From 28af97c6b48b76738757799a1a2aac85b63ae8fa Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Fri, 5 Dec 2025 12:40:54 +0000
Subject: [PATCH 1/5] Initial plan


From 1ef9b049152d65f12cafb7d209effa06901fc34d Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Fri, 5 Dec 2025 12:48:04 +0000
Subject: [PATCH 2/5] Migrate ActiveJob adapter from delayed_job to sidekiq

- Replace delayed_job_active_record with sidekiq and redis gems
- Update ActiveJob queue adapter configuration
- Create sidekiq initializer with Redis and queue configuration
- Replace lib/seek/workers.rb to manage Sidekiq processes
- Update queue_names.rb to remove Delayed::Worker dependency
- Update admin controller to work with Sidekiq workers
- Update Seek::Util helper methods for Sidekiq
- Add Redis service to docker-compose.yml
- Update docker worker startup script to tail sidekiq.log
- Remove delayed_job_config.rb initializer

Co-authored-by: fbacall <503373+fbacall@users.noreply.github.com>
---
 Gemfile                                   |  4 +-
 app/controllers/admin_controller.rb       |  5 +-
 app/jobs/queue_names.rb                   |  2 +-
 config/application.rb                     |  2 +-
 config/initializers/delayed_job_config.rb | 23 -------
 config/initializers/sidekiq.rb            | 36 +++++++++++
 config/sidekiq.yml                        | 14 +++++
 docker-compose.yml                        | 14 ++++-
 docker/start_workers.sh                   |  4 +-
 lib/seek/util.rb                          | 11 ++--
 lib/seek/workers.rb                       | 75 ++++++++++++++++-------
 11 files changed, 128 insertions(+), 62 deletions(-)
 delete mode 100644 config/initializers/delayed_job_config.rb
 create mode 100644 config/initializers/sidekiq.rb
 create mode 100644 config/sidekiq.yml

diff --git a/Gemfile b/Gemfile
index 7c4250d7d2..eeacc08efd 100644
--- a/Gemfile
+++ b/Gemfile
@@ -27,8 +27,8 @@ gem 'commonmarker'
 gem 'country_select'
 gem 'csl-styles'
 gem 'csv'
-gem 'daemons'
-gem 'delayed_job_active_record'
+gem 'redis', '~> 5.0'
+gem 'sidekiq', '~> 7.0'
 gem 'docsplit', git: 'https://github.com/documentcloud/docsplit.git'
 gem 'doorkeeper'
 gem 'dotenv-rails'
diff --git a/app/controllers/admin_controller.rb b/app/controllers/admin_controller.rb
index 42cf82ea97..2d2058921c 100644
--- a/app/controllers/admin_controller.rb
+++ b/app/controllers/admin_controller.rb
@@ -1,5 +1,3 @@
-require 'delayed/command'
-
 class AdminController < ApplicationController
   include CommonSweepers
 
@@ -381,9 +379,8 @@ def clear_cache
   # give it up to 5 seconds to start up, otherwise the page reloads too quickly and says it is not running
   def wait_for_delayed_job_to_start
     sleep(0.5)
-    pid = Daemons::PidFile.new("#{Rails.root}/tmp/pids", 'delayed_job.0')
     count = 0
-    while !pid.running? && (count < 10)
+    while !Seek::Workers.running? && (count < 10)
       sleep(0.5)
       count += 1
     end
diff --git a/app/jobs/queue_names.rb b/app/jobs/queue_names.rb
index 1da5f863db..3efa02b573 100644
--- a/app/jobs/queue_names.rb
+++ b/app/jobs/queue_names.rb
@@ -3,7 +3,7 @@ class QueueNames
   DATAFILES = 'datafiles'.freeze
   REMOTE_CONTENT = 'remotecontent'.freeze
   AUTH_LOOKUP = 'authlookup'.freeze
-  DEFAULT = Delayed::Worker.default_queue_name
+  DEFAULT = 'default'.freeze
   MAILERS = SEEK::Application.config.action_mailer.deliver_later_queue_name
   INDEXING = 'indexing'.freeze
   TEMPLATES = 'templates'.freeze
diff --git a/config/application.rb b/config/application.rb
index 72a7a13617..5b3f59b160 100644
--- a/config/application.rb
+++ b/config/application.rb
@@ -75,7 +75,7 @@ class Application < Rails::Application
 
     config.action_mailer.deliver_later_queue_name = 'mailers'
 
