v0.14.0

Minor doc fixes
Export DefaultRetryDelayFunc
2025-09-17 20:30:06 +08:00 · 2021-01-14 06:49:36 -08:00 · 2021-01-14 06:43:44 -08:00 · 2021-01-14 06:43:44 -08:00 · 2021-01-14 06:43:44 -08:00 · 2021-01-14 06:43:44 -08:00
73 changed files with 10418 additions and 4344 deletions
--- a/.travis.yml
+++ b/.travis.yml
@@ -2,12 +2,12 @@ language: go
 go_import_path: github.com/hibiken/asynq
 git:
  depth: 1
-go: [1.13.x, 1.14.x]
+go: [1.13.x, 1.14.x, 1.15.x]
 script:
  - go test -race -v -coverprofile=coverage.txt -covermode=atomic ./...
-  - go test -run=XXX -bench=. -loglevel=debug ./...
+  - go test -run=^$ -bench=. -loglevel=debug ./...
 services:
  - redis-server
 after_success:
-  - bash ./.travis/benchcmp.sh
+  - travis_wait 60 bash ./.travis/benchstat.sh
  - bash <(curl -s https://codecov.io/bash)
--- a/.travis/benchstat.sh
+++ b/.travis/benchstat.sh
@@ -2,17 +2,19 @@ if [ "${TRAVIS_PULL_REQUEST_BRANCH:-$TRAVIS_BRANCH}" != "master" ]; then
    REMOTE_URL="$(git config --get remote.origin.url)";
    cd ${TRAVIS_BUILD_DIR}/.. && \
    git clone ${REMOTE_URL} "${TRAVIS_REPO_SLUG}-bench" && \
+    # turn the detached message off
+    git config --global advice.detachedHead false && \
    cd "${TRAVIS_REPO_SLUG}-bench" && \

    # Benchmark master
    git checkout master && \
-    go test -run=XXX -bench=. ./... > master.txt && \
+    go test -run=^$ -bench=. -count=5 -timeout=60m -benchmem ./... > master.txt && \

    # Benchmark feature branch
    git checkout ${TRAVIS_COMMIT} && \
-    go test -run=XXX -bench=. ./... > feature.txt && \
+    go test -run=^$ -bench=. -count=5 -timeout=60m -benchmem ./... > feature.txt && \

    # compare two benchmarks
-    go get -u golang.org/x/tools/cmd/benchcmp && \
-    benchcmp master.txt feature.txt;
+    go get -u golang.org/x/perf/cmd/benchstat && \
+    benchstat master.txt feature.txt;
 fi
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,13 +7,135 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0

 ## [Unreleased]

+## [0.14.0] - 2021-01-14
+
+**IMPORTATNT**: Please run `asynq migrate` command to migrate from the previous versions.
+
+### Changed
+
+- Renamed `DeadTask` to `ArchivedTask`.
+- Renamed the operation `Kill` to `Archive` in `Inpsector`.
+- Print stack trace when Handler panics.
+- Include a file name and a line number in the error message when recovering from a panic.
+
+### Added
+
+- `DefaultRetryDelayFunc` is now a public API, which can be used in the custom `RetryDelayFunc`.
+- `SkipRetry` error is added to be used as a return value from `Handler`.
+- `Servers` method is added to `Inspector`
+- `CancelActiveTask` method is added to `Inspector`.
+- `ListSchedulerEnqueueEvents` method is added to `Inspector`.
+- `SchedulerEntries` method is added to `Inspector`.
+- `DeleteQueue` method is added to `Inspector`.
+
+## [0.13.1] - 2020-11-22
+
+### Fixed
+
+- Fixed processor to wait for specified time duration before forcefully shutdown workers.
+
+## [0.13.0] - 2020-10-13
+
+### Added
+
+- `Scheduler` type is added to enable periodic tasks. See the godoc for its APIs and [wiki](https://github.com/hibiken/asynq/wiki/Periodic-Tasks) for the getting-started guide.
+
+### Changed
+
+- interface `Option` has changed. See the godoc for the new interface.
+  This change would have no impact as long as you are using exported functions (e.g. `MaxRetry`, `Queue`, etc)
+  to create `Option`s.
+
+### Added
+
+- `Payload.String() string` method is added
+- `Payload.MarshalJSON() ([]byte, error)` method is added
+
+## [0.12.0] - 2020-09-12
+
+**IMPORTANT**: If you are upgrading from a previous version, please install the latest version of the CLI `go get -u github.com/hibiken/asynq/tools/asynq` and run `asynq migrate` command. No process should be writing to Redis while you run the migration command.
+
+## The semantics of queue have changed
+
+Previously, we called tasks that are ready to be processed _"Enqueued tasks"_, and other tasks that are scheduled to be processed in the future _"Scheduled tasks"_, etc.
+We changed the semantics of _"Enqueue"_ slightly; All tasks that client pushes to Redis are _Enqueued_ to a queue. Within a queue, tasks will transition from one state to another.
+Possible task states are:
+
+- `Pending`: task is ready to be processed (previously called "Enqueued")
+- `Active`: tasks is currently being processed (previously called "InProgress")
+- `Scheduled`: task is scheduled to be processed in the future
+- `Retry`: task failed to be processed and will be retried again in the future
+- `Dead`: task has exhausted all of its retries and stored for manual inspection purpose
+
+**These semantics change is reflected in the new `Inspector` API and CLI commands.**
+
+---
+
+### Changed
+
+#### `Client`
+
+Use `ProcessIn` or `ProcessAt` option to schedule a task instead of `EnqueueIn` or `EnqueueAt`.
+
+| Previously                  | v0.12.0                                    |
+| --------------------------- | ------------------------------------------ |
+| `client.EnqueueAt(t, task)` | `client.Enqueue(task, asynq.ProcessAt(t))` |
+| `client.EnqueueIn(d, task)` | `client.Enqueue(task, asynq.ProcessIn(d))` |
+
+#### `Inspector`
+
+All Inspector methods are scoped to a queue, and the methods take `qname (string)` as the first argument.  
+`EnqueuedTask` is renamed to `PendingTask` and its corresponding methods.  
+`InProgressTask` is renamed to `ActiveTask` and its corresponding methods.  
+Command "Enqueue" is replaced by the verb "Run" (e.g. `EnqueueAllScheduledTasks` --> `RunAllScheduledTasks`)
+
+#### `CLI`
+
+CLI commands are restructured to use subcommands. Commands are organized into a few management commands:
+To view details on any command, use `asynq help <command> <subcommand>`.
+
+- `asynq stats`
+- `asynq queue [ls inspect history rm pause unpause]`
+- `asynq task [ls cancel delete kill run delete-all kill-all run-all]`
+- `asynq server [ls]`
+
+### Added
+
+#### `RedisConnOpt`
+
+- `RedisClusterClientOpt` is added to connect to Redis Cluster.
+- `Username` field is added to all `RedisConnOpt` types in order to authenticate connection when Redis ACLs are used.
+
+#### `Client`
+
+- `ProcessIn(d time.Duration) Option` and `ProcessAt(t time.Time) Option` are added to replace `EnqueueIn` and `EnqueueAt` functionality.
+
+#### `Inspector`
+
+- `Queues() ([]string, error)` method is added to get all queue names.
+- `ClusterKeySlot(qname string) (int64, error)` method is added to get queue's hash slot in Redis cluster.
+- `ClusterNodes(qname string) ([]ClusterNode, error)` method is added to get a list of Redis cluster nodes for the given queue.
+- `Close() error` method is added to close connection with redis.
+
+### `Handler`
+
+- `GetQueueName(ctx context.Context) (string, bool)` helper is added to extract queue name from a context.
+
+## [0.11.0] - 2020-07-28
+
+### Added
+
+- `Inspector` type was added to monitor and mutate state of queues and tasks.
+- `HealthCheckFunc` and `HealthCheckInterval` fields were added to `Config` to allow user to specify a callback
+  function to check for broker connection.
+
 ## [0.10.0] - 2020-07-06

 ### Changed

 - All tasks now requires timeout or deadline. By default, timeout is set to 30 mins.
 - Tasks that exceed its deadline are automatically retried.
- Encoding schema for task message has changed. Please install the latest CLI and run `migrate` command if 
+- Encoding schema for task message has changed. Please install the latest CLI and run `migrate` command if
  you have tasks enqueued with the previous version of asynq.
 - API of `(*Client).Enqueue`, `(*Client).EnqueueIn`, and `(*Client).EnqueueAt` has changed to return a `*Result`.
 - API of `ErrorHandler` has changed. It now takes context as the first argument and removed `retried`, `maxRetry` from the argument list.
@@ -31,7 +153,6 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0

 - Fixes the JSON number overflow issue (https://github.com/hibiken/asynq/issues/166).

-
 ## [0.9.2] - 2020-06-08

 ### Added
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -45,6 +45,7 @@ Thank you! We'll try to respond as quickly as possible.
 6. Create a new pull request

 Please try to keep your pull request focused in scope and avoid including unrelated commits.
+Please run tests against redis cluster locally with `--redis_cluster` flag to ensure that code works for Redis cluster. TODO: Run tests using Redis cluster on CI.

 After you have submitted your pull request, we'll try to get back to you as soon as possible. We may suggest some changes or improvements.

--- a/README.md
+++ b/README.md
@@ -1,15 +1,14 @@
 # Asynq

 [![Build Status](https://travis-ci.com/hibiken/asynq.svg?token=paqzfpSkF4p23s5Ux39b&branch=master)](https://travis-ci.com/hibiken/asynq)
-[![License: MIT](https://img.shields.io/badge/license-MIT-green.svg)](https://opensource.org/licenses/MIT)
-[![Go Report Card](https://goreportcard.com/badge/github.com/hibiken/asynq)](https://goreportcard.com/report/github.com/hibiken/asynq)
 [![GoDoc](https://godoc.org/github.com/hibiken/asynq?status.svg)](https://godoc.org/github.com/hibiken/asynq)
+[![Go Report Card](https://goreportcard.com/badge/github.com/hibiken/asynq)](https://goreportcard.com/report/github.com/hibiken/asynq)
+[![License: MIT](https://img.shields.io/badge/license-MIT-green.svg)](https://opensource.org/licenses/MIT)
 [![Gitter chat](https://badges.gitter.im/go-asynq/gitter.svg)](https://gitter.im/go-asynq/community)
-[![codecov](https://codecov.io/gh/hibiken/asynq/branch/master/graph/badge.svg)](https://codecov.io/gh/hibiken/asynq)

 ## Overview

-Asynq is a Go library for queueing tasks and processing them in the background with workers. It is backed by Redis and it is designed to have a low barrier to entry. It should be integrated in your web stack easily.
+Asynq is a Go library for queueing tasks and processing them asynchronously with workers. It's backed by Redis and is designed to be scalable yet easy to get started.

 Highlevel overview of how Asynq works:

@@ -42,7 +41,9 @@ A system can consist of multiple worker servers and brokers, giving way to high
 - Allow [timeout and deadline per task](https://github.com/hibiken/asynq/wiki/Task-Timeout-and-Cancelation)
 - [Flexible handler interface with support for middlewares](https://github.com/hibiken/asynq/wiki/Handler-Deep-Dive)
 - [Ability to pause queue](/tools/asynq/README.md#pause) to stop processing tasks from the queue
- [Support Redis Sentinels](https://github.com/hibiken/asynq/wiki/Automatic-Failover) for HA
+- [Periodic Tasks](https://github.com/hibiken/asynq/wiki/Periodic-Tasks)
+- [Support Redis Cluster](https://github.com/hibiken/asynq/wiki/Redis-Cluster) for automatic sharding and high availability
+- [Support Redis Sentinels](https://github.com/hibiken/asynq/wiki/Automatic-Failover) for high availability
 - [CLI](#command-line-tool) to inspect and remote-control queues and tasks

 ## Quickstart
@@ -66,8 +67,8 @@ import (

 // A list of task types.
 const (
-    EmailDelivery   = "email:deliver"
-    ImageProcessing = "image:process"
+    TypeEmailDelivery   = "email:deliver"
+    TypeImageResize     = "image:resize"
 )

 //----------------------------------------------
@@ -77,19 +78,19 @@ const (

 func NewEmailDeliveryTask(userID int, tmplID string) *asynq.Task {
    payload := map[string]interface{}{"user_id": userID, "template_id": tmplID}
-    return asynq.NewTask(EmailDelivery, payload)
+    return asynq.NewTask(TypeEmailDelivery, payload)
 }

-func NewImageProcessingTask(src, dst string) *asynq.Task {
-    payload := map[string]interface{}{"src": src, "dst": dst}
-    return asynq.NewTask(ImageProcessing, payload)
+func NewImageResizeTask(src string) *asynq.Task {
+    payload := map[string]interface{}{"src": src}
+    return asynq.NewTask(TypeImageResize, payload)
 }

 //---------------------------------------------------------------
 // Write a function HandleXXXTask to handle the input task.
 // Note that it satisfies the asynq.HandlerFunc interface.
-// 
-// Handler doesn't need to be a function. You can define a type 
+//
+// Handler doesn't need to be a function. You can define a type
 // that satisfies asynq.Handler interface. See examples below.
 //---------------------------------------------------------------

@@ -103,12 +104,12 @@ func HandleEmailDeliveryTask(ctx context.Context, t *asynq.Task) error {
        return err
    }
    fmt.Printf("Send Email to User: user_id = %d, template_id = %s\n", userID, tmplID)
-    // Email delivery logic ...
+    // Email delivery code ...
    return nil
 }

 // ImageProcessor implements asynq.Handler interface.
-type ImageProcesser struct {
+type ImageProcessor struct {
    // ... fields for struct
 }

@@ -117,12 +118,8 @@ func (p *ImageProcessor) ProcessTask(ctx context.Context, t *asynq.Task) error {
    if err != nil {
        return err
    }
-    dst, err := t.Payload.GetString("dst")
-    if err != nil {
-        return err
-    }
-    fmt.Printf("Process image: src = %s, dst = %s\n", src, dst)
-    // Image processing logic ...
+    fmt.Printf("Resize image: src = %s\n", src)
+    // Image resizing code ...
    return nil
 }

@@ -131,14 +128,14 @@ func NewImageProcessor() *ImageProcessor {
 }
 ```

-In your web application code, import the above package and use [`Client`](https://pkg.go.dev/github.com/hibiken/asynq?tab=doc#Client) to put tasks on the queue.  
-A task will be processed asynchronously by a background worker as soon as the task gets enqueued.  
-Scheduled tasks will be stored in Redis and will be enqueued at the specified time.
+In your application code, import the above package and use [`Client`](https://pkg.go.dev/github.com/hibiken/asynq?tab=doc#Client) to put tasks on the queue.

 ```go
 package main

 import (
+    "fmt"
+    "log"
    "time"

    "github.com/hibiken/asynq"
@@ -167,11 +164,11 @@ func main() {

    // ------------------------------------------------------------
    // Example 2: Schedule task to be processed in the future.
-    //            Use (*Client).EnqueueIn or (*Client).EnqueueAt.
+    //            Use ProcessIn or ProcessAt option.
    // ------------------------------------------------------------

    t = tasks.NewEmailDeliveryTask(42, "other:template:id")
-    res, err = c.EnqueueIn(24*time.Hour, t)
+    res, err = c.Enqueue(t, asynq.ProcessIn(24*time.Hour))
    if err != nil {
        log.Fatal("could not schedule task: %v", err)
    }
@@ -179,13 +176,13 @@ func main() {


    // ----------------------------------------------------------------------------
-    // Example 3: Set options to tune task processing behavior.
+    // Example 3: Set other options to tune task processing behavior.
    //            Options include MaxRetry, Queue, Timeout, Deadline, Unique etc.
    // ----------------------------------------------------------------------------

-    c.SetDefaultOptions(tasks.ImageProcessing, asynq.MaxRetry(10), asynq.Timeout(time.Minute))
+    c.SetDefaultOptions(tasks.TypeImageResize, asynq.MaxRetry(10), asynq.Timeout(3*time.Minute))

-    t = tasks.NewImageProcessingTask("some/blobstore/url", "other/blobstore/url")
+    t = tasks.NewImageResizeTask("some/blobstore/path")
    res, err = c.Enqueue(t)
    if err != nil {
        log.Fatal("could not enqueue task: %v", err)
@@ -197,7 +194,7 @@ func main() {
    //            Options passed at enqueue time override default ones, if any.
    // ---------------------------------------------------------------------------

-    t = tasks.NewImageProcessingTask("some/blobstore/url", "other/blobstore/url")
+    t = tasks.NewImageResizeTask("some/blobstore/path")
    res, err = c.Enqueue(t, asynq.Queue("critical"), asynq.Timeout(30*time.Second))
    if err != nil {
        log.Fatal("could not enqueue task: %v", err)
@@ -206,7 +203,7 @@ func main() {
 }
 ```

-Next, create a worker server to process these tasks in the background.  
+Next, start a worker server to process these tasks in the background.  
 To start the background workers, use [`Server`](https://pkg.go.dev/github.com/hibiken/asynq?tab=doc#Server) and provide your [`Handler`](https://pkg.go.dev/github.com/hibiken/asynq?tab=doc#Handler) to process the tasks.

 You can optionally use [`ServeMux`](https://pkg.go.dev/github.com/hibiken/asynq?tab=doc#ServeMux) to create a handler, just as you would with [`"net/http"`](https://golang.org/pkg/net/http/) Handler.
@@ -240,8 +237,8 @@ func main() {

    // mux maps a type to a handler
    mux := asynq.NewServeMux()
-    mux.HandleFunc(tasks.EmailDelivery, tasks.HandleEmailDeliveryTask)
-    mux.Handle(tasks.ImageProcessing, tasks.NewImageProcessor())
+    mux.HandleFunc(tasks.TypeEmailDelivery, tasks.HandleEmailDeliveryTask)
+    mux.Handle(tasks.TypeImageResize, tasks.NewImageProcessor())
    // ...register other handlers...

    if err := srv.Run(mux); err != nil {
@@ -282,7 +279,7 @@ go get -u github.com/hibiken/asynq/tools/asynq

 | Dependency                 | Version |
 | -------------------------- | ------- |
-| [Redis](https://redis.io/) | v2.8+   |
+| [Redis](https://redis.io/) | v3.0+   |
 | [Go](https://golang.org/)  | v1.13+  |

 ## Contributing
--- a/asynq.go
+++ b/asynq.go
@@ -37,7 +37,9 @@ func NewTask(typename string, payload map[string]interface{}) *Task {
 //
 // RedisConnOpt represents a sum of following types:
 //
-// RedisClientOpt | *RedisClientOpt | RedisFailoverClientOpt | *RedisFailoverClientOpt
+//   - RedisClientOpt
+//   - RedisFailoverClientOpt
+//   - RedisClusterClientOpt
 type RedisConnOpt interface{}

 // RedisClientOpt is used to create a redis client that connects
@@ -50,7 +52,12 @@ type RedisClientOpt struct {
 	// Redis server address in "host:port" format.
 	Addr string

-	// Redis server password.
+	// Username to authenticate the current connection when Redis ACLs are used.
+	// See: https://redis.io/commands/auth.
+	Username string
+
+	// Password to authenticate the current connection.
+	// See: https://redis.io/commands/auth.
 	Password string

 	// Redis DB to select after connecting to a server.
@@ -81,7 +88,12 @@ type RedisFailoverClientOpt struct {
 	// Redis sentinel password.
 	SentinelPassword string

-	// Redis server password.
+	// Username to authenticate the current connection when Redis ACLs are used.
+	// See: https://redis.io/commands/auth.
+	Username string
+
+	// Password to authenticate the current connection.
+	// See: https://redis.io/commands/auth.
 	Password string

 	// Redis DB to select after connecting to a server.
@@ -97,6 +109,30 @@ type RedisFailoverClientOpt struct {
 	TLSConfig *tls.Config
 }

+// RedisFailoverClientOpt is used to creates a redis client that connects to
+// redis cluster.
+type RedisClusterClientOpt struct {
+	// A seed list of host:port addresses of cluster nodes.
+	Addrs []string
+
+	// The maximum number of retries before giving up.
+	// Command is retried on network errors and MOVED/ASK redirects.
+	// Default is 8 retries.
+	MaxRedirects int
+
+	// Username to authenticate the current connection when Redis ACLs are used.
+	// See: https://redis.io/commands/auth.
+	Username string
+
+	// Password to authenticate the current connection.
+	// See: https://redis.io/commands/auth.
+	Password string
+
+	// TLS Config used to connect to a server.
+	// TLS will be negotiated only if this field is set.
+	TLSConfig *tls.Config
+}
+
 // ParseRedisURI parses redis uri string and returns RedisConnOpt if uri is valid.
 // It returns a non-nil error if uri cannot be parsed.
 //
@@ -173,12 +209,13 @@ func parseRedisSentinelURI(u *url.URL) (RedisConnOpt, error) {
 // createRedisClient returns a redis client given a redis connection configuration.
 //
 // Passing an unexpected type as a RedisConnOpt argument will cause panic.
-func createRedisClient(r RedisConnOpt) *redis.Client {
+func createRedisClient(r RedisConnOpt) redis.UniversalClient {
 	switch r := r.(type) {
 	case *RedisClientOpt:
 		return redis.NewClient(&redis.Options{
 			Network:   r.Network,
 			Addr:      r.Addr,
+			Username:  r.Username,
 			Password:  r.Password,
 			DB:        r.DB,
 			PoolSize:  r.PoolSize,
@@ -188,6 +225,7 @@ func createRedisClient(r RedisConnOpt) *redis.Client {
 		return redis.NewClient(&redis.Options{
 			Network:   r.Network,
 			Addr:      r.Addr,
+			Username:  r.Username,
 			Password:  r.Password,
 			DB:        r.DB,
 			PoolSize:  r.PoolSize,
@@ -198,6 +236,7 @@ func createRedisClient(r RedisConnOpt) *redis.Client {
 			MasterName:       r.MasterName,
 			SentinelAddrs:    r.SentinelAddrs,
 			SentinelPassword: r.SentinelPassword,
+			Username:         r.Username,
 			Password:         r.Password,
 			DB:               r.DB,
 			PoolSize:         r.PoolSize,
@@ -208,11 +247,28 @@ func createRedisClient(r RedisConnOpt) *redis.Client {
 			MasterName:       r.MasterName,
 			SentinelAddrs:    r.SentinelAddrs,
 			SentinelPassword: r.SentinelPassword,
+			Username:         r.Username,
 			Password:         r.Password,
 			DB:               r.DB,
 			PoolSize:         r.PoolSize,
 			TLSConfig:        r.TLSConfig,
 		})
+	case RedisClusterClientOpt:
+		return redis.NewClusterClient(&redis.ClusterOptions{
+			Addrs:        r.Addrs,
+			MaxRedirects: r.MaxRedirects,
+			Username:     r.Username,
+			Password:     r.Password,
+			TLSConfig:    r.TLSConfig,
+		})
+	case *RedisClusterClientOpt:
+		return redis.NewClusterClient(&redis.ClusterOptions{
+			Addrs:        r.Addrs,
+			MaxRedirects: r.MaxRedirects,
+			Username:     r.Username,
+			Password:     r.Password,
+			TLSConfig:    r.TLSConfig,
+		})
 	default:
 		panic(fmt.Sprintf("asynq: unexpected type %T for RedisConnOpt", r))
 	}
--- a/asynq_test.go
+++ b/asynq_test.go
@@ -7,6 +7,7 @@ package asynq
 import (
 	"flag"
 	"sort"
+	"strings"
 	"testing"

 	"github.com/go-redis/redis/v7"
@@ -24,6 +25,9 @@ var (
 	redisAddr string
 	redisDB   int

+	useRedisCluster   bool
+	redisClusterAddrs string // comma-separated list of host:port
+
 	testLogLevel = FatalLevel
 )

@@ -32,23 +36,52 @@ var testLogger *log.Logger
 func init() {
 	flag.StringVar(&redisAddr, "redis_addr", "localhost:6379", "redis address to use in testing")
 	flag.IntVar(&redisDB, "redis_db", 14, "redis db number to use in testing")
+	flag.BoolVar(&useRedisCluster, "redis_cluster", false, "use redis cluster as a broker in testing")
+	flag.StringVar(&redisClusterAddrs, "redis_cluster_addrs", "localhost:7000,localhost:7001,localhost:7002", "comma separated list of redis server addresses")
 	flag.Var(&testLogLevel, "loglevel", "log level to use in testing")

 	testLogger = log.NewLogger(nil)
 	testLogger.SetLevel(toInternalLogLevel(testLogLevel))
 }

-func setup(tb testing.TB) *redis.Client {
+func setup(tb testing.TB) (r redis.UniversalClient) {
 	tb.Helper()
-	r := redis.NewClient(&redis.Options{
-		Addr: redisAddr,
-		DB:   redisDB,
-	})
+	if useRedisCluster {
+		addrs := strings.Split(redisClusterAddrs, ",")
+		if len(addrs) == 0 {
+			tb.Fatal("No redis cluster addresses provided. Please set addresses using --redis_cluster_addrs flag.")
+		}
+		r = redis.NewClusterClient(&redis.ClusterOptions{
+			Addrs: addrs,
+		})
+	} else {
+		r = redis.NewClient(&redis.Options{
+			Addr: redisAddr,
+			DB:   redisDB,
+		})
+	}
 	// Start each test with a clean slate.
 	h.FlushDB(tb, r)
 	return r
 }

+func getRedisConnOpt(tb testing.TB) RedisConnOpt {
+	tb.Helper()
+	if useRedisCluster {
+		addrs := strings.Split(redisClusterAddrs, ",")
+		if len(addrs) == 0 {
+			tb.Fatal("No redis cluster addresses provided. Please set addresses using --redis_cluster_addrs flag.")
+		}
+		return RedisClusterClientOpt{
+			Addrs: addrs,
+		}
+	}
+	return RedisClientOpt{
+		Addr: redisAddr,
+		DB:   redisDB,
+	}
+}
+
 var sortTaskOpt = cmp.Transformer("SortMsg", func(in []*Task) []*Task {
 	out := append([]*Task(nil), in...) // Copy input to avoid mutating it
 	sort.Slice(out, func(i, j int) bool {
--- a/benchmark_test.go
+++ b/benchmark_test.go
@@ -18,10 +18,7 @@ func BenchmarkEndToEndSimple(b *testing.B) {
 	for n := 0; n < b.N; n++ {
 		b.StopTimer() // begin setup
 		setup(b)
-		redis := &RedisClientOpt{
-			Addr: redisAddr,
-			DB:   redisDB,
-		}
+		redis := getRedisConnOpt(b)
 		client := NewClient(redis)
 		srv := NewServer(redis, Config{
 			Concurrency: 10,
@@ -37,6 +34,7 @@ func BenchmarkEndToEndSimple(b *testing.B) {
 				b.Fatalf("could not enqueue a task: %v", err)
 			}
 		}
+		client.Close()

 		var wg sync.WaitGroup
 		wg.Add(count)
@@ -61,10 +59,7 @@ func BenchmarkEndToEnd(b *testing.B) {
 	for n := 0; n < b.N; n++ {
 		b.StopTimer() // begin setup
 		setup(b)
-		redis := &RedisClientOpt{
-			Addr: redisAddr,
-			DB:   redisDB,
-		}
+		redis := getRedisConnOpt(b)
 		client := NewClient(redis)
 		srv := NewServer(redis, Config{
 			Concurrency: 10,
@@ -82,10 +77,11 @@ func BenchmarkEndToEnd(b *testing.B) {
 		}
 		for i := 0; i < count; i++ {
 			t := NewTask(fmt.Sprintf("scheduled%d", i), map[string]interface{}{"data": i})
-			if _, err := client.EnqueueAt(time.Now().Add(time.Second), t); err != nil {
+			if _, err := client.Enqueue(t, ProcessIn(1*time.Second)); err != nil {
 				b.Fatalf("could not enqueue a task: %v", err)
 			}
 		}
+		client.Close()

 		var wg sync.WaitGroup
 		wg.Add(count * 2)
@@ -127,10 +123,7 @@ func BenchmarkEndToEndMultipleQueues(b *testing.B) {
 	for n := 0; n < b.N; n++ {
 		b.StopTimer() // begin setup
 		setup(b)
-		redis := &RedisClientOpt{
-			Addr: redisAddr,
-			DB:   redisDB,
-		}
+		redis := getRedisConnOpt(b)
 		client := NewClient(redis)
 		srv := NewServer(redis, Config{
 			Concurrency: 10,
@@ -160,6 +153,7 @@ func BenchmarkEndToEndMultipleQueues(b *testing.B) {
 				b.Fatalf("could not enqueue a task: %v", err)
 			}
 		}
+		client.Close()

 		var wg sync.WaitGroup
 		wg.Add(highCount + defaultCount + lowCount)
@@ -185,10 +179,7 @@ func BenchmarkClientWhileServerRunning(b *testing.B) {
 	for n := 0; n < b.N; n++ {
 		b.StopTimer() // begin setup
 		setup(b)
-		redis := &RedisClientOpt{
-			Addr: redisAddr,
-			DB:   redisDB,
-		}
+		redis := getRedisConnOpt(b)
 		client := NewClient(redis)
 		srv := NewServer(redis, Config{
 			Concurrency: 10,
@@ -207,7 +198,7 @@ func BenchmarkClientWhileServerRunning(b *testing.B) {
 		// Schedule 10,000 tasks.
 		for i := 0; i < count; i++ {
 			t := NewTask(fmt.Sprintf("scheduled%d", i), map[string]interface{}{"data": i})
-			if _, err := client.EnqueueAt(time.Now().Add(time.Second), t); err != nil {
+			if _, err := client.Enqueue(t, ProcessIn(1*time.Second)); err != nil {
 				b.Fatalf("could not enqueue a task: %v", err)
 			}
 		}
@@ -233,6 +224,7 @@ func BenchmarkClientWhileServerRunning(b *testing.B) {

 		b.StopTimer() // begin teardown
 		srv.Stop()
+		client.Close()
 		b.StartTimer() // end teardown
 	}
 }
--- a/client.go
+++ b/client.go
@@ -7,7 +7,7 @@ package asynq
 import (
 	"errors"
 	"fmt"
-	"sort"
+	"strconv"
 	"strings"
 	"sync"
 	"time"
@@ -29,7 +29,7 @@ type Client struct {
 	rdb  *rdb.RDB
 }

-// NewClient and returns a new Client given a redis connection option.
+// NewClient returns a new Client instance given a redis connection option.
 func NewClient(r RedisConnOpt) *Client {
 	rdb := rdb.NewRDB(createRedisClient(r))
 	return &Client{
@@ -38,16 +38,39 @@ func NewClient(r RedisConnOpt) *Client {
 	}
 }

+type OptionType int
+
+const (
+	MaxRetryOpt OptionType = iota
+	QueueOpt
+	TimeoutOpt
+	DeadlineOpt
+	UniqueOpt
+	ProcessAtOpt
+	ProcessInOpt
+)
+
 // Option specifies the task processing behavior.
-type Option interface{}
+type Option interface {
+	// String returns a string representation of the option.
+	String() string
+
+	// Type describes the type of the option.
+	Type() OptionType
+
+	// Value returns a value used to create this option.
+	Value() interface{}
+}

 // Internal option representations.
 type (
-	retryOption    int
-	queueOption    string
-	timeoutOption  time.Duration
-	deadlineOption time.Time
-	uniqueOption   time.Duration
+	retryOption     int
+	queueOption     string
+	timeoutOption   time.Duration
+	deadlineOption  time.Time
+	uniqueOption    time.Duration
+	processAtOption time.Time
+	processInOption time.Duration
 )

 // MaxRetry returns an option to specify the max number of times
@@ -61,13 +84,21 @@ func MaxRetry(n int) Option {
 	return retryOption(n)
 }

+func (n retryOption) String() string     { return fmt.Sprintf("MaxRetry(%d)", int(n)) }
+func (n retryOption) Type() OptionType   { return MaxRetryOpt }
+func (n retryOption) Value() interface{} { return int(n) }
+
 // Queue returns an option to specify the queue to enqueue the task into.
 //
 // Queue name is case-insensitive and the lowercased version is used.
-func Queue(name string) Option {
-	return queueOption(strings.ToLower(name))
+func Queue(qname string) Option {
+	return queueOption(strings.ToLower(qname))
 }

+func (qname queueOption) String() string     { return fmt.Sprintf("Queue(%q)", string(qname)) }
+func (qname queueOption) Type() OptionType   { return QueueOpt }
+func (qname queueOption) Value() interface{} { return string(qname) }
+
 // Timeout returns an option to specify how long a task may run.
 // If the timeout elapses before the Handler returns, then the task
 // will be retried.
@@ -80,6 +111,10 @@ func Timeout(d time.Duration) Option {
 	return timeoutOption(d)
 }

+func (d timeoutOption) String() string     { return fmt.Sprintf("Timeout(%v)", time.Duration(d)) }
+func (d timeoutOption) Type() OptionType   { return TimeoutOpt }
+func (d timeoutOption) Value() interface{} { return time.Duration(d) }
+
 // Deadline returns an option to specify the deadline for the given task.
 // If it reaches the deadline before the Handler returns, then the task
 // will be retried.
@@ -90,6 +125,12 @@ func Deadline(t time.Time) Option {
 	return deadlineOption(t)
 }

+func (t deadlineOption) String() string {
+	return fmt.Sprintf("Deadline(%v)", time.Time(t).Format(time.UnixDate))
+}
+func (t deadlineOption) Type() OptionType   { return DeadlineOpt }
+func (t deadlineOption) Value() interface{} { return time.Time(t) }
+
 // Unique returns an option to enqueue a task only if the given task is unique.
 // Task enqueued with this option is guaranteed to be unique within the given ttl.
 // Once the task gets processed successfully or once the TTL has expired, another task with the same uniqueness may be enqueued.
@@ -103,6 +144,102 @@ func Unique(ttl time.Duration) Option {
 	return uniqueOption(ttl)
 }

+func (ttl uniqueOption) String() string     { return fmt.Sprintf("Unique(%v)", time.Duration(ttl)) }
+func (ttl uniqueOption) Type() OptionType   { return UniqueOpt }
+func (ttl uniqueOption) Value() interface{} { return time.Duration(ttl) }
+
+// ProcessAt returns an option to specify when to process the given task.
+//
+// If there's a conflicting ProcessIn option, the last option passed to Enqueue overrides the others.
+func ProcessAt(t time.Time) Option {
+	return processAtOption(t)
+}
+
+func (t processAtOption) String() string {
+	return fmt.Sprintf("ProcessAt(%v)", time.Time(t).Format(time.UnixDate))
+}
+func (t processAtOption) Type() OptionType   { return ProcessAtOpt }
+func (t processAtOption) Value() interface{} { return time.Time(t) }
+
+// ProcessIn returns an option to specify when to process the given task relative to the current time.
+//
+// If there's a conflicting ProcessAt option, the last option passed to Enqueue overrides the others.
+func ProcessIn(d time.Duration) Option {
+	return processInOption(d)
+}
+
+func (d processInOption) String() string     { return fmt.Sprintf("ProcessIn(%v)", time.Duration(d)) }
+func (d processInOption) Type() OptionType   { return ProcessInOpt }
+func (d processInOption) Value() interface{} { return time.Duration(d) }
+
+// parseOption interprets a string s as an Option and returns the Option if parsing is successful,
+// otherwise returns non-nil error.
+func parseOption(s string) (Option, error) {
+	fn, arg := parseOptionFunc(s), parseOptionArg(s)
+	switch fn {
+	case "Queue":
+		qname, err := strconv.Unquote(arg)
+		if err != nil {
+			return nil, err
+		}
+		return Queue(qname), nil
+	case "MaxRetry":
+		n, err := strconv.Atoi(arg)
+		if err != nil {
+			return nil, err
+		}
+		return MaxRetry(n), nil
+	case "Timeout":
+		d, err := time.ParseDuration(arg)
+		if err != nil {
+			return nil, err
+		}
+		return Timeout(d), nil
+	case "Deadline":
+		t, err := time.Parse(time.UnixDate, arg)
+		if err != nil {
+			return nil, err
+		}
+		return Deadline(t), nil
+	case "Unique":
+		d, err := time.ParseDuration(arg)
+		if err != nil {
+			return nil, err
+		}
+		return Unique(d), nil
+	case "ProcessAt":
+		t, err := time.Parse(time.UnixDate, arg)
+		if err != nil {
+			return nil, err
+		}
+		return ProcessAt(t), nil
+	case "ProcessIn":
+		d, err := time.ParseDuration(arg)
+		if err != nil {
+			return nil, err
+		}
+		return ProcessIn(d), nil
+	default:
+		return nil, fmt.Errorf("cannot not parse option string %q", s)
+	}
+}
+
+func parseOptionFunc(s string) string {
+	i := strings.Index(s, "(")
+	return s[:i]
+}
+
+func parseOptionArg(s string) string {
+	i := strings.Index(s, "(")
+	if i >= 0 {
+		j := strings.Index(s, ")")
+		if j > i {
+			return s[i+1 : j]
+		}
+	}
+	return ""
+}
+
 // ErrDuplicateTask indicates that the given task could not be enqueued since it's a duplicate of another task.
 //
 // ErrDuplicateTask error only applies to tasks enqueued with a Unique option.
@@ -114,65 +251,53 @@ type option struct {
 	timeout   time.Duration
 	deadline  time.Time
 	uniqueTTL time.Duration
+	processAt time.Time
 }

-func composeOptions(opts ...Option) option {
+// composeOptions merges user provided options into the default options
+// and returns the composed option.
+// It also validates the user provided options and returns an error if any of
+// the user provided options fail the validations.
+func composeOptions(opts ...Option) (option, error) {
 	res := option{
-		retry:    defaultMaxRetry,
-		queue:    base.DefaultQueueName,
-		timeout:  0, // do not set to deafultTimeout here
-		deadline: time.Time{},
+		retry:     defaultMaxRetry,
+		queue:     base.DefaultQueueName,
+		timeout:   0, // do not set to deafultTimeout here
+		deadline:  time.Time{},
+		processAt: time.Now(),
 	}
 	for _, opt := range opts {
 		switch opt := opt.(type) {
 		case retryOption:
 			res.retry = int(opt)
 		case queueOption:
-			res.queue = string(opt)
+			trimmed := strings.TrimSpace(string(opt))
+			if err := validateQueueName(trimmed); err != nil {
+				return option{}, err
+			}
+			res.queue = trimmed
 		case timeoutOption:
 			res.timeout = time.Duration(opt)
 		case deadlineOption:
 			res.deadline = time.Time(opt)
 		case uniqueOption:
 			res.uniqueTTL = time.Duration(opt)
+		case processAtOption:
+			res.processAt = time.Time(opt)
+		case processInOption:
+			res.processAt = time.Now().Add(time.Duration(opt))
 		default:
 			// ignore unexpected option
 		}
 	}
-	return res
+	return res, nil
 }

-// uniqueKey computes the redis key used for the given task.
-// It returns an empty string if ttl is zero.
-func uniqueKey(t *Task, ttl time.Duration, qname string) string {
-	if ttl == 0 {
-		return ""
+func validateQueueName(qname string) error {
+	if len(qname) == 0 {
+		return fmt.Errorf("queue name must contain one or more characters")
 	}
-	return fmt.Sprintf("%s:%s:%s", t.Type, serializePayload(t.Payload.data), qname)
-}
-
-func serializePayload(payload map[string]interface{}) string {
-	if payload == nil {
-		return "nil"
-	}
-	type entry struct {
-		k string
-		v interface{}
-	}
-	var es []entry
-	for k, v := range payload {
-		es = append(es, entry{k, v})
-	}
-	// sort entries by key
-	sort.Slice(es, func(i, j int) bool { return es[i].k < es[j].k })
-	var b strings.Builder
-	for _, e := range es {
-		if b.Len() > 0 {
-			b.WriteString(",")
-		}
-		b.WriteString(fmt.Sprintf("%s=%v", e.k, e.v))
-	}
-	return b.String()
+	return nil
 }

 const (
@@ -205,6 +330,12 @@ type Result struct {
 	// ID is a unique identifier for the task.
 	ID string

+	// EnqueuedAt is the time the task was enqueued in UTC.
+	EnqueuedAt time.Time
+
+	// ProcessAt indicates when the task should be processed.
+	ProcessAt time.Time
+
 	// Retry is the maximum number of retry for the task.
 	Retry int

@@ -229,51 +360,29 @@ type Result struct {
 	Deadline time.Time
 }

-// EnqueueAt schedules task to be enqueued at the specified time.
-//
-// EnqueueAt returns nil if the task is scheduled successfully, otherwise returns a non-nil error.
-//
-// The argument opts specifies the behavior of task processing.
-// If there are conflicting Option values the last one overrides others.
-// By deafult, max retry is set to 25 and timeout is set to 30 minutes.
-func (c *Client) EnqueueAt(t time.Time, task *Task, opts ...Option) (*Result, error) {
-	return c.enqueueAt(t, task, opts...)
+// Close closes the connection with redis.
+func (c *Client) Close() error {
+	return c.rdb.Close()
 }

-// Enqueue enqueues task to be processed immediately.
+// Enqueue enqueues the given task to be processed asynchronously.
 //
 // Enqueue returns nil if the task is enqueued successfully, otherwise returns a non-nil error.
 //
 // The argument opts specifies the behavior of task processing.
 // If there are conflicting Option values the last one overrides others.
 // By deafult, max retry is set to 25 and timeout is set to 30 minutes.
+// If no ProcessAt or ProcessIn options are passed, the task will be processed immediately.
 func (c *Client) Enqueue(task *Task, opts ...Option) (*Result, error) {
-	return c.enqueueAt(time.Now(), task, opts...)
-}
-
-// EnqueueIn schedules task to be enqueued after the specified delay.
-//
-// EnqueueIn returns nil if the task is scheduled successfully, otherwise returns a non-nil error.
-//
-// The argument opts specifies the behavior of task processing.
-// If there are conflicting Option values the last one overrides others.
-// By deafult, max retry is set to 25 and timeout is set to 30 minutes.
-func (c *Client) EnqueueIn(d time.Duration, task *Task, opts ...Option) (*Result, error) {
-	return c.enqueueAt(time.Now().Add(d), task, opts...)
-}
-
-// Close closes the connection with redis server.
-func (c *Client) Close() error {
-	return c.rdb.Close()
-}
-
-func (c *Client) enqueueAt(t time.Time, task *Task, opts ...Option) (*Result, error) {
 	c.mu.Lock()
-	defer c.mu.Unlock()
 	if defaults, ok := c.opts[task.Type]; ok {
 		opts = append(defaults, opts...)
 	}
-	opt := composeOptions(opts...)
+	c.mu.Unlock()
+	opt, err := composeOptions(opts...)
+	if err != nil {
+		return nil, err
+	}
 	deadline := noDeadline
 	if !opt.deadline.IsZero() {
 		deadline = opt.deadline
@@ -286,6 +395,10 @@ func (c *Client) enqueueAt(t time.Time, task *Task, opts ...Option) (*Result, er
 		// If neither deadline nor timeout are set, use default timeout.
 		timeout = defaultTimeout
 	}
+	var uniqueKey string
+	if opt.uniqueTTL > 0 {
+		uniqueKey = base.UniqueKey(opt.queue, task.Type, task.Payload.data)
+	}
 	msg := &base.TaskMessage{
 		ID:        uuid.New(),
 		Type:      task.Type,
@@ -294,14 +407,14 @@ func (c *Client) enqueueAt(t time.Time, task *Task, opts ...Option) (*Result, er
 		Retry:     opt.retry,
 		Deadline:  deadline.Unix(),
 		Timeout:   int64(timeout.Seconds()),
-		UniqueKey: uniqueKey(task, opt.uniqueTTL, opt.queue),
+		UniqueKey: uniqueKey,
 	}
-	var err error
 	now := time.Now()
-	if t.Before(now) || t.Equal(now) {
+	if opt.processAt.Before(now) || opt.processAt.Equal(now) {
+		opt.processAt = now
 		err = c.enqueue(msg, opt.uniqueTTL)
 	} else {
-		err = c.schedule(msg, t, opt.uniqueTTL)
+		err = c.schedule(msg, opt.processAt, opt.uniqueTTL)
 	}
 	switch {
 	case err == rdb.ErrDuplicateTask:
@@ -310,11 +423,13 @@ func (c *Client) enqueueAt(t time.Time, task *Task, opts ...Option) (*Result, er
 		return nil, err
 	}
 	return &Result{
-		ID:       msg.ID.String(),
-		Queue:    msg.Queue,
-		Retry:    msg.Retry,
-		Timeout:  timeout,
-		Deadline: deadline,
+		ID:         msg.ID.String(),
+		EnqueuedAt: time.Now().UTC(),
+		ProcessAt:  opt.processAt,
+		Queue:      msg.Queue,
+		Retry:      msg.Retry,
+		Timeout:    timeout,
+		Deadline:   deadline,
 	}, nil
 }

--- a/client_test.go
+++ b/client_test.go
@@ -15,12 +15,10 @@ import (
 	"github.com/hibiken/asynq/internal/base"
 )

-func TestClientEnqueueAt(t *testing.T) {
+func TestClientEnqueueWithProcessAtOption(t *testing.T) {
 	r := setup(t)
-	client := NewClient(RedisClientOpt{
-		Addr: redisAddr,
-		DB:   redisDB,
-	})
+	client := NewClient(getRedisConnOpt(t))
+	defer client.Close()

 	task := NewTask("send_email", map[string]interface{}{"to": "customer@gmail.com", "from": "merchant@example.com"})

@@ -32,11 +30,11 @@ func TestClientEnqueueAt(t *testing.T) {
 	tests := []struct {
 		desc          string
 		task          *Task
-		processAt     time.Time
-		opts          []Option
+		processAt     time.Time // value for ProcessAt option
+		opts          []Option  // other options
 		wantRes       *Result
-		wantEnqueued  map[string][]*base.TaskMessage
-		wantScheduled []h.ZSetEntry
+		wantPending   map[string][]*base.TaskMessage
+		wantScheduled map[string][]base.Z
 	}{
 		{
 			desc:      "Process task immediately",
@@ -44,12 +42,14 @@ func TestClientEnqueueAt(t *testing.T) {
 			processAt: now,
 			opts:      []Option{},
 			wantRes: &Result{
-				Queue:    "default",
-				Retry:    defaultMaxRetry,
-				Timeout:  defaultTimeout,
-				Deadline: noDeadline,
+				EnqueuedAt: now.UTC(),
+				ProcessAt:  now,
+				Queue:      "default",
+				Retry:      defaultMaxRetry,
+				Timeout:    defaultTimeout,
+				Deadline:   noDeadline,
 			},
-			wantEnqueued: map[string][]*base.TaskMessage{
+			wantPending: map[string][]*base.TaskMessage{
 				"default": {
 					{
 						Type:     task.Type,
@@ -61,7 +61,9 @@ func TestClientEnqueueAt(t *testing.T) {
 					},
 				},
 			},
-			wantScheduled: nil, // db is flushed in setup so zset does not exist hence nil
+			wantScheduled: map[string][]base.Z{
+				"default": {},
+			},
 		},
 		{
 			desc:      "Schedule task to be processed in the future",
@@ -69,23 +71,29 @@ func TestClientEnqueueAt(t *testing.T) {
 			processAt: oneHourLater,
 			opts:      []Option{},
 			wantRes: &Result{
-				Queue:    "default",
-				Retry:    defaultMaxRetry,
-				Timeout:  defaultTimeout,
-				Deadline: noDeadline,
+				EnqueuedAt: now.UTC(),
+				ProcessAt:  oneHourLater,
+				Queue:      "default",
+				Retry:      defaultMaxRetry,
+				Timeout:    defaultTimeout,
+				Deadline:   noDeadline,
 			},
-			wantEnqueued: nil, // db is flushed in setup so list does not exist hence nil
-			wantScheduled: []h.ZSetEntry{
-				{
-					Msg: &base.TaskMessage{
-						Type:     task.Type,
-						Payload:  task.Payload.data,
-						Retry:    defaultMaxRetry,
-						Queue:    "default",
-						Timeout:  int64(defaultTimeout.Seconds()),
-						Deadline: noDeadline.Unix(),
+			wantPending: map[string][]*base.TaskMessage{
+				"default": {},
+			},
+			wantScheduled: map[string][]base.Z{
+				"default": {
+					{
+						Message: &base.TaskMessage{
+							Type:     task.Type,
+							Payload:  task.Payload.data,
+							Retry:    defaultMaxRetry,
+							Queue:    "default",
+							Timeout:  int64(defaultTimeout.Seconds()),
+							Deadline: noDeadline.Unix(),
+						},
+						Score: oneHourLater.Unix(),
 					},
-					Score: float64(oneHourLater.Unix()),
 				},
 			},
 		},
@@ -94,45 +102,50 @@ func TestClientEnqueueAt(t *testing.T) {
 	for _, tc := range tests {
 		h.FlushDB(t, r) // clean up db before each test case.

-		gotRes, err := client.EnqueueAt(tc.processAt, tc.task, tc.opts...)
+		opts := append(tc.opts, ProcessAt(tc.processAt))
+		gotRes, err := client.Enqueue(tc.task, opts...)
 		if err != nil {
 			t.Error(err)
 			continue
 		}
-		if diff := cmp.Diff(tc.wantRes, gotRes, cmpopts.IgnoreFields(Result{}, "ID")); diff != "" {
-			t.Errorf("%s;\nEnqueueAt(processAt, task) returned %v, want %v; (-want,+got)\n%s",
-				tc.desc, gotRes, tc.wantRes, diff)
+		cmpOptions := []cmp.Option{
+			cmpopts.IgnoreFields(Result{}, "ID"),
+			cmpopts.EquateApproxTime(500 * time.Millisecond),
+		}
+		if diff := cmp.Diff(tc.wantRes, gotRes, cmpOptions...); diff != "" {
+			t.Errorf("%s;\nEnqueue(task, ProcessAt(%v)) returned %v, want %v; (-want,+got)\n%s",
+				tc.desc, tc.processAt, gotRes, tc.wantRes, diff)
 		}

-		for qname, want := range tc.wantEnqueued {
-			gotEnqueued := h.GetEnqueuedMessages(t, r, qname)
-			if diff := cmp.Diff(want, gotEnqueued, h.IgnoreIDOpt); diff != "" {
+		for qname, want := range tc.wantPending {
+			gotPending := h.GetPendingMessages(t, r, qname)
+			if diff := cmp.Diff(want, gotPending, h.IgnoreIDOpt, cmpopts.EquateEmpty()); diff != "" {
 				t.Errorf("%s;\nmismatch found in %q; (-want,+got)\n%s", tc.desc, base.QueueKey(qname), diff)
 			}
 		}
-
-		gotScheduled := h.GetScheduledEntries(t, r)
-		if diff := cmp.Diff(tc.wantScheduled, gotScheduled, h.IgnoreIDOpt); diff != "" {
-			t.Errorf("%s;\nmismatch found in %q; (-want,+got)\n%s", tc.desc, base.ScheduledQueue, diff)
+		for qname, want := range tc.wantScheduled {
+			gotScheduled := h.GetScheduledEntries(t, r, qname)
+			if diff := cmp.Diff(want, gotScheduled, h.IgnoreIDOpt, cmpopts.EquateEmpty()); diff != "" {
+				t.Errorf("%s;\nmismatch found in %q; (-want,+got)\n%s", tc.desc, base.ScheduledKey(qname), diff)
+			}
 		}
 	}
 }

 func TestClientEnqueue(t *testing.T) {
 	r := setup(t)
-	client := NewClient(RedisClientOpt{
-		Addr: redisAddr,
-		DB:   redisDB,
-	})
+	client := NewClient(getRedisConnOpt(t))
+	defer client.Close()

 	task := NewTask("send_email", map[string]interface{}{"to": "customer@gmail.com", "from": "merchant@example.com"})
+	now := time.Now()

 	tests := []struct {
-		desc         string
-		task         *Task
-		opts         []Option
-		wantRes      *Result
-		wantEnqueued map[string][]*base.TaskMessage
+		desc        string
+		task        *Task
+		opts        []Option
+		wantRes     *Result
+		wantPending map[string][]*base.TaskMessage
 	}{
 		{
 			desc: "Process task immediately with a custom retry count",
@@ -141,12 +154,13 @@ func TestClientEnqueue(t *testing.T) {
 				MaxRetry(3),
 			},
 			wantRes: &Result{
-				Queue:    "default",
-				Retry:    3,
-				Timeout:  defaultTimeout,
-				Deadline: noDeadline,
+				ProcessAt: now,
+				Queue:     "default",
+				Retry:     3,
+				Timeout:   defaultTimeout,
+				Deadline:  noDeadline,
 			},
-			wantEnqueued: map[string][]*base.TaskMessage{
+			wantPending: map[string][]*base.TaskMessage{
 				"default": {
 					{
 						Type:     task.Type,
@@ -166,12 +180,13 @@ func TestClientEnqueue(t *testing.T) {
 				MaxRetry(-2),
 			},
 			wantRes: &Result{
-				Queue:    "default",
-				Retry:    0,
-				Timeout:  defaultTimeout,
-				Deadline: noDeadline,
+				ProcessAt: now,
+				Queue:     "default",
+				Retry:     0,
+				Timeout:   defaultTimeout,
+				Deadline:  noDeadline,
 			},
-			wantEnqueued: map[string][]*base.TaskMessage{
+			wantPending: map[string][]*base.TaskMessage{
 				"default": {
 					{
 						Type:     task.Type,
@@ -192,12 +207,13 @@ func TestClientEnqueue(t *testing.T) {
 				MaxRetry(10),
 			},
 			wantRes: &Result{
-				Queue:    "default",
-				Retry:    10,
-				Timeout:  defaultTimeout,
-				Deadline: noDeadline,
+				ProcessAt: now,
+				Queue:     "default",
+				Retry:     10,
+				Timeout:   defaultTimeout,
+				Deadline:  noDeadline,
 			},
-			wantEnqueued: map[string][]*base.TaskMessage{
+			wantPending: map[string][]*base.TaskMessage{
 				"default": {
 					{
 						Type:     task.Type,
@@ -217,12 +233,13 @@ func TestClientEnqueue(t *testing.T) {
 				Queue("custom"),
 			},
 			wantRes: &Result{
-				Queue:    "custom",
-				Retry:    defaultMaxRetry,
-				Timeout:  defaultTimeout,
-				Deadline: noDeadline,
+				ProcessAt: now,
+				Queue:     "custom",
+				Retry:     defaultMaxRetry,
+				Timeout:   defaultTimeout,
+				Deadline:  noDeadline,
 			},
-			wantEnqueued: map[string][]*base.TaskMessage{
+			wantPending: map[string][]*base.TaskMessage{
 				"custom": {
 					{
 						Type:     task.Type,
@@ -242,12 +259,13 @@ func TestClientEnqueue(t *testing.T) {
 				Queue("HIGH"),
 			},
 			wantRes: &Result{
-				Queue:    "high",
-				Retry:    defaultMaxRetry,
-				Timeout:  defaultTimeout,
-				Deadline: noDeadline,
+				ProcessAt: now,
+				Queue:     "high",
+				Retry:     defaultMaxRetry,
+				Timeout:   defaultTimeout,
+				Deadline:  noDeadline,
 			},
-			wantEnqueued: map[string][]*base.TaskMessage{
+			wantPending: map[string][]*base.TaskMessage{
 				"high": {
 					{
 						Type:     task.Type,
@@ -267,12 +285,13 @@ func TestClientEnqueue(t *testing.T) {
 				Timeout(20 * time.Second),
 			},
 			wantRes: &Result{
-				Queue:    "default",
-				Retry:    defaultMaxRetry,
-				Timeout:  20 * time.Second,
-				Deadline: noDeadline,
+				ProcessAt: now,
+				Queue:     "default",
+				Retry:     defaultMaxRetry,
+				Timeout:   20 * time.Second,
+				Deadline:  noDeadline,
 			},
-			wantEnqueued: map[string][]*base.TaskMessage{
+			wantPending: map[string][]*base.TaskMessage{
 				"default": {
 					{
 						Type:     task.Type,
@@ -292,12 +311,13 @@ func TestClientEnqueue(t *testing.T) {
 				Deadline(time.Date(2020, time.June, 24, 0, 0, 0, 0, time.UTC)),
 			},
 			wantRes: &Result{
-				Queue:    "default",
-				Retry:    defaultMaxRetry,
-				Timeout:  noTimeout,
-				Deadline: time.Date(2020, time.June, 24, 0, 0, 0, 0, time.UTC),
+				ProcessAt: now,
+				Queue:     "default",
+				Retry:     defaultMaxRetry,
+				Timeout:   noTimeout,
+				Deadline:  time.Date(2020, time.June, 24, 0, 0, 0, 0, time.UTC),
 			},
-			wantEnqueued: map[string][]*base.TaskMessage{
+			wantPending: map[string][]*base.TaskMessage{
 				"default": {
 					{
 						Type:     task.Type,
@@ -318,12 +338,13 @@ func TestClientEnqueue(t *testing.T) {
 				Deadline(time.Date(2020, time.June, 24, 0, 0, 0, 0, time.UTC)),
 			},
 			wantRes: &Result{
-				Queue:    "default",
-				Retry:    defaultMaxRetry,
-				Timeout:  20 * time.Second,
-				Deadline: time.Date(2020, time.June, 24, 0, 0, 0, 0, time.UTC),
+				ProcessAt: now,
+				Queue:     "default",
+				Retry:     defaultMaxRetry,
+				Timeout:   20 * time.Second,
+				Deadline:  time.Date(2020, time.June, 24, 0, 0, 0, 0, time.UTC),
 			},
-			wantEnqueued: map[string][]*base.TaskMessage{
+			wantPending: map[string][]*base.TaskMessage{
 				"default": {
 					{
 						Type:     task.Type,
@@ -346,13 +367,17 @@ func TestClientEnqueue(t *testing.T) {
 			t.Error(err)
 			continue
 		}
-		if diff := cmp.Diff(tc.wantRes, gotRes, cmpopts.IgnoreFields(Result{}, "ID")); diff != "" {
+		cmpOptions := []cmp.Option{
+			cmpopts.IgnoreFields(Result{}, "ID", "EnqueuedAt"),
+			cmpopts.EquateApproxTime(500 * time.Millisecond),
+		}
+		if diff := cmp.Diff(tc.wantRes, gotRes, cmpOptions...); diff != "" {
 			t.Errorf("%s;\nEnqueue(task) returned %v, want %v; (-want,+got)\n%s",
 				tc.desc, gotRes, tc.wantRes, diff)
 		}

-		for qname, want := range tc.wantEnqueued {
-			got := h.GetEnqueuedMessages(t, r, qname)
+		for qname, want := range tc.wantPending {
+			got := h.GetPendingMessages(t, r, qname)
 			if diff := cmp.Diff(want, got, h.IgnoreIDOpt); diff != "" {
 				t.Errorf("%s;\nmismatch found in %q; (-want,+got)\n%s", tc.desc, base.QueueKey(qname), diff)
 			}
@@ -360,47 +385,51 @@ func TestClientEnqueue(t *testing.T) {
 	}
 }

-func TestClientEnqueueIn(t *testing.T) {
+func TestClientEnqueueWithProcessInOption(t *testing.T) {
 	r := setup(t)
-	client := NewClient(RedisClientOpt{
-		Addr: redisAddr,
-		DB:   redisDB,
-	})
+	client := NewClient(getRedisConnOpt(t))
+	defer client.Close()

 	task := NewTask("send_email", map[string]interface{}{"to": "customer@gmail.com", "from": "merchant@example.com"})
+	now := time.Now()

 	tests := []struct {
 		desc          string
 		task          *Task
-		delay         time.Duration
-		opts          []Option
+		delay         time.Duration // value for ProcessIn option
+		opts          []Option      // other options
 		wantRes       *Result
-		wantEnqueued  map[string][]*base.TaskMessage
-		wantScheduled []h.ZSetEntry
+		wantPending   map[string][]*base.TaskMessage
+		wantScheduled map[string][]base.Z
 	}{
 		{
-			desc:  "schedule a task to be enqueued in one hour",
+			desc:  "schedule a task to be processed in one hour",
 			task:  task,
-			delay: time.Hour,
+			delay: 1 * time.Hour,
 			opts:  []Option{},
 			wantRes: &Result{
-				Queue:    "default",
-				Retry:    defaultMaxRetry,
-				Timeout:  defaultTimeout,
-				Deadline: noDeadline,
+				ProcessAt: now.Add(1 * time.Hour),
+				Queue:     "default",
+				Retry:     defaultMaxRetry,
+				Timeout:   defaultTimeout,
+				Deadline:  noDeadline,
 			},
-			wantEnqueued: nil, // db is flushed in setup so list does not exist hence nil
-			wantScheduled: []h.ZSetEntry{
-				{
-					Msg: &base.TaskMessage{
-						Type:     task.Type,
-						Payload:  task.Payload.data,
-						Retry:    defaultMaxRetry,
-						Queue:    "default",
-						Timeout:  int64(defaultTimeout.Seconds()),
-						Deadline: noDeadline.Unix(),
+			wantPending: map[string][]*base.TaskMessage{
+				"default": {},
+			},
+			wantScheduled: map[string][]base.Z{
+				"default": {
+					{
+						Message: &base.TaskMessage{
+							Type:     task.Type,
+							Payload:  task.Payload.data,
+							Retry:    defaultMaxRetry,
+							Queue:    "default",
+							Timeout:  int64(defaultTimeout.Seconds()),
+							Deadline: noDeadline.Unix(),
+						},
+						Score: time.Now().Add(time.Hour).Unix(),
 					},
-					Score: float64(time.Now().Add(time.Hour).Unix()),
 				},
 			},
 		},
@@ -410,12 +439,13 @@ func TestClientEnqueueIn(t *testing.T) {
 			delay: 0,
 			opts:  []Option{},
 			wantRes: &Result{
-				Queue:    "default",
-				Retry:    defaultMaxRetry,
-				Timeout:  defaultTimeout,
-				Deadline: noDeadline,
+				ProcessAt: now,
+				Queue:     "default",
+				Retry:     defaultMaxRetry,
+				Timeout:   defaultTimeout,
+				Deadline:  noDeadline,
 			},
-			wantEnqueued: map[string][]*base.TaskMessage{
+			wantPending: map[string][]*base.TaskMessage{
 				"default": {
 					{
 						Type:     task.Type,
@@ -427,33 +457,72 @@ func TestClientEnqueueIn(t *testing.T) {
 					},
 				},
 			},
-			wantScheduled: nil, // db is flushed in setup so zset does not exist hence nil
+			wantScheduled: map[string][]base.Z{
+				"default": {},
+			},
 		},
 	}

 	for _, tc := range tests {
 		h.FlushDB(t, r) // clean up db before each test case.

-		gotRes, err := client.EnqueueIn(tc.delay, tc.task, tc.opts...)
+		opts := append(tc.opts, ProcessIn(tc.delay))
+		gotRes, err := client.Enqueue(tc.task, opts...)
 		if err != nil {
 			t.Error(err)
 			continue
 		}
-		if diff := cmp.Diff(tc.wantRes, gotRes, cmpopts.IgnoreFields(Result{}, "ID")); diff != "" {
-			t.Errorf("%s;\nEnqueueIn(delay, task) returned %v, want %v; (-want,+got)\n%s",
-				tc.desc, gotRes, tc.wantRes, diff)
+		cmpOptions := []cmp.Option{
+			cmpopts.IgnoreFields(Result{}, "ID", "EnqueuedAt"),
+			cmpopts.EquateApproxTime(500 * time.Millisecond),
+		}
+		if diff := cmp.Diff(tc.wantRes, gotRes, cmpOptions...); diff != "" {
+			t.Errorf("%s;\nEnqueue(task, ProcessIn(%v)) returned %v, want %v; (-want,+got)\n%s",
+				tc.desc, tc.delay, gotRes, tc.wantRes, diff)
 		}

-		for qname, want := range tc.wantEnqueued {
-			gotEnqueued := h.GetEnqueuedMessages(t, r, qname)
-			if diff := cmp.Diff(want, gotEnqueued, h.IgnoreIDOpt); diff != "" {
+		for qname, want := range tc.wantPending {
+			gotPending := h.GetPendingMessages(t, r, qname)
+			if diff := cmp.Diff(want, gotPending, h.IgnoreIDOpt, cmpopts.EquateEmpty()); diff != "" {
 				t.Errorf("%s;\nmismatch found in %q; (-want,+got)\n%s", tc.desc, base.QueueKey(qname), diff)
 			}
 		}
+		for qname, want := range tc.wantScheduled {
+			gotScheduled := h.GetScheduledEntries(t, r, qname)
+			if diff := cmp.Diff(want, gotScheduled, h.IgnoreIDOpt, cmpopts.EquateEmpty()); diff != "" {
+				t.Errorf("%s;\nmismatch found in %q; (-want,+got)\n%s", tc.desc, base.ScheduledKey(qname), diff)
+			}
+		}
+	}
+}

-		gotScheduled := h.GetScheduledEntries(t, r)
-		if diff := cmp.Diff(tc.wantScheduled, gotScheduled, h.IgnoreIDOpt); diff != "" {
-			t.Errorf("%s;\nmismatch found in %q; (-want,+got)\n%s", tc.desc, base.ScheduledQueue, diff)
+func TestClientEnqueueError(t *testing.T) {
+	r := setup(t)
+	client := NewClient(getRedisConnOpt(t))
+	defer client.Close()
+
+	task := NewTask("send_email", map[string]interface{}{"to": "customer@gmail.com", "from": "merchant@example.com"})
+
+	tests := []struct {
+		desc string
+		task *Task
+		opts []Option
+	}{
+		{
+			desc: "With empty queue name",
+			task: task,
+			opts: []Option{
+				Queue(""),
+			},
+		},
+	}
+
+	for _, tc := range tests {
+		h.FlushDB(t, r)
+
+		_, err := client.Enqueue(tc.task, tc.opts...)
+		if err == nil {
+			t.Errorf("%s; client.Enqueue(task, opts...) did not return non-nil error", tc.desc)
 		}
 	}
 }
@@ -461,6 +530,8 @@ func TestClientEnqueueIn(t *testing.T) {
 func TestClientDefaultOptions(t *testing.T) {
 	r := setup(t)

+	now := time.Now()
+
 	tests := []struct {
 		desc        string
 		defaultOpts []Option // options set at the client level.
@@ -476,10 +547,11 @@ func TestClientDefaultOptions(t *testing.T) {
 			opts:        []Option{},
 			task:        NewTask("feed:import", nil),
 			wantRes: &Result{
-				Queue:    "feed",
-				Retry:    defaultMaxRetry,
-				Timeout:  defaultTimeout,
-				Deadline: noDeadline,
+				ProcessAt: now,
+				Queue:     "feed",
+				Retry:     defaultMaxRetry,
+				Timeout:   defaultTimeout,
+				Deadline:  noDeadline,
 			},
 			queue: "feed",
 			want: &base.TaskMessage{
@@ -497,10 +569,11 @@ func TestClientDefaultOptions(t *testing.T) {
 			opts:        []Option{},
 			task:        NewTask("feed:import", nil),
 			wantRes: &Result{
-				Queue:    "feed",
-				Retry:    5,
-				Timeout:  defaultTimeout,
-				Deadline: noDeadline,
+				ProcessAt: now,
+				Queue:     "feed",
+				Retry:     5,
+				Timeout:   defaultTimeout,
+				Deadline:  noDeadline,
 			},
 			queue: "feed",
 			want: &base.TaskMessage{
@@ -518,10 +591,11 @@ func TestClientDefaultOptions(t *testing.T) {
 			opts:        []Option{Queue("critical")},
 			task:        NewTask("feed:import", nil),
 			wantRes: &Result{
-				Queue:    "critical",
-				Retry:    5,
-				Timeout:  defaultTimeout,
-				Deadline: noDeadline,
+				ProcessAt: now,
+				Queue:     "critical",
+				Retry:     5,
+				Timeout:   defaultTimeout,
+				Deadline:  noDeadline,
 			},
 			queue: "critical",
 			want: &base.TaskMessage{
@@ -537,102 +611,39 @@ func TestClientDefaultOptions(t *testing.T) {

 	for _, tc := range tests {
 		h.FlushDB(t, r)
-		c := NewClient(RedisClientOpt{Addr: redisAddr, DB: redisDB})
+		c := NewClient(getRedisConnOpt(t))
+		defer c.Close()
 		c.SetDefaultOptions(tc.task.Type, tc.defaultOpts...)
 		gotRes, err := c.Enqueue(tc.task, tc.opts...)
 		if err != nil {
 			t.Fatal(err)
 		}
-		if diff := cmp.Diff(tc.wantRes, gotRes, cmpopts.IgnoreFields(Result{}, "ID")); diff != "" {
+		cmpOptions := []cmp.Option{
+			cmpopts.IgnoreFields(Result{}, "ID", "EnqueuedAt"),
+			cmpopts.EquateApproxTime(500 * time.Millisecond),
+		}
+		if diff := cmp.Diff(tc.wantRes, gotRes, cmpOptions...); diff != "" {
 			t.Errorf("%s;\nEnqueue(task, opts...) returned %v, want %v; (-want,+got)\n%s",
 				tc.desc, gotRes, tc.wantRes, diff)
 		}
-		enqueued := h.GetEnqueuedMessages(t, r, tc.queue)
-		if len(enqueued) != 1 {
+		pending := h.GetPendingMessages(t, r, tc.queue)
+		if len(pending) != 1 {
 			t.Errorf("%s;\nexpected queue %q to have one message; got %d messages in the queue.",
-				tc.desc, tc.queue, len(enqueued))
+				tc.desc, tc.queue, len(pending))
 			continue
 		}
-		got := enqueued[0]
+		got := pending[0]
 		if diff := cmp.Diff(tc.want, got, h.IgnoreIDOpt); diff != "" {
-			t.Errorf("%s;\nmismatch found in enqueued task message; (-want,+got)\n%s",
+			t.Errorf("%s;\nmismatch found in pending task message; (-want,+got)\n%s",
 				tc.desc, diff)
 		}
 	}
 }

-func TestUniqueKey(t *testing.T) {
-	tests := []struct {
-		desc  string
-		task  *Task
-		ttl   time.Duration
-		qname string
-		want  string
-	}{
-		{
-			"with zero TTL",
-			NewTask("email:send", map[string]interface{}{"a": 123, "b": "hello", "c": true}),
-			0,
-			"default",
-			"",
-		},
-		{
-			"with primitive types",
-			NewTask("email:send", map[string]interface{}{"a": 123, "b": "hello", "c": true}),
-			10 * time.Minute,
-			"default",
-			"email:send:a=123,b=hello,c=true:default",
-		},
-		{
-			"with unsorted keys",
-			NewTask("email:send", map[string]interface{}{"b": "hello", "c": true, "a": 123}),
-			10 * time.Minute,
-			"default",
-			"email:send:a=123,b=hello,c=true:default",
-		},
-		{
-			"with composite types",
-			NewTask("email:send",
-				map[string]interface{}{
-					"address": map[string]string{"line": "123 Main St", "city": "Boston", "state": "MA"},
