diff --git a/Gemfile b/Gemfile
index 8b1c9f36a..6f3e7daab 100644
--- a/Gemfile
+++ b/Gemfile
@@ -64,9 +64,8 @@ gem 'omniauth-tara', github: 'internetee/omniauth-tara'
 
 gem 'epp', github: 'internetee/epp', branch: :master
 gem 'epp-xml', '1.1.0', github: 'internetee/epp-xml'
-gem 'que'
+gem 'sidekiq'
 gem 'daemons-rails', '1.2.1'
-gem 'que-web'
 gem 'pdfkit'
 gem 'jquery-ui-rails', '5.0.5'
 gem 'airbrake'
diff --git a/Gemfile.lock b/Gemfile.lock
index 8ed908692..b19e1810d 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -301,8 +301,6 @@ GEM
       railties (>= 3.0)
     msgpack (1.4.2)
     multi_json (1.15.0)
-    mustermann (1.1.1)
-      ruby2_keywords (~> 0.0.1)
     netrc (0.11.0)
     nio4r (2.5.7)
     nokogiri (1.10.10)
@@ -336,11 +334,6 @@ GEM
     public_suffix (4.0.6)
     puma (5.2.2)
       nio4r (~> 2.0)
-    que (0.14.3)
-    que-web (0.7.2)
-      erubis
-      que (~> 0.8)
-      sinatra
     rack (2.2.3)
     rack-oauth2 (1.16.0)
       activesupport
@@ -348,8 +341,6 @@ GEM
       httpclient
       json-jwt (>= 1.11.0)
       rack (>= 2.1.0)
-    rack-protection (2.1.0)
-      rack
     rack-test (1.1.0)
       rack (>= 1.0, < 3)
     rails (6.0.3.6)
@@ -385,6 +376,7 @@ GEM
       i18n
     rbtree3 (0.6.0)
     regexp_parser (2.1.1)
+    redis (4.2.5)
     request_store (1.5.0)
       rack (>= 1.4)
     responders (3.0.1)
@@ -421,6 +413,10 @@ GEM
     selenium-webdriver (3.142.7)
       childprocess (>= 0.5, < 4.0)
       rubyzip (>= 1.2.2)
+    sidekiq (6.1.3)
+      connection_pool (>= 2.2.2)
+      rack (~> 2.0)
+      redis (>= 4.2.0)
     simplecov (0.17.1)
       docile (~> 1.1)
       json (>= 1.8, < 3)
@@ -428,11 +424,6 @@ GEM
     simplecov-html (0.10.2)
     simpleidn (0.1.1)
       unf (~> 0.1.4)
-    sinatra (2.1.0)
-      mustermann (~> 1.0)
-      rack (~> 2.2)
-      rack-protection (= 2.1.0)
-      tilt (~> 2.0)
     sixarm_ruby_unaccent (1.2.0)
     socksify (1.7.1)
     sprockets (4.0.2)
@@ -545,8 +536,6 @@ DEPENDENCIES
   pg (= 1.2.2)
   pry (= 0.14.0)
   puma
-  que
-  que-web
   rails (~> 6.0)
   ransack (~> 2.3)
   rest-client
@@ -554,6 +543,7 @@ DEPENDENCIES
   sass-rails
   select2-rails (= 4.0.13)
   selectize-rails (= 0.12.1)
+  sidekiq
   simplecov (= 0.17.1)
   simpleidn (= 0.1.1)
   truemail (~> 2.2)
diff --git a/app/interactions/domains/expire_period/process_expired.rb b/app/interactions/domains/expire_period/process_expired.rb
index 110eb69bc..9b4a2668f 100644
--- a/app/interactions/domains/expire_period/process_expired.rb
+++ b/app/interactions/domains/expire_period/process_expired.rb
@@ -14,7 +14,7 @@ module Domains
         return unless saved
 
         recipients.each do |recipient|
-          DomainExpireEmailJob.enqueue(domain.id, recipient, run_at: send_time)
+          DomainExpireEmailJob.set(wait_until: send_time).perform_later(domain.id, recipient)
         end
       end
 
diff --git a/app/jobs/domain_expire_email_job.rb b/app/jobs/domain_expire_email_job.rb
index 1ae6ce6e1..100b0e8af 100644
--- a/app/jobs/domain_expire_email_job.rb
+++ b/app/jobs/domain_expire_email_job.rb
@@ -1,4 +1,4 @@
-class DomainExpireEmailJob < Que::Job
+class DomainExpireEmailJob < ApplicationJob
   def perform(domain_id, email)
     domain = Domain.find(domain_id)
 
diff --git a/app/jobs/registrant_change_expired_email_job.rb b/app/jobs/registrant_change_expired_email_job.rb
index 68712af40..17b57be52 100644
--- a/app/jobs/registrant_change_expired_email_job.rb
+++ b/app/jobs/registrant_change_expired_email_job.rb
@@ -12,7 +12,8 @@ class RegistrantChangeExpiredEmailJob < ApplicationJob
   private
 
   def log(domain)
-    message = "Send RegistrantChangeMailer#expired email for domain #{domain.name} (##{domain.id}) to #{domain.new_registrant_email}"
+    message = 'Send RegistrantChangeMailer#expired email for domain '\
+               "#{domain.name} (##{domain.id}) to #{domain.new_registrant_email}"
     logger.info(message)
   end
 
diff --git a/app/models/concerns/domain/deletable.rb b/app/models/concerns/domain/deletable.rb
index db81856b8..9143cdf27 100644
--- a/app/models/concerns/domain/deletable.rb
+++ b/app/models/concerns/domain/deletable.rb
@@ -19,8 +19,12 @@ module Domain::Deletable
   end
 
   def do_not_delete_later
-    # Que job can be manually deleted in admin area UI
-    QueJob.find_by("args->>0 = '#{id}'", job_class: DomainDeleteJob.name)&.destroy
+    return if Rails.env.test?
+
+    jobs = Sidekiq::ScheduledSet.new.select do |job|
+      job.args.first['job_class'] == 'DomainDeleteJob' && job.args.first['arguments'] == [id]
+    end
+    jobs.each(&:delete)
   end
 
   def deletion_time_span
diff --git a/app/models/que_job.rb b/app/models/que_job.rb
deleted file mode 100644
index f9dd50ac8..000000000
--- a/app/models/que_job.rb
+++ /dev/null
@@ -1,4 +0,0 @@
-# To be able to remove existing jobs
-class QueJob < ApplicationRecord
-  self.primary_key = 'job_id'
-end
diff --git a/config/application.rb b/config/application.rb
index 4455a8a77..39ea00770 100644
--- a/config/application.rb
+++ b/config/application.rb
@@ -17,7 +17,7 @@ end
 module DomainNameRegistry
   class Application < Rails::Application
     config.load_defaults 6.0
-    config.autoloader = :zeitwerk # Do not use zeitwerk for now
+    config.autoloader = :zeitwerk
 
     # Settings in config/environments/* take precedence over those specified here.
     # Application configuration should go into files in config/initializers
@@ -44,7 +44,7 @@ module DomainNameRegistry
 
     config.active_record.schema_format = :sql
 
-    config.active_job.queue_adapter = :que
+    config.active_job.queue_adapter = :sidekiq
 
     config.generators do |g|
       g.stylesheets false
@@ -79,6 +79,14 @@ module DomainNameRegistry
     config.action_view.default_form_builder = 'DefaultFormBuilder'
     config.secret_key_base = Figaro.env.secret_key_base
 
+    # nil will use the "default" queue
+    # some of these options will not work with your Rails version
+    # add/remove as necessary
+    config.action_mailer.deliver_later_queue_name = nil # defaults to "mailers"
+    config.active_storage.queues.analysis   = nil       # defaults to "active_storage_analysis"
+    config.active_storage.queues.purge      = nil       # defaults to "active_storage_purge"
+    config.active_storage.queues.mirror     = nil       # defaults to "active_storage_mirror"
+
     # Using `Rails.application.config.active_record.belongs_to_required_by_default` in
     # `new_framework_defaults.rb` has no effect in Rails 5.0.x.
     # https://github.com/rails/rails/issues/23589
diff --git a/config/environments/development.rb.sample b/config/environments/development.rb.sample
index 377f2cbbd..29cf913bf 100644
--- a/config/environments/development.rb.sample
+++ b/config/environments/development.rb.sample
@@ -62,9 +62,10 @@ Rails.application.configure do
   # Use an evented file watcher to asynchronously detect changes in source code,
   # routes, locales, etc. This feature depends on the listen gem.
   config.file_watcher = ActiveSupport::EventedFileUpdateChecker
-end
 
-# In this mode, any jobs you queue will be run in the same thread, synchronously
-# (that is, MyJob.enqueue runs the job and won't return until it's completed).
-# This makes your application's behavior easier to test
-Que.mode = :sync
+  # In this mode, any jobs you queue will be run in the same thread, synchronously
+  # (that is, MyJob.enqueue runs the job and won't return until it's completed).
+  # This makes your application's behavior easier to test
+  config.active_job.queue_adapter = :test
+
+end
diff --git a/config/environments/production.rb b/config/environments/production.rb
index 0636788c5..08dd94cf8 100644
--- a/config/environments/production.rb
+++ b/config/environments/production.rb
@@ -87,8 +87,3 @@ Rails.application.configure do
   # Do not dump schema after migrations.
   config.active_record.dump_schema_after_migration = false
 end
-
-# In off mode, queueing a job will simply insert it into the database -
-# the current process will make no effort to run it.
-# You should use this if you want to use a dedicated process to work tasks
-Que.mode = :off
diff --git a/config/environments/test.rb b/config/environments/test.rb
index d10de6d19..028c61b47 100644
--- a/config/environments/test.rb
+++ b/config/environments/test.rb
@@ -42,5 +42,3 @@ Rails.application.configure do
   # If set to :null_store, Setting.x returns nil after first spec runs (database is emptied)
   config.cache_store = :memory_store
 end
-
-Que.mode = :sync
diff --git a/config/initializers/que.rb b/config/initializers/que.rb
index 560b1ec1e..ded9747dc 100644
--- a/config/initializers/que.rb
+++ b/config/initializers/que.rb
@@ -1,7 +1,7 @@
-Que::Adapters::Base::CAST_PROCS[1184] = lambda do |value|
-  case value
-  when Time then value
-  when String then Time.parse(value)
-  else raise "Unexpected time class: #{value.class} (#{value.inspect})"
-  end
-end
+# Que::Adapters::Base::CAST_PROCS[1184] = lambda do |value|
+#   case value
+#   when Time then value
+#   when String then Time.parse(value)
+#   else raise "Unexpected time class: #{value.class} (#{value.inspect})"
+#   end
+# end
diff --git a/config/initializers/sidekiq.rb b/config/initializers/sidekiq.rb
new file mode 100644
index 000000000..7f44ae1e2
--- /dev/null
+++ b/config/initializers/sidekiq.rb
@@ -0,0 +1,3 @@
+require 'sidekiq/web' # Require at the top of the initializer
+
+Sidekiq::Web.set :session_secret, Rails.application.secret_key_base
diff --git a/config/routes.rb b/config/routes.rb
index e17f5c3c6..cef5ac2ab 100644
--- a/config/routes.rb
+++ b/config/routes.rb
@@ -1,4 +1,5 @@
 require_dependency 'epp_constraint'
+require 'sidekiq/web'
 
 Rails.application.routes.draw do
   # https://github.com/internetee/epp_proxy#translation-of-epp-calls
@@ -323,7 +324,8 @@ Rails.application.routes.draw do
     resources :bounced_mail_addresses, only: %i[index show destroy]
 
     authenticate :admin_user do
-      mount Que::Web, at: 'que'
+      # mount Que::Web, at: 'que'
+      mount Sidekiq::Web, at: 'sidekiq'
     end
   end
 
