MonixRateLimiter.scala

class MonixRateLimiter(queue: MVar[RateLimiterMsg], queueFiber: Fiber[Task, Unit]) {
  def runLimited[T](f: Task[T]): Task[T] = {
    for {
      mv <- MVar.empty[T]
      _ <- queue.put(Schedule(f.flatMap(mv.put)))
      r <- mv.take
    } yield r
  }
}

object MonixRateLimiter extends StrictLogging {
  def create(maxRuns: Int, per: FiniteDuration): Task[MonixRateLimiter] =
    for {
      queue <- MVar.empty[RateLimiterMsg]
      runQueueFiber <- 
        runQueue(RateLimiterQueue[Task[Unit]](maxRuns, per.toMillis), queue)
          .fork
    } yield new MonixRateLimiter(queue, runQueueFiber)
}