-					"names":   []string{"bob", "mike", "rob"}}),
-			10 * time.Minute,
-			"default",
-			"email:send:address=map[city:Boston line:123 Main St state:MA],names=[bob mike rob]:default",
-		},
-		{
-			"with complex types",
-			NewTask("email:send",
-				map[string]interface{}{
-					"time":     time.Date(2020, time.July, 28, 0, 0, 0, 0, time.UTC),
-					"duration": time.Hour}),
-			10 * time.Minute,
-			"default",
-			"email:send:duration=1h0m0s,time=2020-07-28 00:00:00 +0000 UTC:default",
-		},
-		{
-			"with nil payload",
-			NewTask("reindex", nil),
-			10 * time.Minute,
-			"default",
-			"reindex:nil:default",
-		},
-	}
-
-	for _, tc := range tests {
-		got := uniqueKey(tc.task, tc.ttl, tc.qname)
-		if got != tc.want {
-			t.Errorf("%s: uniqueKey(%v, %v, %q) = %q, want %q", tc.desc, tc.task, tc.ttl, tc.qname, got, tc.want)
-		}
-	}
-}
-
-func TestEnqueueUnique(t *testing.T) {
+func TestClientEnqueueUnique(t *testing.T) {
 	r := setup(t)
-	c := NewClient(RedisClientOpt{
-		Addr: redisAddr,
-		DB:   redisDB,
-	})
+	c := NewClient(getRedisConnOpt(t))
+	defer c.Close()

 	tests := []struct {
 		task *Task
@@ -653,7 +664,7 @@ func TestEnqueueUnique(t *testing.T) {
 			t.Fatal(err)
 		}

-		gotTTL := r.TTL(uniqueKey(tc.task, tc.ttl, base.DefaultQueueName)).Val()
+		gotTTL := r.TTL(base.UniqueKey(base.DefaultQueueName, tc.task.Type, tc.task.Payload.data)).Val()
 		if !cmp.Equal(tc.ttl.Seconds(), gotTTL.Seconds(), cmpopts.EquateApprox(0, 1)) {
 			t.Errorf("TTL = %v, want %v", gotTTL, tc.ttl)
 			continue
@@ -672,12 +683,10 @@ func TestEnqueueUnique(t *testing.T) {
 	}
 }

-func TestEnqueueInUnique(t *testing.T) {
+func TestClientEnqueueUniqueWithProcessInOption(t *testing.T) {
 	r := setup(t)
-	c := NewClient(RedisClientOpt{
-		Addr: redisAddr,
-		DB:   redisDB,
-	})
+	c := NewClient(getRedisConnOpt(t))
+	defer c.Close()

 	tests := []struct {
 		task *Task
@@ -695,12 +704,12 @@ func TestEnqueueInUnique(t *testing.T) {
 		h.FlushDB(t, r) // clean up db before each test case.

 		// Enqueue the task first. It should succeed.
-		_, err := c.EnqueueIn(tc.d, tc.task, Unique(tc.ttl))
+		_, err := c.Enqueue(tc.task, ProcessIn(tc.d), Unique(tc.ttl))
 		if err != nil {
 			t.Fatal(err)
 		}

-		gotTTL := r.TTL(uniqueKey(tc.task, tc.ttl, base.DefaultQueueName)).Val()
+		gotTTL := r.TTL(base.UniqueKey(base.DefaultQueueName, tc.task.Type, tc.task.Payload.data)).Val()
 		wantTTL := time.Duration(tc.ttl.Seconds()+tc.d.Seconds()) * time.Second
 		if !cmp.Equal(wantTTL.Seconds(), gotTTL.Seconds(), cmpopts.EquateApprox(0, 1)) {
 			t.Errorf("TTL = %v, want %v", gotTTL, wantTTL)
@@ -708,7 +717,7 @@ func TestEnqueueInUnique(t *testing.T) {
 		}

 		// Enqueue the task again. It should fail.
-		_, err = c.EnqueueIn(tc.d, tc.task, Unique(tc.ttl))
+		_, err = c.Enqueue(tc.task, ProcessIn(tc.d), Unique(tc.ttl))
 		if err == nil {
 			t.Errorf("Enqueueing %+v did not return an error", tc.task)
 			continue
@@ -720,12 +729,10 @@ func TestEnqueueInUnique(t *testing.T) {
 	}
 }

-func TestEnqueueAtUnique(t *testing.T) {
+func TestClientEnqueueUniqueWithProcessAtOption(t *testing.T) {
 	r := setup(t)
-	c := NewClient(RedisClientOpt{
-		Addr: redisAddr,
-		DB:   redisDB,
-	})
+	c := NewClient(getRedisConnOpt(t))
+	defer c.Close()

 	tests := []struct {
 		task *Task
@@ -743,12 +750,12 @@ func TestEnqueueAtUnique(t *testing.T) {
 		h.FlushDB(t, r) // clean up db before each test case.

 		// Enqueue the task first. It should succeed.
-		_, err := c.EnqueueAt(tc.at, tc.task, Unique(tc.ttl))
+		_, err := c.Enqueue(tc.task, ProcessAt(tc.at), Unique(tc.ttl))
 		if err != nil {
 			t.Fatal(err)
 		}

-		gotTTL := r.TTL(uniqueKey(tc.task, tc.ttl, base.DefaultQueueName)).Val()
+		gotTTL := r.TTL(base.UniqueKey(base.DefaultQueueName, tc.task.Type, tc.task.Payload.data)).Val()
 		wantTTL := tc.at.Add(tc.ttl).Sub(time.Now())
 		if !cmp.Equal(wantTTL.Seconds(), gotTTL.Seconds(), cmpopts.EquateApprox(0, 1)) {
 			t.Errorf("TTL = %v, want %v", gotTTL, wantTTL)
@@ -756,7 +763,7 @@ func TestEnqueueAtUnique(t *testing.T) {
 		}

 		// Enqueue the task again. It should fail.
-		_, err = c.EnqueueAt(tc.at, tc.task, Unique(tc.ttl))
+		_, err = c.Enqueue(tc.task, ProcessAt(tc.at), Unique(tc.ttl))
 		if err == nil {
 			t.Errorf("Enqueueing %+v did not return an error", tc.task)
 			continue
@@ -767,3 +774,71 @@ func TestEnqueueAtUnique(t *testing.T) {
 		}
 	}
 }
+
+func TestParseOption(t *testing.T) {
+	oneHourFromNow := time.Now().Add(1 * time.Hour)
+	tests := []struct {
+		s        string
+		wantType OptionType
+		wantVal  interface{}
+	}{
+		{`MaxRetry(10)`, MaxRetryOpt, 10},
+		{`Queue("email")`, QueueOpt, "email"},
+		{`Timeout(3m)`, TimeoutOpt, 3 * time.Minute},
+		{Deadline(oneHourFromNow).String(), DeadlineOpt, oneHourFromNow},
+		{`Unique(1h)`, UniqueOpt, 1 * time.Hour},
+		{ProcessAt(oneHourFromNow).String(), ProcessAtOpt, oneHourFromNow},
+		{`ProcessIn(10m)`, ProcessInOpt, 10 * time.Minute},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.s, func(t *testing.T) {
+			got, err := parseOption(tc.s)
+			if err != nil {
+				t.Fatalf("returned error: %v", err)
+			}
+			if got == nil {
+				t.Fatal("returned nil")
+			}
+			if got.Type() != tc.wantType {
+				t.Fatalf("got type %v, want type %v ", got.Type(), tc.wantType)
+			}
+			switch tc.wantType {
+			case QueueOpt:
+				gotVal, ok := got.Value().(string)
+				if !ok {
+					t.Fatal("returned Option with non-string value")
+				}
+				if gotVal != tc.wantVal.(string) {
+					t.Fatalf("got value %v, want %v", gotVal, tc.wantVal)
+				}
+			case MaxRetryOpt:
+				gotVal, ok := got.Value().(int)
+				if !ok {
+					t.Fatal("returned Option with non-int value")
+				}
+				if gotVal != tc.wantVal.(int) {
+					t.Fatalf("got value %v, want %v", gotVal, tc.wantVal)
+				}
+			case TimeoutOpt, UniqueOpt, ProcessInOpt:
+				gotVal, ok := got.Value().(time.Duration)
+				if !ok {
+					t.Fatal("returned Option with non duration value")
+				}
+				if gotVal != tc.wantVal.(time.Duration) {
+					t.Fatalf("got value %v, want %v", gotVal, tc.wantVal)
+				}
+			case DeadlineOpt, ProcessAtOpt:
+				gotVal, ok := got.Value().(time.Time)
+				if !ok {
+					t.Fatal("returned Option with non time value")
+				}
+				if cmp.Equal(gotVal, tc.wantVal.(time.Time)) {
+					t.Fatalf("got value %v, want %v", gotVal, tc.wantVal)
+				}
+			default:
+				t.Fatalf("returned Option with unexpected type: %v", got.Type())
+			}
+		})
+	}
+}
--- a/context.go
+++ b/context.go
@@ -16,6 +16,7 @@ type taskMetadata struct {
 	id         string
 	maxRetry   int
 	retryCount int
+	qname      string
 }

 // ctxKey type is unexported to prevent collisions with context keys defined in
@@ -32,6 +33,7 @@ func createContext(msg *base.TaskMessage, deadline time.Time) (context.Context,
 		id:         msg.ID.String(),
 		maxRetry:   msg.Retry,
 		retryCount: msg.Retried,
+		qname:      msg.Queue,
 	}
 	ctx := context.WithValue(context.Background(), metadataCtxKey, metadata)
 	return context.WithDeadline(ctx, deadline)
@@ -72,3 +74,14 @@ func GetMaxRetry(ctx context.Context) (n int, ok bool) {
 	}
 	return metadata.maxRetry, true
 }
+
+// GetQueueName extracts queue name from a context, if any.
+//
+// Return value qname indicates which queue the task was pulled from.
+func GetQueueName(ctx context.Context) (qname string, ok bool) {
+	metadata, ok := ctx.Value(metadataCtxKey).(taskMetadata)
+	if !ok {
+		return "", false
+	}
+	return metadata.qname, true
+}
--- a/context_test.go
+++ b/context_test.go
@@ -92,8 +92,9 @@ func TestGetTaskMetadataFromContext(t *testing.T) {
 		desc string
 		msg  *base.TaskMessage
 	}{
-		{"with zero retried message", &base.TaskMessage{Type: "something", ID: uuid.New(), Retry: 25, Retried: 0, Timeout: 1800}},
-		{"with non-zero retried message", &base.TaskMessage{Type: "something", ID: uuid.New(), Retry: 10, Retried: 5, Timeout: 1800}},
+		{"with zero retried message", &base.TaskMessage{Type: "something", ID: uuid.New(), Retry: 25, Retried: 0, Timeout: 1800, Queue: "default"}},
+		{"with non-zero retried message", &base.TaskMessage{Type: "something", ID: uuid.New(), Retry: 10, Retried: 5, Timeout: 1800, Queue: "default"}},
+		{"with custom queue name", &base.TaskMessage{Type: "something", ID: uuid.New(), Retry: 25, Retried: 0, Timeout: 1800, Queue: "custom"}},
 	}

 	for _, tc := range tests {
@@ -123,6 +124,14 @@ func TestGetTaskMetadataFromContext(t *testing.T) {
 		if ok && maxRetry != tc.msg.Retry {
 			t.Errorf("%s: GetMaxRetry(ctx) returned n == %d want %d", tc.desc, maxRetry, tc.msg.Retry)
 		}
+
+		qname, ok := GetQueueName(ctx)
+		if !ok {
+			t.Errorf("%s: GetQueueName(ctx) returned ok == false", tc.desc)
+		}
+		if ok && qname != tc.msg.Queue {
+			t.Errorf("%s: GetQueueName(ctx) returned qname == %q, want %q", tc.desc, qname, tc.msg.Queue)
+		}
 	}
 }

@@ -144,5 +153,8 @@ func TestGetTaskMetadataFromContextError(t *testing.T) {
 		if _, ok := GetMaxRetry(tc.ctx); ok {
 			t.Errorf("%s: GetMaxRetry(ctx) returned ok == true", tc.desc)
 		}
+		if _, ok := GetQueueName(tc.ctx); ok {
+			t.Errorf("%s: GetQueueName(ctx) returned ok == true", tc.desc)
+		}
 	}
 }
--- a/doc.go
+++ b/doc.go
@@ -3,23 +3,23 @@
 // that can be found in the LICENSE file.

 /*
-Package asynq provides a framework for asynchronous task processing.
+Package asynq provides a framework for Redis based distrubted task queue.

-Asynq uses Redis as a message broker. To connect to redis server,
-specify the options using one of RedisConnOpt types.
+Asynq uses Redis as a message broker. To connect to redis,
+specify the connection using one of RedisConnOpt types.

-    redis = &asynq.RedisClientOpt{
+    redisConnOpt = asynq.RedisClientOpt{
        Addr:     "127.0.0.1:6379",
        Password: "xxxxx",
        DB:       3,
    }

-The Client is used to enqueue a task to be processed at the specified time.
+The Client is used to enqueue a task.

-Task is created with two parameters: its type and payload.

-    client := asynq.NewClient(redis)
+    client := asynq.NewClient(redisConnOpt)

+    // Task is created with two parameters: its type and payload.
    t := asynq.NewTask(
        "send_email",
        map[string]interface{}{"user_id": 42})
@@ -28,15 +28,17 @@ Task is created with two parameters: its type and payload.
    res, err := client.Enqueue(t)

    // Schedule the task to be processed after one minute.
-    res, err = client.EnqueueIn(time.Minute, t)
+    res, err = client.Enqueue(t, asynq.ProcessIn(1*time.Minute))

-The Server is used to run the background task processing with a given
+The Server is used to run the task processing workers with a given
 handler.
-    srv := asynq.NewServer(redis, asynq.Config{
+    srv := asynq.NewServer(redisConnOpt, asynq.Config{
        Concurrency: 10,
    })

-    srv.Run(handler)
+    if err := srv.Run(handler); err != nil {
+        log.Fatal(err)
+    }

 Handler is an interface type with a method which
 takes a task and returns an error. Handler should return nil if
--- a/docs/assets/cluster.png
+++ b/docs/assets/cluster.png
--- a/docs/assets/demo.gif
+++ b/docs/assets/demo.gif
--- a/example_test.go
+++ b/example_test.go
@@ -9,6 +9,7 @@ import (
 	"log"
 	"os"
 	"os/signal"
+	"time"

 	"github.com/hibiken/asynq"
 	"golang.org/x/sys/unix"
@@ -78,6 +79,25 @@ func ExampleServer_Quiet() {
 	srv.Stop()
 }

+func ExampleScheduler() {
+	scheduler := asynq.NewScheduler(
+		asynq.RedisClientOpt{Addr: ":6379"},
+		&asynq.SchedulerOpts{Location: time.Local},
+	)
+
+	if _, err := scheduler.Register("* * * * *", asynq.NewTask("task1", nil)); err != nil {
+		log.Fatal(err)
+	}
+	if _, err := scheduler.Register("@every 30s", asynq.NewTask("task2", nil)); err != nil {
+		log.Fatal(err)
+	}
+
+	// Run blocks and waits for os signal to terminate the program.
+	if err := scheduler.Run(); err != nil {
+		log.Fatal(err)
+	}
+}
+
 func ExampleParseRedisURI() {
 	rconn, err := asynq.ParseRedisURI("redis://localhost:6379/10")
 	if err != nil {
--- a/forwarder.go
+++ b/forwarder.go
@@ -0,0 +1,75 @@
+// Copyright 2020 Kentaro Hibino. All rights reserved.
+// Use of this source code is governed by a MIT license
+// that can be found in the LICENSE file.
+
+package asynq
+
+import (
+	"sync"
+	"time"
+
+	"github.com/hibiken/asynq/internal/base"
+	"github.com/hibiken/asynq/internal/log"
+)
+
+// A forwarder is responsible for moving scheduled and retry tasks to pending state
+// so that the tasks get processed by the workers.
+type forwarder struct {
+	logger *log.Logger
+	broker base.Broker
+
+	// channel to communicate back to the long running "forwarder" goroutine.
+	done chan struct{}
+
+	// list of queue names to check and enqueue.
+	queues []string
+
+	// poll interval on average
+	avgInterval time.Duration
+}
+
+type forwarderParams struct {
+	logger   *log.Logger
+	broker   base.Broker
+	queues   []string
+	interval time.Duration
+}
+
+func newForwarder(params forwarderParams) *forwarder {
+	return &forwarder{
+		logger:      params.logger,
+		broker:      params.broker,
+		done:        make(chan struct{}),
+		queues:      params.queues,
+		avgInterval: params.interval,
+	}
+}
+
+func (f *forwarder) terminate() {
+	f.logger.Debug("Forwarder shutting down...")
+	// Signal the forwarder goroutine to stop polling.
+	f.done <- struct{}{}
+}
+
+// start starts the "forwarder" goroutine.
+func (f *forwarder) start(wg *sync.WaitGroup) {
+	wg.Add(1)
+	go func() {
+		defer wg.Done()
+		for {
+			select {
+			case <-f.done:
+				f.logger.Debug("Forwarder done")
+				return
+			case <-time.After(f.avgInterval):
+				f.exec()
+			}
+		}
+	}()
+}
+
+func (f *forwarder) exec() {
+	if err := f.broker.CheckAndEnqueue(f.queues...); err != nil {
+		f.logger.Errorf("Could not enqueue scheduled tasks: %v", err)
+	}
+}
--- a/forwarder_test.go
+++ b/forwarder_test.go
@@ -0,0 +1,137 @@
+// Copyright 2020 Kentaro Hibino. All rights reserved.
+// Use of this source code is governed by a MIT license
+// that can be found in the LICENSE file.
+
+package asynq
+
+import (
+	"sync"
+	"testing"
+	"time"
+
+	"github.com/google/go-cmp/cmp"
+	h "github.com/hibiken/asynq/internal/asynqtest"
+	"github.com/hibiken/asynq/internal/base"
+	"github.com/hibiken/asynq/internal/rdb"
+)
+
+func TestForwarder(t *testing.T) {
+	r := setup(t)
+	defer r.Close()
+	rdbClient := rdb.NewRDB(r)
+	const pollInterval = time.Second
+	s := newForwarder(forwarderParams{
+		logger:   testLogger,
+		broker:   rdbClient,
+		queues:   []string{"default", "critical"},
+		interval: pollInterval,
+	})
+	t1 := h.NewTaskMessageWithQueue("gen_thumbnail", nil, "default")
+	t2 := h.NewTaskMessageWithQueue("send_email", nil, "critical")
+	t3 := h.NewTaskMessageWithQueue("reindex", nil, "default")
+	t4 := h.NewTaskMessageWithQueue("sync", nil, "critical")
+	now := time.Now()
+
+	tests := []struct {
+		initScheduled map[string][]base.Z            // scheduled queue initial state
+		initRetry     map[string][]base.Z            // retry queue initial state
+		initPending   map[string][]*base.TaskMessage // default queue initial state
+		wait          time.Duration                  // wait duration before checking for final state
+		wantScheduled map[string][]*base.TaskMessage // schedule queue final state
+		wantRetry     map[string][]*base.TaskMessage // retry queue final state
+		wantPending   map[string][]*base.TaskMessage // default queue final state
+	}{
+		{
+			initScheduled: map[string][]base.Z{
+				"default":  {{Message: t1, Score: now.Add(time.Hour).Unix()}},
+				"critical": {{Message: t2, Score: now.Add(-2 * time.Second).Unix()}},
+			},
+			initRetry: map[string][]base.Z{
+				"default":  {{Message: t3, Score: time.Now().Add(-500 * time.Millisecond).Unix()}},
+				"critical": {},
+			},
+			initPending: map[string][]*base.TaskMessage{
+				"default":  {},
+				"critical": {t4},
+			},
+			wait: pollInterval * 2,
+			wantScheduled: map[string][]*base.TaskMessage{
+				"default":  {t1},
+				"critical": {},
+			},
+			wantRetry: map[string][]*base.TaskMessage{
+				"default":  {},
+				"critical": {},
+			},
+			wantPending: map[string][]*base.TaskMessage{
+				"default":  {t3},
+				"critical": {t2, t4},
+			},
+		},
+		{
+			initScheduled: map[string][]base.Z{
+				"default": {
+					{Message: t1, Score: now.Unix()},
+					{Message: t3, Score: now.Add(-500 * time.Millisecond).Unix()},
+				},
+				"critical": {
+					{Message: t2, Score: now.Add(-2 * time.Second).Unix()},
+				},
+			},
+			initRetry: map[string][]base.Z{
+				"default":  {},
+				"critical": {},
+			},
+			initPending: map[string][]*base.TaskMessage{
+				"default":  {},
+				"critical": {t4},
+			},
+			wait: pollInterval * 2,
+			wantScheduled: map[string][]*base.TaskMessage{
+				"default":  {},
+				"critical": {},
+			},
+			wantRetry: map[string][]*base.TaskMessage{
+				"default":  {},
+				"critical": {},
+			},
+			wantPending: map[string][]*base.TaskMessage{
+				"default":  {t1, t3},
+				"critical": {t2, t4},
+			},
+		},
+	}
+
+	for _, tc := range tests {
+		h.FlushDB(t, r)                                  // clean up db before each test case.
+		h.SeedAllScheduledQueues(t, r, tc.initScheduled) // initialize scheduled queue
+		h.SeedAllRetryQueues(t, r, tc.initRetry)         // initialize retry queue
+		h.SeedAllPendingQueues(t, r, tc.initPending)     // initialize default queue
+
+		var wg sync.WaitGroup
+		s.start(&wg)
+		time.Sleep(tc.wait)
+		s.terminate()
+
+		for qname, want := range tc.wantScheduled {
+			gotScheduled := h.GetScheduledMessages(t, r, qname)
+			if diff := cmp.Diff(want, gotScheduled, h.SortMsgOpt); diff != "" {
+				t.Errorf("mismatch found in %q after running forwarder: (-want, +got)\n%s", base.ScheduledKey(qname), diff)
+			}
+		}
+
+		for qname, want := range tc.wantRetry {
+			gotRetry := h.GetRetryMessages(t, r, qname)
+			if diff := cmp.Diff(want, gotRetry, h.SortMsgOpt); diff != "" {
+				t.Errorf("mismatch found in %q after running forwarder: (-want, +got)\n%s", base.RetryKey(qname), diff)
+			}
+		}
+
+		for qname, want := range tc.wantPending {
+			gotPending := h.GetPendingMessages(t, r, qname)
+			if diff := cmp.Diff(want, gotPending, h.SortMsgOpt); diff != "" {
+				t.Errorf("mismatch found in %q after running forwarder: (-want, +got)\n%s", base.QueueKey(qname), diff)
+			}
+		}
+	}
+}
--- a/go.mod
+++ b/go.mod
@@ -3,9 +3,10 @@ module github.com/hibiken/asynq
 go 1.13

 require (
-	github.com/go-redis/redis/v7 v7.2.0
+	github.com/go-redis/redis/v7 v7.4.0
 	github.com/google/go-cmp v0.4.0
 	github.com/google/uuid v1.1.1
+	github.com/robfig/cron/v3 v3.0.1
 	github.com/spf13/cast v1.3.1
 	go.uber.org/goleak v0.10.0
 	golang.org/x/sys v0.0.0-20191204072324-ce4227a45e2e
--- a/go.sum
+++ b/go.sum
@@ -4,6 +4,8 @@ github.com/fsnotify/fsnotify v1.4.7 h1:IXs+QLmnXW2CcXuY+8Mzv/fWEsPGWxqefPtCP5CnV
 github.com/fsnotify/fsnotify v1.4.7/go.mod h1:jwhsz4b93w/PPRr/qN1Yymfu8t87LnFCMoQvtojpjFo=
 github.com/go-redis/redis/v7 v7.2.0 h1:CrCexy/jYWZjW0AyVoHlcJUeZN19VWlbepTh1Vq6dJs=
 github.com/go-redis/redis/v7 v7.2.0/go.mod h1:JDNMw23GTyLNC4GZu9njt15ctBQVn7xjRfnwdHj/Dcg=
+github.com/go-redis/redis/v7 v7.4.0 h1:7obg6wUoj05T0EpY0o8B59S9w5yeMWql7sw2kwNW1x4=
+github.com/go-redis/redis/v7 v7.4.0/go.mod h1:JDNMw23GTyLNC4GZu9njt15ctBQVn7xjRfnwdHj/Dcg=
 github.com/golang/protobuf v1.2.0/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
 github.com/golang/protobuf v1.3.2 h1:6nsPYzhq5kReh6QImI3k5qWzO4PEbvbIW2cwSfR/6xs=
 github.com/golang/protobuf v1.3.2/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
@@ -25,6 +27,8 @@ github.com/onsi/gomega v1.7.0 h1:XPnZz8VVBHjVsy1vzJmRwIcSwiUO+JFfrv/xGiigmME=
 github.com/onsi/gomega v1.7.0/go.mod h1:ex+gbHU/CVuBBDIJjb2X0qEXbFg53c61hWP/1CpauHY=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/robfig/cron/v3 v3.0.1 h1:WdRxkvbJztn8LMz/QEvLN5sBU+xKpSqwwUO1Pjr4qDs=
+github.com/robfig/cron/v3 v3.0.1/go.mod h1:eQICP3HwyT7UooqI/z+Ov+PtYAWygg1TEWWzGIFLtro=
 github.com/spf13/cast v1.3.1 h1:nFm6S0SMdyzrzcmThSipiEubIDy8WEXKNZ0UOgiRpng=
 github.com/spf13/cast v1.3.1/go.mod h1:Qx5cxh0v+4UWYiBimWS+eyWzqEqokIECu5etghLkUJE=
 github.com/stretchr/testify v1.2.2 h1:bSDNvY7ZPG5RlJ8otE/7V6gMiyenm9RtJ7IUVIAoJ1w=
--- a/healthcheck.go
+++ b/healthcheck.go
@@ -0,0 +1,80 @@
+// Copyright 2020 Kentaro Hibino. All rights reserved.
+// Use of this source code is governed by a MIT license
+// that can be found in the LICENSE file.
+
+package asynq
+
+import (
+	"sync"
+	"time"
+
+	"github.com/hibiken/asynq/internal/base"
+	"github.com/hibiken/asynq/internal/log"
+)
+
+// healthchecker is responsible for pinging broker periodically
+// and call user provided HeathCheckFunc with the ping result.
+type healthchecker struct {
+	logger *log.Logger
+	broker base.Broker
+
+	// channel to communicate back to the long running "healthchecker" goroutine.
+	done chan struct{}
+
+	// interval between healthchecks.
+	interval time.Duration
+
+	// function to call periodically.
+	healthcheckFunc func(error)
+}
+
+type healthcheckerParams struct {
+	logger          *log.Logger
+	broker          base.Broker
+	interval        time.Duration
+	healthcheckFunc func(error)
+}
+
+func newHealthChecker(params healthcheckerParams) *healthchecker {
+	return &healthchecker{
+		logger:          params.logger,
+		broker:          params.broker,
+		done:            make(chan struct{}),
+		interval:        params.interval,
+		healthcheckFunc: params.healthcheckFunc,
+	}
+}
+
+func (hc *healthchecker) terminate() {
+	if hc.healthcheckFunc == nil {
+		return
+	}
+
+	hc.logger.Debug("Healthchecker shutting down...")
+	// Signal the healthchecker goroutine to stop.
+	hc.done <- struct{}{}
+}
+
+func (hc *healthchecker) start(wg *sync.WaitGroup) {
+	if hc.healthcheckFunc == nil {
+		return
+	}
+
+	wg.Add(1)
+	go func() {
+		defer wg.Done()
+		timer := time.NewTimer(hc.interval)
+		for {
+			select {
+			case <-hc.done:
+				hc.logger.Debug("Healthchecker done")
+				timer.Stop()
+				return
+			case <-timer.C:
+				err := hc.broker.Ping()
+				hc.healthcheckFunc(err)
+				timer.Reset(hc.interval)
+			}
+		}
+	}()
+}
--- a/healthcheck_test.go
+++ b/healthcheck_test.go
@@ -0,0 +1,103 @@
+// Copyright 2020 Kentaro Hibino. All rights reserved.
+// Use of this source code is governed by a MIT license
+// that can be found in the LICENSE file.
+
+package asynq
+
+import (
+	"sync"
+	"testing"
+	"time"
+
+	"github.com/hibiken/asynq/internal/rdb"
+	"github.com/hibiken/asynq/internal/testbroker"
+)
+
+func TestHealthChecker(t *testing.T) {
+	r := setup(t)
+	defer r.Close()
+	rdbClient := rdb.NewRDB(r)
+
+	var (
+		// mu guards called and e variables.
+		mu     sync.Mutex
+		called int
+		e      error
+	)
+	checkFn := func(err error) {
+		mu.Lock()
+		defer mu.Unlock()
+		called++
+		e = err
+	}
+
+	hc := newHealthChecker(healthcheckerParams{
+		logger:          testLogger,
+		broker:          rdbClient,
+		interval:        1 * time.Second,
+		healthcheckFunc: checkFn,
+	})
+
+	hc.start(&sync.WaitGroup{})
+
+	time.Sleep(2 * time.Second)
+
+	mu.Lock()
+	if called == 0 {
+		t.Errorf("Healthchecker did not call the provided HealthCheckFunc")
+	}
+	if e != nil {
+		t.Errorf("HealthCheckFunc was called with non-nil error: %v", e)
+	}
+	mu.Unlock()
+
+	hc.terminate()
+}
+
+func TestHealthCheckerWhenRedisDown(t *testing.T) {
+	// Make sure that healthchecker goroutine doesn't panic
+	// if it cannot connect to redis.
+	defer func() {
+		if r := recover(); r != nil {
+			t.Errorf("panic occurred: %v", r)
+		}
+	}()
+	r := rdb.NewRDB(setup(t))
+	defer r.Close()
+	testBroker := testbroker.NewTestBroker(r)
+	var (
+		// mu guards called and e variables.
+		mu     sync.Mutex
+		called int
+		e      error
+	)
+	checkFn := func(err error) {
+		mu.Lock()
+		defer mu.Unlock()
+		called++
+		e = err
+	}
+
+	hc := newHealthChecker(healthcheckerParams{
+		logger:          testLogger,
+		broker:          testBroker,
+		interval:        1 * time.Second,
+		healthcheckFunc: checkFn,
+	})
+
+	testBroker.Sleep()
+	hc.start(&sync.WaitGroup{})
+
+	time.Sleep(2 * time.Second)
+
+	mu.Lock()
+	if called == 0 {
+		t.Errorf("Healthchecker did not call the provided HealthCheckFunc")
+	}
+	if e == nil {
+		t.Errorf("HealthCheckFunc was called with nil; want non-nil error")
+	}
+	mu.Unlock()
+
+	hc.terminate()
+}
--- a/heartbeat.go
+++ b/heartbeat.go
@@ -147,13 +147,14 @@ func (h *heartbeater) beat() {
 	var ws []*base.WorkerInfo
 	for id, stat := range h.workers {
 		ws = append(ws, &base.WorkerInfo{
-			Host:    h.host,
-			PID:     h.pid,
-			ID:      id,
-			Type:    stat.msg.Type,
-			Queue:   stat.msg.Queue,
-			Payload: stat.msg.Payload,
-			Started: stat.started,
+			Host:     h.host,
+			PID:      h.pid,
+			ServerID: h.serverID,
+			ID:       id,
+			Type:     stat.msg.Type,
+			Queue:    stat.msg.Queue,
+			Payload:  stat.msg.Payload,
+			Started:  stat.started,
 		})
 	}

--- a/heartbeat_test.go
+++ b/heartbeat_test.go
@@ -19,6 +19,7 @@ import (

 func TestHeartbeater(t *testing.T) {
 	r := setup(t)
+	defer r.Close()
 	rdbClient := rdb.NewRDB(r)

 	tests := []struct {
@@ -28,7 +29,7 @@ func TestHeartbeater(t *testing.T) {
 		queues      map[string]int
 		concurrency int
 	}{
-		{time.Second, "localhost", 45678, map[string]int{"default": 1}, 10},
+		{2 * time.Second, "localhost", 45678, map[string]int{"default": 1}, 10},
 	}

 	timeCmpOpt := cmpopts.EquateApproxTime(10 * time.Millisecond)
@@ -68,7 +69,7 @@ func TestHeartbeater(t *testing.T) {
 		}

 		// allow for heartbeater to write to redis
-		time.Sleep(tc.interval * 2)
+		time.Sleep(tc.interval)

 		ss, err := rdbClient.ListServers()
 		if err != nil {
@@ -128,6 +129,7 @@ func TestHeartbeaterWithRedisDown(t *testing.T) {
 		}
 	}()
 	r := rdb.NewRDB(setup(t))
+	defer r.Close()
 	testBroker := testbroker.NewTestBroker(r)
 	hb := newHeartbeater(heartbeaterParams{
 		logger:         testLogger,
--- a/inspector.go
+++ b/inspector.go
@@ -0,0 +1,809 @@
+// Copyright 2020 Kentaro Hibino. All rights reserved.
+// Use of this source code is governed by a MIT license
+// that can be found in the LICENSE file.
+
+package asynq
+
+import (
+	"fmt"
+	"strconv"
+	"strings"
+	"time"
+
+	"github.com/google/uuid"
+	"github.com/hibiken/asynq/internal/rdb"
+)
+
+// Inspector is a client interface to inspect and mutate the state of
+// queues and tasks.
+type Inspector struct {
+	rdb *rdb.RDB
+}
+
+// NewInspector returns a new instance of Inspector.
+func NewInspector(r RedisConnOpt) *Inspector {
+	return &Inspector{
+		rdb: rdb.NewRDB(createRedisClient(r)),
+	}
+}
+
+// Close closes the connection with redis.
+func (i *Inspector) Close() error {
+	return i.rdb.Close()
+}
+
+// Queues returns a list of all queue names.
+func (i *Inspector) Queues() ([]string, error) {
+	return i.rdb.AllQueues()
+}
+
+// QueueStats represents a state of queues at a certain time.
+type QueueStats struct {
+	// Name of the queue.
+	Queue string
+	// Size is the total number of tasks in the queue.
+	// The value is the sum of Pending, Active, Scheduled, Retry, and Archived.
+	Size int
+	// Number of pending tasks.
+	Pending int
+	// Number of active tasks.
+	Active int
+	// Number of scheduled tasks.
+	Scheduled int
+	// Number of retry tasks.
+	Retry int
+	// Number of archived tasks.
+	Archived int
+	// Total number of tasks being processed during the given date.
+	// The number includes both succeeded and failed tasks.
+	Processed int
+	// Total number of tasks failed to be processed during the given date.
+	Failed int
+	// Paused indicates whether the queue is paused.
+	// If true, tasks in the queue will not be processed.
+	Paused bool
+	// Time when this stats was taken.
+	Timestamp time.Time
+}
+
+// CurrentStats returns a current stats of the given queue.
+func (i *Inspector) CurrentStats(qname string) (*QueueStats, error) {
+	if err := validateQueueName(qname); err != nil {
+		return nil, err
+	}
+	stats, err := i.rdb.CurrentStats(qname)
+	if err != nil {
+		return nil, err
+	}
+	return &QueueStats{
+		Queue:     stats.Queue,
+		Size:      stats.Size,
+		Pending:   stats.Pending,
+		Active:    stats.Active,
+		Scheduled: stats.Scheduled,
+		Retry:     stats.Retry,
+		Archived:  stats.Archived,
+		Processed: stats.Processed,
+		Failed:    stats.Failed,
+		Paused:    stats.Paused,
+		Timestamp: stats.Timestamp,
+	}, nil
+}
+
+// DailyStats holds aggregate data for a given day for a given queue.
+type DailyStats struct {
+	// Name of the queue.
+	Queue string
+	// Total number of tasks being processed during the given date.
+	// The number includes both succeeded and failed tasks.
+	Processed int
+	// Total number of tasks failed to be processed during the given date.
+	Failed int
+	// Date this stats was taken.
+	Date time.Time
+}
+
+// History returns a list of stats from the last n days.
+func (i *Inspector) History(qname string, n int) ([]*DailyStats, error) {
+	if err := validateQueueName(qname); err != nil {
+		return nil, err
+	}
+	stats, err := i.rdb.HistoricalStats(qname, n)
+	if err != nil {
+		return nil, err
+	}
+	var res []*DailyStats
+	for _, s := range stats {
+		res = append(res, &DailyStats{
+			Queue:     s.Queue,
+			Processed: s.Processed,
+			Failed:    s.Failed,
+			Date:      s.Time,
+		})
+	}
+	return res, nil
+}
+
+// ErrQueueNotFound indicates that the specified queue does not exist.
+type ErrQueueNotFound struct {
+	qname string
+}
+
+func (e *ErrQueueNotFound) Error() string {
+	return fmt.Sprintf("queue %q does not exist", e.qname)
+}
+
+// ErrQueueNotEmpty indicates that the specified queue is not empty.
+type ErrQueueNotEmpty struct {
+	qname string
+}
+
+func (e *ErrQueueNotEmpty) Error() string {
+	return fmt.Sprintf("queue %q is not empty", e.qname)
+}
+
+// DeleteQueue removes the specified queue.
+//
+// If force is set to true, DeleteQueue will remove the queue regardless of
+// the queue size as long as no tasks are active in the queue.
+// If force is set to false, DeleteQueue will remove the queue only if
+// the queue is empty.
+//
+// If the specified queue does not exist, DeleteQueue returns ErrQueueNotFound.
+// If force is set to false and the specified queue is not empty, DeleteQueue
+// returns ErrQueueNotEmpty.
+func (i *Inspector) DeleteQueue(qname string, force bool) error {
+	err := i.rdb.RemoveQueue(qname, force)
+	if _, ok := err.(*rdb.ErrQueueNotFound); ok {
+		return &ErrQueueNotFound{qname}
+	}
+	if _, ok := err.(*rdb.ErrQueueNotEmpty); ok {
+		return &ErrQueueNotEmpty{qname}
+	}
+	return err
+}
+
+// PendingTask is a task in a queue and is ready to be processed.
+type PendingTask struct {
+	*Task
+	ID    string
+	Queue string
+}
+
+// ActiveTask is a task that's currently being processed.
+type ActiveTask struct {
+	*Task
+	ID    string
+	Queue string
+}
+
+// ScheduledTask is a task scheduled to be processed in the future.
+type ScheduledTask struct {
+	*Task
+	ID            string
+	Queue         string
+	NextProcessAt time.Time
+
+	score int64
+}
+
+// RetryTask is a task scheduled to be retried in the future.
+type RetryTask struct {
+	*Task
+	ID            string
+	Queue         string
+	NextProcessAt time.Time
+	MaxRetry      int
+	Retried       int
+	ErrorMsg      string
+	// TODO: LastFailedAt  time.Time
+
+	score int64
+}
+
+// ArchivedTask is a task archived for debugging and inspection purposes, and
+// it won't be retried automatically.
+// A task can be archived when the task exhausts its retry counts or manually
+// archived by a user via the CLI or Inspector.
+type ArchivedTask struct {
+	*Task
+	ID           string
+	Queue        string
+	MaxRetry     int
+	Retried      int
+	LastFailedAt time.Time
+	ErrorMsg     string
+
+	score int64
+}
+
+// Key returns a key used to delete, run, and archive the task.
+func (t *ScheduledTask) Key() string {
+	return fmt.Sprintf("s:%v:%v", t.ID, t.score)
+}
+
+// Key returns a key used to delete, run, and archive the task.
+func (t *RetryTask) Key() string {
+	return fmt.Sprintf("r:%v:%v", t.ID, t.score)
+}
+
+// Key returns a key used to delete, run, and archive the task.
+func (t *ArchivedTask) Key() string {
+	return fmt.Sprintf("a:%v:%v", t.ID, t.score)
+}
+
+// parseTaskKey parses a key string and returns each part of key with proper
+// type if valid, otherwise it reports an error.
+func parseTaskKey(key string) (id uuid.UUID, score int64, state string, err error) {
+	parts := strings.Split(key, ":")
+	if len(parts) != 3 {
+		return uuid.Nil, 0, "", fmt.Errorf("invalid id")
+	}
+	id, err = uuid.Parse(parts[1])
+	if err != nil {
+		return uuid.Nil, 0, "", fmt.Errorf("invalid id")
+	}
+	score, err = strconv.ParseInt(parts[2], 10, 64)
+	if err != nil {
+		return uuid.Nil, 0, "", fmt.Errorf("invalid id")
+	}
+	state = parts[0]
+	if len(state) != 1 || !strings.Contains("sra", state) {
+		return uuid.Nil, 0, "", fmt.Errorf("invalid id")
+	}
+	return id, score, state, nil
+}
+
+// ListOption specifies behavior of list operation.
+type ListOption interface{}
+
+// Internal list option representations.
+type (
+	pageSizeOpt int
+	pageNumOpt  int
+)
+
+type listOption struct {
+	pageSize int
+	pageNum  int
+}
+
+const (
+	// Page size used by default in list operation.
+	defaultPageSize = 30
+
+	// Page number used by default in list operation.
+	defaultPageNum = 1
+)
+
+func composeListOptions(opts ...ListOption) listOption {
+	res := listOption{
+		pageSize: defaultPageSize,
+		pageNum:  defaultPageNum,
+	}
+	for _, opt := range opts {
+		switch opt := opt.(type) {
+		case pageSizeOpt:
+			res.pageSize = int(opt)
+		case pageNumOpt:
+			res.pageNum = int(opt)
+		default:
+			// ignore unexpected option
+		}
+	}
+	return res
+}
+
+// PageSize returns an option to specify the page size for list operation.
+//
+// Negative page size is treated as zero.
+func PageSize(n int) ListOption {
+	if n < 0 {
+		n = 0
+	}
+	return pageSizeOpt(n)
+}
+
+// Page returns an option to specify the page number for list operation.
+// The value 1 fetches the first page.
+//
+// Negative page number is treated as one.
+func Page(n int) ListOption {
+	if n < 0 {
+		n = 1
+	}
+	return pageNumOpt(n)
+}
+
+// ListPendingTasks retrieves pending tasks from the specified queue.
+//
+// By default, it retrieves the first 30 tasks.
+func (i *Inspector) ListPendingTasks(qname string, opts ...ListOption) ([]*PendingTask, error) {
+	if err := validateQueueName(qname); err != nil {
+		return nil, err
+	}
+	opt := composeListOptions(opts...)
+	pgn := rdb.Pagination{Size: opt.pageSize, Page: opt.pageNum - 1}
+	msgs, err := i.rdb.ListPending(qname, pgn)
+	if err != nil {
+		return nil, err
+	}
+	var tasks []*PendingTask
+	for _, m := range msgs {
+		tasks = append(tasks, &PendingTask{
+			Task:  NewTask(m.Type, m.Payload),
+			ID:    m.ID.String(),
+			Queue: m.Queue,
+		})
+	}
+	return tasks, err
+}
+
+// ListActiveTasks retrieves active tasks from the specified queue.
+//
+// By default, it retrieves the first 30 tasks.
+func (i *Inspector) ListActiveTasks(qname string, opts ...ListOption) ([]*ActiveTask, error) {
+	if err := validateQueueName(qname); err != nil {
+		return nil, err
+	}
+	opt := composeListOptions(opts...)
+	pgn := rdb.Pagination{Size: opt.pageSize, Page: opt.pageNum - 1}
+	msgs, err := i.rdb.ListActive(qname, pgn)
+	if err != nil {
+		return nil, err
+	}
+	var tasks []*ActiveTask
+	for _, m := range msgs {
+		tasks = append(tasks, &ActiveTask{
+			Task:  NewTask(m.Type, m.Payload),
+			ID:    m.ID.String(),
+			Queue: m.Queue,
+		})
+	}
+	return tasks, err
+}
+
+// ListScheduledTasks retrieves scheduled tasks from the specified queue.
+// Tasks are sorted by NextProcessAt field in ascending order.
+//
+// By default, it retrieves the first 30 tasks.
+func (i *Inspector) ListScheduledTasks(qname string, opts ...ListOption) ([]*ScheduledTask, error) {
+	if err := validateQueueName(qname); err != nil {
+		return nil, err
+	}
+	opt := composeListOptions(opts...)
+	pgn := rdb.Pagination{Size: opt.pageSize, Page: opt.pageNum - 1}
+	zs, err := i.rdb.ListScheduled(qname, pgn)
+	if err != nil {
+		return nil, err
+	}
+	var tasks []*ScheduledTask
+	for _, z := range zs {
+		processAt := time.Unix(z.Score, 0)
+		t := NewTask(z.Message.Type, z.Message.Payload)
+		tasks = append(tasks, &ScheduledTask{
+			Task:          t,
+			ID:            z.Message.ID.String(),
+			Queue:         z.Message.Queue,
+			NextProcessAt: processAt,
+			score:         z.Score,
+		})
+	}
+	return tasks, nil
+}
+
+// ListRetryTasks retrieves retry tasks from the specified queue.
+// Tasks are sorted by NextProcessAt field in ascending order.
+//
+// By default, it retrieves the first 30 tasks.
+func (i *Inspector) ListRetryTasks(qname string, opts ...ListOption) ([]*RetryTask, error) {
+	if err := validateQueueName(qname); err != nil {
+		return nil, err
+	}
+	opt := composeListOptions(opts...)
+	pgn := rdb.Pagination{Size: opt.pageSize, Page: opt.pageNum - 1}
+	zs, err := i.rdb.ListRetry(qname, pgn)
+	if err != nil {
+		return nil, err
+	}
+	var tasks []*RetryTask
+	for _, z := range zs {
+		processAt := time.Unix(z.Score, 0)
+		t := NewTask(z.Message.Type, z.Message.Payload)
+		tasks = append(tasks, &RetryTask{
+			Task:          t,
+			ID:            z.Message.ID.String(),
+			Queue:         z.Message.Queue,
+			NextProcessAt: processAt,
+			MaxRetry:      z.Message.Retry,
+			Retried:       z.Message.Retried,
+			// TODO: LastFailedAt: z.Message.LastFailedAt
+			ErrorMsg: z.Message.ErrorMsg,
+			score:    z.Score,
+		})
+	}
+	return tasks, nil
+}
+
+// ListArchivedTasks retrieves archived tasks from the specified queue.
+// Tasks are sorted by LastFailedAt field in descending order.
+//
+// By default, it retrieves the first 30 tasks.
+func (i *Inspector) ListArchivedTasks(qname string, opts ...ListOption) ([]*ArchivedTask, error) {
+	if err := validateQueueName(qname); err != nil {
+		return nil, err
+	}
+	opt := composeListOptions(opts...)
+	pgn := rdb.Pagination{Size: opt.pageSize, Page: opt.pageNum - 1}
+	zs, err := i.rdb.ListArchived(qname, pgn)
+	if err != nil {
+		return nil, err
+	}
+	var tasks []*ArchivedTask
+	for _, z := range zs {
+		failedAt := time.Unix(z.Score, 0)
+		t := NewTask(z.Message.Type, z.Message.Payload)
+		tasks = append(tasks, &ArchivedTask{
+			Task:         t,
+			ID:           z.Message.ID.String(),
+			Queue:        z.Message.Queue,
+			MaxRetry:     z.Message.Retry,
+			Retried:      z.Message.Retried,
+			LastFailedAt: failedAt,
+			ErrorMsg:     z.Message.ErrorMsg,
+			score:        z.Score,
+		})
+	}
+	return tasks, nil
+}
+
+// DeleteAllScheduledTasks deletes all scheduled tasks from the specified queue,
+// and reports the number tasks deleted.
+func (i *Inspector) DeleteAllScheduledTasks(qname string) (int, error) {
+	if err := validateQueueName(qname); err != nil {
+		return 0, err
+	}
+	n, err := i.rdb.DeleteAllScheduledTasks(qname)
+	return int(n), err
+}
+
+// DeleteAllRetryTasks deletes all retry tasks from the specified queue,
+// and reports the number tasks deleted.
+func (i *Inspector) DeleteAllRetryTasks(qname string) (int, error) {
+	if err := validateQueueName(qname); err != nil {
+		return 0, err
+	}
+	n, err := i.rdb.DeleteAllRetryTasks(qname)
+	return int(n), err
+}
+
+// DeleteAllArchivedTasks deletes all archived tasks from the specified queue,
+// and reports the number tasks deleted.
+func (i *Inspector) DeleteAllArchivedTasks(qname string) (int, error) {
+	if err := validateQueueName(qname); err != nil {
+		return 0, err
+	}
+	n, err := i.rdb.DeleteAllArchivedTasks(qname)
+	return int(n), err
+}
+
+// DeleteTaskByKey deletes a task with the given key from the given queue.
+func (i *Inspector) DeleteTaskByKey(qname, key string) error {
+	if err := validateQueueName(qname); err != nil {
+		return err
+	}
+	id, score, state, err := parseTaskKey(key)
+	if err != nil {
+		return err
+	}
+	switch state {
+	case "s":
+		return i.rdb.DeleteScheduledTask(qname, id, score)
+	case "r":
+		return i.rdb.DeleteRetryTask(qname, id, score)
+	case "a":
+		return i.rdb.DeleteArchivedTask(qname, id, score)
+	default:
+		return fmt.Errorf("invalid key")
+	}
+}
+
+// RunAllScheduledTasks transition all scheduled tasks to pending state within the given queue,
+// and reports the number of tasks transitioned.
+func (i *Inspector) RunAllScheduledTasks(qname string) (int, error) {
+	if err := validateQueueName(qname); err != nil {
+		return 0, err
+	}
+	n, err := i.rdb.RunAllScheduledTasks(qname)
+	return int(n), err
+}
+
+// RunAllRetryTasks transition all retry tasks to pending state within the given queue,
+// and reports the number of tasks transitioned.
+func (i *Inspector) RunAllRetryTasks(qname string) (int, error) {
+	if err := validateQueueName(qname); err != nil {
+		return 0, err
+	}
+	n, err := i.rdb.RunAllRetryTasks(qname)
+	return int(n), err
+}
+
+// RunAllArchivedTasks transition all archived tasks to pending state within the given queue,
+// and reports the number of tasks transitioned.
+func (i *Inspector) RunAllArchivedTasks(qname string) (int, error) {
+	if err := validateQueueName(qname); err != nil {
+		return 0, err
+	}
+	n, err := i.rdb.RunAllArchivedTasks(qname)
+	return int(n), err
+}
+
+// RunTaskByKey transition a task to pending state given task key and queue name.
+func (i *Inspector) RunTaskByKey(qname, key string) error {
+	if err := validateQueueName(qname); err != nil {
+		return err
+	}
+	id, score, state, err := parseTaskKey(key)
+	if err != nil {
+		return err
+	}
+	switch state {
+	case "s":
+		return i.rdb.RunScheduledTask(qname, id, score)
+	case "r":
+		return i.rdb.RunRetryTask(qname, id, score)
+	case "a":
+		return i.rdb.RunArchivedTask(qname, id, score)
+	default:
+		return fmt.Errorf("invalid key")
+	}
+}
+
+// ArchiveAllScheduledTasks archives all scheduled tasks within the given queue,
+// and reports the number of tasks archiveed.
+func (i *Inspector) ArchiveAllScheduledTasks(qname string) (int, error) {
+	if err := validateQueueName(qname); err != nil {
+		return 0, err
+	}
+	n, err := i.rdb.ArchiveAllScheduledTasks(qname)
+	return int(n), err
+}
+
+// ArchiveAllRetryTasks archives all retry tasks within the given queue,
+// and reports the number of tasks archiveed.
+func (i *Inspector) ArchiveAllRetryTasks(qname string) (int, error) {
+	if err := validateQueueName(qname); err != nil {
+		return 0, err
+	}
+	n, err := i.rdb.ArchiveAllRetryTasks(qname)
+	return int(n), err
+}
+
+// ArchiveTaskByKey archives a task with the given key in the given queue.
+func (i *Inspector) ArchiveTaskByKey(qname, key string) error {
+	if err := validateQueueName(qname); err != nil {
+		return err
+	}
+	id, score, state, err := parseTaskKey(key)
+	if err != nil {
+		return err
+	}
+	switch state {
+	case "s":
+		return i.rdb.ArchiveScheduledTask(qname, id, score)
+	case "r":
+		return i.rdb.ArchiveRetryTask(qname, id, score)
+	case "a":
+		return fmt.Errorf("task already archived")
+	default:
+		return fmt.Errorf("invalid key")
+	}
+}
+
+// CancelActiveTask sends a signal to cancel processing of the task with
+// the given id. CancelActiveTask is best-effort, which means that it does not
+// guarantee that the task with the given id will be canceled. The return
+// value only indicates whether the cancelation signal has been sent.
+func (i *Inspector) CancelActiveTask(id string) error {
+	return i.rdb.PublishCancelation(id)
+}
+
+// PauseQueue pauses task processing on the specified queue.
+// If the queue is already paused, it will return a non-nil error.
+func (i *Inspector) PauseQueue(qname string) error {
+	if err := validateQueueName(qname); err != nil {
+		return err
+	}
+	return i.rdb.Pause(qname)
+}
+
+// UnpauseQueue resumes task processing on the specified queue.
+// If the queue is not paused, it will return a non-nil error.
+func (i *Inspector) UnpauseQueue(qname string) error {
+	if err := validateQueueName(qname); err != nil {
+		return err
+	}
+	return i.rdb.Unpause(qname)
+}
+
+// Servers return a list of running servers' information.
+func (i *Inspector) Servers() ([]*ServerInfo, error) {
+	servers, err := i.rdb.ListServers()
+	if err != nil {
+		return nil, err
+	}
+	workers, err := i.rdb.ListWorkers()
+	if err != nil {
+		return nil, err
+	}
+	m := make(map[string]*ServerInfo) // ServerInfo keyed by serverID
+	for _, s := range servers {
+		m[s.ServerID] = &ServerInfo{
+			ID:             s.ServerID,
+			Host:           s.Host,
+			PID:            s.PID,
+			Concurrency:    s.Concurrency,
+			Queues:         s.Queues,
+			StrictPriority: s.StrictPriority,
+			Started:        s.Started,
+			Status:         s.Status,
+			ActiveWorkers:  make([]*WorkerInfo, 0),
+		}
+	}
+	for _, w := range workers {
+		srvInfo, ok := m[w.ServerID]
+		if !ok {
+			continue
+		}
+		wrkInfo := &WorkerInfo{
+			Started: w.Started,
+			Task: &ActiveTask{
+				Task:  NewTask(w.Type, w.Payload),
+				ID:    w.ID,
+				Queue: w.Queue,
+			},
+		}
+		srvInfo.ActiveWorkers = append(srvInfo.ActiveWorkers, wrkInfo)
+	}
+	var out []*ServerInfo
+	for _, srvInfo := range m {
+		out = append(out, srvInfo)
+	}
+	return out, nil
+}
+
+// ServerInfo describes a running Server instance.
+type ServerInfo struct {
+	// Unique Identifier for the server.
+	ID string
+	// Host machine on which the server is running.
+	Host string
+	// PID of the process in which the server is running.
+	PID int
+
+	// Server configuration details.
+	// See Config doc for field descriptions.
+	Concurrency    int
+	Queues         map[string]int
+	StrictPriority bool
+
+	// Time the server started.
+	Started time.Time
+	// Status indicates the status of the server.
