Structured Logging in Go with slog
Plain text logs are easy to print but difficult to query reliably. Once an application runs across multiple processes or containers, operators usually need to filter events by fields such as HTTP status, request path, customer ID, or latency rather than search arbitrary strings.
Go’s standard library includes log/slog for structured logging. It was added in Go 1.21, so the examples in this article require Go 1.21 or newer.
What structured logging changes A traditional log message often embeds data inside prose:
