func main() {
    r := &asynq.RedisClientOpt{
        Addr: "localhost:6379",
    }

    client := asynq.NewClient(r)

    // Create a task with task type and payload
    t1 := asynq.NewTask("send_welcome_email", map[string]interface{}{"user_id": 42})

    t2 := asynq.NewTask("send_reminder_email", map[string]interface{}{"user_id": 42})

    // Process immediately
    err := client.Schedule(t1, time.Now())

    // Process 24 hrs later
    err = client.Schedule(t2, time.Now().Add(24 * time.Hour))

    // If processing fails, retry up to 10 times (Default is 25)
    err = client.Schedule(t1, time.Now(), asynq.Retry(10))

    // Use custom queue called "critical"
    err = client.Schedule(t1, time.Now(), asynq.Queue("critical"))
}

func main() {
    r := &asynq.RedisClientOpt{
        Addr: "localhost:6379",
    }

    bg := asynq.NewBackground(r, &asynq.Config{
        // Specify how many concurrent workers to use
        Concurrency: 10,
        // You can optionally create multiple queues
        // with different priority level
        Queues: map[string]uint{
            "critical": 6,
            "default":  3,
            "low":      1,
        },
        // See the godoc for other configuration options
    })

    bg.Run(handler)
}

// ProcessTask should return nil if the processing of a task
// is successful.
//
// If ProcessTask return a non-nil error or panics, the task
// will be retried after delay.
type Handler interface {
    ProcessTask(*Task) error
}