In middleware.go I see:

slog.Float64(s.ResponseDuration, float64(duration.Milliseconds())),

But the ECS reference says:

event.duration: Duration of the event in nanoseconds.

The OTEL reference says:

Unit: s

And the GCP reference says:

A duration in seconds with up to nine fractional digits, ending with 's'.

So is the ECS output off by a factor one million, and OTEL and GCP off by a factor one thousand, or am I missing something?