-    config.active_job.queue_adapter = :delayed_job
+    config.active_job.queue_adapter = :sidekiq
 
     # Revert Rails 7 change that auto loads nested locale files
     initializer :avoid_nested_locale_directories, before: :add_locales do
diff --git a/config/initializers/delayed_job_config.rb b/config/initializers/delayed_job_config.rb
deleted file mode 100644
index 52de0b551e..0000000000
--- a/config/initializers/delayed_job_config.rb
+++ /dev/null
@@ -1,23 +0,0 @@
-# Try and avoid deadlocks
-Delayed::Backend::ActiveRecord.configure do |config|
-  config.reserve_sql_strategy = :default_sql
-end
-
-SEEK::Application.configure do
-
-  Delayed::Worker.destroy_failed_jobs = false
-  if Rails.env.development?
-    Delayed::Worker.sleep_delay = 45
-  else
-    Delayed::Worker.sleep_delay = 3
-  end
-
-  Delayed::Worker.max_attempts = 1
-  Delayed::Worker.max_run_time = 1.day
-  Delayed::Worker.read_ahead = 20
-  Delayed::Worker.backend = :active_record
-  Delayed::Worker.default_queue_name = 'default'
-
-  #Delayed::Worker.logger = Delayed::Worker.logger = ActiveSupport::BufferedLogger.new(Rails.root.join('log/worker.log'),Logger::INFO)
-  #Delayed::Worker.logger.auto_flushing = 1
-end
diff --git a/config/initializers/sidekiq.rb b/config/initializers/sidekiq.rb
new file mode 100644
index 0000000000..f10e0a1887
--- /dev/null
+++ b/config/initializers/sidekiq.rb
@@ -0,0 +1,36 @@
+# Sidekiq configuration
+Sidekiq.configure_server do |config|
+  config.redis = { url: ENV.fetch('REDIS_URL', 'redis://localhost:6379/0') }
+  
+  # Configure concurrency
+  config.concurrency = ENV.fetch('SIDEKIQ_CONCURRENCY', 5).to_i
+  
+  # Set default error handler
+  config.error_handlers << lambda { |exception, context|
+    Rails.logger.error("Sidekiq error: #{exception.message}")
+    Rails.logger.error(exception.backtrace.join("\n"))
+  }
+end
+
+Sidekiq.configure_client do |config|
+  config.redis = { url: ENV.fetch('REDIS_URL', 'redis://localhost:6379/0') }
+end
+
+# Configure default Sidekiq options
+Sidekiq.default_job_options = {
+  'backtrace' => true,
+  'retry' => false  # Match the delayed_job behavior where max_attempts was 1
+}
+
+# Map queue names to priorities
+# Higher weight = higher priority
+Sidekiq.options[:queues] = [
+  ['default', 2],
+  ['mailers', 2],
+  ['authlookup', 2],
+  ['remotecontent', 2],
+  ['samples', 2],
+  ['indexing', 2],
+  ['templates', 2],
+  ['datafiles', 2]
+]
diff --git a/config/sidekiq.yml b/config/sidekiq.yml
new file mode 100644
index 0000000000..4decf185b4
--- /dev/null
+++ b/config/sidekiq.yml
@@ -0,0 +1,14 @@
+---
+:concurrency: 5
+:max_retries: 0
+:timeout: 86400
+
+:queues:
+  - default
+  - mailers
+  - authlookup
+  - remotecontent
+  - samples
+  - indexing
+  - templates
+  - datafiles
diff --git a/docker-compose.yml b/docker-compose.yml
index 169fb2c8b8..d17163cd85 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -8,6 +8,7 @@ x-shared:
       RAILS_ENV: production
       SOLR_PORT: 8983
       SOLR_HOST: solr
+      REDIS_URL: redis://redis:6379/0
       RAILS_LOG_LEVEL: info # debug, info, warn, error or fatal
     env_file:
       - docker/db.env
@@ -19,6 +20,8 @@ x-shared:
         condition: service_healthy
       solr:
         condition: service_started
+      redis:
+        condition: service_started
 