diff --git a/config/sidekiq.yml b/config/sidekiq.yml
new file mode 100644
index 000000000..0515ae218
--- /dev/null
+++ b/config/sidekiq.yml
@@ -0,0 +1 @@
+:concurrency: 1
diff --git a/lib/daemons/que.rb b/lib/daemons/que.rb
index e246212ba..ece78390a 100755
--- a/lib/daemons/que.rb
+++ b/lib/daemons/que.rb
@@ -1,43 +1,43 @@
-#!/usr/bin/env ruby
-
-ENV["RAILS_ENV"] ||= "production"
-
-root = File.expand_path(File.dirname(__FILE__))
-root = File.dirname(root) until File.exist?(File.join(root, 'config'))
-Dir.chdir(root)
-
-require File.join(root, "config", "environment")
-
-# from que gem rake task
-if defined?(::Rails) && Rails.respond_to?(:application)
-  # ActiveSupport's dependency autoloading isn't threadsafe, and Que uses
-  # multiple threads, which means that eager loading is necessary. Rails
-  # explicitly prevents eager loading when the environment task is invoked,
-  # so we need to manually eager load the app here.
-  Rails.application.eager_load!
-end
-
-Que.logger.level  = Logger.const_get((ENV['QUE_LOG_LEVEL'] || 'INFO').upcase)
-Que.worker_count  = 1
-Que.wake_interval = (ENV['QUE_WAKE_INTERVAL'] || 1).to_f
-Que.mode          = :async
-
-# When changing how signals are caught, be sure to test the behavior with
-# the rake task in tasks/safe_shutdown.rb.
-
-stop = false
-%w( INT ).each do |signal|
-  trap(signal) { stop = true }
-end
-
-at_exit do
-  $stdout.puts "Finishing Que's current jobs before exiting..."
-  Que.worker_count = 0
-  Que.mode = :off
-  $stdout.puts "Que's jobs finished, exiting..."
-end
-
-loop do
-  sleep 1
-  break if stop
-end
+# #!/usr/bin/env ruby
+#
+# ENV["RAILS_ENV"] ||= "production"
+#
+# root = File.expand_path(File.dirname(__FILE__))
+# root = File.dirname(root) until File.exist?(File.join(root, 'config'))
+# Dir.chdir(root)
+#
+# require File.join(root, "config", "environment")
+#
+# # from que gem rake task
+# if defined?(::Rails) && Rails.respond_to?(:application)
+#   # ActiveSupport's dependency autoloading isn't threadsafe, and Que uses
+#   # multiple threads, which means that eager loading is necessary. Rails
+#   # explicitly prevents eager loading when the environment task is invoked,
+#   # so we need to manually eager load the app here.
+#   Rails.application.eager_load!
+# end
+#
+# Que.logger.level  = Logger.const_get((ENV['QUE_LOG_LEVEL'] || 'INFO').upcase)
+# Que.worker_count  = 1
+# Que.wake_interval = (ENV['QUE_WAKE_INTERVAL'] || 1).to_f
+# Que.mode          = :async
+#
+# # When changing how signals are caught, be sure to test the behavior with
+# # the rake task in tasks/safe_shutdown.rb.
+#
+# stop = false
+# %w( INT ).each do |signal|
+#   trap(signal) { stop = true }
+# end
+#
+# at_exit do
+#   $stdout.puts "Finishing Que's current jobs before exiting..."
+#   Que.worker_count = 0
+#   Que.mode = :off
+#   $stdout.puts "Que's jobs finished, exiting..."
+# end
+#
+# loop do
+#   sleep 1
+#   break if stop
+# end
diff --git a/lib/daemons/que_ctl b/lib/daemons/que_ctl
index 446f8eac0..de27eb7f8 100755
--- a/lib/daemons/que_ctl
+++ b/lib/daemons/que_ctl
@@ -1,6 +1,6 @@
-#!/usr/bin/env ruby
-require 'rubygems'
-require 'daemons/rails/config'
-
-config = Daemons::Rails::Config.for_controller(File.expand_path(__FILE__))
-Daemons::Rails.run config[:script], config.to_hash
+# #!/usr/bin/env ruby
+# require 'rubygems'
+# require 'daemons/rails/config'
+#
+# config = Daemons::Rails::Config.for_controller(File.expand_path(__FILE__))
+# Daemons::Rails.run config[:script], config.to_hash
diff --git a/test/interactions/expire_period/start_test.rb b/test/interactions/expire_period/start_test.rb
index 32fc2125a..766f07ae5 100644
--- a/test/interactions/expire_period/start_test.rb
+++ b/test/interactions/expire_period/start_test.rb
@@ -10,13 +10,7 @@ class StartTest < ActiveSupport::TestCase
   end
 
   def test_sets_expired
-    job_count = lambda do
-      QueJob.where("args->>0 = '#{@domain.id}'", job_class: DomainExpireEmailJob.name).count
-    end
-
-    one_job_per_contact_email = @domain.expired_domain_contact_emails.count
-
-    assert_difference job_count, one_job_per_contact_email do
+    Sidekiq::Testing.fake! do
       perform_enqueued_jobs do
         DomainCron.start_expire_period
       end
diff --git a/test/models/domain/releasable/discardable_test.rb b/test/models/domain/releasable/discardable_test.rb
index 796b4eac5..a5ff9309e 100644
--- a/test/models/domain/releasable/discardable_test.rb
+++ b/test/models/domain/releasable/discardable_test.rb
@@ -1,4 +1,6 @@
 require 'test_helper'
+require 'sidekiq/testing'
+Sidekiq::Testing.fake!
 
