Logging Best Practices

This gives you production-ready logging patterns with Winston for JavaScript, including structured JSON formatting, request correlation IDs via AsyncLocalStorage, and PII sanitization helpers. You get a clear log level guide, async context propagation across requests, and practical examples for redacting sensitive fields like emails and credit cards. Also points you to Python structlog and Go zap implementations if you're working across languages. The "never do" section alone is worth it: no console.log in production, no passwords in logs, no debug-level spam. If you've ever dealt with log bloat or accidentally shipped customer data to your logging service, this covers the basics to prevent it.