 
 services:
@@ -59,7 +62,7 @@ services:
       start_period: 20s
 
   seek_workers:
-    # The SEEK delayed job workers
+    # The SEEK background job workers (Sidekiq)
     <<: *seek_base
     container_name: seek-workers
     environment:
@@ -81,6 +84,13 @@ services:
       - seek
       - /opt/solr/server/solr/configsets/seek_config
 
+  redis:
+    image: redis:7-alpine
+    container_name: seek-redis
+    restart: always
+    volumes:
+      - seek-redis-data:/data
+
 volumes:
   seek-filestore:
     external: true
@@ -88,5 +98,7 @@ volumes:
     external: true
   seek-solr-data:
     external: true
+  seek-redis-data:
+    external: true
   seek-cache:
     external: true
diff --git a/docker/start_workers.sh b/docker/start_workers.sh
index 42e7f1e005..d664eea768 100644
--- a/docker/start_workers.sh
+++ b/docker/start_workers.sh
@@ -17,9 +17,9 @@ echo "STARTING WORKERS"
 bundle exec rake seek:workers:start
 
 # Ensure the workers have started up and the logs are available before tailing
-while [ ! -f log/production.log ]
+while [ ! -f log/sidekiq.log ]
 do
   sleep 0.2
 done
 
-tail -f log/production.log
+tail -f log/sidekiq.log
diff --git a/lib/seek/util.rb b/lib/seek/util.rb
index 749c91b294..8ccb62e6bc 100644
--- a/lib/seek/util.rb
+++ b/lib/seek/util.rb
@@ -140,12 +140,13 @@ def self.database_type
       ActiveRecord::Base.connection.instance_values['config'][:adapter]
     end
 
+    def self.background_job_pids
+      Seek::Workers.pids
+    end
+
+    # Alias for backwards compatibility
     def self.delayed_job_pids
-      directory = "#{Rails.root}/tmp/pids"
-      Daemons::PidFile.find_files(directory, 'delayed_job', false, '').collect do |path|
-        file = path.sub("#{directory}/", '').sub('.pid', '')
-        Daemons::PidFile.new(directory, file)
-      end
+      background_job_pids
     end
 
     # Use this to avoid needlessly regenerating the url helper module each time a route needs to be accessed
diff --git a/lib/seek/workers.rb b/lib/seek/workers.rb
index 354f78a792..c10037c741 100644
--- a/lib/seek/workers.rb
+++ b/lib/seek/workers.rb
@@ -1,24 +1,18 @@
-require 'delayed/command'
-
-# module for handling interaction with delayed job workers
+# module for handling interaction with Sidekiq workers
 module Seek
   module Workers
+    SIDEKIQ_PID_FILE = "#{Rails.root}/tmp/pids/sidekiq.pid".freeze
+    
     def self.start
-      commands = create_commands('start')
-      daemonize_commands(commands)
-    end
-
-    def self.daemonize_commands(commands)
-      commands.map { |command| Delayed::Command.new(command.split).daemonize }
-    end
-
-    def self.create_commands(action)
-      commands = []
-
-      active_queues.each_with_index do |queue_name, index|
-        commands << command(queue_name, index + 1, 1, action)
-      end
-      commands
+      return if running?
+      
+      queues = active_queues.join(',')
+      command = "bundle exec sidekiq -d -e #{Rails.env} " \
+                "-C config/sidekiq.yml " \
+                "-P #{SIDEKIQ_PID_FILE} " \
+                "-L #{Rails.root}/log/sidekiq.log"
+      
+      system(command)
     end
 