+	// TODO: Update comment with more details.
+	Status string
+	// A List of active workers currently processing tasks.
+	ActiveWorkers []*WorkerInfo
+}
+
+// WorkerInfo describes a running worker processing a task.
+type WorkerInfo struct {
+	// The task the worker is processing.
+	Task *ActiveTask
+	// Time the worker started processing the task.
+	Started time.Time
+}
+
+// ClusterKeySlot returns an integer identifying the hash slot the given queue hashes to.
+func (i *Inspector) ClusterKeySlot(qname string) (int64, error) {
+	return i.rdb.ClusterKeySlot(qname)
+}
+
+// ClusterNode describes a node in redis cluster.
+type ClusterNode struct {
+	// Node ID in the cluster.
+	ID string
+
+	// Address of the node.
+	Addr string
+}
+
+// ClusterNodes returns a list of nodes the given queue belongs to.
+func (i *Inspector) ClusterNodes(qname string) ([]ClusterNode, error) {
+	nodes, err := i.rdb.ClusterNodes(qname)
+	if err != nil {
+		return nil, err
+	}
+	var res []ClusterNode
+	for _, node := range nodes {
+		res = append(res, ClusterNode{ID: node.ID, Addr: node.Addr})
+	}
+	return res, nil
+}
+
+// SchedulerEntry holds information about a periodic task registered with a scheduler.
+type SchedulerEntry struct {
+	// Identifier of this entry.
+	ID string
+
+	// Spec describes the schedule of this entry.
+	Spec string
+
+	// Periodic Task registered for this entry.
+	Task *Task
+
+	// Opts is the options for the periodic task.
+	Opts []Option
+
+	// Next shows the next time the task will be enqueued.
+	Next time.Time
+
+	// Prev shows the last time the task was enqueued.
+	// Zero time if task was never enqueued.
+	Prev time.Time
+}
+
+// SchedulerEntries returns a list of all entries registered with
+// currently running schedulers.
+func (i *Inspector) SchedulerEntries() ([]*SchedulerEntry, error) {
+	var entries []*SchedulerEntry
+	res, err := i.rdb.ListSchedulerEntries()
+	if err != nil {
+		return nil, err
+	}
+	for _, e := range res {
+		task := NewTask(e.Type, e.Payload)
+		var opts []Option
+		for _, s := range e.Opts {
+			if o, err := parseOption(s); err == nil {
+				// ignore bad data
+				opts = append(opts, o)
+			}
+		}
+		entries = append(entries, &SchedulerEntry{
+			ID:   e.ID,
+			Spec: e.Spec,
+			Task: task,
+			Opts: opts,
+			Next: e.Next,
+			Prev: e.Prev,
+		})
+	}
+	return entries, nil
+}
+
+// SchedulerEnqueueEvent holds information about an enqueue event by a scheduler.
+type SchedulerEnqueueEvent struct {
+	// ID of the task that was enqueued.
+	TaskID string
+
+	// Time the task was enqueued.
+	EnqueuedAt time.Time
+}
+
+// ListSchedulerEnqueueEvents retrieves a list of enqueue events from the specified scheduler entry.
+//
+// By default, it retrieves the first 30 tasks.
+func (i *Inspector) ListSchedulerEnqueueEvents(entryID string, opts ...ListOption) ([]*SchedulerEnqueueEvent, error) {
+	opt := composeListOptions(opts...)
+	pgn := rdb.Pagination{Size: opt.pageSize, Page: opt.pageNum - 1}
+	data, err := i.rdb.ListSchedulerEnqueueEvents(entryID, pgn)
+	if err != nil {
+		return nil, err
+	}
+	var events []*SchedulerEnqueueEvent
+	for _, e := range data {
+		events = append(events, &SchedulerEnqueueEvent{TaskID: e.TaskID, EnqueuedAt: e.EnqueuedAt})
+	}
+	return events, nil
+}
--- a/inspector_test.go
+++ b/inspector_test.go
--- a/internal/asynqtest/asynqtest.go
+++ b/internal/asynqtest/asynqtest.go
@@ -7,6 +7,7 @@ package asynqtest

 import (
 	"encoding/json"
+	"math"
 	"sort"
 	"testing"

@@ -17,10 +18,12 @@ import (
 	"github.com/hibiken/asynq/internal/base"
 )

-// ZSetEntry is an entry in redis sorted set.
-type ZSetEntry struct {
-	Msg   *base.TaskMessage
-	Score float64
+// EquateInt64Approx returns a Comparer option that treats int64 values
+// to be equal if they are within the given margin.
+func EquateInt64Approx(margin int64) cmp.Option {
+	return cmp.Comparer(func(a, b int64) bool {
+		return math.Abs(float64(a-b)) <= float64(margin)
+	})
 }

 // SortMsgOpt is a cmp.Option to sort base.TaskMessage for comparing slice of task messages.
@@ -33,10 +36,10 @@ var SortMsgOpt = cmp.Transformer("SortTaskMessages", func(in []*base.TaskMessage
 })

 // SortZSetEntryOpt is an cmp.Option to sort ZSetEntry for comparing slice of zset entries.
-var SortZSetEntryOpt = cmp.Transformer("SortZSetEntries", func(in []ZSetEntry) []ZSetEntry {
-	out := append([]ZSetEntry(nil), in...) // Copy input to avoid mutating it
+var SortZSetEntryOpt = cmp.Transformer("SortZSetEntries", func(in []base.Z) []base.Z {
+	out := append([]base.Z(nil), in...) // Copy input to avoid mutating it
 	sort.Slice(out, func(i, j int) bool {
-		return out[i].Msg.ID.String() < out[j].Msg.ID.String()
+		return out[i].Message.ID.String() < out[j].Message.ID.String()
 	})
 	return out
 })
@@ -62,6 +65,24 @@ var SortWorkerInfoOpt = cmp.Transformer("SortWorkerInfo", func(in []*base.Worker
 	return out
 })

+// SortSchedulerEntryOpt is a cmp.Option to sort base.SchedulerEntry for comparing slice of entries.
+var SortSchedulerEntryOpt = cmp.Transformer("SortSchedulerEntry", func(in []*base.SchedulerEntry) []*base.SchedulerEntry {
+	out := append([]*base.SchedulerEntry(nil), in...) // Copy input to avoid mutating it
+	sort.Slice(out, func(i, j int) bool {
+		return out[i].Spec < out[j].Spec
+	})
+	return out
+})
+
+// SortSchedulerEnqueueEventOpt is a cmp.Option to sort base.SchedulerEnqueueEvent for comparing slice of events.
+var SortSchedulerEnqueueEventOpt = cmp.Transformer("SortSchedulerEnqueueEvent", func(in []*base.SchedulerEnqueueEvent) []*base.SchedulerEnqueueEvent {
+	out := append([]*base.SchedulerEnqueueEvent(nil), in...)
+	sort.Slice(out, func(i, j int) bool {
+		return out[i].EnqueuedAt.Unix() < out[j].EnqueuedAt.Unix()
+	})
+	return out
+})
+
 // SortStringSliceOpt is a cmp.Option to sort string slice.
 var SortStringSliceOpt = cmp.Transformer("SortStringSlice", func(in []string) []string {
 	out := append([]string(nil), in...)
@@ -74,26 +95,20 @@ var IgnoreIDOpt = cmpopts.IgnoreFields(base.TaskMessage{}, "ID")

 // NewTaskMessage returns a new instance of TaskMessage given a task type and payload.
 func NewTaskMessage(taskType string, payload map[string]interface{}) *base.TaskMessage {
-	return &base.TaskMessage{
-		ID:       uuid.New(),
-		Type:     taskType,
-		Queue:    base.DefaultQueueName,
-		Retry:    25,
-		Payload:  payload,
-		Timeout:  1800, // default timeout of 30 mins
-		Deadline: 0,    // no deadline
-	}
+	return NewTaskMessageWithQueue(taskType, payload, base.DefaultQueueName)
 }

 // NewTaskMessageWithQueue returns a new instance of TaskMessage given a
 // task type, payload and queue name.
 func NewTaskMessageWithQueue(taskType string, payload map[string]interface{}, qname string) *base.TaskMessage {
 	return &base.TaskMessage{
-		ID:      uuid.New(),
-		Type:    taskType,
-		Queue:   qname,
-		Retry:   25,
-		Payload: payload,
+		ID:       uuid.New(),
+		Type:     taskType,
+		Queue:    qname,
+		Retry:    25,
+		Payload:  payload,
+		Timeout:  1800, // default timeout of 30 mins
+		Deadline: 0,    // no deadline
 	}
 }

@@ -157,57 +172,113 @@ func MustUnmarshalSlice(tb testing.TB, data []string) []*base.TaskMessage {
 }

 // FlushDB deletes all the keys of the currently selected DB.
-func FlushDB(tb testing.TB, r *redis.Client) {
+func FlushDB(tb testing.TB, r redis.UniversalClient) {
 	tb.Helper()
-	if err := r.FlushDB().Err(); err != nil {
-		tb.Fatal(err)
+	switch r := r.(type) {
+	case *redis.Client:
+		if err := r.FlushDB().Err(); err != nil {
+			tb.Fatal(err)
+		}
+	case *redis.ClusterClient:
+		err := r.ForEachMaster(func(c *redis.Client) error {
+			if err := c.FlushAll().Err(); err != nil {
+				return err
+			}
+			return nil
+		})
+		if err != nil {
+			tb.Fatal(err)
+		}
 	}
 }

-// SeedEnqueuedQueue initializes the specified queue with the given messages.
-//
-// If queue name option is not passed, it defaults to the default queue.
-func SeedEnqueuedQueue(tb testing.TB, r *redis.Client, msgs []*base.TaskMessage, queueOpt ...string) {
+// SeedPendingQueue initializes the specified queue with the given messages.
+func SeedPendingQueue(tb testing.TB, r redis.UniversalClient, msgs []*base.TaskMessage, qname string) {
 	tb.Helper()
-	queue := base.DefaultQueue
-	if len(queueOpt) > 0 {
-		queue = base.QueueKey(queueOpt[0])
-	}
-	r.SAdd(base.AllQueues, queue)
-	seedRedisList(tb, r, queue, msgs)
+	r.SAdd(base.AllQueues, qname)
+	seedRedisList(tb, r, base.QueueKey(qname), msgs)
 }

-// SeedInProgressQueue initializes the in-progress queue with the given messages.
-func SeedInProgressQueue(tb testing.TB, r *redis.Client, msgs []*base.TaskMessage) {
+// SeedActiveQueue initializes the active queue with the given messages.
+func SeedActiveQueue(tb testing.TB, r redis.UniversalClient, msgs []*base.TaskMessage, qname string) {
 	tb.Helper()
-	seedRedisList(tb, r, base.InProgressQueue, msgs)
+	r.SAdd(base.AllQueues, qname)
+	seedRedisList(tb, r, base.ActiveKey(qname), msgs)
 }

 // SeedScheduledQueue initializes the scheduled queue with the given messages.
-func SeedScheduledQueue(tb testing.TB, r *redis.Client, entries []ZSetEntry) {
+func SeedScheduledQueue(tb testing.TB, r redis.UniversalClient, entries []base.Z, qname string) {
 	tb.Helper()
-	seedRedisZSet(tb, r, base.ScheduledQueue, entries)
+	r.SAdd(base.AllQueues, qname)
+	seedRedisZSet(tb, r, base.ScheduledKey(qname), entries)
 }

 // SeedRetryQueue initializes the retry queue with the given messages.
-func SeedRetryQueue(tb testing.TB, r *redis.Client, entries []ZSetEntry) {
+func SeedRetryQueue(tb testing.TB, r redis.UniversalClient, entries []base.Z, qname string) {
 	tb.Helper()
-	seedRedisZSet(tb, r, base.RetryQueue, entries)
+	r.SAdd(base.AllQueues, qname)
+	seedRedisZSet(tb, r, base.RetryKey(qname), entries)
 }

-// SeedDeadQueue initializes the dead queue with the given messages.
-func SeedDeadQueue(tb testing.TB, r *redis.Client, entries []ZSetEntry) {
+// SeedArchivedQueue initializes the archived queue with the given messages.
+func SeedArchivedQueue(tb testing.TB, r redis.UniversalClient, entries []base.Z, qname string) {
 	tb.Helper()
-	seedRedisZSet(tb, r, base.DeadQueue, entries)
+	r.SAdd(base.AllQueues, qname)
+	seedRedisZSet(tb, r, base.ArchivedKey(qname), entries)
 }

 // SeedDeadlines initializes the deadlines set with the given entries.
-func SeedDeadlines(tb testing.TB, r *redis.Client, entries []ZSetEntry) {
+func SeedDeadlines(tb testing.TB, r redis.UniversalClient, entries []base.Z, qname string) {
 	tb.Helper()
-	seedRedisZSet(tb, r, base.KeyDeadlines, entries)
+	r.SAdd(base.AllQueues, qname)
+	seedRedisZSet(tb, r, base.DeadlinesKey(qname), entries)
 }

-func seedRedisList(tb testing.TB, c *redis.Client, key string, msgs []*base.TaskMessage) {
+// SeedAllPendingQueues initializes all of the specified queues with the given messages.
+//
+// pending maps a queue name to a list of messages.
+func SeedAllPendingQueues(tb testing.TB, r redis.UniversalClient, pending map[string][]*base.TaskMessage) {
+	for q, msgs := range pending {
+		SeedPendingQueue(tb, r, msgs, q)
+	}
+}
+
+// SeedAllActiveQueues initializes all of the specified active queues with the given messages.
+func SeedAllActiveQueues(tb testing.TB, r redis.UniversalClient, active map[string][]*base.TaskMessage) {
+	for q, msgs := range active {
+		SeedActiveQueue(tb, r, msgs, q)
+	}
+}
+
+// SeedAllScheduledQueues initializes all of the specified scheduled queues with the given entries.
+func SeedAllScheduledQueues(tb testing.TB, r redis.UniversalClient, scheduled map[string][]base.Z) {
+	for q, entries := range scheduled {
+		SeedScheduledQueue(tb, r, entries, q)
+	}
+}
+
+// SeedAllRetryQueues initializes all of the specified retry queues with the given entries.
+func SeedAllRetryQueues(tb testing.TB, r redis.UniversalClient, retry map[string][]base.Z) {
+	for q, entries := range retry {
+		SeedRetryQueue(tb, r, entries, q)
+	}
+}
+
+// SeedAllArchivedQueues initializes all of the specified archived queues with the given entries.
+func SeedAllArchivedQueues(tb testing.TB, r redis.UniversalClient, archived map[string][]base.Z) {
+	for q, entries := range archived {
+		SeedArchivedQueue(tb, r, entries, q)
+	}
+}
+
+// SeedAllDeadlines initializes all of the deadlines with the given entries.
+func SeedAllDeadlines(tb testing.TB, r redis.UniversalClient, deadlines map[string][]base.Z) {
+	for q, entries := range deadlines {
+		SeedDeadlines(tb, r, entries, q)
+	}
+}
+
+func seedRedisList(tb testing.TB, c redis.UniversalClient, key string, msgs []*base.TaskMessage) {
 	data := MustMarshalSlice(tb, msgs)
 	for _, s := range data {
 		if err := c.LPush(key, s).Err(); err != nil {
@@ -216,92 +287,86 @@ func seedRedisList(tb testing.TB, c *redis.Client, key string, msgs []*base.Task
 	}
 }

-func seedRedisZSet(tb testing.TB, c *redis.Client, key string, items []ZSetEntry) {
+func seedRedisZSet(tb testing.TB, c redis.UniversalClient, key string, items []base.Z) {
 	for _, item := range items {
-		z := &redis.Z{Member: MustMarshal(tb, item.Msg), Score: float64(item.Score)}
+		z := &redis.Z{Member: MustMarshal(tb, item.Message), Score: float64(item.Score)}
 		if err := c.ZAdd(key, z).Err(); err != nil {
 			tb.Fatal(err)
 		}
 	}
 }

-// GetEnqueuedMessages returns all task messages in the specified queue.
-//
-// If queue name option is not passed, it defaults to the default queue.
-func GetEnqueuedMessages(tb testing.TB, r *redis.Client, queueOpt ...string) []*base.TaskMessage {
+// GetPendingMessages returns all pending messages in the given queue.
+func GetPendingMessages(tb testing.TB, r redis.UniversalClient, qname string) []*base.TaskMessage {
 	tb.Helper()
-	queue := base.DefaultQueue
-	if len(queueOpt) > 0 {
-		queue = base.QueueKey(queueOpt[0])
-	}
-	return getListMessages(tb, r, queue)
+	return getListMessages(tb, r, base.QueueKey(qname))
 }

-// GetInProgressMessages returns all task messages in the in-progress queue.
-func GetInProgressMessages(tb testing.TB, r *redis.Client) []*base.TaskMessage {
+// GetActiveMessages returns all active messages in the given queue.
+func GetActiveMessages(tb testing.TB, r redis.UniversalClient, qname string) []*base.TaskMessage {
 	tb.Helper()
-	return getListMessages(tb, r, base.InProgressQueue)
+	return getListMessages(tb, r, base.ActiveKey(qname))
 }

-// GetScheduledMessages returns all task messages in the scheduled queue.
-func GetScheduledMessages(tb testing.TB, r *redis.Client) []*base.TaskMessage {
+// GetScheduledMessages returns all scheduled task messages in the given queue.
+func GetScheduledMessages(tb testing.TB, r redis.UniversalClient, qname string) []*base.TaskMessage {
 	tb.Helper()
-	return getZSetMessages(tb, r, base.ScheduledQueue)
+	return getZSetMessages(tb, r, base.ScheduledKey(qname))
 }

-// GetRetryMessages returns all task messages in the retry queue.
-func GetRetryMessages(tb testing.TB, r *redis.Client) []*base.TaskMessage {
+// GetRetryMessages returns all retry messages in the given queue.
+func GetRetryMessages(tb testing.TB, r redis.UniversalClient, qname string) []*base.TaskMessage {
 	tb.Helper()
-	return getZSetMessages(tb, r, base.RetryQueue)
+	return getZSetMessages(tb, r, base.RetryKey(qname))
 }

-// GetDeadMessages returns all task messages in the dead queue.
-func GetDeadMessages(tb testing.TB, r *redis.Client) []*base.TaskMessage {
+// GetArchivedMessages returns all archived messages in the given queue.
+func GetArchivedMessages(tb testing.TB, r redis.UniversalClient, qname string) []*base.TaskMessage {
 	tb.Helper()
-	return getZSetMessages(tb, r, base.DeadQueue)
+	return getZSetMessages(tb, r, base.ArchivedKey(qname))
 }

-// GetScheduledEntries returns all task messages and its score in the scheduled queue.
-func GetScheduledEntries(tb testing.TB, r *redis.Client) []ZSetEntry {
+// GetScheduledEntries returns all scheduled messages and its score in the given queue.
+func GetScheduledEntries(tb testing.TB, r redis.UniversalClient, qname string) []base.Z {
 	tb.Helper()
-	return getZSetEntries(tb, r, base.ScheduledQueue)
+	return getZSetEntries(tb, r, base.ScheduledKey(qname))
 }

-// GetRetryEntries returns all task messages and its score in the retry queue.
-func GetRetryEntries(tb testing.TB, r *redis.Client) []ZSetEntry {
+// GetRetryEntries returns all retry messages and its score in the given queue.
+func GetRetryEntries(tb testing.TB, r redis.UniversalClient, qname string) []base.Z {
 	tb.Helper()
-	return getZSetEntries(tb, r, base.RetryQueue)
+	return getZSetEntries(tb, r, base.RetryKey(qname))
 }

-// GetDeadEntries returns all task messages and its score in the dead queue.
-func GetDeadEntries(tb testing.TB, r *redis.Client) []ZSetEntry {
+// GetArchivedEntries returns all archived messages and its score in the given queue.
+func GetArchivedEntries(tb testing.TB, r redis.UniversalClient, qname string) []base.Z {
 	tb.Helper()
-	return getZSetEntries(tb, r, base.DeadQueue)
+	return getZSetEntries(tb, r, base.ArchivedKey(qname))
 }

-// GetDeadlinesEntries returns all task messages and its score in the deadlines set.
-func GetDeadlinesEntries(tb testing.TB, r *redis.Client) []ZSetEntry {
+// GetDeadlinesEntries returns all task messages and its score in the deadlines set for the given queue.
+func GetDeadlinesEntries(tb testing.TB, r redis.UniversalClient, qname string) []base.Z {
 	tb.Helper()
-	return getZSetEntries(tb, r, base.KeyDeadlines)
+	return getZSetEntries(tb, r, base.DeadlinesKey(qname))
 }

-func getListMessages(tb testing.TB, r *redis.Client, list string) []*base.TaskMessage {
+func getListMessages(tb testing.TB, r redis.UniversalClient, list string) []*base.TaskMessage {
 	data := r.LRange(list, 0, -1).Val()
 	return MustUnmarshalSlice(tb, data)
 }

-func getZSetMessages(tb testing.TB, r *redis.Client, zset string) []*base.TaskMessage {
+func getZSetMessages(tb testing.TB, r redis.UniversalClient, zset string) []*base.TaskMessage {
 	data := r.ZRange(zset, 0, -1).Val()
 	return MustUnmarshalSlice(tb, data)
 }

-func getZSetEntries(tb testing.TB, r *redis.Client, zset string) []ZSetEntry {
+func getZSetEntries(tb testing.TB, r redis.UniversalClient, zset string) []base.Z {
 	data := r.ZRangeWithScores(zset, 0, -1).Val()
-	var entries []ZSetEntry
+	var entries []base.Z
 	for _, z := range data {
-		entries = append(entries, ZSetEntry{
-			Msg:   MustUnmarshal(tb, z.Member.(string)),
-			Score: z.Score,
+		entries = append(entries, base.Z{
+			Message: MustUnmarshal(tb, z.Member.(string)),
+			Score:   int64(z.Score),
 		})
 	}
 	return entries
--- a/internal/base/base.go
+++ b/internal/base/base.go
@@ -9,6 +9,7 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
+	"sort"
 	"strings"
 	"sync"
 	"time"
@@ -18,54 +19,115 @@ import (
 )

 // Version of asynq library and CLI.
-const Version = "0.10.0"
+const Version = "0.14.0"

 // DefaultQueueName is the queue name used if none are specified by user.
 const DefaultQueueName = "default"

-// Redis keys
+// DefaultQueue is the redis key for the default queue.
+var DefaultQueue = QueueKey(DefaultQueueName)
+
+// Global Redis keys.
 const (
-	AllServers      = "asynq:servers"                // ZSET
-	serversPrefix   = "asynq:servers:"               // STRING - asynq:ps:<host>:<pid>:<serverid>
-	AllWorkers      = "asynq:workers"                // ZSET
-	workersPrefix   = "asynq:workers:"               // HASH   - asynq:workers:<host:<pid>:<serverid>
-	processedPrefix = "asynq:processed:"             // STRING - asynq:processed:<yyyy-mm-dd>
-	failurePrefix   = "asynq:failure:"               // STRING - asynq:failure:<yyyy-mm-dd>
-	QueuePrefix     = "asynq:queues:"                // LIST   - asynq:queues:<qname>
-	AllQueues       = "asynq:queues"                 // SET
-	DefaultQueue    = QueuePrefix + DefaultQueueName // LIST
-	ScheduledQueue  = "asynq:scheduled"              // ZSET
-	RetryQueue      = "asynq:retry"                  // ZSET
-	DeadQueue       = "asynq:dead"                   // ZSET
-	InProgressQueue = "asynq:in_progress"            // LIST
-	KeyDeadlines    = "asynq:deadlines"              // ZSET
-	PausedQueues    = "asynq:paused"                 // SET
-	CancelChannel   = "asynq:cancel"                 // PubSub channel
+	AllServers    = "asynq:servers"    // ZSET
+	AllWorkers    = "asynq:workers"    // ZSET
+	AllSchedulers = "asynq:schedulers" // ZSET
+	AllQueues     = "asynq:queues"     // SET
+	CancelChannel = "asynq:cancel"     // PubSub channel
 )

 // QueueKey returns a redis key for the given queue name.
 func QueueKey(qname string) string {
-	return QueuePrefix + strings.ToLower(qname)
+	return fmt.Sprintf("asynq:{%s}", qname)
 }

-// ProcessedKey returns a redis key for processed count for the given day.
-func ProcessedKey(t time.Time) string {
-	return processedPrefix + t.UTC().Format("2006-01-02")
+// ActiveKey returns a redis key for the active tasks.
+func ActiveKey(qname string) string {
+	return fmt.Sprintf("asynq:{%s}:active", qname)
 }

-// FailureKey returns a redis key for failure count for the given day.
-func FailureKey(t time.Time) string {
-	return failurePrefix + t.UTC().Format("2006-01-02")
+// ScheduledKey returns a redis key for the scheduled tasks.
+func ScheduledKey(qname string) string {
+	return fmt.Sprintf("asynq:{%s}:scheduled", qname)
+}
+
+// RetryKey returns a redis key for the retry tasks.
+func RetryKey(qname string) string {
+	return fmt.Sprintf("asynq:{%s}:retry", qname)
+}
+
+// ArchivedKey returns a redis key for the archived tasks.
+func ArchivedKey(qname string) string {
+	return fmt.Sprintf("asynq:{%s}:archived", qname)
+}
+
+// DeadlinesKey returns a redis key for the deadlines.
+func DeadlinesKey(qname string) string {
+	return fmt.Sprintf("asynq:{%s}:deadlines", qname)
+}
+
+// PausedKey returns a redis key to indicate that the given queue is paused.
+func PausedKey(qname string) string {
+	return fmt.Sprintf("asynq:{%s}:paused", qname)
+}
+
+// ProcessedKey returns a redis key for processed count for the given day for the queue.
+func ProcessedKey(qname string, t time.Time) string {
+	return fmt.Sprintf("asynq:{%s}:processed:%s", qname, t.UTC().Format("2006-01-02"))
+}
+
+// FailedKey returns a redis key for failure count for the given day for the queue.
+func FailedKey(qname string, t time.Time) string {
+	return fmt.Sprintf("asynq:{%s}:failed:%s", qname, t.UTC().Format("2006-01-02"))
 }

 // ServerInfoKey returns a redis key for process info.
-func ServerInfoKey(hostname string, pid int, sid string) string {
-	return fmt.Sprintf("%s%s:%d:%s", serversPrefix, hostname, pid, sid)
+func ServerInfoKey(hostname string, pid int, serverID string) string {
+	return fmt.Sprintf("asynq:servers:{%s:%d:%s}", hostname, pid, serverID)
 }

 // WorkersKey returns a redis key for the workers given hostname, pid, and server ID.
-func WorkersKey(hostname string, pid int, sid string) string {
-	return fmt.Sprintf("%s%s:%d:%s", workersPrefix, hostname, pid, sid)
+func WorkersKey(hostname string, pid int, serverID string) string {
+	return fmt.Sprintf("asynq:workers:{%s:%d:%s}", hostname, pid, serverID)
+}
+
+// SchedulerEntriesKey returns a redis key for the scheduler entries given scheduler ID.
+func SchedulerEntriesKey(schedulerID string) string {
+	return fmt.Sprintf("asynq:schedulers:{%s}", schedulerID)
+}
+
+// SchedulerHistoryKey returns a redis key for the scheduler's history for the given entry.
+func SchedulerHistoryKey(entryID string) string {
+	return fmt.Sprintf("asynq:scheduler_history:%s", entryID)
+}
+
+// UniqueKey returns a redis key with the given type, payload, and queue name.
+func UniqueKey(qname, tasktype string, payload map[string]interface{}) string {
+	return fmt.Sprintf("asynq:{%s}:unique:%s:%s", qname, tasktype, serializePayload(payload))
+}
+
+func serializePayload(payload map[string]interface{}) string {
+	if payload == nil {
+		return "nil"
+	}
+	type entry struct {
+		k string
+		v interface{}
+	}
+	var es []entry
+	for k, v := range payload {
+		es = append(es, entry{k, v})
+	}
+	// sort entries by key
+	sort.Slice(es, func(i, j int) bool { return es[i].k < es[j].k })
+	var b strings.Builder
+	for _, e := range es {
+		if b.Len() > 0 {
+			b.WriteString(",")
+		}
+		b.WriteString(fmt.Sprintf("%s=%v", e.k, e.v))
+	}
+	return b.String()
 }

 // TaskMessage is the internal representation of a task with additional metadata fields.
@@ -94,7 +156,7 @@ type TaskMessage struct {

 	// Timeout specifies timeout in seconds.
 	// If task processing doesn't complete within the timeout, the task will be retried
-	// if retry count is remaining. Otherwise it will be moved to the dead queue.
+	// if retry count is remaining. Otherwise it will be moved to the archive.
 	//
 	// Use zero to indicate no timeout.
 	Timeout int64
@@ -102,7 +164,7 @@ type TaskMessage struct {
 	// Deadline specifies the deadline for the task in Unix time,
 	// the number of seconds elapsed since January 1, 1970 UTC.
 	// If task processing doesn't complete before the deadline, the task will be retried
-	// if retry count is remaining. Otherwise it will be moved to the dead queue.
+	// if retry count is remaining. Otherwise it will be moved to the archive.
 	//
 	// Use zero to indicate no deadline.
 	Deadline int64
@@ -133,6 +195,12 @@ func DecodeMessage(s string) (*TaskMessage, error) {
 	return &msg, nil
 }

+// Z represents sorted set member.
+type Z struct {
+	Message *TaskMessage
+	Score   int64
+}
+
 // ServerStatus represents status of a server.
 // ServerStatus methods are concurrency safe.
 type ServerStatus struct {
@@ -151,10 +219,10 @@ const (
 	// StatusIdle indicates the server is in idle state.
 	StatusIdle ServerStatusValue = iota

-	// StatusRunning indicates the servier is up and processing tasks.
+	// StatusRunning indicates the server is up and active.
 	StatusRunning

-	// StatusQuiet indicates the server is up but not processing new tasks.
+	// StatusQuiet indicates the server is up but not active.
 	StatusQuiet

 	// StatusStopped indicates the server server has been stopped.
@@ -207,16 +275,51 @@ type ServerInfo struct {

 // WorkerInfo holds information about a running worker.
 type WorkerInfo struct {
-	Host    string
-	PID     int
-	ID      string
-	Type    string
-	Queue   string
-	Payload map[string]interface{}
-	Started time.Time
+	Host     string
+	PID      int
+	ServerID string
+	ID       string
+	Type     string
+	Queue    string
+	Payload  map[string]interface{}
+	Started  time.Time
 }

-// Cancelations is a collection that holds cancel functions for all in-progress tasks.
+// SchedulerEntry holds information about a periodic task registered with a scheduler.
+type SchedulerEntry struct {
+	// Identifier of this entry.
+	ID string
+
+	// Spec describes the schedule of this entry.
+	Spec string
+
+	// Type is the task type of the periodic task.
+	Type string
+
+	// Payload is the payload of the periodic task.
+	Payload map[string]interface{}
+
+	// Opts is the options for the periodic task.
+	Opts []string
+
+	// Next shows the next time the task will be enqueued.
+	Next time.Time
+
+	// Prev shows the last time the task was enqueued.
+	// Zero time if task was never enqueued.
+	Prev time.Time
+}
+
+// SchedulerEnqueueEvent holds information about an enqueue event by a scheduler.
+type SchedulerEnqueueEvent struct {
+	// ID of the task that was enqueued.
+	TaskID string
+
+	// Time the task was enqueued.
+	EnqueuedAt time.Time
+}
+
+// Cancelations is a collection that holds cancel functions for all active tasks.
 //
 // Cancelations are safe for concurrent use by multipel goroutines.
 type Cancelations struct {
@@ -257,6 +360,7 @@ func (c *Cancelations) Get(id string) (fn context.CancelFunc, ok bool) {
 //
 // See rdb.RDB as a reference implementation.
 type Broker interface {
+	Ping() error
 	Enqueue(msg *TaskMessage) error
 	EnqueueUnique(msg *TaskMessage, ttl time.Duration) error
 	Dequeue(qnames ...string) (*TaskMessage, time.Time, error)
@@ -265,9 +369,9 @@ type Broker interface {
 	Schedule(msg *TaskMessage, processAt time.Time) error
 	ScheduleUnique(msg *TaskMessage, processAt time.Time, ttl time.Duration) error
 	Retry(msg *TaskMessage, processAt time.Time, errMsg string) error
-	Kill(msg *TaskMessage, errMsg string) error
-	CheckAndEnqueue() error
-	ListDeadlineExceeded(deadline time.Time) ([]*TaskMessage, error)
+	Archive(msg *TaskMessage, errMsg string) error
+	CheckAndEnqueue(qnames ...string) error
+	ListDeadlineExceeded(deadline time.Time, qnames ...string) ([]*TaskMessage, error)
 	WriteServerState(info *ServerInfo, workers []*WorkerInfo, ttl time.Duration) error
 	ClearServerState(host string, pid int, serverID string) error
 	CancelationPubSub() (*redis.PubSub, error) // TODO: Need to decouple from redis to support other brokers
--- a/internal/base/base_test.go
+++ b/internal/base/base_test.go
@@ -20,7 +20,8 @@ func TestQueueKey(t *testing.T) {
 		qname string
 		want  string
 	}{
-		{"custom", "asynq:queues:custom"},
+		{"default", "asynq:{default}"},
+		{"custom", "asynq:{custom}"},
 	}

 	for _, tc := range tests {
@@ -31,36 +32,140 @@ func TestQueueKey(t *testing.T) {
 	}
 }

-func TestProcessedKey(t *testing.T) {
+func TestActiveKey(t *testing.T) {
 	tests := []struct {
-		input time.Time
+		qname string
 		want  string
 	}{
-		{time.Date(2019, 11, 14, 10, 30, 1, 1, time.UTC), "asynq:processed:2019-11-14"},
-		{time.Date(2020, 12, 1, 1, 0, 1, 1, time.UTC), "asynq:processed:2020-12-01"},
-		{time.Date(2020, 1, 6, 15, 02, 1, 1, time.UTC), "asynq:processed:2020-01-06"},
+		{"default", "asynq:{default}:active"},
+		{"custom", "asynq:{custom}:active"},
 	}

 	for _, tc := range tests {
-		got := ProcessedKey(tc.input)
+		got := ActiveKey(tc.qname)
+		if got != tc.want {
+			t.Errorf("ActiveKey(%q) = %q, want %q", tc.qname, got, tc.want)
+		}
+	}
+}
+
+func TestDeadlinesKey(t *testing.T) {
+	tests := []struct {
+		qname string
+		want  string
+	}{
+		{"default", "asynq:{default}:deadlines"},
+		{"custom", "asynq:{custom}:deadlines"},
+	}
+
+	for _, tc := range tests {
+		got := DeadlinesKey(tc.qname)
+		if got != tc.want {
+			t.Errorf("DeadlinesKey(%q) = %q, want %q", tc.qname, got, tc.want)
+		}
+	}
+}
+
+func TestScheduledKey(t *testing.T) {
+	tests := []struct {
+		qname string
+		want  string
+	}{
+		{"default", "asynq:{default}:scheduled"},
+		{"custom", "asynq:{custom}:scheduled"},
+	}
+
+	for _, tc := range tests {
+		got := ScheduledKey(tc.qname)
+		if got != tc.want {
+			t.Errorf("ScheduledKey(%q) = %q, want %q", tc.qname, got, tc.want)
+		}
+	}
+}
+
+func TestRetryKey(t *testing.T) {
+	tests := []struct {
+		qname string
+		want  string
+	}{
+		{"default", "asynq:{default}:retry"},
+		{"custom", "asynq:{custom}:retry"},
+	}
+
+	for _, tc := range tests {
+		got := RetryKey(tc.qname)
+		if got != tc.want {
+			t.Errorf("RetryKey(%q) = %q, want %q", tc.qname, got, tc.want)
+		}
+	}
+}
+
+func TestArchivedKey(t *testing.T) {
+	tests := []struct {
+		qname string
+		want  string
+	}{
+		{"default", "asynq:{default}:archived"},
+		{"custom", "asynq:{custom}:archived"},
+	}
+
+	for _, tc := range tests {
+		got := ArchivedKey(tc.qname)
+		if got != tc.want {
+			t.Errorf("ArchivedKey(%q) = %q, want %q", tc.qname, got, tc.want)
+		}
+	}
+}
+
+func TestPausedKey(t *testing.T) {
+	tests := []struct {
+		qname string
+		want  string
+	}{
+		{"default", "asynq:{default}:paused"},
+		{"custom", "asynq:{custom}:paused"},
+	}
+
+	for _, tc := range tests {
+		got := PausedKey(tc.qname)
+		if got != tc.want {
+			t.Errorf("PausedKey(%q) = %q, want %q", tc.qname, got, tc.want)
+		}
+	}
+}
+
+func TestProcessedKey(t *testing.T) {
+	tests := []struct {
+		qname string
+		input time.Time
+		want  string
+	}{
+		{"default", time.Date(2019, 11, 14, 10, 30, 1, 1, time.UTC), "asynq:{default}:processed:2019-11-14"},
+		{"critical", time.Date(2020, 12, 1, 1, 0, 1, 1, time.UTC), "asynq:{critical}:processed:2020-12-01"},
+		{"default", time.Date(2020, 1, 6, 15, 02, 1, 1, time.UTC), "asynq:{default}:processed:2020-01-06"},
+	}
+
+	for _, tc := range tests {
+		got := ProcessedKey(tc.qname, tc.input)
 		if got != tc.want {
 			t.Errorf("ProcessedKey(%v) = %q, want %q", tc.input, got, tc.want)
 		}
 	}
 }

-func TestFailureKey(t *testing.T) {
+func TestFailedKey(t *testing.T) {
 	tests := []struct {
+		qname string
 		input time.Time
 		want  string
 	}{
-		{time.Date(2019, 11, 14, 10, 30, 1, 1, time.UTC), "asynq:failure:2019-11-14"},
-		{time.Date(2020, 12, 1, 1, 0, 1, 1, time.UTC), "asynq:failure:2020-12-01"},
-		{time.Date(2020, 1, 6, 15, 02, 1, 1, time.UTC), "asynq:failure:2020-01-06"},
+		{"default", time.Date(2019, 11, 14, 10, 30, 1, 1, time.UTC), "asynq:{default}:failed:2019-11-14"},
+		{"custom", time.Date(2020, 12, 1, 1, 0, 1, 1, time.UTC), "asynq:{custom}:failed:2020-12-01"},
+		{"low", time.Date(2020, 1, 6, 15, 02, 1, 1, time.UTC), "asynq:{low}:failed:2020-01-06"},
 	}

 	for _, tc := range tests {
-		got := FailureKey(tc.input)
+		got := FailedKey(tc.qname, tc.input)
 		if got != tc.want {
 			t.Errorf("FailureKey(%v) = %q, want %q", tc.input, got, tc.want)
 		}
@@ -74,8 +179,8 @@ func TestServerInfoKey(t *testing.T) {
 		sid      string
 		want     string
 	}{
-		{"localhost", 9876, "server123", "asynq:servers:localhost:9876:server123"},
-		{"127.0.0.1", 1234, "server987", "asynq:servers:127.0.0.1:1234:server987"},
+		{"localhost", 9876, "server123", "asynq:servers:{localhost:9876:server123}"},
+		{"127.0.0.1", 1234, "server987", "asynq:servers:{127.0.0.1:1234:server987}"},
 	}

 	for _, tc := range tests {
@@ -94,8 +199,8 @@ func TestWorkersKey(t *testing.T) {
 		sid      string
 		want     string
 	}{
-		{"localhost", 9876, "server1", "asynq:workers:localhost:9876:server1"},
-		{"127.0.0.1", 1234, "server2", "asynq:workers:127.0.0.1:1234:server2"},
+		{"localhost", 9876, "server1", "asynq:workers:{localhost:9876:server1}"},
+		{"127.0.0.1", 1234, "server2", "asynq:workers:{127.0.0.1:1234:server2}"},
 	}

 	for _, tc := range tests {
@@ -107,6 +212,98 @@ func TestWorkersKey(t *testing.T) {
 	}
 }

+func TestSchedulerEntriesKey(t *testing.T) {
+	tests := []struct {
+		schedulerID string
+		want        string
+	}{
+		{"localhost:9876:scheduler123", "asynq:schedulers:{localhost:9876:scheduler123}"},
+		{"127.0.0.1:1234:scheduler987", "asynq:schedulers:{127.0.0.1:1234:scheduler987}"},
+	}
+
+	for _, tc := range tests {
+		got := SchedulerEntriesKey(tc.schedulerID)
+		if got != tc.want {
+			t.Errorf("SchedulerEntriesKey(%q) = %q, want %q", tc.schedulerID, got, tc.want)
+		}
+	}
+}
+
+func TestSchedulerHistoryKey(t *testing.T) {
+	tests := []struct {
+		entryID string
+		want    string
+	}{
+		{"entry876", "asynq:scheduler_history:entry876"},
+		{"entry345", "asynq:scheduler_history:entry345"},
+	}
+
+	for _, tc := range tests {
+		got := SchedulerHistoryKey(tc.entryID)
+		if got != tc.want {
+			t.Errorf("SchedulerHistoryKey(%q) = %q, want %q",
+				tc.entryID, got, tc.want)
+		}
+	}
+}
+
+func TestUniqueKey(t *testing.T) {
+	tests := []struct {
+		desc     string
+		qname    string
+		tasktype string
+		payload  map[string]interface{}
+		want     string
+	}{
+		{
+			"with primitive types",
+			"default",
+			"email:send",
+			map[string]interface{}{"a": 123, "b": "hello", "c": true},
+			"asynq:{default}:unique:email:send:a=123,b=hello,c=true",
+		},
+		{
+			"with unsorted keys",
+			"default",
+			"email:send",
+			map[string]interface{}{"b": "hello", "c": true, "a": 123},
+			"asynq:{default}:unique:email:send:a=123,b=hello,c=true",
+		},
+		{
+			"with composite types",
+			"default",
+			"email:send",
+			map[string]interface{}{
+				"address": map[string]string{"line": "123 Main St", "city": "Boston", "state": "MA"},
+				"names":   []string{"bob", "mike", "rob"}},
+			"asynq:{default}:unique:email:send:address=map[city:Boston line:123 Main St state:MA],names=[bob mike rob]",
+		},
+		{
+			"with complex types",
+			"default",
+			"email:send",
+			map[string]interface{}{
+				"time":     time.Date(2020, time.July, 28, 0, 0, 0, 0, time.UTC),
+				"duration": time.Hour},
+			"asynq:{default}:unique:email:send:duration=1h0m0s,time=2020-07-28 00:00:00 +0000 UTC",
+		},
+		{
+			"with nil payload",
+			"default",
+			"reindex",
+			nil,
+			"asynq:{default}:unique:reindex:nil",
+		},
+	}
+
+	for _, tc := range tests {
+		got := UniqueKey(tc.qname, tc.tasktype, tc.payload)
+		if got != tc.want {
+			t.Errorf("%s: UniqueKey(%q, %q, %v) = %q, want %q", tc.desc, tc.qname, tc.tasktype, tc.payload, got, tc.want)
+		}
+	}
+}
+
 func TestMessageEncoding(t *testing.T) {
 	id := uuid.New()
 	tests := []struct {
@@ -166,14 +363,14 @@ func TestStatusConcurrentAccess(t *testing.T) {
 	go func() {
 		defer wg.Done()
 		status.Get()
-		status.String()
+		_ = status.String()
 	}()

 	wg.Add(1)
 	go func() {
 		defer wg.Done()
 		status.Set(StatusStopped)
-		status.String()
+		_ = status.String()
 	}()

 	wg.Wait()
--- a/internal/rdb/benchmark_test.go
+++ b/internal/rdb/benchmark_test.go
@@ -1,41 +0,0 @@
-// Copyright 2020 Kentaro Hibino. All rights reserved.
-// Use of this source code is governed by a MIT license
-// that can be found in the LICENSE file.
-
-package rdb
-
-import (
-	"testing"
-
-	"github.com/go-redis/redis/v7"
-	h "github.com/hibiken/asynq/internal/asynqtest"
-	"github.com/hibiken/asynq/internal/base"
-)
-
-func BenchmarkDone(b *testing.B) {
-	r := redis.NewClient(&redis.Options{
-		Addr: "localhost:6379",
-		DB:   8,
-	})
-	h.FlushDB(b, r)
-
-	// populate in-progress queue with messages
-	var inProgress []*base.TaskMessage
-	for i := 0; i < 40; i++ {
-		inProgress = append(inProgress,
-			h.NewTaskMessage("send_email", map[string]interface{}{"subject": "hello", "recipient_id": 123}))
-	}
-	h.SeedInProgressQueue(b, r, inProgress)
-
-	rdb := NewRDB(r)
-
-	b.ResetTimer()
-	for n := 0; n < b.N; n++ {
-		b.StopTimer()
-		msg := h.NewTaskMessage("reindex", map[string]interface{}{"config": "path/to/config/file"})
-		r.LPush(base.InProgressQueue, h.MustMarshal(b, msg))
-		b.StartTimer()
-
-		rdb.Done(msg)
-	}
-}
--- a/internal/rdb/inspect.go
+++ b/internal/rdb/inspect.go
--- a/internal/rdb/inspect_test.go
+++ b/internal/rdb/inspect_test.go
--- a/internal/rdb/rdb.go
+++ b/internal/rdb/rdb.go
@@ -32,11 +32,11 @@ const statsTTL = 90 * 24 * time.Hour // 90 days

 // RDB is a client interface to query and mutate task queues.
 type RDB struct {
-	client *redis.Client
+	client redis.UniversalClient
 }

 // NewRDB returns a new instance of RDB.
-func NewRDB(client *redis.Client) *RDB {
+func NewRDB(client redis.UniversalClient) *RDB {
 	return &RDB{client}
 }

@@ -45,13 +45,10 @@ func (r *RDB) Close() error {
 	return r.client.Close()
 }

-// KEYS[1] -> asynq:queues:<qname>
-// KEYS[2] -> asynq:queues
-// ARGV[1] -> task message data
-var enqueueCmd = redis.NewScript(`
-redis.call("LPUSH", KEYS[1], ARGV[1])
-redis.call("SADD", KEYS[2], KEYS[1])
-return 1`)
+// Ping checks the connection with redis server.
+func (r *RDB) Ping() error {
+	return r.client.Ping().Err()
+}

 // Enqueue inserts the given task to the tail of the queue.
 func (r *RDB) Enqueue(msg *base.TaskMessage) error {
@@ -59,13 +56,15 @@ func (r *RDB) Enqueue(msg *base.TaskMessage) error {
 	if err != nil {
 		return err
 	}
+	if err := r.client.SAdd(base.AllQueues, msg.Queue).Err(); err != nil {
+		return err
+	}
 	key := base.QueueKey(msg.Queue)
-	return enqueueCmd.Run(r.client, []string{key, base.AllQueues}, encoded).Err()
+	return r.client.LPush(key, encoded).Err()
 }

-// KEYS[1] -> unique key in the form <type>:<payload>:<qname>
-// KEYS[2] -> asynq:queues:<qname>
-// KEYS[2] -> asynq:queues
+// KEYS[1] -> unique key
+// KEYS[2] -> asynq:{<qname>}
 // ARGV[1] -> task ID
 // ARGV[2] -> uniqueness lock TTL
 // ARGV[3] -> task message data
@@ -75,7 +74,6 @@ if not ok then
  return 0
 end
 redis.call("LPUSH", KEYS[2], ARGV[3])
-redis.call("SADD", KEYS[3], KEYS[2])
 return 1
 `)

@@ -86,9 +84,11 @@ func (r *RDB) EnqueueUnique(msg *base.TaskMessage, ttl time.Duration) error {
 	if err != nil {
 		return err
 	}
-	key := base.QueueKey(msg.Queue)
+	if err := r.client.SAdd(base.AllQueues, msg.Queue).Err(); err != nil {
+		return err
+	}
 	res, err := enqueueUniqueCmd.Run(r.client,
-		[]string{msg.UniqueKey, key, base.AllQueues},
+		[]string{msg.UniqueKey, base.QueueKey(msg.Queue)},
 		msg.ID.String(), int(ttl.Seconds()), encoded).Result()
 	if err != nil {
 		return err
@@ -108,14 +108,7 @@ func (r *RDB) EnqueueUnique(msg *base.TaskMessage, ttl time.Duration) error {
 // Dequeue skips a queue if the queue is paused.
 // If all queues are empty, ErrNoProcessableTask error is returned.
 func (r *RDB) Dequeue(qnames ...string) (msg *base.TaskMessage, deadline time.Time, err error) {
-	var qkeys []interface{}
-	for _, q := range qnames {
-		qkeys = append(qkeys, base.QueueKey(q))
-	}
-	data, d, err := r.dequeue(qkeys...)
-	if err == redis.Nil {
-		return nil, time.Time{}, ErrNoProcessableTask
-	}
+	data, d, err := r.dequeue(qnames...)
 	if err != nil {
 		return nil, time.Time{}, err
 	}
@@ -125,75 +118,76 @@ func (r *RDB) Dequeue(qnames ...string) (msg *base.TaskMessage, deadline time.Ti
 	return msg, time.Unix(d, 0), nil
 }

-// KEYS[1]  -> asynq:in_progress
-// KEYS[2]  -> asynq:paused
-// KEYS[3]  -> asynq:deadlines
+// KEYS[1] -> asynq:{<qname>}
+// KEYS[2] -> asynq:{<qname>}:paused
+// KEYS[3] -> asynq:{<qname>}:active
+// KEYS[4] -> asynq:{<qname>}:deadlines
 // ARGV[1]  -> current time in Unix time
-// ARGV[2:] -> List of queues to query in order
 //
 // dequeueCmd checks whether a queue is paused first, before
 // calling RPOPLPUSH to pop a task from the queue.
 // It computes the task deadline by inspecting Timout and Deadline fields,
 // and inserts the task with deadlines set.
 var dequeueCmd = redis.NewScript(`
-for i = 2, table.getn(ARGV) do
-	local qkey = ARGV[i]
-	if redis.call("SISMEMBER", KEYS[2], qkey) == 0 then
-		local msg = redis.call("RPOPLPUSH", qkey, KEYS[1])
-		if msg then
-			local decoded = cjson.decode(msg)
-			local timeout = decoded["Timeout"]
-			local deadline = decoded["Deadline"]
-			local score
-			if timeout ~= 0 and deadline ~= 0 then
-				score = math.min(ARGV[1]+timeout, deadline)
-			elseif timeout ~= 0 then
-				score = ARGV[1] + timeout
-			elseif deadline ~= 0 then
-				score = deadline
-			else
-				return redis.error_reply("asynq internal error: both timeout and deadline are not set")
-			end
-			redis.call("ZADD", KEYS[3], score, msg)
-			return {msg, score}
+if redis.call("EXISTS", KEYS[2]) == 0 then
+	local msg = redis.call("RPOPLPUSH", KEYS[1], KEYS[3])
+	if msg then
+		local decoded = cjson.decode(msg)
+		local timeout = decoded["Timeout"]
+		local deadline = decoded["Deadline"]
+		local score
+		if timeout ~= 0 and deadline ~= 0 then
+			score = math.min(ARGV[1]+timeout, deadline)
+		elseif timeout ~= 0 then
+			score = ARGV[1] + timeout
+		elseif deadline ~= 0 then
+			score = deadline
+		else
+			return redis.error_reply("asynq internal error: both timeout and deadline are not set")
 		end
+		redis.call("ZADD", KEYS[4], score, msg)
+		return {msg, score}
 	end
 end
 return nil`)

-func (r *RDB) dequeue(qkeys ...interface{}) (msgjson string, deadline int64, err error) {
-	var args []interface{}
-	args = append(args, time.Now().Unix())
-	args = append(args, qkeys...)
-	res, err := dequeueCmd.Run(r.client,
-		[]string{base.InProgressQueue, base.PausedQueues, base.KeyDeadlines}, args...).Result()
-	if err != nil {
-		return "", 0, err
+func (r *RDB) dequeue(qnames ...string) (msgjson string, deadline int64, err error) {
+	for _, qname := range qnames {
+		keys := []string{
+			base.QueueKey(qname),
+			base.PausedKey(qname),
+			base.ActiveKey(qname),
+			base.DeadlinesKey(qname),
+		}
+		res, err := dequeueCmd.Run(r.client, keys, time.Now().Unix()).Result()
+		if err == redis.Nil {
+			continue
+		} else if err != nil {
+			return "", 0, err
+		}
+		data, err := cast.ToSliceE(res)
+		if err != nil {
+			return "", 0, err
+		}
+		if len(data) != 2 {
+			return "", 0, fmt.Errorf("asynq: internal error: dequeue command returned %d values", len(data))
+		}
+		if msgjson, err = cast.ToStringE(data[0]); err != nil {
+			return "", 0, err
+		}
+		if deadline, err = cast.ToInt64E(data[1]); err != nil {
+			return "", 0, err
+		}
+		return msgjson, deadline, nil
 	}
-	data, err := cast.ToSliceE(res)
-	if err != nil {
-		return "", 0, err
-	}
-	if len(data) != 2 {
-		return "", 0, fmt.Errorf("asynq: internal error: dequeue command returned %d values", len(data))
-	}
-	if msgjson, err = cast.ToStringE(data[0]); err != nil {
-		return "", 0, err
-	}
-	if deadline, err = cast.ToInt64E(data[1]); err != nil {
-		return "", 0, err
-	}
-	return msgjson, deadline, nil
+	return "", 0, ErrNoProcessableTask
 }

-// KEYS[1] -> asynq:in_progress
-// KEYS[2] -> asynq:deadlines
-// KEYS[3] -> asynq:processed:<yyyy-mm-dd>
-// KEYS[4] -> unique key in the format <type>:<payload>:<qname>
+// KEYS[1] -> asynq:{<qname>}:active
+// KEYS[2] -> asynq:{<qname>}:deadlines
+// KEYS[3] -> asynq:{<qname>}:processed:<yyyy-mm-dd>
 // ARGV[1] -> base.TaskMessage value
 // ARGV[2] -> stats expiration timestamp
-// ARGV[3] -> task ID
-// Note: LREM count ZERO means "remove all elements equal to val"
 var doneCmd = redis.NewScript(`
 if redis.call("LREM", KEYS[1], 0, ARGV[1]) == 0 then
  return redis.error_reply("NOT FOUND")
@@ -205,13 +199,34 @@ local n = redis.call("INCR", KEYS[3])
 if tonumber(n) == 1 then
 	redis.call("EXPIREAT", KEYS[3], ARGV[2])
 end
-if string.len(KEYS[4]) > 0 and redis.call("GET", KEYS[4]) == ARGV[3] then
