Looks to be the case based on the config. I'm suprised storage wasn't abstracted to accommodate redis or the like which is essential in a load balanced scenario

Looks to be the case based on the config. I'm suprised storage wasn't abstracted to accommodate redis or the like which is essential in a load balanced scenario. The API doesn't seem quite idiomatic either, I'd expect to create a struct containing options and a function that closes over the http.Handler interface e.g. func(l *Limiter) Limit(next http.Handler) http.Handler or a function that takes options and a next http.Handler that creates a struct implementing http.Handler.