Logs were designed for humans grepping text files at 2am. Now they also have to feed query engines, correlation and anomaly detection. Here's what that changes about what you write, and which field names to use.

Three patterns that look like structured logging but aren't, in C#, Java, Go and Python, and what to write instead.

A log line that says 'payment failed' tells you something broke. One that says 'payment failed, enterprise customer, checkout-v2 experiment' tells you what to do about it. Here's how to add that context to every log event in a .NET service, safely, with Serilog.

The same logging mistakes turn up in every team and every stack: inconsistent field names, values buried in message strings, missing trace context, personal data and secrets in error logs, and loops that log the same thing ten thousand times. Here is where to look and what to fix.

Enrichment turns isolated log records into connected business events. Here is the architecture that makes it work — static resource attributes, background-refreshed caches, and per-request scopes — without taxing the request path.

Logs carry operational state at a resolution metrics can't match. Most teams only open them after something breaks. This guide covers how to query them continuously, turn them into metrics, and alert on what they surface without blowing up cardinality or cost.