Structured Logging System Design

Core Principles

• Logs are data — Treat every log as a queryable, structured data point
• Single source of truth — One logging configuration, used everywhere
• Context is king — Every log must be traceable to its source and request
• Human + Machine readable — Structured for parsing, clear for debugging
• Progressive enhancement — Start simple, add fields as needed
• No secrets — Never log passwords, tokens, or PII without masking

System Architecture

The Golden Rule

Configure once, use everywhere. Never instantiate loggers directly in business code.

Architecture Overview