     def self.active_queues
@@ -34,21 +28,56 @@ def self.active_queues
     end
 
     def self.stop
-      # will stop the first 15, not expecting more than that
-      daemonize_commands(['stop -n 15'])
+      if File.exist?(SIDEKIQ_PID_FILE)
+        pid = File.read(SIDEKIQ_PID_FILE).to_i
+        begin
+          Process.kill('TERM', pid)
+          # Wait for graceful shutdown
+          10.times do
+            sleep(1)
+            break unless process_running?(pid)
+          end
+          # Force kill if still running
+          Process.kill('KILL', pid) if process_running?(pid)
+        rescue Errno::ESRCH
+          # Process doesn't exist
+        end
+        File.delete(SIDEKIQ_PID_FILE) if File.exist?(SIDEKIQ_PID_FILE)
+      end
     end
 
     def self.status
-      daemonize_commands(['status'])
+      if running?
+        puts "Sidekiq is running (PID: #{File.read(SIDEKIQ_PID_FILE).strip})"
+      else
+        puts "Sidekiq is not running"
+      end
     end
 
     def self.restart
       stop
+      sleep(1)
       start
     end
 
-    def self.command(queue_name, index, number_of_workers, action)
-      "--queue=#{queue_name} -i #{index} -n #{number_of_workers} #{action}"
+    def self.running?
+      if File.exist?(SIDEKIQ_PID_FILE)
+        pid = File.read(SIDEKIQ_PID_FILE).to_i
+        process_running?(pid)
+      else
+        false
+      end
+    end
+
+    def self.process_running?(pid)
+      Process.kill(0, pid)
+      true
+    rescue Errno::ESRCH, Errno::EPERM
+      false
+    end
+
+    def self.pids
+      running? ? [File.read(SIDEKIQ_PID_FILE).to_i] : []
     end
   end
 end

From 34e57d251a34572e9da35a6486d1ba8ac968b268 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Fri, 5 Dec 2025 12:50:39 +0000
Subject: [PATCH 3/5] Update tests and remaining references from delayed_job to
 sidekiq

- Update admin controller tests to reference background job workers
- Update clear_failed_jobs to use Sidekiq API instead of ActiveRecord
- Remove obsolete delayed_jobs table check from seek_main.rb
- Add Redis service to docker-compose-virtuoso.yml
- Add Redis service to docker-compose-relative-root.yml

Co-authored-by: fbacall <503373+fbacall@users.noreply.github.com>
---
 app/controllers/admin_controller.rb      |  7 +++++--
 config/initializers/seek_main.rb         |  9 ---------
 docker-compose-relative-root.yml         | 14 +++++++++++++-
 docker-compose-virtuoso.yml              | 13 ++++++++++++-
 test/functional/admin_controller_test.rb |  4 ++--
 5 files changed, 32 insertions(+), 15 deletions(-)

diff --git a/app/controllers/admin_controller.rb b/app/controllers/admin_controller.rb
index 2d2058921c..e9c5c2d1c0 100644
--- a/app/controllers/admin_controller.rb
+++ b/app/controllers/admin_controller.rb
@@ -610,9 +610,12 @@ def array_remove_at(array, index)
     return array.slice(0,index) + array.slice(index+1,array.length)
   end
 
-  # this destroys any failed Delayed::Jobs
+  # this destroys any failed jobs
   def clear_failed_jobs
-    Delayed::Job.where('failed_at IS NOT NULL').destroy_all
+    # Clear Sidekiq dead jobs
+    require 'sidekiq/api'
+    Sidekiq::DeadSet.new.clear
+    Sidekiq::RetrySet.new.clear
     respond_to do |format|
       format.json { head :ok }
     end
diff --git a/config/initializers/seek_main.rb b/config/initializers/seek_main.rb
index 858b49d4cf..1d06666e31 100644
--- a/config/initializers/seek_main.rb
+++ b/config/initializers/seek_main.rb
@@ -44,14 +44,5 @@
     Annotations::Config.versioning_enabled = false
 