+return redis.status_reply("OK")
+`)
+
+// KEYS[1] -> asynq:{<qname>}:active
+// KEYS[2] -> asynq:{<qname>}:deadlines
+// KEYS[3] -> asynq:{<qname>}:processed:<yyyy-mm-dd>
+// KEYS[4] -> unique key
+// ARGV[1] -> base.TaskMessage value
+// ARGV[2] -> stats expiration timestamp
+// ARGV[3] -> task ID
+var doneUniqueCmd = redis.NewScript(`
+if redis.call("LREM", KEYS[1], 0, ARGV[1]) == 0 then
+  return redis.error_reply("NOT FOUND")
+end
+if redis.call("ZREM", KEYS[2], ARGV[1]) == 0 then
+  return redis.error_reply("NOT FOUND")
+end
+local n = redis.call("INCR", KEYS[3])
+if tonumber(n) == 1 then
+	redis.call("EXPIREAT", KEYS[3], ARGV[2])
+end
+if redis.call("GET", KEYS[4]) == ARGV[3] then
  redis.call("DEL", KEYS[4])
 end
 return redis.status_reply("OK")
 `)

-// Done removes the task from in-progress queue to mark the task as done.
+// Done removes the task from active queue to mark the task as done.
 // It removes a uniqueness lock acquired by the task, if any.
 func (r *RDB) Done(msg *base.TaskMessage) error {
 	encoded, err := base.EncodeMessage(msg)
@@ -219,16 +234,24 @@ func (r *RDB) Done(msg *base.TaskMessage) error {
 		return err
 	}
 	now := time.Now()
-	processedKey := base.ProcessedKey(now)
 	expireAt := now.Add(statsTTL)
-	return doneCmd.Run(r.client,
-		[]string{base.InProgressQueue, base.KeyDeadlines, processedKey, msg.UniqueKey},
-		encoded, expireAt.Unix(), msg.ID.String()).Err()
+	keys := []string{
+		base.ActiveKey(msg.Queue),
+		base.DeadlinesKey(msg.Queue),
+		base.ProcessedKey(msg.Queue, now),
+	}
+	args := []interface{}{encoded, expireAt.Unix()}
+	if len(msg.UniqueKey) > 0 {
+		keys = append(keys, msg.UniqueKey)
+		args = append(args, msg.ID.String())
+		return doneUniqueCmd.Run(r.client, keys, args...).Err()
+	}
+	return doneCmd.Run(r.client, keys, args...).Err()
 }

-// KEYS[1] -> asynq:in_progress
-// KEYS[2] -> asynq:deadlines
-// KEYS[3] -> asynq:queues:<qname>
+// KEYS[1] -> asynq:{<qname>}:active
+// KEYS[2] -> asynq:{<qname>}:deadlines
+// KEYS[3] -> asynq:{<qname>}
 // ARGV[1] -> base.TaskMessage value
 // Note: Use RPUSH to push to the head of the queue.
 var requeueCmd = redis.NewScript(`
@@ -241,56 +264,42 @@ end
 redis.call("RPUSH", KEYS[3], ARGV[1])
 return redis.status_reply("OK")`)

-// Requeue moves the task from in-progress queue to the specified queue.
+// Requeue moves the task from active queue to the specified queue.
 func (r *RDB) Requeue(msg *base.TaskMessage) error {
 	encoded, err := base.EncodeMessage(msg)
 	if err != nil {
 		return err
 	}
 	return requeueCmd.Run(r.client,
-		[]string{base.InProgressQueue, base.KeyDeadlines, base.QueueKey(msg.Queue)},
+		[]string{base.ActiveKey(msg.Queue), base.DeadlinesKey(msg.Queue), base.QueueKey(msg.Queue)},
 		encoded).Err()
 }

-// KEYS[1] -> asynq:scheduled
-// KEYS[2] -> asynq:queues
-// ARGV[1] -> score (process_at timestamp)
-// ARGV[2] -> task message
-// ARGV[3] -> queue key
-var scheduleCmd = redis.NewScript(`
-redis.call("ZADD", KEYS[1], ARGV[1], ARGV[2])
-redis.call("SADD", KEYS[2], ARGV[3])
-return 1
-`)
-
 // Schedule adds the task to the backlog queue to be processed in the future.
 func (r *RDB) Schedule(msg *base.TaskMessage, processAt time.Time) error {
 	encoded, err := base.EncodeMessage(msg)
 	if err != nil {
 		return err
 	}
-	qkey := base.QueueKey(msg.Queue)
+	if err := r.client.SAdd(base.AllQueues, msg.Queue).Err(); err != nil {
+		return err
+	}
 	score := float64(processAt.Unix())
-	return scheduleCmd.Run(r.client,
-		[]string{base.ScheduledQueue, base.AllQueues},
-		score, encoded, qkey).Err()
+	return r.client.ZAdd(base.ScheduledKey(msg.Queue), &redis.Z{Score: score, Member: encoded}).Err()
 }

-// KEYS[1] -> unique key in the format <type>:<payload>:<qname>
-// KEYS[2] -> asynq:scheduled
-// KEYS[3] -> asynq:queues
+// KEYS[1] -> unique key
+// KEYS[2] -> asynq:{<qname>}:scheduled
 // ARGV[1] -> task ID
 // ARGV[2] -> uniqueness lock TTL
 // ARGV[3] -> score (process_at timestamp)
 // ARGV[4] -> task message
-// ARGV[5] -> queue key
 var scheduleUniqueCmd = redis.NewScript(`
 local ok = redis.call("SET", KEYS[1], ARGV[1], "NX", "EX", ARGV[2])
 if not ok then
  return 0
 end
 redis.call("ZADD", KEYS[2], ARGV[3], ARGV[4])
-redis.call("SADD", KEYS[3], ARGV[5])
 return 1
 `)

@@ -301,11 +310,13 @@ func (r *RDB) ScheduleUnique(msg *base.TaskMessage, processAt time.Time, ttl tim
 	if err != nil {
 		return err
 	}
-	qkey := base.QueueKey(msg.Queue)
+	if err := r.client.SAdd(base.AllQueues, msg.Queue).Err(); err != nil {
+		return err
+	}
 	score := float64(processAt.Unix())
 	res, err := scheduleUniqueCmd.Run(r.client,
-		[]string{msg.UniqueKey, base.ScheduledQueue, base.AllQueues},
-		msg.ID.String(), int(ttl.Seconds()), score, encoded, qkey).Result()
+		[]string{msg.UniqueKey, base.ScheduledKey(msg.Queue)},
+		msg.ID.String(), int(ttl.Seconds()), score, encoded).Result()
 	if err != nil {
 		return err
 	}
@@ -319,12 +330,12 @@ func (r *RDB) ScheduleUnique(msg *base.TaskMessage, processAt time.Time, ttl tim
 	return nil
 }

-// KEYS[1] -> asynq:in_progress
-// KEYS[2] -> asynq:deadlines
-// KEYS[3] -> asynq:retry
-// KEYS[4] -> asynq:processed:<yyyy-mm-dd>
-// KEYS[5] -> asynq:failure:<yyyy-mm-dd>
-// ARGV[1] -> base.TaskMessage value to remove from base.InProgressQueue queue
+// KEYS[1] -> asynq:{<qname>}:active
+// KEYS[2] -> asynq:{<qname>}:deadlines
+// KEYS[3] -> asynq:{<qname>}:retry
+// KEYS[4] -> asynq:{<qname>}:processed:<yyyy-mm-dd>
+// KEYS[5] -> asynq:{<qname>}:failed:<yyyy-mm-dd>
+// ARGV[1] -> base.TaskMessage value to remove from base.ActiveQueue queue
 // ARGV[2] -> base.TaskMessage value to add to Retry queue
 // ARGV[3] -> retry_at UNIX timestamp
 // ARGV[4] -> stats expiration timestamp
@@ -346,7 +357,7 @@ if tonumber(m) == 1 then
 end
 return redis.status_reply("OK")`)

-// Retry moves the task from in-progress to retry queue, incrementing retry count
+// Retry moves the task from active to retry queue, incrementing retry count
 // and assigning error message to the task message.
 func (r *RDB) Retry(msg *base.TaskMessage, processAt time.Time, errMsg string) error {
 	msgToRemove, err := base.EncodeMessage(msg)
@@ -361,31 +372,31 @@ func (r *RDB) Retry(msg *base.TaskMessage, processAt time.Time, errMsg string) e
 		return err
 	}
 	now := time.Now()
-	processedKey := base.ProcessedKey(now)
-	failureKey := base.FailureKey(now)
+	processedKey := base.ProcessedKey(msg.Queue, now)
+	failedKey := base.FailedKey(msg.Queue, now)
 	expireAt := now.Add(statsTTL)
 	return retryCmd.Run(r.client,
-		[]string{base.InProgressQueue, base.KeyDeadlines, base.RetryQueue, processedKey, failureKey},
+		[]string{base.ActiveKey(msg.Queue), base.DeadlinesKey(msg.Queue), base.RetryKey(msg.Queue), processedKey, failedKey},
 		msgToRemove, msgToAdd, processAt.Unix(), expireAt.Unix()).Err()
 }

 const (
-	maxDeadTasks         = 10000
-	deadExpirationInDays = 90
+	maxArchiveSize           = 10000 // maximum number of tasks in archive
+	archivedExpirationInDays = 90    // number of days before an archived task gets deleted permanently
 )

-// KEYS[1] -> asynq:in_progress
-// KEYS[2] -> asynq:deadlines
-// KEYS[3] -> asynq:dead
-// KEYS[4] -> asynq:processed:<yyyy-mm-dd>
-// KEYS[5] -> asynq.failure:<yyyy-mm-dd>
-// ARGV[1] -> base.TaskMessage value to remove from base.InProgressQueue queue
-// ARGV[2] -> base.TaskMessage value to add to Dead queue
+// KEYS[1] -> asynq:{<qname>}:active
+// KEYS[2] -> asynq:{<qname>}:deadlines
+// KEYS[3] -> asynq:{<qname>}:archived
+// KEYS[4] -> asynq:{<qname>}:processed:<yyyy-mm-dd>
+// KEYS[5] -> asynq:{<qname>}:failed:<yyyy-mm-dd>
+// ARGV[1] -> base.TaskMessage value to remove
+// ARGV[2] -> base.TaskMessage value to add
 // ARGV[3] -> died_at UNIX timestamp
 // ARGV[4] -> cutoff timestamp (e.g., 90 days ago)
-// ARGV[5] -> max number of tasks in dead queue (e.g., 100)
+// ARGV[5] -> max number of tasks in archive (e.g., 100)
 // ARGV[6] -> stats expiration timestamp
-var killCmd = redis.NewScript(`
+var archiveCmd = redis.NewScript(`
 if redis.call("LREM", KEYS[1], 0, ARGV[1]) == 0 then
  return redis.error_reply("NOT FOUND")
 end
@@ -405,10 +416,9 @@ if tonumber(m) == 1 then
 end
 return redis.status_reply("OK")`)

-// Kill sends the task to "dead" queue from in-progress queue, assigning
-// the error message to the task.
-// It also trims the set by timestamp and set size.
-func (r *RDB) Kill(msg *base.TaskMessage, errMsg string) error {
+// Archive sends the given task to archive, attaching the error message to the task.
+// It also trims the archive by timestamp and set size.
+func (r *RDB) Archive(msg *base.TaskMessage, errMsg string) error {
 	msgToRemove, err := base.EncodeMessage(msg)
 	if err != nil {
 		return err
@@ -420,97 +430,102 @@ func (r *RDB) Kill(msg *base.TaskMessage, errMsg string) error {
 		return err
 	}
 	now := time.Now()
-	limit := now.AddDate(0, 0, -deadExpirationInDays).Unix() // 90 days ago
-	processedKey := base.ProcessedKey(now)
-	failureKey := base.FailureKey(now)
+	limit := now.AddDate(0, 0, -archivedExpirationInDays).Unix() // 90 days ago
+	processedKey := base.ProcessedKey(msg.Queue, now)
+	failedKey := base.FailedKey(msg.Queue, now)
 	expireAt := now.Add(statsTTL)
-	return killCmd.Run(r.client,
-		[]string{base.InProgressQueue, base.KeyDeadlines, base.DeadQueue, processedKey, failureKey},
-		msgToRemove, msgToAdd, now.Unix(), limit, maxDeadTasks, expireAt.Unix()).Err()
+	return archiveCmd.Run(r.client,
+		[]string{base.ActiveKey(msg.Queue), base.DeadlinesKey(msg.Queue), base.ArchivedKey(msg.Queue), processedKey, failedKey},
+		msgToRemove, msgToAdd, now.Unix(), limit, maxArchiveSize, expireAt.Unix()).Err()
 }

-// CheckAndEnqueue checks for all scheduled/retry tasks and enqueues any tasks that
-// are ready to be processed.
-func (r *RDB) CheckAndEnqueue() (err error) {
-	delayed := []string{base.ScheduledQueue, base.RetryQueue}
-	for _, zset := range delayed {
-		n := 1
-		for n != 0 {
-			n, err = r.forward(zset)
-			if err != nil {
-				return err
-			}
+// CheckAndEnqueue checks for scheduled/retry tasks for the given queues
+//and enqueues any tasks that  are ready to be processed.
+func (r *RDB) CheckAndEnqueue(qnames ...string) error {
+	for _, qname := range qnames {
+		if err := r.forwardAll(base.ScheduledKey(qname), base.QueueKey(qname)); err != nil {
+			return err
+		}
+		if err := r.forwardAll(base.RetryKey(qname), base.QueueKey(qname)); err != nil {
+			return err
 		}
 	}
 	return nil
 }

-// KEYS[1] -> source queue (e.g. scheduled or retry queue)
+// KEYS[1] -> source queue (e.g. asynq:{<qname>:scheduled or asynq:{<qname>}:retry})
+// KEYS[2] -> destination queue (e.g. asynq:{<qname>})
 // ARGV[1] -> current unix time
-// ARGV[2] -> queue prefix
 // Note: Script moves tasks up to 100 at a time to keep the runtime of script short.
 var forwardCmd = redis.NewScript(`
 local msgs = redis.call("ZRANGEBYSCORE", KEYS[1], "-inf", ARGV[1], "LIMIT", 0, 100)
 for _, msg in ipairs(msgs) do
-	local decoded = cjson.decode(msg)
-	local qkey = ARGV[2] .. decoded["Queue"]
-	redis.call("LPUSH", qkey, msg)
+	redis.call("LPUSH", KEYS[2], msg)
 	redis.call("ZREM", KEYS[1], msg)
 end
 return table.getn(msgs)`)

 // forward moves tasks with a score less than the current unix time
-// from the src zset. It returns the number of tasks moved.
-func (r *RDB) forward(src string) (int, error) {
+// from the src zset to the dst list. It returns the number of tasks moved.
+func (r *RDB) forward(src, dst string) (int, error) {
 	now := float64(time.Now().Unix())
-	res, err := forwardCmd.Run(r.client,
-		[]string{src}, now, base.QueuePrefix).Result()
+	res, err := forwardCmd.Run(r.client, []string{src, dst}, now).Result()
 	if err != nil {
 		return 0, err
 	}
 	return cast.ToInt(res), nil
 }

-// ListDeadlineExceeded returns a list of task messages that have exceeded the given deadline.
-func (r *RDB) ListDeadlineExceeded(deadline time.Time) ([]*base.TaskMessage, error) {
+// forwardAll moves tasks with a score less than the current unix time from the src zset,
+// until there's no more tasks.
+func (r *RDB) forwardAll(src, dst string) (err error) {
+	n := 1
+	for n != 0 {
+		n, err = r.forward(src, dst)
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// ListDeadlineExceeded returns a list of task messages that have exceeded the deadline from the given queues.
+func (r *RDB) ListDeadlineExceeded(deadline time.Time, qnames ...string) ([]*base.TaskMessage, error) {
 	var msgs []*base.TaskMessage
 	opt := &redis.ZRangeBy{
 		Min: "-inf",
 		Max: strconv.FormatInt(deadline.Unix(), 10),
 	}
-	res, err := r.client.ZRangeByScore(base.KeyDeadlines, opt).Result()
-	if err != nil {
-		return nil, err
-	}
-	for _, s := range res {
-		msg, err := base.DecodeMessage(s)
+	for _, qname := range qnames {
+		res, err := r.client.ZRangeByScore(base.DeadlinesKey(qname), opt).Result()
 		if err != nil {
 			return nil, err
 		}
-		msgs = append(msgs, msg)
+		for _, s := range res {
+			msg, err := base.DecodeMessage(s)
+			if err != nil {
+				return nil, err
+			}
+			msgs = append(msgs, msg)
+		}
 	}
 	return msgs, nil
 }

-// KEYS[1]  -> asynq:servers:<host:pid:sid>
-// KEYS[2]  -> asynq:servers
-// KEYS[3]  -> asynq:workers<host:pid:sid>
-// KEYS[4]  -> asynq:workers
-// ARGV[1]  -> expiration time
-// ARGV[2]  -> TTL in seconds
-// ARGV[3]  -> server info
-// ARGV[4:] -> alternate key-value pair of (worker id, worker data)
+// KEYS[1]  -> asynq:servers:{<host:pid:sid>}
+// KEYS[2]  -> asynq:workers:{<host:pid:sid>}
+// ARGV[1]  -> TTL in seconds
+// ARGV[2]  -> server info
+// ARGV[3:] -> alternate key-value pair of (worker id, worker data)
 // Note: Add key to ZSET with expiration time as score.
 // ref: https://github.com/antirez/redis/issues/135#issuecomment-2361996
 var writeServerStateCmd = redis.NewScript(`
-redis.call("SETEX", KEYS[1], ARGV[2], ARGV[3])
-redis.call("ZADD", KEYS[2], ARGV[1], KEYS[1])
-redis.call("DEL", KEYS[3])
-for i = 4, table.getn(ARGV)-1, 2 do
-	redis.call("HSET", KEYS[3], ARGV[i], ARGV[i+1])
+redis.call("SETEX", KEYS[1], ARGV[1], ARGV[2])
+redis.call("DEL", KEYS[2])
+for i = 3, table.getn(ARGV)-1, 2 do
+	redis.call("HSET", KEYS[2], ARGV[i], ARGV[i+1])
 end
-redis.call("EXPIRE", KEYS[3], ARGV[2])
-redis.call("ZADD", KEYS[4], ARGV[1], KEYS[3])
+redis.call("EXPIRE", KEYS[2], ARGV[1])
 return redis.status_reply("OK")`)

 // WriteServerState writes server state data to redis with expiration set to the value ttl.
@@ -520,7 +535,7 @@ func (r *RDB) WriteServerState(info *base.ServerInfo, workers []*base.WorkerInfo
 		return err
 	}
 	exp := time.Now().Add(ttl).UTC()
-	args := []interface{}{float64(exp.Unix()), ttl.Seconds(), bytes} // args to the lua script
+	args := []interface{}{ttl.Seconds(), bytes} // args to the lua script
 	for _, w := range workers {
 		bytes, err := json.Marshal(w)
 		if err != nil {
@@ -530,28 +545,72 @@ func (r *RDB) WriteServerState(info *base.ServerInfo, workers []*base.WorkerInfo
 	}
 	skey := base.ServerInfoKey(info.Host, info.PID, info.ServerID)
 	wkey := base.WorkersKey(info.Host, info.PID, info.ServerID)
-	return writeServerStateCmd.Run(r.client,
-		[]string{skey, base.AllServers, wkey, base.AllWorkers},
-		args...).Err()
+	if err := r.client.ZAdd(base.AllServers, &redis.Z{Score: float64(exp.Unix()), Member: skey}).Err(); err != nil {
+		return err
+	}
+	if err := r.client.ZAdd(base.AllWorkers, &redis.Z{Score: float64(exp.Unix()), Member: wkey}).Err(); err != nil {
+		return err
+	}
+	return writeServerStateCmd.Run(r.client, []string{skey, wkey}, args...).Err()
 }

-// KEYS[1] -> asynq:servers
-// KEYS[2] -> asynq:servers:<host:pid:sid>
-// KEYS[3] -> asynq:workers
-// KEYS[4] -> asynq:workers<host:pid:sid>
+// KEYS[1] -> asynq:servers:{<host:pid:sid>}
+// KEYS[2] -> asynq:workers:{<host:pid:sid>}
 var clearServerStateCmd = redis.NewScript(`
-redis.call("ZREM", KEYS[1], KEYS[2])
+redis.call("DEL", KEYS[1])
 redis.call("DEL", KEYS[2])
-redis.call("ZREM", KEYS[3], KEYS[4])
-redis.call("DEL", KEYS[4])
 return redis.status_reply("OK")`)

 // ClearServerState deletes server state data from redis.
 func (r *RDB) ClearServerState(host string, pid int, serverID string) error {
 	skey := base.ServerInfoKey(host, pid, serverID)
 	wkey := base.WorkersKey(host, pid, serverID)
-	return clearServerStateCmd.Run(r.client,
-		[]string{base.AllServers, skey, base.AllWorkers, wkey}).Err()
+	if err := r.client.ZRem(base.AllServers, skey).Err(); err != nil {
+		return err
+	}
+	if err := r.client.ZRem(base.AllWorkers, wkey).Err(); err != nil {
+		return err
+	}
+	return clearServerStateCmd.Run(r.client, []string{skey, wkey}).Err()
+}
+
+// KEYS[1]  -> asynq:schedulers:{<schedulerID>}
+// ARGV[1]  -> TTL in seconds
+// ARGV[2:] -> schedler entries
+var writeSchedulerEntriesCmd = redis.NewScript(`
+redis.call("DEL", KEYS[1])
+for i = 2, #ARGV do
+	redis.call("LPUSH", KEYS[1], ARGV[i])
+end
+redis.call("EXPIRE", KEYS[1], ARGV[1])
+return redis.status_reply("OK")`)
+
+// WriteSchedulerEntries writes scheduler entries data to redis with expiration set to the value ttl.
+func (r *RDB) WriteSchedulerEntries(schedulerID string, entries []*base.SchedulerEntry, ttl time.Duration) error {
+	args := []interface{}{ttl.Seconds()}
+	for _, e := range entries {
+		bytes, err := json.Marshal(e)
+		if err != nil {
+			continue // skip bad data
+		}
+		args = append(args, bytes)
+	}
+	exp := time.Now().Add(ttl).UTC()
+	key := base.SchedulerEntriesKey(schedulerID)
+	err := r.client.ZAdd(base.AllSchedulers, &redis.Z{Score: float64(exp.Unix()), Member: key}).Err()
+	if err != nil {
+		return err
+	}
+	return writeSchedulerEntriesCmd.Run(r.client, []string{key}, args...).Err()
+}
+
+// ClearSchedulerEntries deletes scheduler entries data from redis.
+func (r *RDB) ClearSchedulerEntries(scheduelrID string) error {
+	key := base.SchedulerEntriesKey(scheduelrID)
+	if err := r.client.ZRem(base.AllSchedulers, key).Err(); err != nil {
+		return err
+	}
+	return r.client.Del(key).Err()
 }

 // CancelationPubSub returns a pubsub for cancelation messages.
@@ -569,3 +628,26 @@ func (r *RDB) CancelationPubSub() (*redis.PubSub, error) {
 func (r *RDB) PublishCancelation(id string) error {
 	return r.client.Publish(base.CancelChannel, id).Err()
 }
+
+// KEYS[1] -> asynq:scheduler_history:<entryID>
+// ARGV[1] -> enqueued_at timestamp
+// ARGV[2] -> serialized SchedulerEnqueueEvent data
+// ARGV[3] -> max number of events to be persisted
+var recordSchedulerEnqueueEventCmd = redis.NewScript(`
+redis.call("ZADD", KEYS[1], ARGV[1], ARGV[2])
+redis.call("ZREMRANGEBYSCORE", KEYS[1], "-inf", ARGV[3])
+return redis.status_reply("OK")`)
+
+// Maximum number of enqueue events to store per entry.
+const maxEvents = 10000
+
+// RecordSchedulerEnqueueEvent records the time when the given task was enqueued.
+func (r *RDB) RecordSchedulerEnqueueEvent(entryID string, event *base.SchedulerEnqueueEvent) error {
+	key := base.SchedulerHistoryKey(entryID)
+	data, err := json.Marshal(event)
+	if err != nil {
+		return err
+	}
+	return recordSchedulerEnqueueEventCmd.Run(
+		r.client, []string{key}, event.EnqueuedAt.Unix(), data, maxEvents).Err()
+}
--- a/internal/rdb/rdb_test.go
+++ b/internal/rdb/rdb_test.go
--- a/internal/testbroker/testbroker.go
+++ b/internal/testbroker/testbroker.go
@@ -117,31 +117,31 @@ func (tb *TestBroker) Retry(msg *base.TaskMessage, processAt time.Time, errMsg s
 	return tb.real.Retry(msg, processAt, errMsg)
 }

-func (tb *TestBroker) Kill(msg *base.TaskMessage, errMsg string) error {
+func (tb *TestBroker) Archive(msg *base.TaskMessage, errMsg string) error {
 	tb.mu.Lock()
 	defer tb.mu.Unlock()
 	if tb.sleeping {
 		return errRedisDown
 	}
-	return tb.real.Kill(msg, errMsg)
+	return tb.real.Archive(msg, errMsg)
 }

-func (tb *TestBroker) CheckAndEnqueue() error {
+func (tb *TestBroker) CheckAndEnqueue(qnames ...string) error {
 	tb.mu.Lock()
 	defer tb.mu.Unlock()
 	if tb.sleeping {
 		return errRedisDown
 	}
-	return tb.real.CheckAndEnqueue()
+	return tb.real.CheckAndEnqueue(qnames...)
 }

-func (tb *TestBroker) ListDeadlineExceeded(deadline time.Time) ([]*base.TaskMessage, error) {
+func (tb *TestBroker) ListDeadlineExceeded(deadline time.Time, qnames ...string) ([]*base.TaskMessage, error) {
 	tb.mu.Lock()
 	defer tb.mu.Unlock()
 	if tb.sleeping {
 		return nil, errRedisDown
 	}
-	return tb.real.ListDeadlineExceeded(deadline)
+	return tb.real.ListDeadlineExceeded(deadline, qnames...)
 }

 func (tb *TestBroker) WriteServerState(info *base.ServerInfo, workers []*base.WorkerInfo, ttl time.Duration) error {
@@ -180,6 +180,15 @@ func (tb *TestBroker) PublishCancelation(id string) error {
 	return tb.real.PublishCancelation(id)
 }

+func (tb *TestBroker) Ping() error {
+	tb.mu.Lock()
+	defer tb.mu.Unlock()
+	if tb.sleeping {
+		return errRedisDown
+	}
+	return tb.real.Ping()
+}
+
 func (tb *TestBroker) Close() error {
 	tb.mu.Lock()
 	defer tb.mu.Unlock()
--- a/payload.go
+++ b/payload.go
@@ -44,6 +44,16 @@ func toInt(v interface{}) (int, error) {
 	}
 }

+// String returns a string representation of payload data.
+func (p Payload) String() string {
+	return fmt.Sprint(p.data)
+}
+
+// MarshalJSON returns the JSON encoding of payload data.
+func (p Payload) MarshalJSON() ([]byte, error) {
+	return json.Marshal(p.data)
+}
+
 // GetString returns a string value if a string type is associated with
 // the key, otherwise reports an error.
 func (p Payload) GetString(key string) (string, error) {
--- a/payload_test.go
+++ b/payload_test.go
@@ -6,6 +6,7 @@ package asynq

 import (
 	"encoding/json"
+	"fmt"
 	"testing"
 	"time"

@@ -645,3 +646,30 @@ func TestPayloadHas(t *testing.T) {
 		t.Errorf("Payload.Has(%q) = true, want false", "name")
 	}
 }
+
+func TestPayloadDebuggingStrings(t *testing.T) {
+	data := map[string]interface{}{
+		"foo": 123,
+		"bar": "hello",
+		"baz": false,
+	}
+	payload := Payload{data: data}
+
+	if payload.String() != fmt.Sprint(data) {
+		t.Errorf("Payload.String() = %q, want %q",
+			payload.String(), fmt.Sprint(data))
+	}
+
+	got, err := payload.MarshalJSON()
+	if err != nil {
+		t.Fatal(err)
+	}
+	want, err := json.Marshal(data)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if diff := cmp.Diff(got, want); diff != "" {
+		t.Errorf("Payload.MarhsalJSON() = %s, want %s; (-want,+got)\n%s",
+			got, want, diff)
+	}
+}
--- a/processor.go
+++ b/processor.go
@@ -6,9 +6,13 @@ package asynq

 import (
 	"context"
+	"errors"
 	"fmt"
 	"math/rand"
+	"runtime"
+	"runtime/debug"
 	"sort"
+	"strings"
 	"sync"
 	"time"

@@ -29,7 +33,7 @@ type processor struct {
 	// orderedQueues is set only in strict-priority mode.
 	orderedQueues []string

-	retryDelayFunc retryDelayFunc
+	retryDelayFunc RetryDelayFunc

 	errHandler ErrorHandler

@@ -56,19 +60,17 @@ type processor struct {
 	// abort channel communicates to the in-flight worker goroutines to stop.
 	abort chan struct{}

-	// cancelations is a set of cancel functions for all in-progress tasks.
+	// cancelations is a set of cancel functions for all active tasks.
 	cancelations *base.Cancelations

 	starting chan<- *base.TaskMessage
 	finished chan<- *base.TaskMessage
 }

-type retryDelayFunc func(n int, err error, task *Task) time.Duration
-
 type processorParams struct {
 	logger          *log.Logger
 	broker          base.Broker
-	retryDelayFunc  retryDelayFunc
+	retryDelayFunc  RetryDelayFunc
 	syncCh          chan<- *syncRequest
 	cancelations    *base.Cancelations
 	concurrency     int
@@ -88,22 +90,23 @@ func newProcessor(params processorParams) *processor {
 		orderedQueues = sortByPriority(queues)
 	}
 	return &processor{
-		logger:         params.logger,
-		broker:         params.broker,
-		queueConfig:    queues,
-		orderedQueues:  orderedQueues,
-		retryDelayFunc: params.retryDelayFunc,
-		syncRequestCh:  params.syncCh,
-		cancelations:   params.cancelations,
-		errLogLimiter:  rate.NewLimiter(rate.Every(3*time.Second), 1),
-		sema:           make(chan struct{}, params.concurrency),
-		done:           make(chan struct{}),
-		quit:           make(chan struct{}),
-		abort:          make(chan struct{}),
-		errHandler:     params.errHandler,
-		handler:        HandlerFunc(func(ctx context.Context, t *Task) error { return fmt.Errorf("handler not set") }),
-		starting:       params.starting,
-		finished:       params.finished,
+		logger:          params.logger,
+		broker:          params.broker,
+		queueConfig:     queues,
+		orderedQueues:   orderedQueues,
+		retryDelayFunc:  params.retryDelayFunc,
+		syncRequestCh:   params.syncCh,
+		cancelations:    params.cancelations,
+		errLogLimiter:   rate.NewLimiter(rate.Every(3*time.Second), 1),
+		sema:            make(chan struct{}, params.concurrency),
+		done:            make(chan struct{}),
+		quit:            make(chan struct{}),
+		abort:           make(chan struct{}),
+		errHandler:      params.errHandler,
+		handler:         HandlerFunc(func(ctx context.Context, t *Task) error { return fmt.Errorf("handler not set") }),
+		shutdownTimeout: params.shutdownTimeout,
+		starting:        params.starting,
+		finished:        params.finished,
 	}
 }

@@ -202,7 +205,7 @@ func (p *processor) exec() {

 			resCh := make(chan error, 1)
 			go func() {
-				resCh <- perform(ctx, NewTask(msg.Type, msg.Payload), p.handler)
+				resCh <- p.perform(ctx, NewTask(msg.Type, msg.Payload))
 			}()

 			select {
@@ -216,9 +219,9 @@ func (p *processor) exec() {
 				return
 			case resErr := <-resCh:
 				// Note: One of three things should happen.
-				// 1) Done  -> Removes the message from InProgress
-				// 2) Retry -> Removes the message from InProgress & Adds the message to Retry
-				// 3) Kill  -> Removes the message from InProgress & Adds the message to Dead
+				// 1) Done     -> Removes the message from Active
+				// 2) Retry    -> Removes the message from Active & Adds the message to Retry
+				// 3) Archive  -> Removes the message from Active & Adds the message to archive
 				if resErr != nil {
 					p.retryOrKill(ctx, msg, resErr)
 					return
@@ -241,7 +244,7 @@ func (p *processor) requeue(msg *base.TaskMessage) {
 func (p *processor) markAsDone(ctx context.Context, msg *base.TaskMessage) {
 	err := p.broker.Done(msg)
 	if err != nil {
-		errMsg := fmt.Sprintf("Could not remove task id=%s type=%q from %q err: %+v", msg.ID, msg.Type, base.InProgressQueue, err)
+		errMsg := fmt.Sprintf("Could not remove task id=%s type=%q from %q err: %+v", msg.ID, msg.Type, base.ActiveKey(msg.Queue), err)
 		deadline, ok := ctx.Deadline()
 		if !ok {
 			panic("asynq: internal error: missing deadline in context")
@@ -257,13 +260,17 @@ func (p *processor) markAsDone(ctx context.Context, msg *base.TaskMessage) {
 	}
 }

+// SkipRetry is used as a return value from Handler.ProcessTask to indicate that
+// the task should not be retried and should be archived instead.
+var SkipRetry = errors.New("skip retry for the task")
+
 func (p *processor) retryOrKill(ctx context.Context, msg *base.TaskMessage, err error) {
 	if p.errHandler != nil {
 		p.errHandler.HandleError(ctx, NewTask(msg.Type, msg.Payload), err)
 	}
-	if msg.Retried >= msg.Retry {
+	if msg.Retried >= msg.Retry || errors.Is(err, SkipRetry) {
 		p.logger.Warnf("Retry exhausted for task id=%s", msg.ID)
-		p.kill(ctx, msg, err)
+		p.archive(ctx, msg, err)
 	} else {
 		p.retry(ctx, msg, err)
 	}
@@ -274,7 +281,7 @@ func (p *processor) retry(ctx context.Context, msg *base.TaskMessage, e error) {
 	retryAt := time.Now().Add(d)
 	err := p.broker.Retry(msg, retryAt, e.Error())
 	if err != nil {
-		errMsg := fmt.Sprintf("Could not move task id=%s from %q to %q", msg.ID, base.InProgressQueue, base.RetryQueue)
+		errMsg := fmt.Sprintf("Could not move task id=%s from %q to %q", msg.ID, base.ActiveKey(msg.Queue), base.RetryKey(msg.Queue))
 		deadline, ok := ctx.Deadline()
 		if !ok {
 			panic("asynq: internal error: missing deadline in context")
@@ -290,10 +297,10 @@ func (p *processor) retry(ctx context.Context, msg *base.TaskMessage, e error) {
 	}
 }

-func (p *processor) kill(ctx context.Context, msg *base.TaskMessage, e error) {
-	err := p.broker.Kill(msg, e.Error())
+func (p *processor) archive(ctx context.Context, msg *base.TaskMessage, e error) {
+	err := p.broker.Archive(msg, e.Error())
 	if err != nil {
-		errMsg := fmt.Sprintf("Could not move task id=%s from %q to %q", msg.ID, base.InProgressQueue, base.DeadQueue)
+		errMsg := fmt.Sprintf("Could not move task id=%s from %q to %q", msg.ID, base.ActiveKey(msg.Queue), base.ArchivedKey(msg.Queue))
 		deadline, ok := ctx.Deadline()
 		if !ok {
 			panic("asynq: internal error: missing deadline in context")
@@ -301,7 +308,7 @@ func (p *processor) kill(ctx context.Context, msg *base.TaskMessage, e error) {
 		p.logger.Warnf("%s; Will retry syncing", errMsg)
 		p.syncRequestCh <- &syncRequest{
 			fn: func() error {
-				return p.broker.Kill(msg, e.Error())
+				return p.broker.Archive(msg, e.Error())
 			},
 			errMsg:   errMsg,
 			deadline: deadline,
@@ -339,13 +346,26 @@ func (p *processor) queues() []string {
 // perform calls the handler with the given task.
 // If the call returns without panic, it simply returns the value,
 // otherwise, it recovers from panic and returns an error.
-func perform(ctx context.Context, task *Task, h Handler) (err error) {
+func (p *processor) perform(ctx context.Context, task *Task) (err error) {
 	defer func() {
 		if x := recover(); x != nil {
-			err = fmt.Errorf("panic: %v", x)
+			p.logger.Errorf("recovering from panic. See the stack trace below for details:\n%s", string(debug.Stack()))
+			_, file, line, ok := runtime.Caller(1) // skip the first frame (panic itself)
+			if ok && strings.Contains(file, "runtime/") {
+				// The panic came from the runtime, most likely due to incorrect
+				// map/slice usage. The parent frame should have the real trigger.
+				_, file, line, ok = runtime.Caller(2)
+			}
+
+			// Include the file and line number info in the error, if runtime.Caller returned ok.
+			if ok {
+				err = fmt.Errorf("panic [%s:%d]: %v", file, line, x)
+			} else {
+				err = fmt.Errorf("panic: %v", x)
+			}
 		}
 	}()
-	return h.ProcessTask(ctx, task)
+	return p.handler.ProcessTask(ctx, task)
 }

 // uniq dedupes elements and returns a slice of unique names of length l.
--- a/processor_test.go
+++ b/processor_test.go
@@ -42,14 +42,14 @@ func fakeSyncer(syncCh <-chan *syncRequest, done <-chan struct{}) {
 	}
 }

-func TestProcessorSuccess(t *testing.T) {
+func TestProcessorSuccessWithSingleQueue(t *testing.T) {
 	r := setup(t)
 	rdbClient := rdb.NewRDB(r)

-	m1 := h.NewTaskMessage("send_email", nil)
-	m2 := h.NewTaskMessage("gen_thumbnail", nil)
-	m3 := h.NewTaskMessage("reindex", nil)
-	m4 := h.NewTaskMessage("sync", nil)
+	m1 := h.NewTaskMessage("task1", nil)
+	m2 := h.NewTaskMessage("task2", nil)
+	m3 := h.NewTaskMessage("task3", nil)
+	m4 := h.NewTaskMessage("task4", nil)

 	t1 := NewTask(m1.Type, m1.Payload)
 	t2 := NewTask(m2.Type, m2.Payload)
@@ -57,25 +57,25 @@ func TestProcessorSuccess(t *testing.T) {
 	t4 := NewTask(m4.Type, m4.Payload)

 	tests := []struct {
-		enqueued      []*base.TaskMessage // initial default queue state
+		pending       []*base.TaskMessage // initial default queue state
 		incoming      []*base.TaskMessage // tasks to be enqueued during run
 		wantProcessed []*Task             // tasks to be processed at the end
 	}{
 		{
-			enqueued:      []*base.TaskMessage{m1},
+			pending:       []*base.TaskMessage{m1},
 			incoming:      []*base.TaskMessage{m2, m3, m4},
 			wantProcessed: []*Task{t1, t2, t3, t4},
 		},
 		{
-			enqueued:      []*base.TaskMessage{},
+			pending:       []*base.TaskMessage{},
 			incoming:      []*base.TaskMessage{m1},
 			wantProcessed: []*Task{t1},
 		},
 	}

 	for _, tc := range tests {
-		h.FlushDB(t, r)                        // clean up db before each test case.
-		h.SeedEnqueuedQueue(t, r, tc.enqueued) // initialize default queue.
+		h.FlushDB(t, r)                                             // clean up db before each test case.
+		h.SeedPendingQueue(t, r, tc.pending, base.DefaultQueueName) // initialize default queue.

 		// instantiate a new processor
 		var mu sync.Mutex
@@ -96,7 +96,7 @@ func TestProcessorSuccess(t *testing.T) {
 		p := newProcessor(processorParams{
 			logger:          testLogger,
 			broker:          rdbClient,
-			retryDelayFunc:  defaultDelayFunc,
+			retryDelayFunc:  DefaultRetryDelayFunc,
 			syncCh:          syncCh,
 			cancelations:    base.NewCancelations(),
 			concurrency:     10,
@@ -117,9 +117,101 @@ func TestProcessorSuccess(t *testing.T) {
 				t.Fatal(err)
 			}
 		}
-		time.Sleep(2 * time.Second) // wait for two second to allow all enqueued tasks to be processed.
-		if l := r.LLen(base.InProgressQueue).Val(); l != 0 {
-			t.Errorf("%q has %d tasks, want 0", base.InProgressQueue, l)
+		time.Sleep(2 * time.Second) // wait for two second to allow all pending tasks to be processed.
+		if l := r.LLen(base.ActiveKey(base.DefaultQueueName)).Val(); l != 0 {
+			t.Errorf("%q has %d tasks, want 0", base.ActiveKey(base.DefaultQueueName), l)
+		}
+		p.terminate()
+
+		mu.Lock()
+		if diff := cmp.Diff(tc.wantProcessed, processed, sortTaskOpt, cmp.AllowUnexported(Payload{})); diff != "" {
+			t.Errorf("mismatch found in processed tasks; (-want, +got)\n%s", diff)
+		}
+		mu.Unlock()
+	}
+}
+
+func TestProcessorSuccessWithMultipleQueues(t *testing.T) {
+	var (
+		r         = setup(t)
+		rdbClient = rdb.NewRDB(r)
+
+		m1 = h.NewTaskMessage("task1", nil)
+		m2 = h.NewTaskMessage("task2", nil)
+		m3 = h.NewTaskMessageWithQueue("task3", nil, "high")
+		m4 = h.NewTaskMessageWithQueue("task4", nil, "low")
+
+		t1 = NewTask(m1.Type, m1.Payload)
+		t2 = NewTask(m2.Type, m2.Payload)
+		t3 = NewTask(m3.Type, m3.Payload)
+		t4 = NewTask(m4.Type, m4.Payload)
+	)
+
+	tests := []struct {
+		pending       map[string][]*base.TaskMessage
+		queues        []string // list of queues to consume the tasks from
+		wantProcessed []*Task  // tasks to be processed at the end
+	}{
+		{
+			pending: map[string][]*base.TaskMessage{
+				"default": {m1, m2},
+				"high":    {m3},
+				"low":     {m4},
+			},
+			queues:        []string{"default", "high", "low"},
+			wantProcessed: []*Task{t1, t2, t3, t4},
+		},
+	}
+
+	for _, tc := range tests {
+		// Set up test case.
+		h.FlushDB(t, r)
+		h.SeedAllPendingQueues(t, r, tc.pending)
+
+		// Instantiate a new processor.
+		var mu sync.Mutex
+		var processed []*Task
+		handler := func(ctx context.Context, task *Task) error {
+			mu.Lock()
+			defer mu.Unlock()
+			processed = append(processed, task)
+			return nil
+		}
+		starting := make(chan *base.TaskMessage)
+		finished := make(chan *base.TaskMessage)
+		syncCh := make(chan *syncRequest)
+		done := make(chan struct{})
+		defer func() { close(done) }()
+		go fakeHeartbeater(starting, finished, done)
+		go fakeSyncer(syncCh, done)
+		p := newProcessor(processorParams{
+			logger:         testLogger,
+			broker:         rdbClient,
+			retryDelayFunc: DefaultRetryDelayFunc,
+			syncCh:         syncCh,
+			cancelations:   base.NewCancelations(),
+			concurrency:    10,
+			queues: map[string]int{
+				"default": 2,
+				"high":    3,
+				"low":     1,
+			},
+			strictPriority:  false,
+			errHandler:      nil,
+			shutdownTimeout: defaultShutdownTimeout,
+			starting:        starting,
+			finished:        finished,
+		})
+		p.handler = HandlerFunc(handler)
+
+		p.start(&sync.WaitGroup{})
+		// Wait for two second to allow all pending tasks to be processed.
+		time.Sleep(2 * time.Second)
+		// Make sure no messages are stuck in active list.
+		for _, qname := range tc.queues {
+			if l := r.LLen(base.ActiveKey(qname)).Val(); l != 0 {
+				t.Errorf("%q has %d tasks, want 0", base.ActiveKey(qname), l)
+			}
 		}
 		p.terminate()

@@ -140,18 +232,18 @@ func TestProcessTasksWithLargeNumberInPayload(t *testing.T) {
 	t1 := NewTask(m1.Type, m1.Payload)

 	tests := []struct {
-		enqueued      []*base.TaskMessage // initial default queue state
+		pending       []*base.TaskMessage // initial default queue state
 		wantProcessed []*Task             // tasks to be processed at the end
 	}{
 		{
-			enqueued:      []*base.TaskMessage{m1},
+			pending:       []*base.TaskMessage{m1},
 			wantProcessed: []*Task{t1},
 		},
 	}

 	for _, tc := range tests {
-		h.FlushDB(t, r)                        // clean up db before each test case.
-		h.SeedEnqueuedQueue(t, r, tc.enqueued) // initialize default queue.
+		h.FlushDB(t, r)                                             // clean up db before each test case.
+		h.SeedPendingQueue(t, r, tc.pending, base.DefaultQueueName) // initialize default queue.

 		var mu sync.Mutex
 		var processed []*Task
@@ -176,7 +268,7 @@ func TestProcessTasksWithLargeNumberInPayload(t *testing.T) {
 		p := newProcessor(processorParams{
 			logger:          testLogger,
 			broker:          rdbClient,
-			retryDelayFunc:  defaultDelayFunc,
+			retryDelayFunc:  DefaultRetryDelayFunc,
 			syncCh:          syncCh,
 			cancelations:    base.NewCancelations(),
 			concurrency:     10,
@@ -190,9 +282,9 @@ func TestProcessTasksWithLargeNumberInPayload(t *testing.T) {
 		p.handler = HandlerFunc(handler)

 		p.start(&sync.WaitGroup{})
-		time.Sleep(2 * time.Second) // wait for two second to allow all enqueued tasks to be processed.
-		if l := r.LLen(base.InProgressQueue).Val(); l != 0 {
-			t.Errorf("%q has %d tasks, want 0", base.InProgressQueue, l)
+		time.Sleep(2 * time.Second) // wait for two second to allow all pending tasks to be processed.
+		if l := r.LLen(base.ActiveKey(base.DefaultQueueName)).Val(); l != 0 {
+			t.Errorf("%q has %d tasks, want 0", base.ActiveKey(base.DefaultQueueName), l)
 		}
 		p.terminate()

@@ -215,39 +307,74 @@ func TestProcessorRetry(t *testing.T) {
 	m4 := h.NewTaskMessage("sync", nil)

 	errMsg := "something went wrong"
+	wrappedSkipRetry := fmt.Errorf("%s:%w", errMsg, SkipRetry)
 	now := time.Now()

 	tests := []struct {
-		enqueued     []*base.TaskMessage // initial default queue state
+		desc         string              // test description
+		pending      []*base.TaskMessage // initial default queue state
 		incoming     []*base.TaskMessage // tasks to be enqueued during run
 		delay        time.Duration       // retry delay duration
 		handler      Handler             // task handler
 		wait         time.Duration       // wait duration between starting and stopping processor for this test case
-		wantRetry    []h.ZSetEntry       // tasks in retry queue at the end
-		wantDead     []*base.TaskMessage // tasks in dead queue at the end
+		wantRetry    []base.Z            // tasks in retry queue at the end
+		wantArchived []*base.TaskMessage // tasks in archived queue at the end
 		wantErrCount int                 // number of times error handler should be called
 	}{
 		{
-			enqueued: []*base.TaskMessage{m1, m2},
+			desc:     "Should automatically retry errored tasks",
+			pending:  []*base.TaskMessage{m1, m2},
 			incoming: []*base.TaskMessage{m3, m4},
 			delay:    time.Minute,
 			handler: HandlerFunc(func(ctx context.Context, task *Task) error {
 				return fmt.Errorf(errMsg)
 			}),
 			wait: 2 * time.Second,
-			wantRetry: []h.ZSetEntry{
-				{Msg: h.TaskMessageAfterRetry(*m2, errMsg), Score: float64(now.Add(time.Minute).Unix())},
-				{Msg: h.TaskMessageAfterRetry(*m3, errMsg), Score: float64(now.Add(time.Minute).Unix())},
-				{Msg: h.TaskMessageAfterRetry(*m4, errMsg), Score: float64(now.Add(time.Minute).Unix())},
+			wantRetry: []base.Z{
+				{Message: h.TaskMessageAfterRetry(*m2, errMsg), Score: now.Add(time.Minute).Unix()},
+				{Message: h.TaskMessageAfterRetry(*m3, errMsg), Score: now.Add(time.Minute).Unix()},
+				{Message: h.TaskMessageAfterRetry(*m4, errMsg), Score: now.Add(time.Minute).Unix()},
 			},
-			wantDead:     []*base.TaskMessage{h.TaskMessageWithError(*m1, errMsg)},
+			wantArchived: []*base.TaskMessage{h.TaskMessageWithError(*m1, errMsg)},
 			wantErrCount: 4,
 		},
+		{
+			desc:     "Should skip retry errored tasks",
+			pending:  []*base.TaskMessage{m1, m2},
+			incoming: []*base.TaskMessage{},
+			delay:    time.Minute,
+			handler: HandlerFunc(func(ctx context.Context, task *Task) error {
+				return SkipRetry // return SkipRetry without wrapping
+			}),
+			wait:      2 * time.Second,
+			wantRetry: []base.Z{},
+			wantArchived: []*base.TaskMessage{
+				h.TaskMessageWithError(*m1, SkipRetry.Error()),
+				h.TaskMessageWithError(*m2, SkipRetry.Error()),
+			},
+			wantErrCount: 2, // ErrorHandler should still be called with SkipRetry error
+		},
+		{
+			desc:     "Should skip retry errored tasks (with error wrapping)",
+			pending:  []*base.TaskMessage{m1, m2},
+			incoming: []*base.TaskMessage{},
+			delay:    time.Minute,
+			handler: HandlerFunc(func(ctx context.Context, task *Task) error {
+				return wrappedSkipRetry
+			}),
+			wait:      2 * time.Second,
+			wantRetry: []base.Z{},
+			wantArchived: []*base.TaskMessage{
+				h.TaskMessageWithError(*m1, wrappedSkipRetry.Error()),
+				h.TaskMessageWithError(*m2, wrappedSkipRetry.Error()),
+			},
+			wantErrCount: 2, // ErrorHandler should still be called with SkipRetry error
+		},
 	}

 	for _, tc := range tests {
-		h.FlushDB(t, r)                        // clean up db before each test case.
-		h.SeedEnqueuedQueue(t, r, tc.enqueued) // initialize default queue.
+		h.FlushDB(t, r)                                             // clean up db before each test case.
+		h.SeedPendingQueue(t, r, tc.pending, base.DefaultQueueName) // initialize default queue.

 		// instantiate a new processor
 		delayFunc := func(n int, e error, t *Task) time.Duration {
@@ -294,19 +421,19 @@ func TestProcessorRetry(t *testing.T) {
 		time.Sleep(tc.wait) // FIXME: This makes test flaky.
 		p.terminate()

-		cmpOpt := cmpopts.EquateApprox(0, float64(time.Second)) // allow up to a second difference in zset score
-		gotRetry := h.GetRetryEntries(t, r)
+		cmpOpt := h.EquateInt64Approx(1) // allow up to a second difference in zset score
+		gotRetry := h.GetRetryEntries(t, r, base.DefaultQueueName)
 		if diff := cmp.Diff(tc.wantRetry, gotRetry, h.SortZSetEntryOpt, cmpOpt); diff != "" {
-			t.Errorf("mismatch found in %q after running processor; (-want, +got)\n%s", base.RetryQueue, diff)
+			t.Errorf("%s: mismatch found in %q after running processor; (-want, +got)\n%s", tc.desc, base.RetryKey(base.DefaultQueueName), diff)
 		}

-		gotDead := h.GetDeadMessages(t, r)
-		if diff := cmp.Diff(tc.wantDead, gotDead, h.SortMsgOpt); diff != "" {
-			t.Errorf("mismatch found in %q after running processor; (-want, +got)\n%s", base.DeadQueue, diff)
+		gotDead := h.GetArchivedMessages(t, r, base.DefaultQueueName)
+		if diff := cmp.Diff(tc.wantArchived, gotDead, h.SortMsgOpt); diff != "" {
+			t.Errorf("%s: mismatch found in %q after running processor; (-want, +got)\n%s", tc.desc, base.ArchivedKey(base.DefaultQueueName), diff)
 		}

-		if l := r.LLen(base.InProgressQueue).Val(); l != 0 {
-			t.Errorf("%q has %d tasks, want 0", base.InProgressQueue, l)
+		if l := r.LLen(base.ActiveKey(base.DefaultQueueName)).Val(); l != 0 {
+			t.Errorf("%s: %q has %d tasks, want 0", base.ActiveKey(base.DefaultQueueName), tc.desc, l)
 		}

 		if n != tc.wantErrCount {
@@ -351,7 +478,7 @@ func TestProcessorQueues(t *testing.T) {
 		p := newProcessor(processorParams{
 			logger:          testLogger,
 			broker:          nil,
-			retryDelayFunc:  defaultDelayFunc,
+			retryDelayFunc:  DefaultRetryDelayFunc,
 			syncCh:          nil,
 			cancelations:    base.NewCancelations(),
 			concurrency:     10,
@@ -371,36 +498,42 @@ func TestProcessorQueues(t *testing.T) {
 }

 func TestProcessorWithStrictPriority(t *testing.T) {
-	r := setup(t)
-	rdbClient := rdb.NewRDB(r)
+	var (
+		r = setup(t)

-	m1 := h.NewTaskMessage("send_email", nil)
-	m2 := h.NewTaskMessage("send_email", nil)
-	m3 := h.NewTaskMessage("send_email", nil)
-	m4 := h.NewTaskMessage("gen_thumbnail", nil)
-	m5 := h.NewTaskMessage("gen_thumbnail", nil)
-	m6 := h.NewTaskMessage("sync", nil)
-	m7 := h.NewTaskMessage("sync", nil)
+		rdbClient = rdb.NewRDB(r)

-	t1 := NewTask(m1.Type, m1.Payload)
-	t2 := NewTask(m2.Type, m2.Payload)
-	t3 := NewTask(m3.Type, m3.Payload)
-	t4 := NewTask(m4.Type, m4.Payload)
-	t5 := NewTask(m5.Type, m5.Payload)
-	t6 := NewTask(m6.Type, m6.Payload)
-	t7 := NewTask(m7.Type, m7.Payload)
+		m1 = h.NewTaskMessageWithQueue("task1", nil, "critical")
+		m2 = h.NewTaskMessageWithQueue("task2", nil, "critical")
+		m3 = h.NewTaskMessageWithQueue("task3", nil, "critical")
+		m4 = h.NewTaskMessageWithQueue("task4", nil, base.DefaultQueueName)
+		m5 = h.NewTaskMessageWithQueue("task5", nil, base.DefaultQueueName)
+		m6 = h.NewTaskMessageWithQueue("task6", nil, "low")
+		m7 = h.NewTaskMessageWithQueue("task7", nil, "low")
+
+		t1 = NewTask(m1.Type, m1.Payload)
+		t2 = NewTask(m2.Type, m2.Payload)
+		t3 = NewTask(m3.Type, m3.Payload)
+		t4 = NewTask(m4.Type, m4.Payload)
+		t5 = NewTask(m5.Type, m5.Payload)
+		t6 = NewTask(m6.Type, m6.Payload)
+		t7 = NewTask(m7.Type, m7.Payload)
+	)
+	defer r.Close()

 	tests := []struct {
-		enqueued      map[string][]*base.TaskMessage // initial queues state
+		pending       map[string][]*base.TaskMessage // initial queues state
+		queues        []string                       // list of queues to consume tasks from
 		wait          time.Duration                  // wait duration between starting and stopping processor for this test case
 		wantProcessed []*Task                        // tasks to be processed at the end
 	}{
 		{
-			enqueued: map[string][]*base.TaskMessage{
