A layout that supports structured logging should probably be the default

[atheriel]

One of the key advantages of this package is its support for structured logging, but that isn't surfaced by default, and it probably should be.

The default output for Go's slog package looks like a good compromise here; it isn't pure logfmt because it wants to be backward-compatible with the older log API:

2022/11/08 15:28:26 INFO hello count=3