     ENV['LANG'] = 'en_US.UTF-8'
-
-    begin
-      if ActiveRecord::Base.connection.data_source_exists?'delayed_jobs'
-        # OpenbisFakeJob.create_initial_jobs
-        # OpenbisGarbageJob.create_initial_jobs
-      end
-    rescue Exception=>e
-      Rails.logger.error "Error creating default delayed jobs - #{e.message}"
-    end
   end
 end
diff --git a/docker-compose-relative-root.yml b/docker-compose-relative-root.yml
index 809bd76191..cccd6dfff3 100644
--- a/docker-compose-relative-root.yml
+++ b/docker-compose-relative-root.yml
@@ -8,6 +8,7 @@ x-shared:
       RAILS_ENV: production
       SOLR_PORT: 8983
       SOLR_HOST: solr
+      REDIS_URL: redis://redis:6379/0
       RAILS_LOG_LEVEL: info # debug, info, warn, error or fatal
       RAILS_RELATIVE_URL_ROOT: '/seek'
     env_file:
@@ -20,6 +21,8 @@ x-shared:
         condition: service_healthy
       solr:
         condition: service_started
+      redis:
+        condition: service_started
 
 
 services:
@@ -60,7 +63,7 @@ services:
       start_period: 20s
 
   seek_workers:
-    # The SEEK delayed job workers
+    # The SEEK background job workers (Sidekiq)
     <<: *seek_base
     container_name: seek-workers
     environment:
@@ -82,6 +85,13 @@ services:
       - seek
       - /opt/solr/server/solr/configsets/seek_config      
 
+  redis:
+    image: redis:7-alpine
+    container_name: seek-redis
+    restart: always
+    volumes:
+      - seek-redis-data:/data
+
 
 volumes:
   seek-filestore:
@@ -90,6 +100,8 @@ volumes:
     external: true
   seek-solr-data:
     external: true
+  seek-redis-data:
+    external: true
   seek-cache:
     external: true
   seek-assets:
diff --git a/docker-compose-virtuoso.yml b/docker-compose-virtuoso.yml
index d6e19a002d..8ff2641f3e 100644
--- a/docker-compose-virtuoso.yml
+++ b/docker-compose-virtuoso.yml
@@ -8,6 +8,7 @@ x-shared:
       RAILS_ENV: production
       SOLR_PORT: 8983
       SOLR_HOST: solr
+      REDIS_URL: redis://redis:6379/0
       RAILS_LOG_LEVEL: info # debug, info, warn, error or fatal
     env_file:
       - docker/db.env
@@ -20,6 +21,8 @@ x-shared:
         condition: service_healthy
       solr:
         condition: service_started
+      redis:
+        condition: service_started
       virtuoso:
         condition: service_started
 
@@ -60,7 +63,7 @@ services:
       start_period: 20s
 
   seek_workers:
-    # The SEEK delayed job workers
+    # The SEEK background job workers (Sidekiq)
     <<: *seek_base
     container_name: seek-workers
     environment:
@@ -94,10 +97,18 @@ services:
     volumes:
       - seek-virtuoso-data:/database
 
+  redis:
+    image: redis:7-alpine
+    container_name: seek-redis
+    restart: always
+    volumes:
+      - seek-redis-data:/data
+
 
 volumes:
   seek-filestore:
   seek-mysql-db:
   seek-solr-data:
+  seek-redis-data:
   seek-cache:
   seek-virtuoso-data:
diff --git a/test/functional/admin_controller_test.rb b/test/functional/admin_controller_test.rb
index f342837174..61e4f34c05 100644
--- a/test/functional/admin_controller_test.rb
+++ b/test/functional/admin_controller_test.rb
@@ -30,13 +30,13 @@ def setup
     assert_response :success
   end
 
-  test 'non admin cannot restart the delayed job' do
+  test 'non admin cannot restart the background job workers' do
     login_as(FactoryBot.create(:user))
     post :restart_delayed_job
     refute_nil flash[:error]
   end
 
-  test 'admin can restart the delayed job' do
+  test 'admin can restart the background job workers' do
     post :restart_delayed_job
     assert_nil flash[:error]
   end

From 123ce4b5123191d355349f3303035252cc0fc6c6 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Fri, 5 Dec 2025 12:52:12 +0000
Subject: [PATCH 4/5] Address code review feedback

- Add Errno::EINVAL to exception handling in process_running?
- Extract PID file reading logic into private method to reduce duplication
- Add comment explaining 24-hour timeout value in sidekiq.yml
- Add comment explaining equal queue weights in sidekiq initializer

