speedbump.go
func NewLimiter(
	client *redis.Client,
	hasher RateHasher,
	max int64,
) *RateLimiter {
	return &RateLimiter{
		redisClient: client,
		hasher:      hasher,
		max:         max,
	}
}
func NewLimiter(
	client *redis.Client,
	hasher RateHasher,
	max int64,
) *RateLimiter {
	return &RateLimiter{
		redisClient: client,
		hasher:      hasher,
		max:         max,
	}
}
// NewLimiter creates a new instance of a rate limiter.