WECODE
Debugging
2023-10-26

Works on My Machine, Fails in Production

Analyze why code behaves differently across environments and fix the real root cause.

SCENARIO

Act as a senior software engineer with over 20 years of production experience.

CONTEXT:

The following code works locally but fails in another environment (staging or production). Assume this is an engineering failure, not bad luck.

YOUR TASK:

  • Walk through the code execution step by step
  • Identify environment-specific behavior, hidden dependencies, and incorrect assumptions
  • Call out fragile logic, poor error handling, reliance on local state, filesystem quirks, timing assumptions, and dependency differences

ANALYSIS REQUIREMENTS:

  • Provide a clear root-cause analysis supported by evidence from the code or execution flow
  • Explain what logs, signals, or checks would confirm the diagnosis before applying a fix

SOLUTION EXPECTATIONS:

  • Propose a robust, production-grade solution, not a band-aid
  • Refactor or redesign any part that would not survive real-world production conditions
  • Improve observability, error reporting, and defensive checks

VALIDATION:

  • Explain how the fix can be validated
  • Describe how it prevents similar failures in the future

INPUT:

Code: [Insert Code] Failure context: [Local works / Production fails details]

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Act as a senior software engineer with over 20 years of production experience.

CONTEXT: The following code executes without throwing errors but produces incorrect, inconsistent, or unexpected results. The failure is silent, making it difficult to detect and debug.

YOUR TASK:

  • Walk through the code execution step by step
  • Identify where logic, data flow, or assumptions break down without triggering errors
  • Detect hidden side effects, implicit type conversions, state corruption, or incorrect edge-case handling

ANALYSIS REQUIREMENTS:

  • Explain why the code appears to work while still producing wrong results
  • Pinpoint the exact conditions under which the incorrect behavior occurs
  • Call out weak validations, missing invariants, or misleading defaults

SOLUTION EXPECTATIONS:

  • Provide a clear root-cause analysis, not speculation
  • Propose a robust fix that makes failures explicit rather than silent
  • Improve data validation, assertions, and defensive programming

VALIDATION:

  • Explain how to verify the fix with tests, checks, or instrumentation
  • Describe how to prevent similar silent failures in the future

INPUT: Code: [Insert Code] Observed behavior: [Expected vs actual output]