Co-authored-by: fbacall <503373+fbacall@users.noreply.github.com>
---
 config/initializers/sidekiq.rb |  3 ++-
 config/sidekiq.yml             |  1 +
 lib/seek/workers.rb            | 14 ++++++++++----
 3 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/config/initializers/sidekiq.rb b/config/initializers/sidekiq.rb
index f10e0a1887..6313409062 100644
--- a/config/initializers/sidekiq.rb
+++ b/config/initializers/sidekiq.rb
@@ -23,7 +23,8 @@
 }
 
 # Map queue names to priorities
-# Higher weight = higher priority
+# All queues have equal weight (2) as jobs are prioritized by the queue they're placed in
+# rather than by priority weighting within Sidekiq
 Sidekiq.options[:queues] = [
   ['default', 2],
   ['mailers', 2],
diff --git a/config/sidekiq.yml b/config/sidekiq.yml
index 4decf185b4..3464be5809 100644
--- a/config/sidekiq.yml
+++ b/config/sidekiq.yml
@@ -1,6 +1,7 @@
 ---
 :concurrency: 5
 :max_retries: 0
+# Timeout for job execution (24 hours) - matches previous delayed_job max_run_time
 :timeout: 86400
 
 :queues:
diff --git a/lib/seek/workers.rb b/lib/seek/workers.rb
index c10037c741..1363033443 100644
--- a/lib/seek/workers.rb
+++ b/lib/seek/workers.rb
@@ -29,7 +29,7 @@ def self.active_queues
 
     def self.stop
       if File.exist?(SIDEKIQ_PID_FILE)
-        pid = File.read(SIDEKIQ_PID_FILE).to_i
+        pid = read_pid
         begin
           Process.kill('TERM', pid)
           # Wait for graceful shutdown
@@ -62,7 +62,7 @@ def self.restart
 
     def self.running?
       if File.exist?(SIDEKIQ_PID_FILE)
-        pid = File.read(SIDEKIQ_PID_FILE).to_i
+        pid = read_pid
         process_running?(pid)
       else
         false
@@ -72,12 +72,18 @@ def self.running?
     def self.process_running?(pid)
       Process.kill(0, pid)
       true
-    rescue Errno::ESRCH, Errno::EPERM
+    rescue Errno::ESRCH, Errno::EPERM, Errno::EINVAL
       false
     end
 
     def self.pids
-      running? ? [File.read(SIDEKIQ_PID_FILE).to_i] : []
+      running? ? [read_pid] : []
+    end
+
+    private
+
+    def self.read_pid
+      File.read(SIDEKIQ_PID_FILE).to_i
     end
   end
 end

From f71e15a31360ca6be84ea3d2ac5362d8693e42e4 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Fri, 5 Dec 2025 12:55:20 +0000
Subject: [PATCH 5/5] Add migration to drop delayed_jobs table and
 documentation

- Create migration to drop delayed_jobs table
- Add comprehensive migration notes for users upgrading to Sidekiq
- Document Redis requirements and setup steps
- Document troubleshooting and rollback procedures

Co-authored-by: fbacall <503373+fbacall@users.noreply.github.com>
---
 MIGRATION_NOTES_SIDEKIQ.md                    | 118 ++++++++++++++++++
 .../20251205000000_drop_delayed_jobs_table.rb |  10 ++
 2 files changed, 128 insertions(+)
 create mode 100644 MIGRATION_NOTES_SIDEKIQ.md
 create mode 100644 db/migrate/20251205000000_drop_delayed_jobs_table.rb