+			pending: map[string][]*base.TaskMessage{
 				base.DefaultQueueName: {m4, m5},
 				"critical":            {m1, m2, m3},
 				"low":                 {m6, m7},
 			},
+			queues:        []string{base.DefaultQueueName, "critical", "low"},
 			wait:          time.Second,
 			wantProcessed: []*Task{t1, t2, t3, t4, t5, t6, t7},
 		},
@@ -408,8 +541,8 @@ func TestProcessorWithStrictPriority(t *testing.T) {

 	for _, tc := range tests {
 		h.FlushDB(t, r) // clean up db before each test case.
-		for qname, msgs := range tc.enqueued {
-			h.SeedEnqueuedQueue(t, r, msgs, qname)
+		for qname, msgs := range tc.pending {
+			h.SeedPendingQueue(t, r, msgs, qname)
 		}

 		// instantiate a new processor
@@ -422,20 +555,22 @@ func TestProcessorWithStrictPriority(t *testing.T) {
 			return nil
 		}
 		queueCfg := map[string]int{
-			"critical":            3,
 			base.DefaultQueueName: 2,
+			"critical":            3,
 			"low":                 1,
 		}
 		starting := make(chan *base.TaskMessage)
 		finished := make(chan *base.TaskMessage)
+		syncCh := make(chan *syncRequest)
 		done := make(chan struct{})
 		defer func() { close(done) }()
 		go fakeHeartbeater(starting, finished, done)
+		go fakeSyncer(syncCh, done)
 		p := newProcessor(processorParams{
 			logger:          testLogger,
 			broker:          rdbClient,
-			retryDelayFunc:  defaultDelayFunc,
-			syncCh:          nil,
+			retryDelayFunc:  DefaultRetryDelayFunc,
+			syncCh:          syncCh,
 			cancelations:    base.NewCancelations(),
 			concurrency:     1, // Set concurrency to 1 to make sure tasks are processed one at a time.
 			queues:          queueCfg,
@@ -449,19 +584,22 @@ func TestProcessorWithStrictPriority(t *testing.T) {

 		p.start(&sync.WaitGroup{})
 		time.Sleep(tc.wait)
+		// Make sure no tasks are stuck in active list.
+		for _, qname := range tc.queues {
+			if l := r.LLen(base.ActiveKey(qname)).Val(); l != 0 {
+				t.Errorf("%q has %d tasks, want 0", base.ActiveKey(qname), l)
+			}
+		}
 		p.terminate()

 		if diff := cmp.Diff(tc.wantProcessed, processed, cmp.AllowUnexported(Payload{})); diff != "" {
 			t.Errorf("mismatch found in processed tasks; (-want, +got)\n%s", diff)
 		}

-		if l := r.LLen(base.InProgressQueue).Val(); l != 0 {
-			t.Errorf("%q has %d tasks, want 0", base.InProgressQueue, l)
-		}
 	}
 }

-func TestPerform(t *testing.T) {
+func TestProcessorPerform(t *testing.T) {
 	tests := []struct {
 		desc    string
 		handler HandlerFunc
@@ -493,9 +631,16 @@ func TestPerform(t *testing.T) {
 			wantErr: true,
 		},
 	}
+	// Note: We don't need to fully initialize the processor since we are only testing
+	// perform method.
+	p := newProcessor(processorParams{
+		logger: testLogger,
+		queues: defaultQueueConfig,
+	})

 	for _, tc := range tests {
-		got := perform(context.Background(), tc.task, tc.handler)
+		p.handler = tc.handler
+		got := p.perform(context.Background(), tc.task)
 		if !tc.wantErr && got != nil {
 			t.Errorf("%s: perform() = %v, want nil", tc.desc, got)
 			continue
--- a/recoverer.go
+++ b/recoverer.go
@@ -16,11 +16,14 @@ import (
 type recoverer struct {
 	logger         *log.Logger
 	broker         base.Broker
-	retryDelayFunc retryDelayFunc
+	retryDelayFunc RetryDelayFunc

 	// channel to communicate back to the long running "recoverer" goroutine.
 	done chan struct{}

+	// list of queues to check for deadline.
+	queues []string
+
 	// poll interval.
 	interval time.Duration
 }
@@ -28,8 +31,9 @@ type recoverer struct {
 type recovererParams struct {
 	logger         *log.Logger
 	broker         base.Broker
+	queues         []string
 	interval       time.Duration
-	retryDelayFunc retryDelayFunc
+	retryDelayFunc RetryDelayFunc
 }

 func newRecoverer(params recovererParams) *recoverer {
@@ -37,6 +41,7 @@ func newRecoverer(params recovererParams) *recoverer {
 		logger:         params.logger,
 		broker:         params.broker,
 		done:           make(chan struct{}),
+		queues:         params.queues,
 		interval:       params.interval,
 		retryDelayFunc: params.retryDelayFunc,
 	}
@@ -62,7 +67,7 @@ func (r *recoverer) start(wg *sync.WaitGroup) {
 			case <-timer.C:
 				// Get all tasks which have expired 30 seconds ago or earlier.
 				deadline := time.Now().Add(-30 * time.Second)
-				msgs, err := r.broker.ListDeadlineExceeded(deadline)
+				msgs, err := r.broker.ListDeadlineExceeded(deadline, r.queues...)
 				if err != nil {
 					r.logger.Warn("recoverer: could not list deadline exceeded tasks")
 					continue
@@ -70,7 +75,7 @@ func (r *recoverer) start(wg *sync.WaitGroup) {
 				const errMsg = "deadline exceeded" // TODO: better error message
 				for _, msg := range msgs {
 					if msg.Retried >= msg.Retry {
-						r.kill(msg, errMsg)
+						r.archive(msg, errMsg)
 					} else {
 						r.retry(msg, errMsg)
 					}
@@ -89,8 +94,8 @@ func (r *recoverer) retry(msg *base.TaskMessage, errMsg string) {
 	}
 }

-func (r *recoverer) kill(msg *base.TaskMessage, errMsg string) {
-	if err := r.broker.Kill(msg, errMsg); err != nil {
-		r.logger.Warnf("recoverer: could not move task to dead queue: %v", err)
+func (r *recoverer) archive(msg *base.TaskMessage, errMsg string) {
+	if err := r.broker.Archive(msg, errMsg); err != nil {
+		r.logger.Warnf("recoverer: could not move task to archive: %v", err)
 	}
 }
--- a/recoverer_test.go
+++ b/recoverer_test.go
@@ -17,12 +17,13 @@ import (

 func TestRecoverer(t *testing.T) {
 	r := setup(t)
+	defer r.Close()
 	rdbClient := rdb.NewRDB(r)

-	t1 := h.NewTaskMessage("task1", nil)
-	t2 := h.NewTaskMessage("task2", nil)
+	t1 := h.NewTaskMessageWithQueue("task1", nil, "default")
+	t2 := h.NewTaskMessageWithQueue("task2", nil, "default")
 	t3 := h.NewTaskMessageWithQueue("task3", nil, "critical")
-	t4 := h.NewTaskMessage("task4", nil)
+	t4 := h.NewTaskMessageWithQueue("task4", nil, "default")
 	t4.Retried = t4.Retry // t4 has reached its max retry count

 	now := time.Now()
@@ -32,107 +33,205 @@ func TestRecoverer(t *testing.T) {
 	oneHourAgo := now.Add(-1 * time.Hour)

 	tests := []struct {
-		desc           string
-		inProgress     []*base.TaskMessage
-		deadlines      []h.ZSetEntry
-		retry          []h.ZSetEntry
-		dead           []h.ZSetEntry
-		wantInProgress []*base.TaskMessage
-		wantDeadlines  []h.ZSetEntry
-		wantRetry      []*base.TaskMessage
-		wantDead       []*base.TaskMessage
+		desc          string
+		inProgress    map[string][]*base.TaskMessage
+		deadlines     map[string][]base.Z
+		retry         map[string][]base.Z
+		archived      map[string][]base.Z
+		wantActive    map[string][]*base.TaskMessage
+		wantDeadlines map[string][]base.Z
+		wantRetry     map[string][]*base.TaskMessage
+		wantArchived  map[string][]*base.TaskMessage
 	}{
 		{
-			desc:       "with one task in-progress",
-			inProgress: []*base.TaskMessage{t1},
-			deadlines: []h.ZSetEntry{
-				{Msg: t1, Score: float64(fiveMinutesAgo.Unix())},
+			desc: "with one active task",
+			inProgress: map[string][]*base.TaskMessage{
+				"default": {t1},
 			},
-			retry:          []h.ZSetEntry{},
-			dead:           []h.ZSetEntry{},
-			wantInProgress: []*base.TaskMessage{},
-			wantDeadlines:  []h.ZSetEntry{},
-			wantRetry: []*base.TaskMessage{
-				h.TaskMessageAfterRetry(*t1, "deadline exceeded"),
+			deadlines: map[string][]base.Z{
+				"default": {{Message: t1, Score: fiveMinutesAgo.Unix()}},
+			},
+			retry: map[string][]base.Z{
+				"default": {},
+			},
+			archived: map[string][]base.Z{
+				"default": {},
+			},
+			wantActive: map[string][]*base.TaskMessage{
+				"default": {},
+			},
+			wantDeadlines: map[string][]base.Z{
+				"default": {},
+			},
+			wantRetry: map[string][]*base.TaskMessage{
+				"default": {h.TaskMessageAfterRetry(*t1, "deadline exceeded")},
+			},
+			wantArchived: map[string][]*base.TaskMessage{
+				"default": {},
 			},
-			wantDead: []*base.TaskMessage{},
 		},
 		{
-			desc:       "with a task with max-retry reached",
-			inProgress: []*base.TaskMessage{t4},
-			deadlines: []h.ZSetEntry{
-				{Msg: t4, Score: float64(fiveMinutesAgo.Unix())},
+			desc: "with a task with max-retry reached",
+			inProgress: map[string][]*base.TaskMessage{
+				"default":  {t4},
+				"critical": {},
+			},
+			deadlines: map[string][]base.Z{
+				"default":  {{Message: t4, Score: fiveMinutesAgo.Unix()}},
+				"critical": {},
+			},
+			retry: map[string][]base.Z{
+				"default":  {},
+				"critical": {},
+			},
+			archived: map[string][]base.Z{
+				"default":  {},
+				"critical": {},
+			},
+			wantActive: map[string][]*base.TaskMessage{
+				"default":  {},
+				"critical": {},
+			},
+			wantDeadlines: map[string][]base.Z{
+				"default":  {},
+				"critical": {},
+			},
+			wantRetry: map[string][]*base.TaskMessage{
+				"default":  {},
+				"critical": {},
+			},
+			wantArchived: map[string][]*base.TaskMessage{
+				"default":  {h.TaskMessageWithError(*t4, "deadline exceeded")},
+				"critical": {},
 			},
-			retry:          []h.ZSetEntry{},
-			dead:           []h.ZSetEntry{},
-			wantInProgress: []*base.TaskMessage{},
-			wantDeadlines:  []h.ZSetEntry{},
-			wantRetry:      []*base.TaskMessage{},
-			wantDead:       []*base.TaskMessage{h.TaskMessageWithError(*t4, "deadline exceeded")},
 		},
 		{
-			desc:       "with multiple tasks in-progress, and one expired",
-			inProgress: []*base.TaskMessage{t1, t2, t3},
-			deadlines: []h.ZSetEntry{
-				{Msg: t1, Score: float64(oneHourAgo.Unix())},
-				{Msg: t2, Score: float64(fiveMinutesFromNow.Unix())},
-				{Msg: t3, Score: float64(oneHourFromNow.Unix())},
+			desc: "with multiple active tasks, and one expired",
+			inProgress: map[string][]*base.TaskMessage{
+				"default":  {t1, t2},
+				"critical": {t3},
 			},
-			retry:          []h.ZSetEntry{},
-			dead:           []h.ZSetEntry{},
-			wantInProgress: []*base.TaskMessage{t2, t3},
-			wantDeadlines: []h.ZSetEntry{
-				{Msg: t2, Score: float64(fiveMinutesFromNow.Unix())},
-				{Msg: t3, Score: float64(oneHourFromNow.Unix())},
+			deadlines: map[string][]base.Z{
+				"default": {
+					{Message: t1, Score: oneHourAgo.Unix()},
+					{Message: t2, Score: fiveMinutesFromNow.Unix()},
+				},
+				"critical": {
+					{Message: t3, Score: oneHourFromNow.Unix()},
+				},
 			},
-			wantRetry: []*base.TaskMessage{
-				h.TaskMessageAfterRetry(*t1, "deadline exceeded"),
+			retry: map[string][]base.Z{
+				"default":  {},
+				"critical": {},
+			},
+			archived: map[string][]base.Z{
+				"default":  {},
+				"critical": {},
+			},
+			wantActive: map[string][]*base.TaskMessage{
+				"default":  {t2},
+				"critical": {t3},
+			},
+			wantDeadlines: map[string][]base.Z{
+				"default":  {{Message: t2, Score: fiveMinutesFromNow.Unix()}},
+				"critical": {{Message: t3, Score: oneHourFromNow.Unix()}},
+			},
+			wantRetry: map[string][]*base.TaskMessage{
+				"default":  {h.TaskMessageAfterRetry(*t1, "deadline exceeded")},
+				"critical": {},
+			},
+			wantArchived: map[string][]*base.TaskMessage{
+				"default":  {},
+				"critical": {},
 			},
-			wantDead: []*base.TaskMessage{},
 		},
 		{
-			desc:       "with multiple expired tasks in-progress",
-			inProgress: []*base.TaskMessage{t1, t2, t3},
-			deadlines: []h.ZSetEntry{
-				{Msg: t1, Score: float64(oneHourAgo.Unix())},
-				{Msg: t2, Score: float64(fiveMinutesAgo.Unix())},
-				{Msg: t3, Score: float64(oneHourFromNow.Unix())},
+			desc: "with multiple expired active tasks",
+			inProgress: map[string][]*base.TaskMessage{
+				"default":  {t1, t2},
+				"critical": {t3},
 			},
-			retry:          []h.ZSetEntry{},
-			dead:           []h.ZSetEntry{},
-			wantInProgress: []*base.TaskMessage{t3},
-			wantDeadlines: []h.ZSetEntry{
-				{Msg: t3, Score: float64(oneHourFromNow.Unix())},
+			deadlines: map[string][]base.Z{
+				"default": {
+					{Message: t1, Score: oneHourAgo.Unix()},
+					{Message: t2, Score: oneHourFromNow.Unix()},
+				},
+				"critical": {
+					{Message: t3, Score: fiveMinutesAgo.Unix()},
+				},
 			},
-			wantRetry: []*base.TaskMessage{
-				h.TaskMessageAfterRetry(*t1, "deadline exceeded"),
-				h.TaskMessageAfterRetry(*t2, "deadline exceeded"),
+			retry: map[string][]base.Z{
+				"default": {},
+				"cricial": {},
+			},
+			archived: map[string][]base.Z{
+				"default": {},
+				"cricial": {},
+			},
+			wantActive: map[string][]*base.TaskMessage{
+				"default":  {t2},
+				"critical": {},
+			},
+			wantDeadlines: map[string][]base.Z{
+				"default": {{Message: t2, Score: oneHourFromNow.Unix()}},
+			},
+			wantRetry: map[string][]*base.TaskMessage{
+				"default":  {h.TaskMessageAfterRetry(*t1, "deadline exceeded")},
+				"critical": {h.TaskMessageAfterRetry(*t3, "deadline exceeded")},
+			},
+			wantArchived: map[string][]*base.TaskMessage{
+				"default":  {},
+				"critical": {},
 			},
-			wantDead: []*base.TaskMessage{},
 		},
 		{
-			desc:           "with empty in-progress queue",
-			inProgress:     []*base.TaskMessage{},
-			deadlines:      []h.ZSetEntry{},
-			retry:          []h.ZSetEntry{},
-			dead:           []h.ZSetEntry{},
-			wantInProgress: []*base.TaskMessage{},
-			wantDeadlines:  []h.ZSetEntry{},
-			wantRetry:      []*base.TaskMessage{},
-			wantDead:       []*base.TaskMessage{},
+			desc: "with empty active queue",
+			inProgress: map[string][]*base.TaskMessage{
+				"default":  {},
+				"critical": {},
+			},
+			deadlines: map[string][]base.Z{
+				"default":  {},
+				"critical": {},
+			},
+			retry: map[string][]base.Z{
+				"default":  {},
+				"critical": {},
+			},
+			archived: map[string][]base.Z{
+				"default":  {},
+				"critical": {},
+			},
+			wantActive: map[string][]*base.TaskMessage{
+				"default":  {},
+				"critical": {},
+			},
+			wantDeadlines: map[string][]base.Z{
+				"default":  {},
+				"critical": {},
+			},
+			wantRetry: map[string][]*base.TaskMessage{
+				"default":  {},
+				"critical": {},
+			},
+			wantArchived: map[string][]*base.TaskMessage{
+				"default":  {},
+				"critical": {},
+			},
 		},
 	}

 	for _, tc := range tests {
 		h.FlushDB(t, r)
-		h.SeedInProgressQueue(t, r, tc.inProgress)
-		h.SeedDeadlines(t, r, tc.deadlines)
-		h.SeedRetryQueue(t, r, tc.retry)
-		h.SeedDeadQueue(t, r, tc.dead)
+		h.SeedAllActiveQueues(t, r, tc.inProgress)
+		h.SeedAllDeadlines(t, r, tc.deadlines)
+		h.SeedAllRetryQueues(t, r, tc.retry)
+		h.SeedAllArchivedQueues(t, r, tc.archived)

 		recoverer := newRecoverer(recovererParams{
 			logger:         testLogger,
 			broker:         rdbClient,
+			queues:         []string{"default", "critical"},
 			interval:       1 * time.Second,
 			retryDelayFunc: func(n int, err error, task *Task) time.Duration { return 30 * time.Second },
 		})
@@ -142,21 +241,29 @@ func TestRecoverer(t *testing.T) {
 		time.Sleep(2 * time.Second)
 		recoverer.terminate()

-		gotInProgress := h.GetInProgressMessages(t, r)
-		if diff := cmp.Diff(tc.wantInProgress, gotInProgress, h.SortMsgOpt); diff != "" {
-			t.Errorf("%s; mismatch found in %q; (-want,+got)\n%s", tc.desc, base.InProgressQueue, diff)
+		for qname, want := range tc.wantActive {
+			gotActive := h.GetActiveMessages(t, r, qname)
+			if diff := cmp.Diff(want, gotActive, h.SortMsgOpt); diff != "" {
+				t.Errorf("%s; mismatch found in %q; (-want,+got)\n%s", tc.desc, base.ActiveKey(qname), diff)
+			}
 		}
-		gotDeadlines := h.GetDeadlinesEntries(t, r)
-		if diff := cmp.Diff(tc.wantDeadlines, gotDeadlines, h.SortZSetEntryOpt); diff != "" {
-			t.Errorf("%s; mismatch found in %q; (-want,+got)\n%s", tc.desc, base.KeyDeadlines, diff)
+		for qname, want := range tc.wantDeadlines {
+			gotDeadlines := h.GetDeadlinesEntries(t, r, qname)
+			if diff := cmp.Diff(want, gotDeadlines, h.SortZSetEntryOpt); diff != "" {
+				t.Errorf("%s; mismatch found in %q; (-want,+got)\n%s", tc.desc, base.DeadlinesKey(qname), diff)
+			}
 		}
-		gotRetry := h.GetRetryMessages(t, r)
-		if diff := cmp.Diff(tc.wantRetry, gotRetry, h.SortMsgOpt); diff != "" {
-			t.Errorf("%s; mismatch found in %q: (-want, +got)\n%s", tc.desc, base.RetryQueue, diff)
+		for qname, want := range tc.wantRetry {
+			gotRetry := h.GetRetryMessages(t, r, qname)
+			if diff := cmp.Diff(want, gotRetry, h.SortMsgOpt); diff != "" {
+				t.Errorf("%s; mismatch found in %q: (-want, +got)\n%s", tc.desc, base.RetryKey(qname), diff)
+			}
 		}
-		gotDead := h.GetDeadMessages(t, r)
-		if diff := cmp.Diff(tc.wantDead, gotDead, h.SortMsgOpt); diff != "" {
-			t.Errorf("%s; mismatch found in %q: (-want, +got)\n%s", tc.desc, base.DeadQueue, diff)
+		for qname, want := range tc.wantArchived {
+			gotDead := h.GetArchivedMessages(t, r, qname)
+			if diff := cmp.Diff(want, gotDead, h.SortMsgOpt); diff != "" {
+				t.Errorf("%s; mismatch found in %q: (-want, +got)\n%s", tc.desc, base.ArchivedKey(qname), diff)
+			}
 		}
 	}
 }
--- a/scheduler.go
+++ b/scheduler.go
@@ -5,64 +5,235 @@
 package asynq

 import (
+	"fmt"
+	"os"
 	"sync"
 	"time"

+	"github.com/google/uuid"
 	"github.com/hibiken/asynq/internal/base"
 	"github.com/hibiken/asynq/internal/log"
+	"github.com/hibiken/asynq/internal/rdb"
+	"github.com/robfig/cron/v3"
 )

-type scheduler struct {
-	logger *log.Logger
-	broker base.Broker
-
-	// channel to communicate back to the long running "scheduler" goroutine.
-	done chan struct{}
-
-	// poll interval on average
-	avgInterval time.Duration
+// A Scheduler kicks off tasks at regular intervals based on the user defined schedule.
+type Scheduler struct {
+	id         string
+	status     *base.ServerStatus
+	logger     *log.Logger
+	client     *Client
+	rdb        *rdb.RDB
+	cron       *cron.Cron
+	location   *time.Location
+	done       chan struct{}
+	wg         sync.WaitGroup
+	errHandler func(task *Task, opts []Option, err error)
 }

-type schedulerParams struct {
-	logger   *log.Logger
-	broker   base.Broker
-	interval time.Duration
-}
+// NewScheduler returns a new Scheduler instance given the redis connection option.
+// The parameter opts is optional, defaults will be used if opts is set to nil
+func NewScheduler(r RedisConnOpt, opts *SchedulerOpts) *Scheduler {
+	if opts == nil {
+		opts = &SchedulerOpts{}
+	}

-func newScheduler(params schedulerParams) *scheduler {
-	return &scheduler{
-		logger:      params.logger,
-		broker:      params.broker,
-		done:        make(chan struct{}),
-		avgInterval: params.interval,
+	logger := log.NewLogger(opts.Logger)
+	loglevel := opts.LogLevel
+	if loglevel == level_unspecified {
+		loglevel = InfoLevel
+	}
+	logger.SetLevel(toInternalLogLevel(loglevel))
+
+	loc := opts.Location
+	if loc == nil {
+		loc = time.UTC
+	}
+
+	return &Scheduler{
+		id:         generateSchedulerID(),
+		status:     base.NewServerStatus(base.StatusIdle),
+		logger:     logger,
+		client:     NewClient(r),
+		rdb:        rdb.NewRDB(createRedisClient(r)),
+		cron:       cron.New(cron.WithLocation(loc)),
+		location:   loc,
+		done:       make(chan struct{}),
+		errHandler: opts.EnqueueErrorHandler,
 	}
 }

-func (s *scheduler) terminate() {
-	s.logger.Debug("Scheduler shutting down...")
-	// Signal the scheduler goroutine to stop polling.
-	s.done <- struct{}{}
+func generateSchedulerID() string {
+	host, err := os.Hostname()
+	if err != nil {
+		host = "unknown-host"
+	}
+	return fmt.Sprintf("%s:%d:%v", host, os.Getpid(), uuid.New())
 }

-// start starts the "scheduler" goroutine.
-func (s *scheduler) start(wg *sync.WaitGroup) {
-	wg.Add(1)
-	go func() {
-		defer wg.Done()
-		for {
-			select {
-			case <-s.done:
-				s.logger.Debug("Scheduler done")
-				return
-			case <-time.After(s.avgInterval):
-				s.exec()
-			}
+// SchedulerOpts specifies scheduler options.
+type SchedulerOpts struct {
+	// Logger specifies the logger used by the scheduler instance.
+	//
+	// If unset, the default logger is used.
+	Logger Logger
+
+	// LogLevel specifies the minimum log level to enable.
+	//
+	// If unset, InfoLevel is used by default.
+	LogLevel LogLevel
+
+	// Location specifies the time zone location.
+	//
+	// If unset, the UTC time zone (time.UTC) is used.
+	Location *time.Location
+
+	// EnqueueErrorHandler gets called when scheduler cannot enqueue a registered task
+	// due to an error.
+	EnqueueErrorHandler func(task *Task, opts []Option, err error)
+}
+
+// enqueueJob encapsulates the job of enqueing a task and recording the event.
+type enqueueJob struct {
+	id         uuid.UUID
+	cronspec   string
+	task       *Task
+	opts       []Option
+	location   *time.Location
+	logger     *log.Logger
+	client     *Client
+	rdb        *rdb.RDB
+	errHandler func(task *Task, opts []Option, err error)
+}
+
+func (j *enqueueJob) Run() {
+	res, err := j.client.Enqueue(j.task, j.opts...)
+	if err != nil {
+		j.logger.Errorf("scheduler could not enqueue a task %+v: %v", j.task, err)
+		if j.errHandler != nil {
+			j.errHandler(j.task, j.opts, err)
 		}
-	}()
-}
-
-func (s *scheduler) exec() {
-	if err := s.broker.CheckAndEnqueue(); err != nil {
-		s.logger.Errorf("Could not enqueue scheduled tasks: %v", err)
+		return
+	}
+	j.logger.Debugf("scheduler enqueued a task: %+v", res)
+	event := &base.SchedulerEnqueueEvent{
+		TaskID:     res.ID,
+		EnqueuedAt: res.EnqueuedAt.In(j.location),
+	}
+	err = j.rdb.RecordSchedulerEnqueueEvent(j.id.String(), event)
+	if err != nil {
+		j.logger.Errorf("scheduler could not record enqueue event of enqueued task %+v: %v", j.task, err)
 	}
 }
+
+// Register registers a task to be enqueued on the given schedule specified by the cronspec.
+// It returns an ID of the newly registered entry.
+func (s *Scheduler) Register(cronspec string, task *Task, opts ...Option) (entryID string, err error) {
+	job := &enqueueJob{
+		id:         uuid.New(),
+		cronspec:   cronspec,
+		task:       task,
+		opts:       opts,
+		location:   s.location,
+		client:     s.client,
+		rdb:        s.rdb,
+		logger:     s.logger,
+		errHandler: s.errHandler,
+	}
+	if _, err = s.cron.AddJob(cronspec, job); err != nil {
+		return "", err
+	}
+	return job.id.String(), nil
+}
+
+// Run starts the scheduler until an os signal to exit the program is received.
+// It returns an error if scheduler is already running or has been stopped.
+func (s *Scheduler) Run() error {
+	if err := s.Start(); err != nil {
+		return err
+	}
+	s.waitForSignals()
+	return s.Stop()
+}
+
+// Start starts the scheduler.
+// It returns an error if the scheduler is already running or has been stopped.
+func (s *Scheduler) Start() error {
+	switch s.status.Get() {
+	case base.StatusRunning:
+		return fmt.Errorf("asynq: the scheduler is already running")
+	case base.StatusStopped:
+		return fmt.Errorf("asynq: the scheduler has already been stopped")
+	}
+	s.logger.Info("Scheduler starting")
+	s.logger.Infof("Scheduler timezone is set to %v", s.location)
+	s.cron.Start()
+	s.wg.Add(1)
+	go s.runHeartbeater()
+	s.status.Set(base.StatusRunning)
+	return nil
+}
+
+// Stop stops the scheduler.
+// It returns an error if the scheduler is not currently running.
+func (s *Scheduler) Stop() error {
+	if s.status.Get() != base.StatusRunning {
+		return fmt.Errorf("asynq: the scheduler is not running")
+	}
+	s.logger.Info("Scheduler shutting down")
+	close(s.done) // signal heartbeater to stop
+	ctx := s.cron.Stop()
+	<-ctx.Done()
+	s.wg.Wait()
+
+	s.client.Close()
+	s.rdb.Close()
+	s.status.Set(base.StatusStopped)
+	s.logger.Info("Scheduler stopped")
+	return nil
+}
+
+func (s *Scheduler) runHeartbeater() {
+	defer s.wg.Done()
+	ticker := time.NewTicker(5 * time.Second)
+	for {
+		select {
+		case <-s.done:
+			s.logger.Debugf("Scheduler heatbeater shutting down")
+			s.rdb.ClearSchedulerEntries(s.id)
+			return
+		case <-ticker.C:
+			s.beat()
+		}
+	}
+}
+
+// beat writes a snapshot of entries to redis.
+func (s *Scheduler) beat() {
+	var entries []*base.SchedulerEntry
+	for _, entry := range s.cron.Entries() {
+		job := entry.Job.(*enqueueJob)
+		e := &base.SchedulerEntry{
+			ID:      job.id.String(),
+			Spec:    job.cronspec,
+			Type:    job.task.Type,
+			Payload: job.task.Payload.data,
+			Opts:    stringifyOptions(job.opts),
+			Next:    entry.Next,
+			Prev:    entry.Prev,
+		}
+		entries = append(entries, e)
+	}
+	s.logger.Debugf("Writing entries %v", entries)
+	if err := s.rdb.WriteSchedulerEntries(s.id, entries, 5*time.Second); err != nil {
+		s.logger.Warnf("Scheduler could not write heartbeat data: %v", err)
+	}
+}
+
+func stringifyOptions(opts []Option) []string {
+	var res []string
+	for _, opt := range opts {
+		res = append(res, opt.String())
+	}
+	return res
+}
--- a/scheduler_test.go
+++ b/scheduler_test.go
@@ -10,88 +10,109 @@ import (
 	"time"

 	"github.com/google/go-cmp/cmp"
-	h "github.com/hibiken/asynq/internal/asynqtest"
+	"github.com/hibiken/asynq/internal/asynqtest"
 	"github.com/hibiken/asynq/internal/base"
-	"github.com/hibiken/asynq/internal/rdb"
 )

 func TestScheduler(t *testing.T) {
-	r := setup(t)
-	rdbClient := rdb.NewRDB(r)
-	const pollInterval = time.Second
-	s := newScheduler(schedulerParams{
-		logger:   testLogger,
-		broker:   rdbClient,
-		interval: pollInterval,
-	})
-	t1 := h.NewTaskMessage("gen_thumbnail", nil)
-	t2 := h.NewTaskMessage("send_email", nil)
-	t3 := h.NewTaskMessage("reindex", nil)
-	t4 := h.NewTaskMessage("sync", nil)
-	now := time.Now()
-
 	tests := []struct {
-		initScheduled []h.ZSetEntry       // scheduled queue initial state
-		initRetry     []h.ZSetEntry       // retry queue initial state
-		initQueue     []*base.TaskMessage // default queue initial state
-		wait          time.Duration       // wait duration before checking for final state
-		wantScheduled []*base.TaskMessage // schedule queue final state
-		wantRetry     []*base.TaskMessage // retry queue final state
-		wantQueue     []*base.TaskMessage // default queue final state
+		cronspec string
+		task     *Task
+		opts     []Option
+		wait     time.Duration
+		queue    string
+		want     []*base.TaskMessage
 	}{
 		{
-			initScheduled: []h.ZSetEntry{
-				{Msg: t1, Score: float64(now.Add(time.Hour).Unix())},
-				{Msg: t2, Score: float64(now.Add(-2 * time.Second).Unix())},
+			cronspec: "@every 3s",
+			task:     NewTask("task1", nil),
+			opts:     []Option{MaxRetry(10)},
+			wait:     10 * time.Second,
+			queue:    "default",
+			want: []*base.TaskMessage{
+				{
+					Type:    "task1",
+					Payload: nil,
+					Retry:   10,
+					Timeout: int64(defaultTimeout.Seconds()),
+					Queue:   "default",
+				},
+				{
+					Type:    "task1",
+					Payload: nil,
+					Retry:   10,
+					Timeout: int64(defaultTimeout.Seconds()),
+					Queue:   "default",
+				},
+				{
+					Type:    "task1",
+					Payload: nil,
+					Retry:   10,
+					Timeout: int64(defaultTimeout.Seconds()),
+					Queue:   "default",
+				},
 			},
-			initRetry: []h.ZSetEntry{
-				{Msg: t3, Score: float64(time.Now().Add(-500 * time.Millisecond).Unix())},
-			},
-			initQueue:     []*base.TaskMessage{t4},
-			wait:          pollInterval * 2,
-			wantScheduled: []*base.TaskMessage{t1},
-			wantRetry:     []*base.TaskMessage{},
-			wantQueue:     []*base.TaskMessage{t2, t3, t4},
-		},
-		{
-			initScheduled: []h.ZSetEntry{
-				{Msg: t1, Score: float64(now.Unix())},
-				{Msg: t2, Score: float64(now.Add(-2 * time.Second).Unix())},
-				{Msg: t3, Score: float64(now.Add(-500 * time.Millisecond).Unix())},
-			},
-			initRetry:     []h.ZSetEntry{},
-			initQueue:     []*base.TaskMessage{t4},
-			wait:          pollInterval * 2,
-			wantScheduled: []*base.TaskMessage{},
-			wantRetry:     []*base.TaskMessage{},
-			wantQueue:     []*base.TaskMessage{t1, t2, t3, t4},
 		},
 	}

+	r := setup(t)
+
 	for _, tc := range tests {
-		h.FlushDB(t, r)                              // clean up db before each test case.
-		h.SeedScheduledQueue(t, r, tc.initScheduled) // initialize scheduled queue
-		h.SeedRetryQueue(t, r, tc.initRetry)         // initialize retry queue
-		h.SeedEnqueuedQueue(t, r, tc.initQueue)      // initialize default queue
+		scheduler := NewScheduler(getRedisConnOpt(t), nil)
+		if _, err := scheduler.Register(tc.cronspec, tc.task, tc.opts...); err != nil {
+			t.Fatal(err)
+		}

-		var wg sync.WaitGroup
-		s.start(&wg)
+		if err := scheduler.Start(); err != nil {
+			t.Fatal(err)
+		}
 		time.Sleep(tc.wait)
-		s.terminate()
-
-		gotScheduled := h.GetScheduledMessages(t, r)
-		if diff := cmp.Diff(tc.wantScheduled, gotScheduled, h.SortMsgOpt); diff != "" {
-			t.Errorf("mismatch found in %q after running scheduler: (-want, +got)\n%s", base.ScheduledQueue, diff)
+		if err := scheduler.Stop(); err != nil {
+			t.Fatal(err)
 		}

-		gotRetry := h.GetRetryMessages(t, r)
-		if diff := cmp.Diff(tc.wantRetry, gotRetry, h.SortMsgOpt); diff != "" {
-			t.Errorf("mismatch found in %q after running scheduler: (-want, +got)\n%s", base.RetryQueue, diff)
-		}
-
-		gotEnqueued := h.GetEnqueuedMessages(t, r)
-		if diff := cmp.Diff(tc.wantQueue, gotEnqueued, h.SortMsgOpt); diff != "" {
-			t.Errorf("mismatch found in %q after running scheduler: (-want, +got)\n%s", base.DefaultQueue, diff)
+		got := asynqtest.GetPendingMessages(t, r, tc.queue)
+		if diff := cmp.Diff(tc.want, got, asynqtest.IgnoreIDOpt); diff != "" {
+			t.Errorf("mismatch found in queue %q: (-want,+got)\n%s", tc.queue, diff)
 		}
 	}
 }
+
+func TestSchedulerWhenRedisDown(t *testing.T) {
+	var (
+		mu      sync.Mutex
+		counter int
+	)
+	errorHandler := func(task *Task, opts []Option, err error) {
+		mu.Lock()
+		counter++
+		mu.Unlock()
+	}
+
+	// Connect to non-existent redis instance to simulate a redis server being down.
+	scheduler := NewScheduler(
+		RedisClientOpt{Addr: ":9876"},
+		&SchedulerOpts{EnqueueErrorHandler: errorHandler},
+	)
+
+	task := NewTask("test", nil)
+
+	if _, err := scheduler.Register("@every 3s", task); err != nil {
+		t.Fatal(err)
+	}
+
+	if err := scheduler.Start(); err != nil {
+		t.Fatal(err)
+	}
+	// Scheduler should attempt to enqueue the task three times (every 3s).
+	time.Sleep(10 * time.Second)
+	if err := scheduler.Stop(); err != nil {
+		t.Fatal(err)
+	}
+
+	mu.Lock()
+	if counter != 3 {
+		t.Errorf("EnqueueErrorHandler was called %d times, want 3", counter)
+	}
+	mu.Unlock()
+}
--- a/server.go
+++ b/server.go
@@ -20,18 +20,17 @@ import (
 	"github.com/hibiken/asynq/internal/rdb"
 )

-// Server is responsible for managing the background-task processing.
+// Server is responsible for managing the task processing.
 //
 // Server pulls tasks off queues and processes them.
-// If the processing of a task is unsuccessful, server will
-// schedule it for a retry.
+// If the processing of a task is unsuccessful, server will schedule it for a retry.
 // A task will be retried until either the task gets processed successfully
 // or until it reaches its max retry count.
 //
-// If a task exhausts its retries, it will be moved to the "dead" queue and
-// will be kept in the queue for some time until a certain condition is met
-// (e.g., queue size reaches a certain limit, or the task has been in the
-// queue for a certain amount of time).
+// If a task exhausts its retries, it will be moved to the archive and
+// will be kept in the archive for some time until a certain condition is met
+// (e.g., archive size reaches a certain limit, or the task has been in the
+// archive for a certain amount of time).
 type Server struct {
 	logger *log.Logger

@@ -40,13 +39,14 @@ type Server struct {
 	status *base.ServerStatus

 	// wait group to wait for all goroutines to finish.
-	wg          sync.WaitGroup
-	scheduler   *scheduler
-	processor   *processor
-	syncer      *syncer
-	heartbeater *heartbeater
-	subscriber  *subscriber
-	recoverer   *recoverer
+	wg            sync.WaitGroup
+	forwarder     *forwarder
+	processor     *processor
+	syncer        *syncer
+	heartbeater   *heartbeater
+	subscriber    *subscriber
+	recoverer     *recoverer
+	healthchecker *healthchecker
 }

 // Config specifies the server's background-task processing behavior.
@@ -60,11 +60,7 @@ type Config struct {
 	// Function to calculate retry delay for a failed task.
 	//
 	// By default, it uses exponential backoff algorithm to calculate the delay.
-	//
-	// n is the number of times the task has been retried.
-	// e is the error returned by the task handler.
-	// t is the task in question.
-	RetryDelayFunc func(n int, e error, t *Task) time.Duration
+	RetryDelayFunc RetryDelayFunc

 	// List of queues to process with given priority value. Keys are the names of the
 	// queues and values are associated priority value.
@@ -74,11 +70,13 @@ type Config struct {
 	// Priority is treated as follows to avoid starving low priority queues.
 	//
 	// Example:
-	// Queues: map[string]int{
-	//     "critical": 6,
-	//     "default":  3,
-	//     "low":      1,
-	// }
+	//
+	//     Queues: map[string]int{
+	//         "critical": 6,
+	//         "default":  3,
+	//         "low":      1,
+	//     }
+	//
 	// With the above config and given that all queues are not empty, the tasks
 	// in "critical", "default", "low" should be processed 60%, 30%, 10% of
 	// the time respectively.
@@ -98,14 +96,17 @@ type Config struct {
 	// HandleError is invoked only if the task handler returns a non-nil error.
 	//
 	// Example:
-	// func reportError(task *asynq.Task, err error, retried, maxRetry int) {
-	// 	   if retried >= maxRetry {
-	//         err = fmt.Errorf("retry exhausted for task %s: %w", task.Type, err)
-	// 	   }
-	//     errorReportingService.Notify(err)
-	// })
 	//
-	// ErrorHandler: asynq.ErrorHandlerFunc(reportError)
+	//     func reportError(ctx context, task *asynq.Task, err error) {
+	//         retried, _ := asynq.GetRetryCount(ctx)
+	//         maxRetry, _ := asynq.GetMaxRetry(ctx)
+	//     	   if retried >= maxRetry {
+	//             err = fmt.Errorf("retry exhausted for task %s: %w", task.Type, err)
+	//     	   }
+	//         errorReportingService.Notify(err)
+	//     })
+	//
+	//     ErrorHandler: asynq.ErrorHandlerFunc(reportError)
 	ErrorHandler ErrorHandler

 	// Logger specifies the logger used by the server instance.
@@ -123,6 +124,15 @@ type Config struct {
 	//
 	// If unset or zero, default timeout of 8 seconds is used.
 	ShutdownTimeout time.Duration
+
+	// HealthCheckFunc is called periodically with any errors encountered during ping to the
+	// connected redis server.
+	HealthCheckFunc func(error)
+
+	// HealthCheckInterval specifies the interval between healthchecks.
+	//
+	// If unset or zero, the interval is set to 15 seconds.
+	HealthCheckInterval time.Duration
 }

 // An ErrorHandler handles an error occured during task processing.
@@ -139,6 +149,14 @@ func (fn ErrorHandlerFunc) HandleError(ctx context.Context, task *Task, err erro
 	fn(ctx, task, err)
 }

+// RetryDelayFunc calculates the retry delay duration for a failed task given
+// the retry count, error, and the task.
+//
+// n is the number of times the task has been retried.
+// e is the error returned by the task handler.
+// t is the task in question.
+type RetryDelayFunc func(n int, e error, t *Task) time.Duration
+
 // Logger supports logging at various log levels.
 type Logger interface {
 	// Debug logs a message at Debug level.
@@ -239,9 +257,11 @@ func toInternalLogLevel(l LogLevel) log.Level {
 	panic(fmt.Sprintf("asynq: unexpected log level: %v", l))
 }

-// Formula taken from https://github.com/mperham/sidekiq.
-func defaultDelayFunc(n int, e error, t *Task) time.Duration {
+// DefaultRetryDelayFunc is the default RetryDelayFunc used if one is not specified in Config.
+// It uses exponential back-off strategy to calculate the retry delay.
+func DefaultRetryDelayFunc(n int, e error, t *Task) time.Duration {
 	r := rand.New(rand.NewSource(time.Now().UnixNano()))
+	// Formula taken from https://github.com/mperham/sidekiq.
 	s := int(math.Pow(float64(n), 4)) + 15 + (r.Intn(30) * (n + 1))
 	return time.Duration(s) * time.Second
 }
@@ -250,7 +270,11 @@ var defaultQueueConfig = map[string]int{
 	base.DefaultQueueName: 1,
 }

-const defaultShutdownTimeout = 8 * time.Second
+const (
+	defaultShutdownTimeout = 8 * time.Second
+
+	defaultHealthCheckInterval = 15 * time.Second
+)

 // NewServer returns a new Server given a redis connection option
 // and background processing configuration.
@@ -261,7 +285,7 @@ func NewServer(r RedisConnOpt, cfg Config) *Server {
 	}
 	delayFunc := cfg.RetryDelayFunc
 	if delayFunc == nil {
-		delayFunc = defaultDelayFunc
+		delayFunc = DefaultRetryDelayFunc
 	}
 	queues := make(map[string]int)
 	for qname, p := range cfg.Queues {
@@ -272,10 +296,18 @@ func NewServer(r RedisConnOpt, cfg Config) *Server {
 	if len(queues) == 0 {
 		queues = defaultQueueConfig
 	}
+	var qnames []string
+	for q := range queues {
+		qnames = append(qnames, q)
+	}
 	shutdownTimeout := cfg.ShutdownTimeout
 	if shutdownTimeout == 0 {
 		shutdownTimeout = defaultShutdownTimeout
 	}
+	healthcheckInterval := cfg.HealthCheckInterval
+	if healthcheckInterval == 0 {
+		healthcheckInterval = defaultHealthCheckInterval
+	}
 	logger := log.NewLogger(cfg.Logger)
 	loglevel := cfg.LogLevel
 	if loglevel == level_unspecified {
@@ -306,9 +338,10 @@ func NewServer(r RedisConnOpt, cfg Config) *Server {
 		starting:       starting,
 		finished:       finished,
 	})
-	scheduler := newScheduler(schedulerParams{
+	forwarder := newForwarder(forwarderParams{
 		logger:   logger,
 		broker:   rdb,
+		queues:   qnames,
 		interval: 5 * time.Second,
 	})
 	subscriber := newSubscriber(subscriberParams{
@@ -334,18 +367,26 @@ func NewServer(r RedisConnOpt, cfg Config) *Server {
 		logger:         logger,
 		broker:         rdb,
 		retryDelayFunc: delayFunc,
+		queues:         qnames,
 		interval:       1 * time.Minute,
 	})
+	healthchecker := newHealthChecker(healthcheckerParams{
+		logger:          logger,
+		broker:          rdb,
+		interval:        healthcheckInterval,
+		healthcheckFunc: cfg.HealthCheckFunc,
+	})
 	return &Server{
-		logger:      logger,
-		broker:      rdb,
-		status:      status,
-		scheduler:   scheduler,
-		processor:   processor,
-		syncer:      syncer,
-		heartbeater: heartbeater,
-		subscriber:  subscriber,
-		recoverer:   recoverer,
+		logger:        logger,
+		broker:        rdb,
+		status:        status,
+		forwarder:     forwarder,
+		processor:     processor,
+		syncer:        syncer,
+		heartbeater:   heartbeater,
+		subscriber:    subscriber,
+		recoverer:     recoverer,
+		healthchecker: healthchecker,
 	}
 }

@@ -356,6 +397,9 @@ func NewServer(r RedisConnOpt, cfg Config) *Server {
 //
 // If ProcessTask return a non-nil error or panics, the task
 // will be retried after delay.
+// One exception to this rule is when ProcessTask returns SkipRetry error.
+// If the returned error is SkipRetry or the error wraps SkipRetry, retry is
+// skipped and task will be archived instead.
 type Handler interface {
 	ProcessTask(context.Context, *Task) error
 }
@@ -413,10 +457,11 @@ func (srv *Server) Start(handler Handler) error {
 	srv.logger.Info("Starting processing")

 	srv.heartbeater.start(&srv.wg)
+	srv.healthchecker.start(&srv.wg)
 	srv.subscriber.start(&srv.wg)
 	srv.syncer.start(&srv.wg)
 	srv.recoverer.start(&srv.wg)
-	srv.scheduler.start(&srv.wg)
+	srv.forwarder.start(&srv.wg)
 	srv.processor.start(&srv.wg)
 	return nil
 }
@@ -437,11 +482,12 @@ func (srv *Server) Stop() {
 	// Sender goroutines should be terminated before the receiver goroutines.
 	// processor -> syncer (via syncCh)
 	// processor -> heartbeater (via starting, finished channels)
-	srv.scheduler.terminate()
+	srv.forwarder.terminate()
 	srv.processor.terminate()
 	srv.recoverer.terminate()
 	srv.syncer.terminate()
 	srv.subscriber.terminate()
+	srv.healthchecker.terminate()
 	srv.heartbeater.terminate()

 	srv.wg.Wait()
--- a/server_test.go
+++ b/server_test.go
@@ -21,12 +21,10 @@ func TestServer(t *testing.T) {
 	ignoreOpt := goleak.IgnoreTopFunction("github.com/go-redis/redis/v7/internal/pool.(*ConnPool).reaper")
 	defer goleak.VerifyNoLeaks(t, ignoreOpt)

-	r := &RedisClientOpt{
-		Addr: "localhost:6379",
-		DB:   15,
-	}
-	c := NewClient(r)
-	srv := NewServer(r, Config{
+	redisConnOpt := getRedisConnOpt(t)
+	c := NewClient(redisConnOpt)
+	defer c.Close()
+	srv := NewServer(redisConnOpt, Config{
 		Concurrency: 10,
 		LogLevel:    testLogLevel,
 	})
@@ -46,7 +44,7 @@ func TestServer(t *testing.T) {
 		t.Errorf("could not enqueue a task: %v", err)
 	}

-	_, err = c.EnqueueAt(time.Now().Add(time.Hour), NewTask("send_email", map[string]interface{}{"recipient_id": 456}))
+	_, err = c.Enqueue(NewTask("send_email", map[string]interface{}{"recipient_id": 456}), ProcessIn(1*time.Hour))
 	if err != nil {
 		t.Errorf("could not enqueue a task: %v", err)
 	}
@@ -129,7 +127,7 @@ func TestServerWithRedisDown(t *testing.T) {
 	testBroker := testbroker.NewTestBroker(r)
 	srv := NewServer(RedisClientOpt{Addr: ":6379"}, Config{LogLevel: testLogLevel})
 	srv.broker = testBroker
-	srv.scheduler.broker = testBroker
+	srv.forwarder.broker = testBroker
 	srv.heartbeater.broker = testBroker
 	srv.processor.broker = testBroker
 	srv.subscriber.broker = testBroker
@@ -159,14 +157,15 @@ func TestServerWithFlakyBroker(t *testing.T) {
 	}()
 	r := rdb.NewRDB(setup(t))
 	testBroker := testbroker.NewTestBroker(r)
-	srv := NewServer(RedisClientOpt{Addr: redisAddr, DB: redisDB}, Config{LogLevel: testLogLevel})
+	redisConnOpt := getRedisConnOpt(t)
+	srv := NewServer(redisConnOpt, Config{LogLevel: testLogLevel})
 	srv.broker = testBroker
-	srv.scheduler.broker = testBroker
+	srv.forwarder.broker = testBroker
 	srv.heartbeater.broker = testBroker
 	srv.processor.broker = testBroker
 	srv.subscriber.broker = testBroker

-	c := NewClient(RedisClientOpt{Addr: redisAddr, DB: redisDB})
+	c := NewClient(redisConnOpt)

 	h := func(ctx context.Context, task *Task) error {
 		// force task retry.
@@ -191,7 +190,7 @@ func TestServerWithFlakyBroker(t *testing.T) {
 		if err != nil {
 			t.Fatal(err)
 		}
-		_, err = c.EnqueueIn(time.Duration(i)*time.Second, NewTask("scheduled", nil))
+		_, err = c.Enqueue(NewTask("scheduled", nil), ProcessIn(time.Duration(i)*time.Second))
 		if err != nil {
 			t.Fatal(err)
 		}
--- a/signals_unix.go
+++ b/signals_unix.go
@@ -28,3 +28,10 @@ func (srv *Server) waitForSignals() {
 		break
 	}
 }
+
+func (s *Scheduler) waitForSignals() {
+	s.logger.Info("Send signal TERM or INT to stop the scheduler")
+	sigs := make(chan os.Signal, 1)
+	signal.Notify(sigs, unix.SIGTERM, unix.SIGINT)
+	<-sigs
+}
--- a/signals_windows.go
+++ b/signals_windows.go
@@ -20,3 +20,10 @@ func (srv *Server) waitForSignals() {
 	signal.Notify(sigs, windows.SIGTERM, windows.SIGINT)
 	<-sigs
 }
+
+func (s *Scheduler) waitForSignals() {
+	s.logger.Info("Send signal TERM or INT to stop the scheduler")
+	sigs := make(chan os.Signal, 1)
+	signal.Notify(sigs, windows.SIGTERM, windows.SIGINT)
+	<-sigs
+}
--- a/subscriber.go
+++ b/subscriber.go
@@ -20,7 +20,7 @@ type subscriber struct {
 	// channel to communicate back to the long running "subscriber" goroutine.
 	done chan struct{}

-	// cancelations hold cancel functions for all in-progress tasks.
+	// cancelations hold cancel functions for all active tasks.
 	cancelations *base.Cancelations

 	// time to wait before retrying to connect to redis.
--- a/subscriber_test.go
+++ b/subscriber_test.go
@@ -16,6 +16,7 @@ import (

 func TestSubscriber(t *testing.T) {
 	r := setup(t)
+	defer r.Close()
 	rdbClient := rdb.NewRDB(r)

 	tests := []struct {
@@ -76,6 +77,7 @@ func TestSubscriberWithRedisDown(t *testing.T) {
 		}
 	}()
 	r := rdb.NewRDB(setup(t))
+	defer r.Close()
 	testBroker := testbroker.NewTestBroker(r)

 	cancelations := base.NewCancelations()
--- a/syncer_test.go
+++ b/syncer_test.go
@@ -22,8 +22,9 @@ func TestSyncer(t *testing.T) {
 		h.NewTaskMessage("gen_thumbnail", nil),
 	}
 	r := setup(t)
+	defer r.Close()
 	rdbClient := rdb.NewRDB(r)
-	h.SeedInProgressQueue(t, r, inProgress)
+	h.SeedActiveQueue(t, r, inProgress, base.DefaultQueueName)

 	const interval = time.Second
 	syncRequestCh := make(chan *syncRequest)
@@ -48,9 +49,9 @@ func TestSyncer(t *testing.T) {

 	time.Sleep(2 * interval) // ensure that syncer runs at least once

-	gotInProgress := h.GetInProgressMessages(t, r)
-	if l := len(gotInProgress); l != 0 {
-		t.Errorf("%q has length %d; want 0", base.InProgressQueue, l)
+	gotActive := h.GetActiveMessages(t, r, base.DefaultQueueName)
+	if l := len(gotActive); l != 0 {
+		t.Errorf("%q has length %d; want 0", base.ActiveKey(base.DefaultQueueName), l)
 	}
 }

--- a/tools/asynq/README.md
+++ b/tools/asynq/README.md
@@ -1,20 +1,11 @@
 # Asynq CLI

-Asynq CLI is a command line tool to monitor the tasks managed by `asynq` package.
+Asynq CLI is a command line tool to monitor the queues and tasks managed by `asynq` package.

 ## Table of Contents

 - [Installation](#installation)
- [Quick Start](#quick-start)
-  - [Stats](#stats)
-  - [History](#history)
-  - [Servers](#servers)
-  - [List](#list)
-  - [Enqueue](#enqueue)
-  - [Delete](#delete)
-  - [Kill](#kill)
-  - [Cancel](#cancel)
-  - [Pause](#pause)
+- [Usage](#usage)
 - [Config File](#config-file)

 ## Installation
@@ -25,144 +16,41 @@ In order to use the tool, compile it using the following command:

 This will create the asynq executable under your `$GOPATH/bin` directory.

-## Quickstart
+## Usage

-The tool has a few commands to inspect the state of tasks and queues.
+### Commands

-Run `asynq help` to see all the available commands.
+To view details on any command, use `asynq help <command> <subcommand>`.
+
+- `asynq stats`
+- `asynq queue [ls inspect history rm pause unpause]`
+- `asynq task [ls cancel delete archive run delete-all archive-all run-all]`
+- `asynq server [ls]`
+
+### Global flags

