code: func LoggerMiddleware(rw ResponseWriter, req *Request, next NextMiddlewareFunc) {
  	startTime := time.Now()
  
  	next(rw, req)
  
  	duration := time.Since(startTime).Nanoseconds()
  	var durationUnits string
  	switch {
  	case duration > 2000000:
  		durationUnits = "ms"
  		duration /= 1000000
  	case duration > 1000:
  		durationUnits = "μs"
  		duration /= 1000
  	default:
  		durationUnits = "ns"
  	}
  
  	Logger.Printf("[%d %s] %d '%s'\n", duration, durationUnits, rw.StatusCode(), req.URL.Path)
  }
docs: // LoggerMiddleware is generic middleware that will log requests to Logger (by default, Stdout).