diff --git a/MIGRATION_NOTES_SIDEKIQ.md b/MIGRATION_NOTES_SIDEKIQ.md
new file mode 100644
index 0000000000..c6008b3a3d
--- /dev/null
+++ b/MIGRATION_NOTES_SIDEKIQ.md
@@ -0,0 +1,118 @@
+# Migration from delayed_job to Sidekiq
+
+This document outlines the migration from delayed_job to Sidekiq for background job processing in SEEK.
+
+## What Changed
+
+SEEK has migrated from using delayed_job with ActiveRecord backend to Sidekiq with Redis for background job processing. This provides:
+- Better performance and scalability
+- More efficient resource usage
+- Modern, actively maintained job processing system
+
+## Requirements
+
+### New Dependency: Redis
+
+Sidekiq requires Redis to be running. Redis is a fast in-memory data store used for job queuing.
+
+**For Docker users:** The docker-compose.yml files have been updated to include a Redis service automatically.
+
+**For local/manual installations:**
+1. Install Redis:
+   - Ubuntu/Debian: `sudo apt-get install redis-server`
+   - macOS: `brew install redis`
+   - Or download from: https://redis.io/download
+
+2. Start Redis:
+   - Ubuntu/Debian: `sudo systemctl start redis-server`
+   - macOS: `brew services start redis`
+
+3. Verify Redis is running: `redis-cli ping` (should respond with "PONG")
+
+### Environment Variables
+
+Set the `REDIS_URL` environment variable if Redis is not running on localhost:6379:
+```bash
+export REDIS_URL=redis://your-redis-host:6379/0
+```
+
+## Migration Steps
+
+### 1. Update Dependencies
+```bash
+bundle install
+```
+
+### 2. Migrate Database (Optional)
+The migration will drop the old `delayed_jobs` table which is no longer needed:
+```bash
+bundle exec rake db:migrate
+```
+
+### 3. Restart Workers
+If you're running workers separately, restart them:
+```bash
+bundle exec rake seek:workers:restart
+```
+
+For Docker deployments, restart the seek_workers container:
+```bash
+docker-compose restart seek_workers
+```
+
+## What Stays the Same
+
+- All rake tasks remain unchanged: `rake seek:workers:start`, `rake seek:workers:stop`, `rake seek:workers:restart`
+- Admin interface for restarting workers remains the same
+- Queue names and job priorities remain the same
+- Job execution behavior remains the same (single retry, 24-hour timeout)
+
+## Monitoring
+
+### Sidekiq Web UI (Optional)
+
+Sidekiq provides a web interface for monitoring jobs. To enable it, you can mount it in your routes.rb:
+
+```ruby
+require 'sidekiq/web'
+mount Sidekiq::Web => '/sidekiq'
+```
+
+**Note:** Make sure to protect this route with authentication in production!
+
+### Logs
+
+Sidekiq logs are written to `log/sidekiq.log` (instead of the previous delayed_job logs).
+
+### Checking Status
+
+Check if Sidekiq is running:
+```bash
+bundle exec rake seek:workers:status
+```
+
+## Troubleshooting
+
+### "Connection refused" errors
+- Ensure Redis is running: `redis-cli ping`
+- Check REDIS_URL environment variable is set correctly
+
+### Jobs not processing
+- Check Sidekiq is running: `bundle exec rake seek:workers:status`
+- Check Sidekiq logs: `tail -f log/sidekiq.log`
+- Check Redis is accessible: `redis-cli ping`
+
+### Migration Issues
+If you encounter issues with the migration:
+1. Ensure all old delayed_job workers are stopped
+2. Ensure Redis is running
+3. Check the logs for specific error messages
+
+## Rolling Back
+
+If you need to roll back to delayed_job:
+1. Restore the previous version of the code
+2. Run `bundle install`
+3. Restart the application and workers
+
+Note: Any jobs that were queued in Redis will need to be re-queued.
diff --git a/db/migrate/20251205000000_drop_delayed_jobs_table.rb b/db/migrate/20251205000000_drop_delayed_jobs_table.rb
new file mode 100644
index 0000000000..cbecd1a531
--- /dev/null
+++ b/db/migrate/20251205000000_drop_delayed_jobs_table.rb
@@ -0,0 +1,10 @@
+class DropDelayedJobsTable < ActiveRecord::Migration[7.2]
+  def up
+    drop_table :delayed_jobs if table_exists?(:delayed_jobs)
+  end
+
+  def down
+    # Cannot recreate the table structure and data, migration is not reversible
+    raise ActiveRecord::IrreversibleMigration
+  end
+end