 Asynq CLI needs to connect to a redis-server to inspect the state of queues and tasks. Use flags to specify the options to connect to the redis-server used by your application.
+To connect to a redis cluster, pass `--cluster` and `--cluster_addrs` flags.

 By default, CLI will try to connect to a redis server running at `localhost:6379`.

-### Stats
+```
+      --config string          config file to set flag defaut values (default is $HOME/.asynq.yaml)
+  -n, --db int                 redis database number (default is 0)
+  -h, --help                   help for asynq
+  -p, --password string        password to use when connecting to redis server
+  -u, --uri string             redis server URI (default "127.0.0.1:6379")

-Stats command gives the overview of the current state of tasks and queues. You can run it in conjunction with `watch` command to repeatedly run `stats`.
-
-Example:
-
-    watch -n 3 asynq stats
-
-This will run `asynq stats` command every 3 seconds.
-
-![Gif](/docs/assets/asynq_stats.gif)
-
-### History
-
-History command shows the number of processed and failed tasks from the last x days.
-
-By default, it shows the stats from the last 10 days. Use `--days` to specify the number of days.
-
-Example:
-
-    asynq history --days=30
-
-![Gif](/docs/assets/asynq_history.gif)
-
-### Servers
-
-Servers command shows the list of running worker servers pulling tasks from the given redis instance.
-
-Example:
-
-    asynq servers
-
-### List
-
-List command shows all tasks in the specified state in a table format
-
-Example:
-
-    asynq ls retry
-    asynq ls scheduled
-    asynq ls dead
-    asynq ls enqueued:default
-    asynq ls inprogress
-
-### Enqueue
-
-There are two commands to enqueue tasks.
-
-Command `enq` takes a task ID and moves the task to **Enqueued** state. You can obtain the task ID by running `ls` command.
-
-Example:
-
-    asynq enq d:1575732274:bnogo8gt6toe23vhef0g
-
-Command `enqall` moves all tasks to **Enqueued** state from the specified state.
-
-Example:
-
-    asynq enqall retry
-
-Running the above command will move all **Retry** tasks to **Enqueued** state.
-
-### Delete
-
-There are two commands for task deletion.
-
-Command `del` takes a task ID and deletes the task. You can obtain the task ID by running `ls` command.
-
-Example:
-
-    asynq del r:1575732274:bnogo8gt6toe23vhef0g
-
-Command `delall` deletes all tasks which are in the specified state.
-
-Example:
-
-    asynq delall retry
-
-Running the above command will delete all **Retry** tasks.
-
-### Kill
-
-There are two commands to kill (i.e. move to dead state) tasks.
-
-Command `kill` takes a task ID and kills the task. You can obtain the task ID by running `ls` command.
-
-Example:
-
-    asynq kill r:1575732274:bnogo8gt6toe23vhef0g
-
-Command `killall` kills all tasks which are in the specified state.
-
-Example:
-
-    asynq killall retry
-
-Running the above command will move all **Retry** tasks to **Dead** state.
-
-### Cancel
-
-Command `cancel` takes a task ID and sends a cancelation signal to the goroutine processing the specified task.  
-You can obtain the task ID by running `ls` command.
-
-The task should be in "in-progress" state.
-Handler implementation needs to be context aware in order to actually stop processing.
-
-Example:
-
-    asynq cancel bnogo8gt6toe23vhef0g
-
-### Pause
-
-Command `pause` pauses the spcified queue. Tasks in paused queues are not processed by servers.
-To resume processing from the queue, use `unpause` command.
-To see which queues are currently paused, use `stats` command.
-
-Example:
-
-    asynq pause email
-    asynq unpause email
+      --cluster                connect to redis cluster
+      --cluster_addrs string   list of comma-separated redis server addresses
+```

 ## Config File

 You can use a config file to set default values for the flags.
-This is useful, for example when you have to connect to a remote redis server.

 By default, `asynq` will try to read config file located in
-`$HOME/.asynq.(yaml|json)`. You can specify the file location via `--config` flag.
+`$HOME/.asynq.(yml|json)`. You can specify the file location via `--config` flag.

 Config file example:

--- a/tools/asynq/cmd/cancel.go
+++ b/tools/asynq/cmd/cancel.go
@@ -1,53 +0,0 @@
-// Copyright 2020 Kentaro Hibino. All rights reserved.
-// Use of this source code is governed by a MIT license
-// that can be found in the LICENSE file.
-
-package cmd
-
-import (
-	"fmt"
-	"os"
-
-	"github.com/go-redis/redis/v7"
-	"github.com/hibiken/asynq/internal/rdb"
-	"github.com/spf13/cobra"
-	"github.com/spf13/viper"
-)
-
-// cancelCmd represents the cancel command
-var cancelCmd = &cobra.Command{
-	Use:   "cancel [task id]",
-	Short: "Sends a cancelation signal to the goroutine processing the specified task",
-	Long: `Cancel (asynq cancel) will send a cancelation signal to the goroutine processing 
-the specified task. 
-
-The command takes one argument which specifies the task to cancel.
-The task should be in in-progress state.
-Identifier for a task should be obtained by running "asynq ls" command.
-
-Handler implementation needs to be context aware for cancelation signal to
-actually cancel the processing.
-
-Example: asynq cancel bnogo8gt6toe23vhef0g`,
-	Args: cobra.ExactArgs(1),
-	Run:  cancel,
-}
-
-func init() {
-	rootCmd.AddCommand(cancelCmd)
-}
-
-func cancel(cmd *cobra.Command, args []string) {
-	r := rdb.NewRDB(redis.NewClient(&redis.Options{
-		Addr:     viper.GetString("uri"),
-		DB:       viper.GetInt("db"),
-		Password: viper.GetString("password"),
-	}))
-
-	err := r.PublishCancelation(args[0])
-	if err != nil {
-		fmt.Printf("could not send cancelation signal: %v\n", err)
-		os.Exit(1)
-	}
-	fmt.Printf("Successfully sent cancelation siganl for task %s\n", args[0])
-}
--- a/tools/asynq/cmd/cron.go
+++ b/tools/asynq/cmd/cron.go
@@ -0,0 +1,129 @@
+// Copyright 2020 Kentaro Hibino. All rights reserved.
+// Use of this source code is governed by a MIT license
+// that can be found in the LICENSE file.
+
+package cmd
+
+import (
+	"fmt"
+	"io"
+	"os"
+	"sort"
+	"time"
+
+	"github.com/hibiken/asynq"
+	"github.com/spf13/cobra"
+)
+
+func init() {
+	rootCmd.AddCommand(cronCmd)
+	cronCmd.AddCommand(cronListCmd)
+	cronCmd.AddCommand(cronHistoryCmd)
+	cronHistoryCmd.Flags().Int("page", 1, "page number")
+	cronHistoryCmd.Flags().Int("size", 30, "page size")
+}
+
+var cronCmd = &cobra.Command{
+	Use:   "cron",
+	Short: "Manage cron",
+}
+
+var cronListCmd = &cobra.Command{
+	Use:   "ls",
+	Short: "List cron entries",
+	Run:   cronList,
+}
+
+var cronHistoryCmd = &cobra.Command{
+	Use:   "history [ENTRY_ID...]",
+	Short: "Show history of each cron tasks",
+	Args:  cobra.MinimumNArgs(1),
+	Run:   cronHistory,
+}
+
+func cronList(cmd *cobra.Command, args []string) {
+	inspector := createInspector()
+
+	entries, err := inspector.SchedulerEntries()
+	if err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+	if len(entries) == 0 {
+		fmt.Println("No scheduler entries")
+		return
+	}
+
+	// Sort entries by spec.
+	sort.Slice(entries, func(i, j int) bool {
+		x, y := entries[i], entries[j]
+		return x.Spec < y.Spec
+	})
+
+	cols := []string{"EntryID", "Spec", "Type", "Payload", "Options", "Next", "Prev"}
+	printRows := func(w io.Writer, tmpl string) {
+		for _, e := range entries {
+			fmt.Fprintf(w, tmpl, e.ID, e.Spec, e.Task.Type, e.Task.Payload, e.Opts,
+				nextEnqueue(e.Next), prevEnqueue(e.Prev))
+		}
+	}
+	printTable(cols, printRows)
+}
+
+// Returns a string describing when the next enqueue will happen.
+func nextEnqueue(nextEnqueueAt time.Time) string {
+	d := nextEnqueueAt.Sub(time.Now()).Round(time.Second)
+	if d < 0 {
+		return "Now"
+	}
+	return fmt.Sprintf("In %v", d)
+}
+
+// Returns a string describing when the previous enqueue was.
+func prevEnqueue(prevEnqueuedAt time.Time) string {
+	if prevEnqueuedAt.IsZero() {
+		return "N/A"
+	}
+	return fmt.Sprintf("%v ago", time.Since(prevEnqueuedAt).Round(time.Second))
+}
+
+func cronHistory(cmd *cobra.Command, args []string) {
+	pageNum, err := cmd.Flags().GetInt("page")
+	if err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+	pageSize, err := cmd.Flags().GetInt("size")
+	if err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+	inspector := createInspector()
+	for i, entryID := range args {
+		if i > 0 {
+			fmt.Printf("\n%s\n", separator)
+		}
+		fmt.Println()
+
+		fmt.Printf("Entry: %s\n\n", entryID)
+
+		events, err := inspector.ListSchedulerEnqueueEvents(
+			entryID, asynq.PageSize(pageSize), asynq.Page(pageNum))
+		if err != nil {
+			fmt.Printf("error: %v\n", err)
+			continue
+		}
+		if len(events) == 0 {
+			fmt.Printf("No scheduler enqueue events found for entry: %s\n", entryID)
+			continue
+		}
+
+		cols := []string{"TaskID", "EnqueuedAt"}
+		printRows := func(w io.Writer, tmpl string) {
+			for _, e := range events {
+				fmt.Fprintf(w, tmpl, e.TaskID, e.EnqueuedAt)
+			}
+		}
+		printTable(cols, printRows)
+	}
+}
--- a/tools/asynq/cmd/del.go
+++ b/tools/asynq/cmd/del.go
@@ -1,73 +0,0 @@
-// Copyright 2020 Kentaro Hibino. All rights reserved.
-// Use of this source code is governed by a MIT license
-// that can be found in the LICENSE file.
-
-package cmd
-
-import (
-	"fmt"
-	"os"
-
-	"github.com/go-redis/redis/v7"
-	"github.com/hibiken/asynq/internal/rdb"
-	"github.com/spf13/cobra"
-	"github.com/spf13/viper"
-)
-
-// delCmd represents the del command
-var delCmd = &cobra.Command{
-	Use:   "del [task id]",
-	Short: "Deletes a task given an identifier",
-	Long: `Del (asynq del) will delete a task given an identifier.
-
-The command takes one argument which specifies the task to delete.
-The task should be in either scheduled, retry or dead state.
-Identifier for a task should be obtained by running "asynq ls" command.
-
-Example: asynq enq d:1575732274:bnogo8gt6toe23vhef0g`,
-	Args: cobra.ExactArgs(1),
-	Run:  del,
-}
-
-func init() {
-	rootCmd.AddCommand(delCmd)
-
-	// Here you will define your flags and configuration settings.
-
-	// Cobra supports Persistent Flags which will work for this command
-	// and all subcommands, e.g.:
-	// delCmd.PersistentFlags().String("foo", "", "A help for foo")
-
-	// Cobra supports local flags which will only run when this command
-	// is called directly, e.g.:
-	// delCmd.Flags().BoolP("toggle", "t", false, "Help message for toggle")
-}
-
-func del(cmd *cobra.Command, args []string) {
-	id, score, qtype, err := parseQueryID(args[0])
-	if err != nil {
-		fmt.Println(err)
-		os.Exit(1)
-	}
-	r := rdb.NewRDB(redis.NewClient(&redis.Options{
-		Addr:     viper.GetString("uri"),
-		DB:       viper.GetInt("db"),
-		Password: viper.GetString("password"),
-	}))
-	switch qtype {
-	case "s":
-		err = r.DeleteScheduledTask(id, score)
-	case "r":
-		err = r.DeleteRetryTask(id, score)
-	case "d":
-		err = r.DeleteDeadTask(id, score)
-	default:
-		fmt.Println("invalid argument")
-		os.Exit(1)
-	}
-	if err != nil {
-		fmt.Println(err)
-		os.Exit(1)
-	}
-	fmt.Printf("Successfully deleted %v\n", args[0])
-}
--- a/tools/asynq/cmd/delall.go
+++ b/tools/asynq/cmd/delall.go
@@ -1,71 +0,0 @@
-// Copyright 2020 Kentaro Hibino. All rights reserved.
-// Use of this source code is governed by a MIT license
-// that can be found in the LICENSE file.
-
-package cmd
-
-import (
-	"fmt"
-	"os"
-
-	"github.com/go-redis/redis/v7"
-	"github.com/hibiken/asynq/internal/rdb"
-	"github.com/spf13/cobra"
-	"github.com/spf13/viper"
-)
-
-var delallValidArgs = []string{"scheduled", "retry", "dead"}
-
-// delallCmd represents the delall command
-var delallCmd = &cobra.Command{
-	Use:   "delall [state]",
-	Short: "Deletes all tasks in the specified state",
-	Long: `Delall (asynq delall) will delete all tasks in the specified state.
-
-The argument should be one of "scheduled", "retry", or "dead".
-
-Example: asynq delall dead -> Deletes all dead tasks`,
-	ValidArgs: delallValidArgs,
-	Args:      cobra.ExactValidArgs(1),
-	Run:       delall,
-}
-
-func init() {
-	rootCmd.AddCommand(delallCmd)
-
-	// Here you will define your flags and configuration settings.
-
-	// Cobra supports Persistent Flags which will work for this command
-	// and all subcommands, e.g.:
-	// delallCmd.PersistentFlags().String("foo", "", "A help for foo")
-
-	// Cobra supports local flags which will only run when this command
-	// is called directly, e.g.:
-	// delallCmd.Flags().BoolP("toggle", "t", false, "Help message for toggle")
-}
-
-func delall(cmd *cobra.Command, args []string) {
-	c := redis.NewClient(&redis.Options{
-		Addr:     viper.GetString("uri"),
-		DB:       viper.GetInt("db"),
-		Password: viper.GetString("password"),
-	})
-	r := rdb.NewRDB(c)
-	var err error
-	switch args[0] {
-	case "scheduled":
-		err = r.DeleteAllScheduledTasks()
-	case "retry":
-		err = r.DeleteAllRetryTasks()
-	case "dead":
-		err = r.DeleteAllDeadTasks()
-	default:
-		fmt.Printf("error: `asynq delall [state]` only accepts %v as the argument.\n", delallValidArgs)
-		os.Exit(1)
-	}
-	if err != nil {
-		fmt.Println(err)
-		os.Exit(1)
-	}
-	fmt.Printf("Deleted all tasks in %q state\n", args[0])
-}
--- a/tools/asynq/cmd/enq.go
+++ b/tools/asynq/cmd/enq.go
@@ -1,76 +0,0 @@
-// Copyright 2020 Kentaro Hibino. All rights reserved.
-// Use of this source code is governed by a MIT license
-// that can be found in the LICENSE file.
-
-package cmd
-
-import (
-	"fmt"
-	"os"
-
-	"github.com/go-redis/redis/v7"
-	"github.com/hibiken/asynq/internal/rdb"
-	"github.com/spf13/cobra"
-	"github.com/spf13/viper"
-)
-
-// enqCmd represents the enq command
-var enqCmd = &cobra.Command{
-	Use:   "enq [task id]",
-	Short: "Enqueues a task given an identifier",
-	Long: `Enq (asynq enq) will enqueue a task given an identifier.
-
-The command takes one argument which specifies the task to enqueue.
-The task should be in either scheduled, retry or dead state.
-Identifier for a task should be obtained by running "asynq ls" command.
-
-The task enqueued by this command will be processed as soon as the task 
-gets dequeued by a processor.
-
-Example: asynq enq d:1575732274:bnogo8gt6toe23vhef0g`,
-	Args: cobra.ExactArgs(1),
-	Run:  enq,
-}
-
-func init() {
-	rootCmd.AddCommand(enqCmd)
-
-	// Here you will define your flags and configuration settings.
-
-	// Cobra supports Persistent Flags which will work for this command
-	// and all subcommands, e.g.:
-	// enqCmd.PersistentFlags().String("foo", "", "A help for foo")
-
-	// Cobra supports local flags which will only run when this command
-	// is called directly, e.g.:
-	// enqCmd.Flags().BoolP("toggle", "t", false, "Help message for toggle")
-}
-
-func enq(cmd *cobra.Command, args []string) {
-	id, score, qtype, err := parseQueryID(args[0])
-	if err != nil {
-		fmt.Println(err)
-		os.Exit(1)
-	}
-	r := rdb.NewRDB(redis.NewClient(&redis.Options{
-		Addr:     viper.GetString("uri"),
-		DB:       viper.GetInt("db"),
-		Password: viper.GetString("password"),
-	}))
-	switch qtype {
-	case "s":
-		err = r.EnqueueScheduledTask(id, score)
-	case "r":
-		err = r.EnqueueRetryTask(id, score)
-	case "d":
-		err = r.EnqueueDeadTask(id, score)
-	default:
-		fmt.Println("invalid argument")
-		os.Exit(1)
-	}
-	if err != nil {
-		fmt.Println(err)
-		os.Exit(1)
-	}
-	fmt.Printf("Successfully enqueued %v\n", args[0])
-}
--- a/tools/asynq/cmd/enqall.go
+++ b/tools/asynq/cmd/enqall.go
@@ -1,75 +0,0 @@
-// Copyright 2020 Kentaro Hibino. All rights reserved.
-// Use of this source code is governed by a MIT license
-// that can be found in the LICENSE file.
-
-package cmd
-
-import (
-	"fmt"
-	"os"
-
-	"github.com/go-redis/redis/v7"
-	"github.com/hibiken/asynq/internal/rdb"
-	"github.com/spf13/cobra"
-	"github.com/spf13/viper"
-)
-
-var enqallValidArgs = []string{"scheduled", "retry", "dead"}
-
-// enqallCmd represents the enqall command
-var enqallCmd = &cobra.Command{
-	Use:   "enqall [state]",
-	Short: "Enqueues all tasks in the specified state",
-	Long: `Enqall (asynq enqall) will enqueue all tasks in the specified state.
-
-The argument should be one of "scheduled", "retry", or "dead".
-
-The tasks enqueued by this command will be processed as soon as it
-gets dequeued by a processor.
-
-Example: asynq enqall dead -> Enqueues all dead tasks`,
-	ValidArgs: enqallValidArgs,
-	Args:      cobra.ExactValidArgs(1),
-	Run:       enqall,
-}
-
-func init() {
-	rootCmd.AddCommand(enqallCmd)
-
-	// Here you will define your flags and configuration settings.
-
-	// Cobra supports Persistent Flags which will work for this command
-	// and all subcommands, e.g.:
-	// enqallCmd.PersistentFlags().String("foo", "", "A help for foo")
-
-	// Cobra supports local flags which will only run when this command
-	// is called directly, e.g.:
-	// enqallCmd.Flags().BoolP("toggle", "t", false, "Help message for toggle")
-}
-
-func enqall(cmd *cobra.Command, args []string) {
-	c := redis.NewClient(&redis.Options{
-		Addr:     viper.GetString("uri"),
-		DB:       viper.GetInt("db"),
-		Password: viper.GetString("password"),
-	})
-	r := rdb.NewRDB(c)
-	var n int64
-	var err error
-	switch args[0] {
-	case "scheduled":
-		n, err = r.EnqueueAllScheduledTasks()
-	case "retry":
-		n, err = r.EnqueueAllRetryTasks()
-	case "dead":
-		n, err = r.EnqueueAllDeadTasks()
-	default:
-		fmt.Printf("error: `asynq enqall [state]` only accepts %v as the argument.\n", enqallValidArgs)
-		os.Exit(1)
-	}
-	if err != nil {
-		fmt.Println(err)
-		os.Exit(1)
-	}
-	fmt.Printf("Enqueued %d tasks in %q state\n", n, args[0])
-}
--- a/tools/asynq/cmd/history.go
+++ b/tools/asynq/cmd/history.go
@@ -1,71 +0,0 @@
-// Copyright 2020 Kentaro Hibino. All rights reserved.
-// Use of this source code is governed by a MIT license
-// that can be found in the LICENSE file.
-
-package cmd
-
-import (
-	"fmt"
-	"os"
-	"strings"
-	"text/tabwriter"
-
-	"github.com/go-redis/redis/v7"
-	"github.com/hibiken/asynq/internal/rdb"
-	"github.com/spf13/cobra"
-	"github.com/spf13/viper"
-)
-
-var days int
-
-// historyCmd represents the history command
-var historyCmd = &cobra.Command{
-	Use:   "history",
-	Short: "Shows historical aggregate data",
-	Long: `History (asynq history) will show the number of processed and failed tasks
-from the last x days.
-
-By default, it will show the data from the last 10 days.
-
-Example: asynq history -x=30 -> Shows stats from the last 30 days`,
-	Args: cobra.NoArgs,
-	Run:  history,
-}
-
-func init() {
-	rootCmd.AddCommand(historyCmd)
-	historyCmd.Flags().IntVarP(&days, "days", "x", 10, "show data from last x days")
-}
-
-func history(cmd *cobra.Command, args []string) {
-	c := redis.NewClient(&redis.Options{
-		Addr:     viper.GetString("uri"),
-		DB:       viper.GetInt("db"),
-		Password: viper.GetString("password"),
-	})
-	r := rdb.NewRDB(c)
-
-	stats, err := r.HistoricalStats(days)
-	if err != nil {
-		fmt.Println(err)
-		os.Exit(1)
-	}
-	printDailyStats(stats)
-}
-
-func printDailyStats(stats []*rdb.DailyStats) {
-	format := strings.Repeat("%v\t", 4) + "\n"
-	tw := new(tabwriter.Writer).Init(os.Stdout, 0, 8, 2, ' ', 0)
-	fmt.Fprintf(tw, format, "Date (UTC)", "Processed", "Failed", "Error Rate")
-	fmt.Fprintf(tw, format, "----------", "---------", "------", "----------")
-	for _, s := range stats {
-		var errrate string
-		if s.Processed == 0 {
-			errrate = "N/A"
-		} else {
-			errrate = fmt.Sprintf("%.2f%%", float64(s.Failed)/float64(s.Processed)*100)
-		}
-		fmt.Fprintf(tw, format, s.Time.Format("2006-01-02"), s.Processed, s.Failed, errrate)
-	}
-	tw.Flush()
-}
--- a/tools/asynq/cmd/kill.go
+++ b/tools/asynq/cmd/kill.go
@@ -1,72 +0,0 @@
-// Copyright 2020 Kentaro Hibino. All rights reserved.
-// Use of this source code is governed by a MIT license
-// that can be found in the LICENSE file.
-
-package cmd
-
-import (
-	"fmt"
-	"os"
-
-	"github.com/go-redis/redis/v7"
-	"github.com/hibiken/asynq/internal/rdb"
-	"github.com/spf13/cobra"
-	"github.com/spf13/viper"
-)
-
-// killCmd represents the kill command
-var killCmd = &cobra.Command{
-	Use:   "kill [task id]",
-	Short: "Kills a task given an identifier",
-	Long: `Kill (asynq kill) will put a task in dead state given an identifier.
-
-The command takes one argument which specifies the task to kill.
-The task should be in either scheduled or retry state.
-Identifier for a task should be obtained by running "asynq ls" command.
-
-Example: asynq kill r:1575732274:bnogo8gt6toe23vhef0g`,
-	Args: cobra.ExactArgs(1),
-	Run:  kill,
-}
-
-func init() {
-	rootCmd.AddCommand(killCmd)
-
-	// Here you will define your flags and configuration settings.
-
-	// Cobra supports Persistent Flags which will work for this command
-	// and all subcommands, e.g.:
-	// killCmd.PersistentFlags().String("foo", "", "A help for foo")
-
-	// Cobra supports local flags which will only run when this command
-	// is called directly, e.g.:
-	// killCmd.Flags().BoolP("toggle", "t", false, "Help message for toggle")
-}
-
-func kill(cmd *cobra.Command, args []string) {
-	id, score, qtype, err := parseQueryID(args[0])
-	if err != nil {
-		fmt.Println(err)
-		os.Exit(1)
-	}
-	r := rdb.NewRDB(redis.NewClient(&redis.Options{
-		Addr:     viper.GetString("uri"),
-		DB:       viper.GetInt("db"),
-		Password: viper.GetString("password"),
-	}))
-	switch qtype {
-	case "s":
-		err = r.KillScheduledTask(id, score)
-	case "r":
-		err = r.KillRetryTask(id, score)
-	default:
-		fmt.Println("invalid argument")
-		os.Exit(1)
-	}
-	if err != nil {
-		fmt.Println(err)
-		os.Exit(1)
-	}
-	fmt.Printf("Successfully killed %v\n", args[0])
-
-}
--- a/tools/asynq/cmd/killall.go
+++ b/tools/asynq/cmd/killall.go
@@ -1,70 +0,0 @@
-// Copyright 2020 Kentaro Hibino. All rights reserved.
-// Use of this source code is governed by a MIT license
-// that can be found in the LICENSE file.
-
-package cmd
-
-import (
-	"fmt"
-	"os"
-
-	"github.com/go-redis/redis/v7"
-	"github.com/hibiken/asynq/internal/rdb"
-	"github.com/spf13/cobra"
-	"github.com/spf13/viper"
-)
-
-var killallValidArgs = []string{"scheduled", "retry"}
-
-// killallCmd represents the killall command
-var killallCmd = &cobra.Command{
-	Use:   "killall [state]",
-	Short: "Kills all tasks in the specified state",
-	Long: `Killall (asynq killall) will update all tasks from the specified state to dead state.
-
-The argument should be either "scheduled" or "retry".
-
-Example: asynq killall retry -> Update all retry tasks to dead tasks`,
-	ValidArgs: killallValidArgs,
-	Args:      cobra.ExactValidArgs(1),
-	Run:       killall,
-}
-
-func init() {
-	rootCmd.AddCommand(killallCmd)
-
-	// Here you will define your flags and configuration settings.
-
-	// Cobra supports Persistent Flags which will work for this command
-	// and all subcommands, e.g.:
-	// killallCmd.PersistentFlags().String("foo", "", "A help for foo")
-
-	// Cobra supports local flags which will only run when this command
-	// is called directly, e.g.:
-	// killallCmd.Flags().BoolP("toggle", "t", false, "Help message for toggle")
-}
-
-func killall(cmd *cobra.Command, args []string) {
-	c := redis.NewClient(&redis.Options{
-		Addr:     viper.GetString("uri"),
-		DB:       viper.GetInt("db"),
-		Password: viper.GetString("password"),
-	})
-	r := rdb.NewRDB(c)
-	var n int64
-	var err error
-	switch args[0] {
-	case "scheduled":
-		n, err = r.KillAllScheduledTasks()
-	case "retry":
-		n, err = r.KillAllRetryTasks()
-	default:
-		fmt.Printf("error: `asynq killall [state]` only accepts %v as the argument.\n", killallValidArgs)
-		os.Exit(1)
-	}
-	if err != nil {
-		fmt.Println(err)
-		os.Exit(1)
-	}
-	fmt.Printf("Successfully updated %d tasks to \"dead\" state\n", n)
-}
--- a/tools/asynq/cmd/ls.go
+++ b/tools/asynq/cmd/ls.go
@@ -1,229 +0,0 @@
-// Copyright 2020 Kentaro Hibino. All rights reserved.
-// Use of this source code is governed by a MIT license
-// that can be found in the LICENSE file.
-
-package cmd
-
-import (
-	"fmt"
-	"io"
-	"os"
-	"strconv"
-	"strings"
-	"time"
-
-	"github.com/go-redis/redis/v7"
-	"github.com/google/uuid"
-	"github.com/hibiken/asynq/internal/rdb"
-	"github.com/spf13/cobra"
-	"github.com/spf13/viper"
-)
-
-var lsValidArgs = []string{"enqueued", "inprogress", "scheduled", "retry", "dead"}
-
-// lsCmd represents the ls command
-var lsCmd = &cobra.Command{
-	Use:   "ls [state]",
-	Short: "Lists tasks in the specified state",
-	Long: `Ls (asynq ls) will list all tasks in the specified state in a table format.
-
-The command takes one argument which specifies the state of tasks.
-The argument value should be one of "enqueued", "inprogress", "scheduled",
-"retry", or "dead".
-
-Example:
-asynq ls dead -> Lists all tasks in dead state
-
-Enqueued tasks requires a queue name after ":"
-Example:
-asynq ls enqueued:default  -> List tasks from default queue
-asynq ls enqueued:critical -> List tasks from critical queue 
-`,
-	Args: cobra.ExactValidArgs(1),
-	Run:  ls,
-}
-
-// Flags
-var pageSize int
-var pageNum int
-
-func init() {
-	rootCmd.AddCommand(lsCmd)
-	lsCmd.Flags().IntVar(&pageSize, "size", 30, "page size")
-	lsCmd.Flags().IntVar(&pageNum, "page", 0, "page number - zero indexed (default 0)")
-}
-
-func ls(cmd *cobra.Command, args []string) {
-	if pageSize < 0 {
-		fmt.Println("page size cannot be negative.")
-		os.Exit(1)
-	}
-	if pageNum < 0 {
-		fmt.Println("page number cannot be negative.")
-		os.Exit(1)
-	}
-	c := redis.NewClient(&redis.Options{
-		Addr:     viper.GetString("uri"),
-		DB:       viper.GetInt("db"),
-		Password: viper.GetString("password"),
-	})
-	r := rdb.NewRDB(c)
-	parts := strings.Split(args[0], ":")
-	switch parts[0] {
-	case "enqueued":
-		if len(parts) != 2 {
-			fmt.Printf("error: Missing queue name\n`asynq ls enqueued:[queue name]`\n")
-			os.Exit(1)
-		}
-		listEnqueued(r, parts[1])
-	case "inprogress":
-		listInProgress(r)
-	case "scheduled":
-		listScheduled(r)
-	case "retry":
-		listRetry(r)
-	case "dead":
-		listDead(r)
-	default:
-		fmt.Printf("error: `asynq ls [state]`\nonly accepts %v as the argument.\n", lsValidArgs)
-		os.Exit(1)
-	}
-}
-
-// queryID returns an identifier used for "enq" command.
-// score is the zset score and queryType should be one
-// of "s", "r" or "d" (scheduled, retry, dead respectively).
-func queryID(id uuid.UUID, score int64, qtype string) string {
-	const format = "%v:%v:%v"
-	return fmt.Sprintf(format, qtype, score, id)
-}
-
-// parseQueryID is a reverse operation of queryID function.
-// It takes a queryID and return each part of id with proper
-// type if valid, otherwise it reports an error.
-func parseQueryID(queryID string) (id uuid.UUID, score int64, qtype string, err error) {
-	parts := strings.Split(queryID, ":")
-	if len(parts) != 3 {
-		return uuid.Nil, 0, "", fmt.Errorf("invalid id")
-	}
-	id, err = uuid.Parse(parts[2])
-	if err != nil {
-		return uuid.Nil, 0, "", fmt.Errorf("invalid id")
-	}
-	score, err = strconv.ParseInt(parts[1], 10, 64)
-	if err != nil {
-		return uuid.Nil, 0, "", fmt.Errorf("invalid id")
-	}
-	qtype = parts[0]
-	if len(qtype) != 1 || !strings.Contains("srd", qtype) {
-		return uuid.Nil, 0, "", fmt.Errorf("invalid id")
-	}
-	return id, score, qtype, nil
-}
-
-func listEnqueued(r *rdb.RDB, qname string) {
-	tasks, err := r.ListEnqueued(qname, rdb.Pagination{Size: pageSize, Page: pageNum})
-	if err != nil {
-		fmt.Println(err)
-		os.Exit(1)
-	}
-	if len(tasks) == 0 {
-		fmt.Printf("No enqueued tasks in %q queue\n", qname)
-		return
-	}
-	cols := []string{"ID", "Type", "Payload", "Queue"}
-	printRows := func(w io.Writer, tmpl string) {
-		for _, t := range tasks {
-			fmt.Fprintf(w, tmpl, t.ID, t.Type, t.Payload, t.Queue)
-		}
-	}
-	printTable(cols, printRows)
-	fmt.Printf("\nShowing %d tasks from page %d\n", len(tasks), pageNum)
-}
-
-func listInProgress(r *rdb.RDB) {
-	tasks, err := r.ListInProgress(rdb.Pagination{Size: pageSize, Page: pageNum})
-	if err != nil {
-		fmt.Println(err)
-		os.Exit(1)
-	}
-	if len(tasks) == 0 {
-		fmt.Println("No in-progress tasks")
-		return
-	}
-	cols := []string{"ID", "Type", "Payload"}
-	printRows := func(w io.Writer, tmpl string) {
-		for _, t := range tasks {
-			fmt.Fprintf(w, tmpl, t.ID, t.Type, t.Payload)
-		}
-	}
-	printTable(cols, printRows)
-	fmt.Printf("\nShowing %d tasks from page %d\n", len(tasks), pageNum)
-}
-
-func listScheduled(r *rdb.RDB) {
-	tasks, err := r.ListScheduled(rdb.Pagination{Size: pageSize, Page: pageNum})
-	if err != nil {
-		fmt.Println(err)
-		os.Exit(1)
-	}
-	if len(tasks) == 0 {
-		fmt.Println("No scheduled tasks")
-		return
-	}
-	cols := []string{"ID", "Type", "Payload", "Process In", "Queue"}
-	printRows := func(w io.Writer, tmpl string) {
-		for _, t := range tasks {
-			processIn := fmt.Sprintf("%.0f seconds", t.ProcessAt.Sub(time.Now()).Seconds())
-			fmt.Fprintf(w, tmpl, queryID(t.ID, t.Score, "s"), t.Type, t.Payload, processIn, t.Queue)
-		}
-	}
-	printTable(cols, printRows)
-	fmt.Printf("\nShowing %d tasks from page %d\n", len(tasks), pageNum)
-}
-
-func listRetry(r *rdb.RDB) {
-	tasks, err := r.ListRetry(rdb.Pagination{Size: pageSize, Page: pageNum})
-	if err != nil {
-		fmt.Println(err)
-		os.Exit(1)
-	}
-	if len(tasks) == 0 {
-		fmt.Println("No retry tasks")
-		return
-	}
-	cols := []string{"ID", "Type", "Payload", "Next Retry", "Last Error", "Retried", "Max Retry", "Queue"}
-	printRows := func(w io.Writer, tmpl string) {
-		for _, t := range tasks {
-			var nextRetry string
-			if d := t.ProcessAt.Sub(time.Now()); d > 0 {
-				nextRetry = fmt.Sprintf("in %v", d.Round(time.Second))
-			} else {
-				nextRetry = "right now"
-			}
-			fmt.Fprintf(w, tmpl, queryID(t.ID, t.Score, "r"), t.Type, t.Payload, nextRetry, t.ErrorMsg, t.Retried, t.Retry, t.Queue)
-		}
-	}
-	printTable(cols, printRows)
-	fmt.Printf("\nShowing %d tasks from page %d\n", len(tasks), pageNum)
-}
-
-func listDead(r *rdb.RDB) {
-	tasks, err := r.ListDead(rdb.Pagination{Size: pageSize, Page: pageNum})
-	if err != nil {
-		fmt.Println(err)
-		os.Exit(1)
-	}
-	if len(tasks) == 0 {
-		fmt.Println("No dead tasks")
-		return
-	}
-	cols := []string{"ID", "Type", "Payload", "Last Failed", "Last Error", "Queue"}
-	printRows := func(w io.Writer, tmpl string) {
-		for _, t := range tasks {
-			fmt.Fprintf(w, tmpl, queryID(t.ID, t.Score, "d"), t.Type, t.Payload, t.LastFailedAt, t.ErrorMsg, t.Queue)
-		}
-	}
-	printTable(cols, printRows)
-	fmt.Printf("\nShowing %d tasks from page %d\n", len(tasks), pageNum)
-}
--- a/tools/asynq/cmd/migrate.go
+++ b/tools/asynq/cmd/migrate.go
@@ -19,11 +19,10 @@ import (
 	"github.com/spf13/viper"
 )

-// migrateCmd represents the migrate command
 var migrateCmd = &cobra.Command{
 	Use:   "migrate",
-	Short: fmt.Sprintf("Migrate all tasks to be compatible with asynq@%s", base.Version),
-	Long:  fmt.Sprintf("Migrate (asynq migrate) will convert all tasks in redis to be compatible with asynq@%s.", base.Version),
+	Short: fmt.Sprintf("Migrate all tasks to be compatible with asynq v%s", base.Version),
+	Args:  cobra.NoArgs,
 	Run:   migrate,
 }

@@ -37,28 +36,206 @@ func migrate(cmd *cobra.Command, args []string) {
 		DB:       viper.GetInt("db"),
 		Password: viper.GetString("password"),
 	})
+	r := createRDB()

-	lists := []string{base.InProgressQueue}
+	/*** Migrate from 0.9 to 0.10, 0.11 compatible ***/
+	lists := []string{"asynq:in_progress"}
 	allQueues, err := c.SMembers(base.AllQueues).Result()
 	if err != nil {
-		fmt.Printf("error: could not read all queues: %v", err)
+		printError(fmt.Errorf("could not read all queues: %v", err))
 		os.Exit(1)
 	}
 	lists = append(lists, allQueues...)
 	for _, key := range lists {
 		if err := migrateList(c, key); err != nil {
-			fmt.Printf("error: %v", err)
+			printError(err)
 			os.Exit(1)
 		}
 	}

-	zsets := []string{base.ScheduledQueue, base.RetryQueue, base.DeadQueue}
+	zsets := []string{"asynq:scheduled", "asynq:retry", "asynq:dead"}
 	for _, key := range zsets {
 		if err := migrateZSet(c, key); err != nil {
-			fmt.Printf("error: %v", err)
+			printError(err)
 			os.Exit(1)
 		}
 	}
+
+	/*** Migrate from 0.11 to 0.12 compatible ***/
+	if err := createBackup(c, base.AllQueues); err != nil {
+		printError(err)
+		os.Exit(1)
+	}
+	for _, qkey := range allQueues {
+		qname := strings.TrimPrefix(qkey, "asynq:queues:")
+		if err := c.SAdd(base.AllQueues, qname).Err(); err != nil {
+			err = fmt.Errorf("could not add queue name %q to %q set: %v\n",
+				qname, base.AllQueues, err)
+			printError(err)
+			os.Exit(1)
+		}
+	}
+	if err := deleteBackup(c, base.AllQueues); err != nil {
+		printError(err)
+		os.Exit(1)
+	}
+
+	for _, qkey := range allQueues {
+		qname := strings.TrimPrefix(qkey, "asynq:queues:")
+		if exists := c.Exists(qkey).Val(); exists == 1 {
+			if err := c.Rename(qkey, base.QueueKey(qname)).Err(); err != nil {
+				printError(fmt.Errorf("could not rename key %q: %v\n", qkey, err))
+				os.Exit(1)
+			}
+		}
+	}
+
+	if err := partitionZSetMembersByQueue(c, "asynq:scheduled", base.ScheduledKey); err != nil {
+		printError(err)
+		os.Exit(1)
+	}
+	if err := partitionZSetMembersByQueue(c, "asynq:retry", base.RetryKey); err != nil {
+		printError(err)
+		os.Exit(1)
+	}
+	// Note: base.DeadKey function was renamed in v0.14. We define the legacy function here since we need it for this migration script.
+	deadKeyFunc := func(qname string) string { return fmt.Sprintf("asynq:{%s}:dead", qname) } 
+	if err := partitionZSetMembersByQueue(c, "asynq:dead", deadKeyFunc); err != nil {
+		printError(err)
+		os.Exit(1)
+	}
+	if err := partitionZSetMembersByQueue(c, "asynq:deadlines", base.DeadlinesKey); err != nil {
+		printError(err)
+		os.Exit(1)
+	}
+	if err := partitionListMembersByQueue(c, "asynq:in_progress", base.ActiveKey); err != nil {
+		printError(err)
+		os.Exit(1)
+	}
+
+	paused, err := c.SMembers("asynq:paused").Result()
+	if err != nil {
+		printError(fmt.Errorf("command SMEMBERS asynq:paused failed: %v", err))
+		os.Exit(1)
+	}
+	for _, qkey := range paused {
+		qname := strings.TrimPrefix(qkey, "asynq:queues:")
+		if err := r.Pause(qname); err != nil {
+			printError(err)
+			os.Exit(1)
+		}
+	}
+	if err := deleteKey(c, "asynq:paused"); err != nil {
+		printError(err)
+		os.Exit(1)
+	}
+
+	if err := deleteKey(c, "asynq:servers"); err != nil {
+		printError(err)
+		os.Exit(1)
+	}
+	if err := deleteKey(c, "asynq:workers"); err != nil {
+		printError(err)
+		os.Exit(1)
+	}
+
+	/*** Migrate from 0.13 to 0.14 compatible ***/
+
+	// Move all dead tasks to archived ZSET.
+	for _, qname := range allQueues {
+		zs, err := c.ZRangeWithScores(deadKeyFunc(qname), 0, -1).Result()
+		if err != nil {
+			printError(err)
+			os.Exit(1)
+		}
+		for _, z := range zs {
+			if err := c.ZAdd(base.ArchivedKey(qname), &z).Err(); err != nil {
+				printError(err)
+				os.Exit(1)
+			}
+		}
+		if err := deleteKey(c, deadKeyFunc(qname)); err != nil {
+			printError(err)
+			os.Exit(1)
+		}
+	}
+}
+
+func backupKey(key string) string {
+	return fmt.Sprintf("%s:backup", key)
+}
+
+func createBackup(c *redis.Client, key string) error {
+	err := c.Rename(key, backupKey(key)).Err()
+	if err != nil {
+		return fmt.Errorf("could not rename key %q: %v", key, err)
+	}
+	return nil
+}
+
+func deleteBackup(c *redis.Client, key string) error {
+	return deleteKey(c, backupKey(key))
+}
+
+func deleteKey(c *redis.Client, key string) error {
+	exists := c.Exists(key).Val()
+	if exists == 0 {
+		// key does not exist
+		return nil
+	}
+	err := c.Del(key).Err()
+	if err != nil {
+		return fmt.Errorf("could not delete key %q: %v", key, err)
+	}
+	return nil
+}
+
+func printError(err error) {
+	fmt.Println(err)
+	fmt.Println()
+	fmt.Println("Migrate command error")
+	fmt.Println("Please file an issue on Github at https://github.com/hibiken/asynq/issues/new/choose")
+}
+
+func partitionZSetMembersByQueue(c *redis.Client, key string, newKeyFunc func(string) string) error {
+	zs, err := c.ZRangeWithScores(key, 0, -1).Result()
+	if err != nil {
+		return fmt.Errorf("command ZRANGE %s 0 -1 WITHSCORES failed: %v", key, err)
+	}
+	for _, z := range zs {
+		s := cast.ToString(z.Member)
+		msg, err := base.DecodeMessage(s)
+		if err != nil {
+			return fmt.Errorf("could not decode message from %q: %v", key, err)
+		}
+		if err := c.ZAdd(newKeyFunc(msg.Queue), &z).Err(); err != nil {
+			return fmt.Errorf("could not add %v to %q: %v", z, newKeyFunc(msg.Queue))
+		}
+	}
+	if err := deleteKey(c, key); err != nil {
+		return err
+	}
+	return nil
+}
+
+func partitionListMembersByQueue(c *redis.Client, key string, newKeyFunc func(string) string) error {
+	data, err := c.LRange(key, 0, -1).Result()
+	if err != nil {
+		return fmt.Errorf("command LRANGE %s 0 -1 failed: %v", key, err)
+	}
+	for _, s := range data {
+		msg, err := base.DecodeMessage(s)
+		if err != nil {
+			return fmt.Errorf("could not decode message from %q: %v", key, err)
+		}
+		if err := c.LPush(newKeyFunc(msg.Queue), s).Err(); err != nil {
+			return fmt.Errorf("could not add %v to %q: %v", s, newKeyFunc(msg.Queue))
+		}
+	}
+	if err := deleteKey(c, key); err != nil {
+		return err
+	}
+	return nil
 }

 type oldTaskMessage struct {
--- a/tools/asynq/cmd/pause.go
+++ b/tools/asynq/cmd/pause.go
@@ -1,47 +0,0 @@
-// Copyright 2020 Kentaro Hibino. All rights reserved.
-// Use of this source code is governed by a MIT license
-// that can be found in the LICENSE file.
-
-package cmd
-
-import (
-	"fmt"
-	"os"
-
-	"github.com/go-redis/redis/v7"
-	"github.com/hibiken/asynq/internal/rdb"
-	"github.com/spf13/cobra"
-	"github.com/spf13/viper"
-)
-
-// pauseCmd represents the pause command
-var pauseCmd = &cobra.Command{
-	Use:   "pause [queue name]",
-	Short: "Pauses the specified queue",
-	Long: `Pause (asynq pause) will pause the specified queue.
-Asynq servers will not process tasks from paused queues.
-Use the "unpause" command to resume a paused queue.
-
-Example: asynq pause default -> Pause the "default" queue`,
-	Args: cobra.ExactValidArgs(1),
-	Run:  pause,
-}
-
-func init() {
-	rootCmd.AddCommand(pauseCmd)
-}
-
-func pause(cmd *cobra.Command, args []string) {
-	c := redis.NewClient(&redis.Options{
-		Addr:     viper.GetString("uri"),
-		DB:       viper.GetInt("db"),
-		Password: viper.GetString("password"),
-	})
-	r := rdb.NewRDB(c)
-	err := r.Pause(args[0])
-	if err != nil {
-		fmt.Printf("error: %v\n", err)
-		os.Exit(1)
-	}
-	fmt.Printf("Successfully paused queue %q\n", args[0])
-}
--- a/tools/asynq/cmd/queue.go
+++ b/tools/asynq/cmd/queue.go
@@ -0,0 +1,256 @@
+// Copyright 2020 Kentaro Hibino. All rights reserved.
+// Use of this source code is governed by a MIT license
+// that can be found in the LICENSE file.
+
+package cmd
+
+import (
+	"fmt"
+	"io"
+	"os"
+
+	"github.com/fatih/color"
+	"github.com/hibiken/asynq"
+	"github.com/hibiken/asynq/internal/rdb"
+	"github.com/spf13/cobra"
+)
+
+const separator = "================================================="
+
+func init() {
+	rootCmd.AddCommand(queueCmd)
+	queueCmd.AddCommand(queueListCmd)
+	queueCmd.AddCommand(queueInspectCmd)
+	queueCmd.AddCommand(queueHistoryCmd)
+	queueHistoryCmd.Flags().IntP("days", "x", 10, "show data from last x days")
+
+	queueCmd.AddCommand(queuePauseCmd)
+	queueCmd.AddCommand(queueUnpauseCmd)
+	queueCmd.AddCommand(queueRemoveCmd)
+	queueRemoveCmd.Flags().BoolP("force", "f", false, "remove the queue regardless of its size")
+}
+
+var queueCmd = &cobra.Command{
+	Use:   "queue",
+	Short: "Manage queues",
+}
+
+var queueListCmd = &cobra.Command{
+	Use:   "ls",
+	Short: "List queues",
+	// TODO: Use RunE instead?
+	Run: queueList,
+}
+
+var queueInspectCmd = &cobra.Command{
+	Use:   "inspect QUEUE [QUEUE...]",
+	Short: "Display detailed information on one or more queues",
+	Args:  cobra.MinimumNArgs(1),
+	// TODO: Use RunE instead?
+	Run: queueInspect,
+}
+
+var queueHistoryCmd = &cobra.Command{
+	Use:   "history QUEUE [QUEUE...]",
+	Short: "Display historical aggregate data from one or more queues",
+	Args:  cobra.MinimumNArgs(1),
+	Run:   queueHistory,
+}
+
+var queuePauseCmd = &cobra.Command{
+	Use:   "pause QUEUE [QUEUE...]",
+	Short: "Pause one or more queues",
+	Args:  cobra.MinimumNArgs(1),
+	Run:   queuePause,
+}
+
+var queueUnpauseCmd = &cobra.Command{
+	Use:   "unpause QUEUE [QUEUE...]",
+	Short: "Unpause one or more queues",
+	Args:  cobra.MinimumNArgs(1),
+	Run:   queueUnpause,
+}
+
+var queueRemoveCmd = &cobra.Command{
+	Use:   "rm QUEUE [QUEUE...]",
+	Short: "Remove one or more queues",
+	Args:  cobra.MinimumNArgs(1),
+	Run:   queueRemove,
+}
+
+func queueList(cmd *cobra.Command, args []string) {
+	type queueInfo struct {
+		name    string
+		keyslot int64
+		nodes   []asynq.ClusterNode
+	}
+	inspector := createInspector()
+	queues, err := inspector.Queues()
+	if err != nil {
+		fmt.Printf("error: Could not fetch list of queues: %v\n", err)
+		os.Exit(1)
+	}
+	var qs []queueInfo
+	for _, qname := range queues {
+		q := queueInfo{name: qname}
+		if useRedisCluster {
+			keyslot, err := inspector.ClusterKeySlot(qname)
+			if err != nil {
+				fmt.Errorf("error: Could not get cluster keyslot for %q\n", qname)
+				continue
+			}
+			q.keyslot = keyslot
+			nodes, err := inspector.ClusterNodes(qname)
+			if err != nil {
+				fmt.Errorf("error: Could not get cluster nodes for %q\n", qname)
+				continue
+			}
+			q.nodes = nodes
+		}
+		qs = append(qs, q)
+	}
+	if useRedisCluster {
+		printTable(
+			[]string{"Queue", "Cluster KeySlot", "Cluster Nodes"},
+			func(w io.Writer, tmpl string) {
+				for _, q := range qs {
+					fmt.Fprintf(w, tmpl, q.name, q.keyslot, q.nodes)
+				}
+			},
+		)
+	} else {
+		for _, q := range qs {
+			fmt.Println(q.name)
+		}
+	}
+}
+
+func queueInspect(cmd *cobra.Command, args []string) {
+	inspector := createInspector()
+	for i, qname := range args {
+		if i > 0 {
+			fmt.Printf("\n%s\n", separator)
+		}
+		fmt.Println()
+		stats, err := inspector.CurrentStats(qname)
+		if err != nil {
+			fmt.Printf("error: %v\n", err)
+			continue
+		}
+		printQueueStats(stats)
+	}
+}
+
+func printQueueStats(s *asynq.QueueStats) {
+	bold := color.New(color.Bold)
+	bold.Println("Queue Info")
+	fmt.Printf("Name:   %s\n", s.Queue)
+	fmt.Printf("Size:   %d\n", s.Size)
+	fmt.Printf("Paused: %t\n\n", s.Paused)
+	bold.Println("Task Count by State")
+	printTable(
+		[]string{"active", "pending", "scheduled", "retry", "archived"},
+		func(w io.Writer, tmpl string) {
+			fmt.Fprintf(w, tmpl, s.Active, s.Pending, s.Scheduled, s.Retry, s.Archived)
+		},
+	)
+	fmt.Println()
+	bold.Printf("Daily Stats %s UTC\n", s.Timestamp.UTC().Format("2006-01-02"))
+	printTable(
+		[]string{"processed", "failed", "error rate"},
+		func(w io.Writer, tmpl string) {
+			var errRate string
+			if s.Processed == 0 {
+				errRate = "N/A"
+			} else {
+				errRate = fmt.Sprintf("%.2f%%", float64(s.Failed)/float64(s.Processed)*100)
+			}
+			fmt.Fprintf(w, tmpl, s.Processed, s.Failed, errRate)
+		},
+	)
+}
+
+func queueHistory(cmd *cobra.Command, args []string) {
+	days, err := cmd.Flags().GetInt("days")
+	if err != nil {
+		fmt.Printf("error: Internal error: %v\n", err)
+		os.Exit(1)
+	}
+	inspector := createInspector()
+	for i, qname := range args {
+		if i > 0 {
+			fmt.Printf("\n%s\n", separator)
+		}
+		fmt.Printf("\nQueue: %s\n\n", qname)
+		stats, err := inspector.History(qname, days)
+		if err != nil {
+			fmt.Printf("error: %v\n", err)
+			continue
+		}
+		printDailyStats(stats)
+	}
+}
+
+func printDailyStats(stats []*asynq.DailyStats) {
+	printTable(
+		[]string{"date (UTC)", "processed", "failed", "error rate"},
+		func(w io.Writer, tmpl string) {
+			for _, s := range stats {
+				var errRate string
+				if s.Processed == 0 {
+					errRate = "N/A"
+				} else {
+					errRate = fmt.Sprintf("%.2f%%", float64(s.Failed)/float64(s.Processed)*100)
+				}
+				fmt.Fprintf(w, tmpl, s.Date.Format("2006-01-02"), s.Processed, s.Failed, errRate)
+			}
+		},
+	)
+}
+
+func queuePause(cmd *cobra.Command, args []string) {
+	inspector := createInspector()
+	for _, qname := range args {
+		err := inspector.PauseQueue(qname)
+		if err != nil {
+			fmt.Println(err)
+			continue
+		}
+		fmt.Printf("Successfully paused queue %q\n", qname)
+	}
+}
+
+func queueUnpause(cmd *cobra.Command, args []string) {
+	inspector := createInspector()
+	for _, qname := range args {
+		err := inspector.UnpauseQueue(qname)
+		if err != nil {
+			fmt.Println(err)
+			continue
+		}
+		fmt.Printf("Successfully unpaused queue %q\n", qname)
+	}
+}
+
+func queueRemove(cmd *cobra.Command, args []string) {
+	// TODO: Use inspector once RemoveQueue become public API.
+	force, err := cmd.Flags().GetBool("force")
+	if err != nil {
+		fmt.Printf("error: Internal error: %v\n", err)
+		os.Exit(1)
+	}
+
+	r := createRDB()
+	for _, qname := range args {
+		err = r.RemoveQueue(qname, force)
+		if err != nil {
+			if _, ok := err.(*rdb.ErrQueueNotEmpty); ok {
+				fmt.Printf("error: %v\nIf you are sure you want to delete it, run 'asynq queue rm --force %s'\n", err, qname)
+				continue
+			}
+			fmt.Printf("error: %v\n", err)
+			continue
+		}
+		fmt.Printf("Successfully removed queue %q\n", qname)
+	}
+}
--- a/tools/asynq/cmd/rmq.go
+++ b/tools/asynq/cmd/rmq.go
@@ -1,54 +0,0 @@
-// Copyright 2020 Kentaro Hibino. All rights reserved.
-// Use of this source code is governed by a MIT license
-// that can be found in the LICENSE file.
-
-package cmd
-
-import (
-	"fmt"
-	"os"
-
-	"github.com/go-redis/redis/v7"
-	"github.com/hibiken/asynq/internal/rdb"
-	"github.com/spf13/cobra"
-	"github.com/spf13/viper"
-)
-
-// rmqCmd represents the rmq command
-var rmqCmd = &cobra.Command{
-	Use:   "rmq [queue name]",
-	Short: "Removes the specified queue",
-	Long: `Rmq (asynq rmq) will remove the specified queue.
-By default, it will remove the queue only if it's empty.
-Use --force option to override this behavior.
-
-Example: asynq rmq low -> Removes "low" queue`,
