fail after a code change
- The build breaks
- Runtime behavior doesn't match expectations
- A bug report arrives
- An error appears in logs or console
- Something worked before and stopped working
The Stop-the-Line Rule
When anything unexpected happens:
1. STOP adding features or making changes
2. PRESERVE evidence (error output, logs, repro steps)
3. DIAGNOSE using the triage checklist
4. FIX the root cause
5. GUARD against recurrence
6. RESUME only after verification passes
Don't push past a failing test or broken build to work on the next feature. Errors compound. A bug in Step 3 that goes unfixed makes Steps 4-6 wrong.
The Triage Checklist
Work through these steps in order. Do not skip steps.
Step 1: Reproduce
Make the failure happen reliably. If you can't reproduce it, you can't fix it wit…