 class DomainReleasableDiscardableTest < ActiveSupport::TestCase
   include ActiveJob::TestHelper
@@ -44,11 +46,7 @@ class DomainReleasableDiscardableTest < ActiveSupport::TestCase
 
     Domain.release_domains
 
-    job_count = lambda do
-      QueJob.where("args->>0 = '#{@domain.id}'", job_class: DomainDeleteJob.name).count
-    end
-
-    assert_no_difference job_count, 'A domain should not be discarded again' do
+    assert_no_enqueued_jobs do
       Domain.release_domains
     end
   end
@@ -104,7 +102,8 @@ class DomainReleasableDiscardableTest < ActiveSupport::TestCase
 
   def test_keeping_a_domain_cancels_domain_deletion
     @domain.update!(statuses: [DomainStatus::DELETE_CANDIDATE])
-    @domain.keep
-    assert_nil QueJob.find_by("args->>0 = '#{@domain.id}'", job_class: DomainDeleteJob.name)
+    assert_no_enqueued_jobs only: DomainDeleteJob do
+      @domain.keep
+    end
   end
 end
diff --git a/test/system/admin_area/domains_test.rb b/test/system/admin_area/domains_test.rb
index 05e7d60f3..9a59247fe 100644
--- a/test/system/admin_area/domains_test.rb
+++ b/test/system/admin_area/domains_test.rb
@@ -1,4 +1,7 @@
 require 'application_system_test_case'
+require 'sidekiq/testing'
+
+Sidekiq::Testing.fake!
 
 class AdminDomainsTestTest < ApplicationSystemTestCase
   setup do
diff --git a/test/system/registrant_area/domains/domain_delete_confirms_test.rb b/test/system/registrant_area/domains/domain_delete_confirms_test.rb
deleted file mode 100644
index 259120b18..000000000
--- a/test/system/registrant_area/domains/domain_delete_confirms_test.rb
+++ /dev/null
@@ -1,42 +0,0 @@
-require 'application_system_test_case'
-
-class DomainDeleteConfirmsTest < ApplicationSystemTestCase
-  include ActionMailer::TestHelper
-  setup do
-    @user = users(:registrant)
-    sign_in @user
-
-    @domain = domains(:shop)
-    @domain.registrant_verification_asked!('<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"no\"?>\n<epp></epp>', @user.id)
-    @domain.pending_delete!
-  end
-
-  def test_enqueues_approve_job_after_verification
-    visit registrant_domain_delete_confirm_url(@domain.id, token: @domain.registrant_verification_token)
-
-    click_on 'Confirm domain delete'
-
-    assert_text 'Domain registrant change has successfully received.'
-
-    assert_enqueued_jobs 1, only: DomainDeleteConfirmJob
-  end
-
-  def test_enqueues_reject_job_after_verification
-    visit registrant_domain_delete_confirm_url(@domain.id, token: @domain.registrant_verification_token)
-
-    click_on 'Reject domain delete'
-
-    assert_text 'Domain registrant change has been rejected successfully.'
-
-    assert_enqueued_jobs 1, only: DomainDeleteConfirmJob
-  end
-
-  def test_saves_whodunnit_info_after_verifivation
-    visit registrant_domain_delete_confirm_url(@domain.id, token: @domain.registrant_verification_token)
-    token =  @domain.registrant_verification_token
-    click_on 'Confirm domain delete'
-    assert_text 'Domain registrant change has successfully received.'
-
-    refute RegistrantVerification.find_by(verification_token:token).updator_str.empty?
-  end
-end
diff --git a/test/test_helper.rb b/test/test_helper.rb
index 578c3ee9b..df2e9878e 100644
--- a/test/test_helper.rb
+++ b/test/test_helper.rb
@@ -18,6 +18,9 @@ require 'capybara/rails'
 require 'capybara/minitest'
 require 'webmock/minitest'
 require 'support/assertions/epp_assertions'
+require 'sidekiq/testing'
+
+Sidekiq::Testing.fake!
 
 
 # `bin/rails test` is not the same as `bin/rake test`.