-	Args: cobra.ExactValidArgs(1),
-	Run:  rmq,
-}
-
-var rmqForce bool
-
-func init() {
-	rootCmd.AddCommand(rmqCmd)
-	rmqCmd.Flags().BoolVarP(&rmqForce, "force", "f", false, "remove the queue regardless of its size")
-}
-
-func rmq(cmd *cobra.Command, args []string) {
-	c := redis.NewClient(&redis.Options{
-		Addr:     viper.GetString("uri"),
-		DB:       viper.GetInt("db"),
-		Password: viper.GetString("password"),
-	})
-	r := rdb.NewRDB(c)
-	err := r.RemoveQueue(args[0], rmqForce)
-	if err != nil {
-		if _, ok := err.(*rdb.ErrQueueNotEmpty); ok {
-			fmt.Printf("error: %v\nIf you are sure you want to delete it, run 'asynq rmq --force %s'\n", err, args[0])
-			os.Exit(1)
-		}
-		fmt.Printf("error: %v", err)
-		os.Exit(1)
-	}
-	fmt.Printf("Successfully removed queue %q\n", args[0])
-}
--- a/tools/asynq/cmd/root.go
+++ b/tools/asynq/cmd/root.go
@@ -5,13 +5,17 @@
 package cmd

 import (
+	"crypto/tls"
 	"fmt"
 	"io"
 	"os"
 	"strings"
 	"text/tabwriter"

+	"github.com/go-redis/redis/v7"
+	"github.com/hibiken/asynq"
 	"github.com/hibiken/asynq/internal/base"
+	"github.com/hibiken/asynq/internal/rdb"
 	"github.com/spf13/cobra"

 	homedir "github.com/mitchellh/go-homedir"
@@ -20,10 +24,16 @@ import (

 var cfgFile string

-// Flags
-var uri string
-var db int
-var password string
+// Global flag variables
+var (
+	uri      string
+	db       int
+	password string
+
+	useRedisCluster bool
+	clusterAddrs    string
+	tlsServerName   string
+)

 // rootCmd represents the base command when called without any subcommands
 var rootCmd = &cobra.Command{
@@ -62,9 +72,19 @@ func init() {
 	rootCmd.PersistentFlags().StringVarP(&uri, "uri", "u", "127.0.0.1:6379", "redis server URI")
 	rootCmd.PersistentFlags().IntVarP(&db, "db", "n", 0, "redis database number (default is 0)")
 	rootCmd.PersistentFlags().StringVarP(&password, "password", "p", "", "password to use when connecting to redis server")
+	rootCmd.PersistentFlags().BoolVar(&useRedisCluster, "cluster", false, "connect to redis cluster")
+	rootCmd.PersistentFlags().StringVar(&clusterAddrs, "cluster_addrs",
+		"127.0.0.1:7000,127.0.0.1:7001,127.0.0.1:7002,127.0.0.1:7003,127.0.0.1:7004,127.0.0.1:7005",
+		"list of comma-separated redis server addresses")
+	rootCmd.PersistentFlags().StringVar(&tlsServerName, "tls_server",
+		"", "server name for TLS validation")
+	// Bind flags with config.
 	viper.BindPFlag("uri", rootCmd.PersistentFlags().Lookup("uri"))
 	viper.BindPFlag("db", rootCmd.PersistentFlags().Lookup("db"))
 	viper.BindPFlag("password", rootCmd.PersistentFlags().Lookup("password"))
+	viper.BindPFlag("cluster", rootCmd.PersistentFlags().Lookup("cluster"))
+	viper.BindPFlag("cluster_addrs", rootCmd.PersistentFlags().Lookup("cluster_addrs"))
+	viper.BindPFlag("tls_server", rootCmd.PersistentFlags().Lookup("tls_server"))
 }

 // initConfig reads in config file and ENV variables if set.
@@ -93,6 +113,56 @@ func initConfig() {
 	}
 }

+// createRDB creates a RDB instance using flag values and returns it.
+func createRDB() *rdb.RDB {
+	var c redis.UniversalClient
+	if useRedisCluster {
+		addrs := strings.Split(viper.GetString("cluster_addrs"), ",")
+		c = redis.NewClusterClient(&redis.ClusterOptions{
+			Addrs:     addrs,
+			Password:  viper.GetString("password"),
+			TLSConfig: getTLSConfig(),
+		})
+	} else {
+		c = redis.NewClient(&redis.Options{
+			Addr:      viper.GetString("uri"),
+			DB:        viper.GetInt("db"),
+			Password:  viper.GetString("password"),
+			TLSConfig: getTLSConfig(),
+		})
+	}
+	return rdb.NewRDB(c)
+}
+
+// createRDB creates a Inspector instance using flag values and returns it.
+func createInspector() *asynq.Inspector {
+	var connOpt asynq.RedisConnOpt
+	if useRedisCluster {
+		addrs := strings.Split(viper.GetString("cluster_addrs"), ",")
+		connOpt = asynq.RedisClusterClientOpt{
+			Addrs:     addrs,
+			Password:  viper.GetString("password"),
+			TLSConfig: getTLSConfig(),
+		}
+	} else {
+		connOpt = asynq.RedisClientOpt{
+			Addr:      viper.GetString("uri"),
+			DB:        viper.GetInt("db"),
+			Password:  viper.GetString("password"),
+			TLSConfig: getTLSConfig(),
+		}
+	}
+	return asynq.NewInspector(connOpt)
+}
+
+func getTLSConfig() *tls.Config {
+	tlsServer := viper.GetString("tls_server")
+	if tlsServer == "" {
+		return nil
+	}
+	return &tls.Config{ServerName: tlsServer}
+}
+
 // printTable is a helper function to print data in table format.
 //
 // cols is a list of headers and printRow specifies how to print rows.
--- a/tools/asynq/cmd/servers.go
+++ b/tools/asynq/cmd/servers.go
@@ -12,18 +12,24 @@ import (
 	"strings"
 	"time"

-	"github.com/go-redis/redis/v7"
-	"github.com/hibiken/asynq/internal/rdb"
 	"github.com/spf13/cobra"
-	"github.com/spf13/viper"
 )

-// serversCmd represents the servers command
-var serversCmd = &cobra.Command{
-	Use:   "servers",
-	Short: "Shows all running worker servers",
-	Long: `Servers (asynq servers) will show all running worker servers
-pulling tasks from the specified redis instance.
+func init() {
+	rootCmd.AddCommand(serverCmd)
+	serverCmd.AddCommand(serverListCmd)
+}
+
+var serverCmd = &cobra.Command{
+	Use:   "server",
+	Short: "Manage servers",
+}
+
+var serverListCmd = &cobra.Command{
+	Use:   "ls",
+	Short: "List servers",
+	Long: `Server list (asynq server ls) shows all running worker servers
+pulling tasks from the given redis instance.

 The command shows the following for each server:
 * Host and PID of the process in which the server is running
@@ -34,20 +40,11 @@ The command shows the following for each server:

 A "running" server is pulling tasks from queues and processing them.
 A "quiet" server is no longer pulling new tasks from queues`,
-	Args: cobra.NoArgs,
-	Run:  servers,
+	Run: serverList,
 }

-func init() {
-	rootCmd.AddCommand(serversCmd)
-}
-
-func servers(cmd *cobra.Command, args []string) {
-	r := rdb.NewRDB(redis.NewClient(&redis.Options{
-		Addr:     viper.GetString("uri"),
-		DB:       viper.GetInt("db"),
-		Password: viper.GetString("password"),
-	}))
+func serverList(cmd *cobra.Command, args []string) {
+	r := createRDB()

 	servers, err := r.ListServers()
 	if err != nil {
@@ -81,12 +78,6 @@ func servers(cmd *cobra.Command, args []string) {
 	printTable(cols, printRows)
 }

-// timeAgo takes a time and returns a string of the format "<duration> ago".
-func timeAgo(since time.Time) string {
-	d := time.Since(since).Round(time.Second)
-	return fmt.Sprintf("%v ago", d)
-}
-
 func formatQueues(qmap map[string]int) string {
 	// sort queues by priority and name
 	type queue struct {
@@ -116,3 +107,9 @@ func formatQueues(qmap map[string]int) string {
 	}
 	return b.String()
 }
+
+// timeAgo takes a time and returns a string of the format "<duration> ago".
+func timeAgo(since time.Time) string {
+	d := time.Since(since).Round(time.Second)
+	return fmt.Sprintf("%v ago", d)
+}
--- a/tools/asynq/cmd/stats.go
+++ b/tools/asynq/cmd/stats.go
@@ -6,15 +6,16 @@ package cmd

 import (
 	"fmt"
+	"io"
 	"os"
 	"strconv"
 	"strings"
 	"text/tabwriter"
+	"time"

-	"github.com/go-redis/redis/v7"
+	"github.com/fatih/color"
 	"github.com/hibiken/asynq/internal/rdb"
 	"github.com/spf13/cobra"
-	"github.com/spf13/viper"
 )

 // statsCmd represents the stats command
@@ -51,57 +52,93 @@ func init() {
 	// statsCmd.Flags().BoolP("toggle", "t", false, "Help message for toggle")
 }

+type AggregateStats struct {
+	Active    int
+	Pending   int
+	Scheduled int
+	Retry     int
+	Archived  int
+	Processed int
+	Failed    int
+	Timestamp time.Time
+}
+
 func stats(cmd *cobra.Command, args []string) {
-	c := redis.NewClient(&redis.Options{
-		Addr:     viper.GetString("uri"),
-		DB:       viper.GetInt("db"),
-		Password: viper.GetString("password"),
-	})
-	r := rdb.NewRDB(c)
+	r := createRDB()

-	stats, err := r.CurrentStats()
+	queues, err := r.AllQueues()
 	if err != nil {
 		fmt.Println(err)
 		os.Exit(1)
 	}
-	info, err := r.RedisInfo()
+
+	var aggStats AggregateStats
+	var stats []*rdb.Stats
+	for _, qname := range queues {
+		s, err := r.CurrentStats(qname)
+		if err != nil {
+			fmt.Println(err)
+			os.Exit(1)
+		}
+		aggStats.Active += s.Active
+		aggStats.Pending += s.Pending
+		aggStats.Scheduled += s.Scheduled
+		aggStats.Retry += s.Retry
+		aggStats.Archived += s.Archived
+		aggStats.Processed += s.Processed
+		aggStats.Failed += s.Failed
+		aggStats.Timestamp = s.Timestamp
+		stats = append(stats, s)
+	}
+	var info map[string]string
+	if useRedisCluster {
+		info, err = r.RedisClusterInfo()
+	} else {
+		info, err = r.RedisInfo()
+	}
 	if err != nil {
 		fmt.Println(err)
 		os.Exit(1)
 	}
-	fmt.Println("STATES")
-	printStates(stats)
+	bold := color.New(color.Bold)
+	bold.Println("Task Count by State")
+	printStatsByState(&aggStats)
 	fmt.Println()

-	fmt.Println("QUEUES")
-	printQueues(stats.Queues)
+	bold.Println("Task Count by Queue")
+	printStatsByQueue(stats)
 	fmt.Println()

-	fmt.Printf("STATS FOR %s UTC\n", stats.Timestamp.UTC().Format("2006-01-02"))
-	printStats(stats)
+	bold.Printf("Daily Stats %s UTC\n", aggStats.Timestamp.UTC().Format("2006-01-02"))
+	printSuccessFailureStats(&aggStats)
 	fmt.Println()

-	fmt.Println("REDIS INFO")
-	printInfo(info)
+	if useRedisCluster {
+		bold.Println("Redis Cluster Info")
+		printClusterInfo(info)
+	} else {
+		bold.Println("Redis Info")
+		printInfo(info)
+	}
 	fmt.Println()
 }

-func printStates(s *rdb.Stats) {
+func printStatsByState(s *AggregateStats) {
 	format := strings.Repeat("%v\t", 5) + "\n"
 	tw := new(tabwriter.Writer).Init(os.Stdout, 0, 8, 2, ' ', 0)
-	fmt.Fprintf(tw, format, "InProgress", "Enqueued", "Scheduled", "Retry", "Dead")
+	fmt.Fprintf(tw, format, "active", "pending", "scheduled", "retry", "archived")
 	fmt.Fprintf(tw, format, "----------", "--------", "---------", "-----", "----")
-	fmt.Fprintf(tw, format, s.InProgress, s.Enqueued, s.Scheduled, s.Retry, s.Dead)
+	fmt.Fprintf(tw, format, s.Active, s.Pending, s.Scheduled, s.Retry, s.Archived)
 	tw.Flush()
 }

-func printQueues(queues []*rdb.Queue) {
+func printStatsByQueue(stats []*rdb.Stats) {
 	var headers, seps, counts []string
-	for _, q := range queues {
-		title := queueTitle(q)
+	for _, s := range stats {
+		title := queueTitle(s)
 		headers = append(headers, title)
 		seps = append(seps, strings.Repeat("-", len(title)))
-		counts = append(counts, strconv.Itoa(q.Size))
+		counts = append(counts, strconv.Itoa(s.Size))
 	}
 	format := strings.Repeat("%v\t", len(headers)) + "\n"
 	tw := new(tabwriter.Writer).Init(os.Stdout, 0, 8, 2, ' ', 0)
@@ -111,19 +148,19 @@ func printQueues(queues []*rdb.Queue) {
 	tw.Flush()
 }

-func queueTitle(q *rdb.Queue) string {
+func queueTitle(s *rdb.Stats) string {
 	var b strings.Builder
-	b.WriteString(strings.Title(q.Name))
-	if q.Paused {
-		b.WriteString(" (Paused)")
+	b.WriteString(s.Queue)
+	if s.Paused {
+		b.WriteString(" (paused)")
 	}
 	return b.String()
 }

-func printStats(s *rdb.Stats) {
+func printSuccessFailureStats(s *AggregateStats) {
 	format := strings.Repeat("%v\t", 3) + "\n"
 	tw := new(tabwriter.Writer).Init(os.Stdout, 0, 8, 2, ' ', 0)
-	fmt.Fprintf(tw, format, "Processed", "Failed", "Error Rate")
+	fmt.Fprintf(tw, format, "processed", "failed", "error rate")
 	fmt.Fprintf(tw, format, "---------", "------", "----------")
 	var errrate string
 	if s.Processed == 0 {
@@ -138,7 +175,7 @@ func printStats(s *rdb.Stats) {
 func printInfo(info map[string]string) {
 	format := strings.Repeat("%v\t", 5) + "\n"
 	tw := new(tabwriter.Writer).Init(os.Stdout, 0, 8, 2, ' ', 0)
-	fmt.Fprintf(tw, format, "Version", "Uptime", "Connections", "Memory Usage", "Peak Memory Usage")
+	fmt.Fprintf(tw, format, "version", "uptime", "connections", "memory usage", "peak memory usage")
 	fmt.Fprintf(tw, format, "-------", "------", "-----------", "------------", "-----------------")
 	fmt.Fprintf(tw, format,
 		info["redis_version"],
@@ -150,6 +187,19 @@ func printInfo(info map[string]string) {
 	tw.Flush()
 }

+func printClusterInfo(info map[string]string) {
+	printTable(
+		[]string{"State", "Known Nodes", "Cluster Size"},
+		func(w io.Writer, tmpl string) {
+			fmt.Fprintf(w, tmpl,
+				strings.ToUpper(info["cluster_state"]),
+				info["cluster_known_nodes"],
+				info["cluster_size"],
+			)
+		},
+	)
+}
+
 func toInterfaceSlice(strs []string) []interface{} {
 	var res []interface{}
 	for _, s := range strs {
--- a/tools/asynq/cmd/task.go
+++ b/tools/asynq/cmd/task.go
@@ -0,0 +1,463 @@
+// Copyright 2020 Kentaro Hibino. All rights reserved.
+// Use of this source code is governed by a MIT license
+// that can be found in the LICENSE file.
+
+package cmd
+
+import (
+	"fmt"
+	"io"
+	"os"
+	"time"
+
+	"github.com/hibiken/asynq"
+	"github.com/spf13/cobra"
+)
+
+func init() {
+	rootCmd.AddCommand(taskCmd)
+	taskCmd.AddCommand(taskListCmd)
+	taskListCmd.Flags().StringP("queue", "q", "", "queue to inspect")
+	taskListCmd.Flags().StringP("state", "s", "", "state of the tasks to inspect")
+	taskListCmd.Flags().Int("page", 1, "page number")
+	taskListCmd.Flags().Int("size", 30, "page size")
+	taskListCmd.MarkFlagRequired("queue")
+	taskListCmd.MarkFlagRequired("state")
+
+	taskCmd.AddCommand(taskCancelCmd)
+
+	taskCmd.AddCommand(taskArchiveCmd)
+	taskArchiveCmd.Flags().StringP("queue", "q", "", "queue to which the task belongs")
+	taskArchiveCmd.Flags().StringP("key", "k", "", "key of the task")
+	taskArchiveCmd.MarkFlagRequired("queue")
+	taskArchiveCmd.MarkFlagRequired("key")
+
+	taskCmd.AddCommand(taskDeleteCmd)
+	taskDeleteCmd.Flags().StringP("queue", "q", "", "queue to which the task belongs")
+	taskDeleteCmd.Flags().StringP("key", "k", "", "key of the task")
+	taskDeleteCmd.MarkFlagRequired("queue")
+	taskDeleteCmd.MarkFlagRequired("key")
+
+	taskCmd.AddCommand(taskRunCmd)
+	taskRunCmd.Flags().StringP("queue", "q", "", "queue to which the task belongs")
+	taskRunCmd.Flags().StringP("key", "k", "", "key of the task")
+	taskRunCmd.MarkFlagRequired("queue")
+	taskRunCmd.MarkFlagRequired("key")
+
+	taskCmd.AddCommand(taskArchiveAllCmd)
+	taskArchiveAllCmd.Flags().StringP("queue", "q", "", "queue to which the tasks belong")
+	taskArchiveAllCmd.Flags().StringP("state", "s", "", "state of the tasks")
+	taskArchiveAllCmd.MarkFlagRequired("queue")
+	taskArchiveAllCmd.MarkFlagRequired("state")
+
+	taskCmd.AddCommand(taskDeleteAllCmd)
+	taskDeleteAllCmd.Flags().StringP("queue", "q", "", "queue to which the tasks belong")
+	taskDeleteAllCmd.Flags().StringP("state", "s", "", "state of the tasks")
+	taskDeleteAllCmd.MarkFlagRequired("queue")
+	taskDeleteAllCmd.MarkFlagRequired("state")
+
+	taskCmd.AddCommand(taskRunAllCmd)
+	taskRunAllCmd.Flags().StringP("queue", "q", "", "queue to which the tasks belong")
+	taskRunAllCmd.Flags().StringP("state", "s", "", "state of the tasks")
+	taskRunAllCmd.MarkFlagRequired("queue")
+	taskRunAllCmd.MarkFlagRequired("state")
+}
+
+var taskCmd = &cobra.Command{
+	Use:   "task",
+	Short: "Manage tasks",
+}
+
+var taskListCmd = &cobra.Command{
+	Use:   "ls --queue=QUEUE --state=STATE",
+	Short: "List tasks",
+	Long: `List tasks of the given state from the specified queue.
+
+The value for the state flag should be one of:
+- active
+- pending
+- scheduled
+- retry
+- archived
+
+List opeartion paginates the result set.
+By default, the command fetches the first 30 tasks.
+Use --page and --size flags to specify the page number and size.
+
+Example: 
+To list pending tasks from "default" queue, run
+  asynq task ls --queue=default --state=pending
+
+To list the tasks from the second page, run
+  asynq task ls --queue=default --state=pending --page=1`,
+	Run: taskList,
+}
+
+var taskCancelCmd = &cobra.Command{
+	Use:   "cancel TASK_ID [TASK_ID...]",
+	Short: "Cancel one or more active tasks",
+	Args:  cobra.MinimumNArgs(1),
+	Run:   taskCancel,
+}
+
+var taskArchiveCmd = &cobra.Command{
+	Use:   "archive --queue=QUEUE --key=KEY",
+	Short: "Archive a task with the given key",
+	Args:  cobra.NoArgs,
+	Run:   taskKill,
+}
+
+var taskDeleteCmd = &cobra.Command{
+	Use:   "delete --queue=QUEUE --key=KEY",
+	Short: "Delete a task with the given key",
+	Args:  cobra.NoArgs,
+	Run:   taskDelete,
+}
+
+var taskRunCmd = &cobra.Command{
+	Use:   "run --queue=QUEUE --key=KEY",
+	Short: "Run a task with the given key",
+	Args:  cobra.NoArgs,
+	Run:   taskRun,
+}
+
+var taskArchiveAllCmd = &cobra.Command{
+	Use:   "archive-all --queue=QUEUE --state=STATE",
+	Short: "Archive all tasks in the given state",
+	Args:  cobra.NoArgs,
+	Run:   taskArchiveAll,
+}
+
+var taskDeleteAllCmd = &cobra.Command{
+	Use:   "delete-all --queue=QUEUE --key=KEY",
+	Short: "Delete all tasks in the given state",
+	Args:  cobra.NoArgs,
+	Run:   taskDeleteAll,
+}
+
+var taskRunAllCmd = &cobra.Command{
+	Use:   "run-all --queue=QUEUE --key=KEY",
+	Short: "Run all tasks in the given state",
+	Args:  cobra.NoArgs,
+	Run:   taskRunAll,
+}
+
+func taskList(cmd *cobra.Command, args []string) {
+	qname, err := cmd.Flags().GetString("queue")
+	if err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+	state, err := cmd.Flags().GetString("state")
+	if err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+	pageNum, err := cmd.Flags().GetInt("page")
+	if err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+	pageSize, err := cmd.Flags().GetInt("size")
+	if err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+
+	switch state {
+	case "active":
+		listActiveTasks(qname, pageNum, pageSize)
+	case "pending":
+		listPendingTasks(qname, pageNum, pageSize)
+	case "scheduled":
+		listScheduledTasks(qname, pageNum, pageSize)
+	case "retry":
+		listRetryTasks(qname, pageNum, pageSize)
+	case "archived":
+		listArchivedTasks(qname, pageNum, pageSize)
+	default:
+		fmt.Printf("error: state=%q is not supported\n", state)
+		os.Exit(1)
+	}
+}
+
+func listActiveTasks(qname string, pageNum, pageSize int) {
+	i := createInspector()
+	tasks, err := i.ListActiveTasks(qname, asynq.PageSize(pageSize), asynq.Page(pageNum))
+	if err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+	if len(tasks) == 0 {
+		fmt.Printf("No active tasks in %q queue\n", qname)
+		return
+	}
+	printTable(
+		[]string{"ID", "Type", "Payload"},
+		func(w io.Writer, tmpl string) {
+			for _, t := range tasks {
+				fmt.Fprintf(w, tmpl, t.ID, t.Type, t.Payload)
+			}
+		},
+	)
+}
+
+func listPendingTasks(qname string, pageNum, pageSize int) {
+	i := createInspector()
+	tasks, err := i.ListPendingTasks(qname, asynq.PageSize(pageSize), asynq.Page(pageNum))
+	if err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+	if len(tasks) == 0 {
+		fmt.Printf("No pending tasks in %q queue\n", qname)
+		return
+	}
+	printTable(
+		[]string{"ID", "Type", "Payload"},
+		func(w io.Writer, tmpl string) {
+			for _, t := range tasks {
+				fmt.Fprintf(w, tmpl, t.ID, t.Type, t.Payload)
+			}
+		},
+	)
+}
+
+func listScheduledTasks(qname string, pageNum, pageSize int) {
+	i := createInspector()
+	tasks, err := i.ListScheduledTasks(qname, asynq.PageSize(pageSize), asynq.Page(pageNum))
+	if err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+	if len(tasks) == 0 {
+		fmt.Printf("No scheduled tasks in %q queue\n", qname)
+		return
+	}
+	printTable(
+		[]string{"Key", "Type", "Payload", "Process In"},
+		func(w io.Writer, tmpl string) {
+			for _, t := range tasks {
+				processIn := fmt.Sprintf("%.0f seconds",
+					t.NextProcessAt.Sub(time.Now()).Seconds())
+				fmt.Fprintf(w, tmpl, t.Key(), t.Type, t.Payload, processIn)
+			}
+		},
+	)
+}
+
+func listRetryTasks(qname string, pageNum, pageSize int) {
+	i := createInspector()
+	tasks, err := i.ListRetryTasks(qname, asynq.PageSize(pageSize), asynq.Page(pageNum))
+	if err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+	if len(tasks) == 0 {
+		fmt.Printf("No retry tasks in %q queue\n", qname)
+		return
+	}
+	printTable(
+		[]string{"Key", "Type", "Payload", "Next Retry", "Last Error", "Retried", "Max Retry"},
+		func(w io.Writer, tmpl string) {
+			for _, t := range tasks {
+				var nextRetry string
+				if d := t.NextProcessAt.Sub(time.Now()); d > 0 {
+					nextRetry = fmt.Sprintf("in %v", d.Round(time.Second))
+				} else {
+					nextRetry = "right now"
+				}
+				fmt.Fprintf(w, tmpl, t.Key(), t.Type, t.Payload, nextRetry, t.ErrorMsg, t.Retried, t.MaxRetry)
+			}
+		},
+	)
+}
+
+func listArchivedTasks(qname string, pageNum, pageSize int) {
+	i := createInspector()
+	tasks, err := i.ListArchivedTasks(qname, asynq.PageSize(pageSize), asynq.Page(pageNum))
+	if err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+	if len(tasks) == 0 {
+		fmt.Printf("No archived tasks in %q queue\n", qname)
+		return
+	}
+	printTable(
+		[]string{"Key", "Type", "Payload", "Last Failed", "Last Error"},
+		func(w io.Writer, tmpl string) {
+			for _, t := range tasks {
+				fmt.Fprintf(w, tmpl, t.Key(), t.Type, t.Payload, t.LastFailedAt, t.ErrorMsg)
+			}
+		})
+}
+
+func taskCancel(cmd *cobra.Command, args []string) {
+	r := createRDB()
+	for _, id := range args {
+		err := r.PublishCancelation(id)
+		if err != nil {
+			fmt.Printf("error: could not send cancelation signal: %v\n", err)
+			continue
+		}
+		fmt.Printf("Sent cancelation signal for task %s\n", id)
+	}
+}
+
+func taskKill(cmd *cobra.Command, args []string) {
+	qname, err := cmd.Flags().GetString("queue")
+	if err != nil {
+		fmt.Printf("error: %v\n", err)
+		os.Exit(1)
+	}
+	key, err := cmd.Flags().GetString("key")
+	if err != nil {
+		fmt.Printf("error: %v\n", err)
+		os.Exit(1)
+	}
+
+	i := createInspector()
+	err = i.ArchiveTaskByKey(qname, key)
+	if err != nil {
+		fmt.Printf("error: %v\n", err)
+		os.Exit(1)
+	}
+	fmt.Println("task transitioned to archived state")
+}
+
+func taskDelete(cmd *cobra.Command, args []string) {
+	qname, err := cmd.Flags().GetString("queue")
+	if err != nil {
+		fmt.Printf("error: %v\n", err)
+		os.Exit(1)
+	}
+	key, err := cmd.Flags().GetString("key")
+	if err != nil {
+		fmt.Printf("error: %v\n", err)
+		os.Exit(1)
+	}
+
+	i := createInspector()
+	err = i.DeleteTaskByKey(qname, key)
+	if err != nil {
+		fmt.Printf("error: %v\n", err)
+		os.Exit(1)
+	}
+	fmt.Println("task deleted")
+}
+
+func taskRun(cmd *cobra.Command, args []string) {
+	qname, err := cmd.Flags().GetString("queue")
+	if err != nil {
+		fmt.Printf("error: %v\n", err)
+		os.Exit(1)
+	}
+	key, err := cmd.Flags().GetString("key")
+	if err != nil {
+		fmt.Printf("error: %v\n", err)
+		os.Exit(1)
+	}
+
+	i := createInspector()
+	err = i.RunTaskByKey(qname, key)
+	if err != nil {
+		fmt.Printf("error: %v\n", err)
+		os.Exit(1)
+	}
+	fmt.Println("task transitioned to pending state")
+}
+
+func taskArchiveAll(cmd *cobra.Command, args []string) {
+	qname, err := cmd.Flags().GetString("queue")
+	if err != nil {
+		fmt.Printf("error: %v\n", err)
+		os.Exit(1)
+	}
+	state, err := cmd.Flags().GetString("state")
+	if err != nil {
+		fmt.Printf("error: %v\n", err)
+		os.Exit(1)
+	}
+
+	i := createInspector()
+	var n int
+	switch state {
+	case "scheduled":
+		n, err = i.ArchiveAllScheduledTasks(qname)
+	case "retry":
+		n, err = i.ArchiveAllRetryTasks(qname)
+	default:
+		fmt.Printf("error: unsupported state %q\n", state)
+		os.Exit(1)
+	}
+	if err != nil {
+		fmt.Printf("error: %v\n", err)
+		os.Exit(1)
+	}
+	fmt.Printf("%d tasks transitioned to archived state\n", n)
+}
+
+func taskDeleteAll(cmd *cobra.Command, args []string) {
+	qname, err := cmd.Flags().GetString("queue")
+	if err != nil {
+		fmt.Printf("error: %v\n", err)
+		os.Exit(1)
+	}
+	state, err := cmd.Flags().GetString("state")
+	if err != nil {
+		fmt.Printf("error: %v\n", err)
+		os.Exit(1)
+	}
+
+	i := createInspector()
+	var n int
+	switch state {
+	case "scheduled":
+		n, err = i.DeleteAllScheduledTasks(qname)
+	case "retry":
+		n, err = i.DeleteAllRetryTasks(qname)
+	case "archived":
+		n, err = i.DeleteAllArchivedTasks(qname)
+	default:
+		fmt.Printf("error: unsupported state %q\n", state)
+		os.Exit(1)
+	}
+	if err != nil {
+		fmt.Printf("error: %v\n", err)
+		os.Exit(1)
+	}
+	fmt.Printf("%d tasks deleted\n", n)
+}
+
+func taskRunAll(cmd *cobra.Command, args []string) {
+	qname, err := cmd.Flags().GetString("queue")
+	if err != nil {
+		fmt.Printf("error: %v\n", err)
+		os.Exit(1)
+	}
+	state, err := cmd.Flags().GetString("state")
+	if err != nil {
+		fmt.Printf("error: %v\n", err)
+		os.Exit(1)
+	}
+
+	i := createInspector()
+	var n int
+	switch state {
+	case "scheduled":
+		n, err = i.RunAllScheduledTasks(qname)
+	case "retry":
+		n, err = i.RunAllRetryTasks(qname)
+	case "archived":
+		n, err = i.RunAllArchivedTasks(qname)
+	default:
+		fmt.Printf("error: unsupported state %q\n", state)
+		os.Exit(1)
+	}
+	if err != nil {
+		fmt.Printf("error: %v\n", err)
+		os.Exit(1)
+	}
+	fmt.Printf("%d tasks transitioned to pending state\n", n)
+}
--- a/tools/asynq/cmd/unpause.go
+++ b/tools/asynq/cmd/unpause.go
@@ -1,46 +0,0 @@
-// Copyright 2020 Kentaro Hibino. All rights reserved.
-// Use of this source code is governed by a MIT license
-// that can be found in the LICENSE file.
-
-package cmd
-
-import (
-	"fmt"
-	"os"
-
-	"github.com/go-redis/redis/v7"
-	"github.com/hibiken/asynq/internal/rdb"
-	"github.com/spf13/cobra"
-	"github.com/spf13/viper"
-)
-
-// unpauseCmd represents the unpause command
-var unpauseCmd = &cobra.Command{
-	Use:   "unpause [queue name]",
-	Short: "Unpauses the specified queue",
-	Long: `Unpause (asynq unpause) will unpause the specified queue.
-Asynq servers will process tasks from unpaused/resumed queues.
-
-Example: asynq unpause default -> Resume the "default" queue`,
-	Args: cobra.ExactValidArgs(1),
-	Run:  unpause,
-}
-
-func init() {
-	rootCmd.AddCommand(unpauseCmd)
-}
-
-func unpause(cmd *cobra.Command, args []string) {
-	c := redis.NewClient(&redis.Options{
-		Addr:     viper.GetString("uri"),
-		DB:       viper.GetInt("db"),
-		Password: viper.GetString("password"),
-	})
-	r := rdb.NewRDB(c)
-	err := r.Unpause(args[0])
-	if err != nil {
-		fmt.Printf("error: %v\n", err)
-		os.Exit(1)
-	}
-	fmt.Printf("Successfully resumed queue %q\n", args[0])
-}
--- a/tools/asynq/cmd/workers.go
+++ b/tools/asynq/cmd/workers.go
@@ -1,75 +0,0 @@
-// Copyright 2020 Kentaro Hibino. All rights reserved.
-// Use of this source code is governed by a MIT license
-// that can be found in the LICENSE file.
-
-package cmd
-
-import (
-	"fmt"
-	"io"
-	"os"
-	"sort"
-
-	"github.com/go-redis/redis/v7"
-	"github.com/hibiken/asynq/internal/rdb"
-	"github.com/spf13/cobra"
-	"github.com/spf13/viper"
-)
-
-// workersCmd represents the workers command
-var workersCmd = &cobra.Command{
-	Use:   "workers",
-	Short: "Shows all running workers information",
-	Long: `Workers (asynq workers) will show all running workers information.
-
-The command shows the following for each worker:
-* Process in which the worker is running
-* ID of the task worker is processing
-* Type of the task worker is processing
-* Payload of the task worker is processing
-* Queue that the task was pulled from.
-* Time the worker started processing the task`,
-	Args: cobra.NoArgs,
-	Run:  workers,
-}
-
-func init() {
-	rootCmd.AddCommand(workersCmd)
-}
-
-func workers(cmd *cobra.Command, args []string) {
-	r := rdb.NewRDB(redis.NewClient(&redis.Options{
-		Addr:     viper.GetString("uri"),
-		DB:       viper.GetInt("db"),
-		Password: viper.GetString("password"),
-	}))
-
-	workers, err := r.ListWorkers()
-	if err != nil {
-		fmt.Println(err)
-		os.Exit(1)
-	}
-
-	if len(workers) == 0 {
-		fmt.Println("No workers")
-		return
-	}
-
-	// sort by started timestamp or ID.
-	sort.Slice(workers, func(i, j int) bool {
-		x, y := workers[i], workers[j]
-		if x.Started != y.Started {
-			return x.Started.Before(y.Started)
-		}
-		return x.ID < y.ID
-	})
-
-	cols := []string{"Process", "ID", "Type", "Payload", "Queue", "Started"}
-	printRows := func(w io.Writer, tmpl string) {
-		for _, wk := range workers {
-			fmt.Fprintf(w, tmpl,
-				fmt.Sprintf("%s:%d", wk.Host, wk.PID), wk.ID, wk.Type, wk.Payload, wk.Queue, timeAgo(wk.Started))
-		}
-	}
-	printTable(cols, printRows)
-}
--- a/tools/go.mod
+++ b/tools/go.mod
@@ -3,13 +3,17 @@ module github.com/hibiken/asynq/tools
 go 1.13

 require (
-	github.com/go-redis/redis/v7 v7.2.0
+	github.com/coreos/go-etcd v2.0.0+incompatible // indirect
+	github.com/cpuguy83/go-md2man v1.0.10 // indirect
+	github.com/fatih/color v1.9.0
+	github.com/go-redis/redis/v7 v7.4.0
 	github.com/google/uuid v1.1.1
 	github.com/hibiken/asynq v0.4.0
 	github.com/mitchellh/go-homedir v1.1.0
 	github.com/spf13/cast v1.3.1
-	github.com/spf13/cobra v0.0.5
+	github.com/spf13/cobra v1.0.0
 	github.com/spf13/viper v1.6.2
+	github.com/ugorji/go/codec v0.0.0-20181204163529-d75b2dcb6bc8 // indirect
 )

 replace github.com/hibiken/asynq => ./..
--- a/tools/go.sum
+++ b/tools/go.sum
@@ -16,10 +16,13 @@ github.com/coreos/go-semver v0.2.0/go.mod h1:nnelYz7RCh+5ahJtPPxZlU+153eP4D4r3Ee
 github.com/coreos/go-systemd v0.0.0-20190321100706-95778dfbb74e/go.mod h1:F5haX7vjVVG0kc13fIWeqUViNPyEJxv/OmvnBo0Yme4=
 github.com/coreos/pkg v0.0.0-20180928190104-399ea9e2e55f/go.mod h1:E3G3o1h8I7cfcXa63jLwjI0eiQQMgzzUDFVpN/nH/eA=
 github.com/cpuguy83/go-md2man v1.0.10/go.mod h1:SmD6nW6nTyfqj6ABTjUi3V3JVMnlJmwcJI5acqYI6dE=
+github.com/cpuguy83/go-md2man/v2 v2.0.0/go.mod h1:maD7wRr/U5Z6m/iR4s+kqSMx2CaBsrgA7czyZG/E6dU=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/dgrijalva/jwt-go v3.2.0+incompatible/go.mod h1:E3ru+11k8xSBh+hMPgOLZmtrrCbhqsmaPHjLKYnJCaQ=
 github.com/dgryski/go-sip13 v0.0.0-20181026042036-e10d5fee7954/go.mod h1:vAd38F8PWV+bWy6jNmig1y/TA+kYO4g3RSRF0IAv0no=
+github.com/fatih/color v1.9.0 h1:8xPHl4/q1VyqGIPif1F+1V3Y3lSmrq01EabUW3CoW5s=
+github.com/fatih/color v1.9.0/go.mod h1:eQcE1qtQxscV5RaZvpXrrb8Drkc3/DdQ+uUYCNjL+zU=
 github.com/fsnotify/fsnotify v1.4.7 h1:IXs+QLmnXW2CcXuY+8Mzv/fWEsPGWxqefPtCP5CnV9I=
 github.com/fsnotify/fsnotify v1.4.7/go.mod h1:jwhsz4b93w/PPRr/qN1Yymfu8t87LnFCMoQvtojpjFo=
 github.com/ghodss/yaml v1.0.0/go.mod h1:4dBDuWmgqj2HViK6kFavaiC9ZROes6MMH2rRYeMEF04=
@@ -28,6 +31,8 @@ github.com/go-logfmt/logfmt v0.3.0/go.mod h1:Qt1PoO58o5twSAckw1HlFXLmHsOX5/0LbT9
 github.com/go-logfmt/logfmt v0.4.0/go.mod h1:3RMwSq7FuexP4Kalkev3ejPJsZTpXXBr9+V4qmtdjCk=
 github.com/go-redis/redis/v7 v7.2.0 h1:CrCexy/jYWZjW0AyVoHlcJUeZN19VWlbepTh1Vq6dJs=
 github.com/go-redis/redis/v7 v7.2.0/go.mod h1:JDNMw23GTyLNC4GZu9njt15ctBQVn7xjRfnwdHj/Dcg=
+github.com/go-redis/redis/v7 v7.4.0 h1:7obg6wUoj05T0EpY0o8B59S9w5yeMWql7sw2kwNW1x4=
+github.com/go-redis/redis/v7 v7.4.0/go.mod h1:JDNMw23GTyLNC4GZu9njt15ctBQVn7xjRfnwdHj/Dcg=
 github.com/go-stack/stack v1.8.0/go.mod h1:v0f6uXyyMGvRgIKkXu+yp6POWl0qKG85gN/melR3HDY=
 github.com/gogo/protobuf v1.1.1/go.mod h1:r8qH/GZQm5c6nD/R0oafs1akxWv10x8SbQlK7atdtwQ=
 github.com/gogo/protobuf v1.2.1/go.mod h1:hp+jE20tsWTFYpLwKvXlhS1hjn+gTNwPg2I6zVXpSg4=
@@ -72,6 +77,11 @@ github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
 github.com/magiconair/properties v1.8.0/go.mod h1:PppfXfuXeibc/6YijjN8zIbojt8czPbwD3XqdrwzmxQ=
 github.com/magiconair/properties v1.8.1 h1:ZC2Vc7/ZFkGmsVC9KvOjumD+G5lXy2RtTKyzRKO2BQ4=
 github.com/magiconair/properties v1.8.1/go.mod h1:PppfXfuXeibc/6YijjN8zIbojt8czPbwD3XqdrwzmxQ=
+github.com/mattn/go-colorable v0.1.4 h1:snbPLB8fVfU9iwbbo30TPtbLRzwWu6aJS6Xh4eaaviA=
+github.com/mattn/go-colorable v0.1.4/go.mod h1:U0ppj6V5qS13XJ6of8GYAs25YV2eR4EVcfRqFIhoBtE=
+github.com/mattn/go-isatty v0.0.8/go.mod h1:Iq45c/XA43vh69/j3iqttzPXn0bhXyGjM0Hdxcsrc5s=
+github.com/mattn/go-isatty v0.0.11 h1:FxPOTFNqGkuDUGi3H/qkUbQO4ZiBa2brKq5r0l8TGeM=
+github.com/mattn/go-isatty v0.0.11/go.mod h1:PhnuNfih5lzO57/f3n+odYbM4JtupLOxQOAqxQCu2WE=
 github.com/matttproud/golang_protobuf_extensions v1.0.1/go.mod h1:D8He9yQNgCq6Z5Ld7szi9bcBfOoFv/3dc6xSMkL2PC0=
 github.com/mitchellh/go-homedir v1.1.0 h1:lukF9ziXFxDFPkA1vsr5zpc1XuPDn/wFntq5mG+4E0Y=
 github.com/mitchellh/go-homedir v1.1.0/go.mod h1:SfyaCUpYCn1Vlf4IUYiD9fPX4A5wJrkLzIz1N1q0pr0=
@@ -98,8 +108,12 @@ github.com/prometheus/common v0.4.0/go.mod h1:TNfzLD0ON7rHzMJeJkieUDPYmFC7Snx/y8
 github.com/prometheus/procfs v0.0.0-20181005140218-185b4288413d/go.mod h1:c3At6R/oaqEKCNdg8wHV1ftS6bRYblBhIjjI8uT2IGk=
 github.com/prometheus/procfs v0.0.0-20190507164030-5867b95ac084/go.mod h1:TjEm7ze935MbeOT/UhFTIMYKhuLP4wbCsTZCD3I8kEA=
 github.com/prometheus/tsdb v0.7.1/go.mod h1:qhTCs0VvXwvX/y3TZrWD7rabWM+ijKTux40TwIPHuXU=
+github.com/robfig/cron/v3 v3.0.1 h1:WdRxkvbJztn8LMz/QEvLN5sBU+xKpSqwwUO1Pjr4qDs=
+github.com/robfig/cron/v3 v3.0.1/go.mod h1:eQICP3HwyT7UooqI/z+Ov+PtYAWygg1TEWWzGIFLtro=
 github.com/rogpeppe/fastuuid v0.0.0-20150106093220-6724a57986af/go.mod h1:XWv6SoW27p1b0cqNHllgS5HIMJraePCO15w5zCzIWYg=
 github.com/russross/blackfriday v1.5.2/go.mod h1:JO/DiYxRf+HjHt06OyowR9PTA263kcR/rfWxYHBV53g=
+github.com/russross/blackfriday/v2 v2.0.1/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQDYRxCVz55jmeOWTM=
+github.com/shurcooL/sanitized_anchor_name v1.0.0/go.mod h1:1NzhyTcUVG4SuEtjjoZeVRXNmyL/1OwPU0+IJeTBvfc=
 github.com/sirupsen/logrus v1.2.0/go.mod h1:LxeOpSwHxABJmUn/MG1IvRgCAasNZTLOkJPxbbu5VWo=
 github.com/smartystreets/assertions v0.0.0-20180927180507-b2de0cb4f26d h1:zE9ykElWQ6/NYmHa3jpm/yHnI4xSofP+UP6SpjHcSeM=
 github.com/smartystreets/assertions v0.0.0-20180927180507-b2de0cb4f26d/go.mod h1:OnSkiWE9lh6wB0YB77sQom3nweQdgAjqCqsofrRNTgc=
@@ -114,11 +128,14 @@ github.com/spf13/cast v1.3.1 h1:nFm6S0SMdyzrzcmThSipiEubIDy8WEXKNZ0UOgiRpng=
 github.com/spf13/cast v1.3.1/go.mod h1:Qx5cxh0v+4UWYiBimWS+eyWzqEqokIECu5etghLkUJE=
 github.com/spf13/cobra v0.0.5 h1:f0B+LkLX6DtmRH1isoNA9VTtNUK9K8xYd28JNNfOv/s=
 github.com/spf13/cobra v0.0.5/go.mod h1:3K3wKZymM7VvHMDS9+Akkh4K60UwM26emMESw8tLCHU=
+github.com/spf13/cobra v1.0.0 h1:6m/oheQuQ13N9ks4hubMG6BnvwOeaJrqSPLahSnczz8=
+github.com/spf13/cobra v1.0.0/go.mod h1:/6GTrnGXV9HjY+aR4k0oJ5tcvakLuG6EuKReYlHNrgE=
 github.com/spf13/jwalterweatherman v1.0.0 h1:XHEdyB+EcvlqZamSM4ZOMGlc93t6AcsBEu9Gc1vn7yk=
 github.com/spf13/jwalterweatherman v1.0.0/go.mod h1:cQK4TGJAtQXfYWX+Ddv3mKDzgVb68N+wFjFa4jdeBTo=
 github.com/spf13/pflag v1.0.3 h1:zPAT6CGy6wXeQ7NtTnaTerfKOsV6V6F8agHXFiazDkg=
 github.com/spf13/pflag v1.0.3/go.mod h1:DYY7MBk1bdzusC3SYhjObp+wFpr4gzcvqqNjLnInEg4=
 github.com/spf13/viper v1.3.2/go.mod h1:ZiWeW+zYFKm7srdB9IoDzzZXaJaI5eL9QjNiN/DMA2s=
+github.com/spf13/viper v1.4.0/go.mod h1:PTJ7Z/lr49W6bUbkmS1V3by4uWynFiR9p7+dSq/yZzE=
 github.com/spf13/viper v1.6.2 h1:7aKfF+e8/k68gda3LOjo5RxiUqddoFxVq4BKBPrxk5E=
 github.com/spf13/viper v1.6.2/go.mod h1:t3iDnF5Jlj76alVNuyFBk5oUMCvsrkbvZK0WQdfDi5k=
 github.com/stretchr/objx v0.1.1/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
@@ -160,12 +177,15 @@ golang.org/x/sys v0.0.0-20181107165924-66b7b1311ac8/go.mod h1:STP8DvDyc/dI5b8T5h
 golang.org/x/sys v0.0.0-20181116152217-5ac8a444bdc5/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20181205085412-a5c9d58dba9a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/sys v0.0.0-20190222072716-a9d3bda3a223/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20191010194322-b09406accb47/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20191026070338-33540a1f6037/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20191204072324-ce4227a45e2e h1:9vRrk9YW2BTzLP0VCB9ZDjU4cPqkg+IDWL7XgxA1yxQ=
 golang.org/x/sys v0.0.0-20191204072324-ce4227a45e2e/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.2 h1:tW2bmiBqwgJj/UpqtC8EpXEZVYOwU0yG4iWbprSVAcs=
 golang.org/x/text v0.3.2/go.mod h1:bEr9sfX3Q8Zfm5fL9x+3itogRgK3+ptLWKqgva+5dAk=
+golang.org/x/time v0.0.0-20190308202827-9d24e82272b4 h1:SvFZT6jyqRaOeXpc5h/JSfZenJ2O330aBsf7JfSUXmQ=
 golang.org/x/time v0.0.0-20190308202827-9d24e82272b4/go.mod h1:tRJNPiyCQ0inRvYxbN9jk5I+vvW/OXSQhTDSoE431IQ=
 golang.org/x/tools v0.0.0-20180221164845-07fd8470d635/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
Author	SHA1	Message	Date
Ken Hibino	42c7ac0746	v0.14.0	2021-01-14 06:49:36 -08:00
Ken Hibino	d331ff055d	Minor doc fixes	2021-01-14 06:43:44 -08:00
Ken Hibino	ccb682853e	Export DefaultRetryDelayFunc	2021-01-14 06:43:44 -08:00
Ken Hibino	7c3ad9e45c	Update CHANGELOG	2021-01-14 06:43:44 -08:00
Ken Hibino	ea23db4f6b	Update migrate command to move all dead tasks to the new archived zset	2021-01-14 06:43:44 -08:00
Ken Hibino	00a25ca570	Rename DeadTask to ArchivedTask and action "kill" to "archive"	2021-01-14 06:43:44 -08:00
Ken Hibino	7235041128	Add SkipRetry error to be used as a return value from Handler	2021-01-14 06:43:44 -08:00
Ken Hibino	a150d18ed7	Include file and line number info in the error generated from a panic	2021-01-14 06:43:44 -08:00
Ken Hibino	0712e90f23	Print stack track when recovering from a panic in processor	2021-01-14 06:43:44 -08:00
Ken Hibino	c5100a9c23	Add a method to list running servers to Inspector	2021-01-14 06:43:44 -08:00
Ken Hibino	196d66f221	Fix ListSchedulerEnqueueEvents to list recent events first	2021-01-14 06:43:44 -08:00
Ken Hibino	38509e309f	Update `cron history` command to accept pagination options	2021-01-14 06:43:44 -08:00
Ken Hibino	f4dd8fe962	Add ListScheduelerEnqueueEvents to Inspector	2021-01-14 06:43:44 -08:00
Ken Hibino	c06e9de97d	Add CancelActiveTask method to Inspector	2021-01-14 06:43:44 -08:00
Ken Hibino	52d536a8f5	Update changelog	2021-01-14 06:43:44 -08:00
Ken Hibino	f9c0673116	Add SchedulerEntries method to Inspector	2021-01-14 06:43:44 -08:00
Ken Hibino	b604d25937	Add helper function to parse Option string	2021-01-14 06:43:44 -08:00
Ken Hibino	dfdf530a24	Fix cron history command usage string	2021-01-14 06:43:44 -08:00
Ken Hibino	e9239260ae	Add DeleteQueue method to Inspector - Added ErrQueueNotFound and ErrQueueNotEmpty type to indicate the kind of an error returned from the method.	2021-01-14 06:43:44 -08:00
Bojan Zivanovic	8f9d5a3352	When a scheduler enqueues a task, log to DEBUG, not INFO. Fixes #223 .	2021-01-13 15:49:56 -08:00
MinJae Kwon	c4dc993241	fix: resolve go vet lint	2020-12-20 06:09:51 -08:00
MinJae Kwon	37dfd746d4	fix: syntax error in readme example	2020-12-17 06:05:16 -08:00
Ken Hibino	8d6e4167ab	Fix a typo in readme	2020-11-25 06:11:55 -08:00
Ken Hibino	476862dd7b	v0.13.1	2020-11-22 12:26:52 -08:00
Ken Hibino	dcd873fa2a	fix: Wait for specified time duration before shutdown	2020-11-22 12:25:27 -08:00
strobus	2604bb2192	add tls support to command line tool	2020-10-14 15:13:05 -07:00
Ken Hibino	942345ee80	v0.13.0	2020-10-13 06:33:47 -07:00
Ken Hibino	1f059eeee1	Update docs for periodic tasks feature	2020-10-13 06:31:47 -07:00
Ken Hibino	4ae73abdaa	Minor update to asynq cron command	2020-10-13 06:31:47 -07:00
Ken Hibino	96b2318300	Add EnqueueErrorHandler option to SchedulerOpts	2020-10-13 06:31:47 -07:00
Ken Hibino	8312515e64	Update Option interface - Added `String()`, `Type()`, and `Value()` methods to the interface to aid with debugging and error handling.	2020-10-13 06:31:47 -07:00
Ken Hibino	50e7f38365	Add Scheduler - Renamed previously called scheduler to forwarder to resolve name conflicts	2020-10-13 06:31:47 -07:00
Ken Hibino	fadcae76d6	Add String and MarshalJSON methods to Payload type	2020-09-20 07:33:23 -07:00
Ken Hibino	a2d4ead989	Fix comments in Config	2020-09-14 21:48:05 -07:00
Ken Hibino	82b6828f43	Replace benchcmp with benchstat	2020-09-14 06:59:55 -07:00
Ken Hibino	3114987428	v0.12.0	2020-09-12 13:34:27 -07:00
Ken Hibino	1ee3b10104	Update changelog	2020-09-12 12:59:03 -07:00
Ken Hibino	6d720d6a05	Update demo.gif for CLI demo	2020-09-12 12:59:03 -07:00
Ken Hibino	3e6981170d	Use color package to bold fonts in CLI output	2020-09-12 12:59:03 -07:00
Ken Hibino	a9aa480551	Update migrate command	2020-09-12 12:59:03 -07:00
Ken Hibino	9d41de795a	Mention about testing using redis cluster in CONTRIBUTING.md	2020-09-12 12:59:03 -07:00
Ken Hibino	c43fb21a0a	Minor test updates	2020-09-12 12:59:03 -07:00
Ken Hibino	a293efcdab	Add Close to Inspector	2020-09-12 12:59:03 -07:00
Ken Hibino	69d7ec725a	Close redis client after each test run	2020-09-12 12:59:03 -07:00
Ken Hibino	450a9aa1e2	Add MaxRedirects field in RedisClusterClientOpt	2020-09-12 12:59:03 -07:00
Ken Hibino	6e294a7013	Add Username field to RedisConnOpt	2020-09-12 12:59:03 -07:00
Ken Hibino	c26b7469bd	Display cluster info in stats command when --cluster flag is passed	2020-09-12 12:59:03 -07:00
Ken Hibino	818c2d6f35	Add GetQueueName helper to extract queue name from context	2020-09-12 12:59:03 -07:00
Ken Hibino	e09870a08a	Update package documentation	2020-09-12 12:59:03 -07:00
Ken Hibino	ac3d5b126a	Update README	2020-09-12 12:59:03 -07:00
Ken Hibino	29e542e591	Rename Enqueue methods in Inspector to Run	2020-09-12 12:59:03 -07:00
Ken Hibino	a891ce5568	Rename InProgress to Active	2020-09-12 12:59:03 -07:00
Ken Hibino	ebe3c4083f	Rename NextEnqueueAt to NextProcessAt	2020-09-12 12:59:03 -07:00
Ken Hibino	c8c47fcbf0	Rename Enqueued to Pending	2020-09-12 12:59:03 -07:00
Ken Hibino	cca680a7fd	Change Client.Enqueue to take ProcessAt and ProcessIn as Option	2020-09-12 12:59:03 -07:00
Ken Hibino	8076b5ae50	Use different redis db number for rdb package tests	2020-09-12 12:59:03 -07:00
Ken Hibino	a42c174dae	Display cluster keyslot and nodes in queueList command	2020-09-12 12:59:03 -07:00
Ken Hibino	a88325cb96	Add ClusterNodes and ClusterKeySlot in Inspector	2020-09-12 12:59:03 -07:00
Ken Hibino	eb739a0258	Fix flaky test	2020-09-12 12:59:03 -07:00
Ken Hibino	a9c31553b8	Add redis-cluster support in asynq CLI	2020-09-12 12:59:03 -07:00
Ken Hibino	dab8295883	Validate queue name in Inspector	2020-09-12 12:59:03 -07:00
Ken Hibino	131ac823fd	Return error if queue name is empty when enqueueing	2020-09-12 12:59:03 -07:00
Ken Hibino	4897dba397	Upgrade redis client lib to v7.4.0	2020-09-12 12:59:03 -07:00
Ken Hibino	6b96459881	Add test flags to run tests using redis cluster	2020-09-12 12:59:03 -07:00
Ken Hibino	572eb338d5	Fix flaky ProcessorRetry test	2020-09-12 12:59:03 -07:00
Ken Hibino	27f4027447	Add RedisClusterClientOpt to connect to redis cluster	2020-09-12 12:59:03 -07:00
Ken Hibino	ee1afd12f5	Fix done lua script If UniqueKey is an empty string, do not provide the key to Lua script because that will cause CROSSSLOT error in redis cluster (since it doesn't have any hash tag).	2020-09-12 12:59:03 -07:00
Ken Hibino	3ac548e97c	Fix dequeue Lua script to use a single hash tag	2020-09-12 12:59:03 -07:00
Ken Hibino	f38f94b947	Restructure CLI commands with subcommands	2020-09-12 12:59:03 -07:00
Ken Hibino	d6f389e63f	Add Queues method to Inspector	2020-09-12 12:59:03 -07:00
Ken Hibino	118ef27bf2	Update RemoveQueue in RDB	2020-09-12 12:59:03 -07:00
Ken Hibino	fad0696828	Fix errors in inspector tests	2020-09-12 12:59:03 -07:00
Ken Hibino	4037b41479	Fix client tests	2020-09-12 12:59:03 -07:00
Ken Hibino	96f23d88cd	Add more processor tests	2020-09-12 12:59:03 -07:00
Ken Hibino	83bdca5220	Fix test build errors	2020-09-12 12:59:03 -07:00
Ken Hibino	2f226dfb84	Update ListServers and ListWorkers methods in RDB	2020-09-12 12:59:03 -07:00
Ken Hibino	3f26122ac0	Fix more build errors	2020-09-12 12:59:03 -07:00
Ken Hibino	2a18181501	Fix inspector build error	2020-09-12 12:59:03 -07:00
Ken Hibino	aa2676bb57	Update Broker interface	2020-09-12 12:59:03 -07:00
Ken Hibino	9348a62691	Update Inspector API	2020-09-12 12:59:03 -07:00
Ken Hibino	f59de9ac56	Update all delete methods in RDB	2020-09-12 12:59:03 -07:00
Ken Hibino	996a6c0ead	Update all kill methods in RDB	2020-09-12 12:59:03 -07:00
Ken Hibino	47e9ba4eba	Update enqueue methods in RDB	2020-09-12 12:59:03 -07:00
Ken Hibino	dbf140a767	Update all list methods in RDB	2020-09-12 12:59:03 -07:00
Ken Hibino	5f82b4b365	Update HistoricalStats method in RDB	2020-09-12 12:59:03 -07:00
Ken Hibino	44a3d177f0	Update Pause and Unpause methods in RDB	2020-09-12 12:59:03 -07:00
Ken Hibino	24b13bd865	Update CurrentStats method in RDB	2020-09-12 12:59:03 -07:00
Ken Hibino	d25090c669	Add AllQueues method to RDB	2020-09-12 12:59:03 -07:00
Ken Hibino	b5caefd663	Remove stale benchmark test	2020-09-12 12:59:03 -07:00
Ken Hibino	becd26479b	Update WriteServerState and ClearServerState in RDB	2020-09-12 12:59:03 -07:00
Ken Hibino	4b81b91d3e	Minor fix	2020-09-12 12:59:03 -07:00
Ken Hibino	8e23b865e9	Update recoverer	2020-09-12 12:59:03 -07:00
Ken Hibino	a873d488ee	Update ListDeadlineExceeded in RDB	2020-09-12 12:59:03 -07:00
Ken Hibino	e0a8f1252a	Update scheduler to check and enqueue for only the specified queues.	2020-09-12 12:59:03 -07:00
Ken Hibino	650d7fdbe9	Update CheckAndEnqueue method in RDB	2020-09-12 12:59:03 -07:00
Ken Hibino	f6d504939e	Update Requeue method in RDB	2020-09-12 12:59:03 -07:00
Ken Hibino	74f08795f8	Update Kill method in RDB	2020-09-12 12:59:03 -07:00
Ken Hibino	35b2b1782e	Update Retry method in RDB	2020-09-12 12:59:03 -07:00
Ken Hibino	f63dcce0c0	Update Done method in RDB	2020-09-12 12:59:03 -07:00
Ken Hibino	565f86ee4f	Update Dequeue command in rdb	2020-09-12 12:59:03 -07:00
Ken Hibino	94aa878060	Update Enqueue and Schedule commands in rdb	2020-09-12 12:59:03 -07:00
Ken Hibino	50b6034bf9	Move unique key generator function to base	2020-09-12 12:59:03 -07:00
Ken Hibino	154113d0d0	Update base package to generate redis keys with hashtag	2020-09-12 12:59:03 -07:00
Ken Hibino	669c7995c4	Run CI builds using go v1.15.x	2020-09-02 06:34:58 -07:00
Ken Hibino	6d6a301379	v0.11.0	2020-07-28 22:46:41 -07:00
Ken Hibino	53f9475582	Update changelog	2020-07-28 22:45:57 -07:00
Ken Hibino	e8fdbc5a72	Fix history command	2020-07-28 22:45:57 -07:00
Ken Hibino	5f06c308f0	Add Pause and Unpause queue methods to Inspector	2020-07-28 22:45:57 -07:00
Ken Hibino	a913e6d73f	Add healthchecker to check broker connection	2020-07-28 22:45:57 -07:00
Ken Hibino	6978e93080	Fix flaky test	2020-07-28 22:45:57 -07:00
Ken Hibino	92d77bbc6e	Minor comment fix	2020-07-28 22:45:57 -07:00
Ken Hibino	a28f61f313	Add Inspector type	2020-07-28 22:45:57 -07:00