Golang Error Handling

A comprehensive guide to production-grade error handling in Go that enforces the "handle once" rule: log or return, never both. It covers the full stack from sentinel errors and custom types to wrapping with %w, inspection with errors.Is/As, and structured logging with slog. The standout bit is the emphasis on low-cardinality error messages,keeping variable data out of error strings and into structured attributes so your APM tools can actually group errors instead of exploding into thousands of unique entries. Includes samber/oops for rich production errors with stack traces and context, plus parallel audit modes for reviewing large codebases. If you've ever debugged a mess of duplicate logs or ungroupable Sentry errors, this will resonate.