diff --git a/.rubocop_todo/gitlab/bounded_contexts.yml b/.rubocop_todo/gitlab/bounded_contexts.yml
index c7736232911350e3d981b88cd16753180d90d6ed..a225956af4e543946bd3371aba10407e7d644281 100644
--- a/.rubocop_todo/gitlab/bounded_contexts.yml
+++ b/.rubocop_todo/gitlab/bounded_contexts.yml
@@ -3529,12 +3529,8 @@ Gitlab/BoundedContexts:
     - 'ee/lib/elastic/latest/config.rb'
     - 'ee/lib/elastic/latest/custom_language_analyzers.rb'
     - 'ee/lib/elastic/latest/document_should_be_deleted_from_index_error.rb'
-    - 'ee/lib/elastic/latest/epic_config.rb'
-    - 'ee/lib/elastic/latest/epic_instance_proxy.rb'
     - 'ee/lib/elastic/latest/git_class_proxy.rb'
     - 'ee/lib/elastic/latest/git_instance_proxy.rb'
-    - 'ee/lib/elastic/latest/issue_config.rb'
-    - 'ee/lib/elastic/latest/issue_instance_proxy.rb'
     - 'ee/lib/elastic/latest/merge_request_class_proxy.rb'
     - 'ee/lib/elastic/latest/merge_request_config.rb'
     - 'ee/lib/elastic/latest/merge_request_instance_proxy.rb'
diff --git a/.rubocop_todo/rspec/named_subject.yml b/.rubocop_todo/rspec/named_subject.yml
index e8ab67a7e962c5f1a1c1b0ca1004fcad738b7b43..5bbcfef578d67e8b9d063593593c1f7b4a3f1bf0 100644
--- a/.rubocop_todo/rspec/named_subject.yml
+++ b/.rubocop_todo/rspec/named_subject.yml
@@ -261,7 +261,6 @@ RSpec/NamedSubject:
     - 'ee/spec/lib/ee/sidebars/projects/menus/security_compliance_menu_spec.rb'
     - 'ee/spec/lib/ee/sidebars/projects/menus/settings_menu_spec.rb'
     - 'ee/spec/lib/elastic/latest/application_instance_proxy_spec.rb'
-    - 'ee/spec/lib/elastic/latest/epic_instance_proxy_spec.rb'
     - 'ee/spec/lib/elastic/latest/git_instance_proxy_spec.rb'
     - 'ee/spec/lib/elastic/latest/routing_spec.rb'
     - 'ee/spec/lib/elastic/latest/snippet_instance_proxy_spec.rb'
diff --git a/.rubocop_todo/search/namespaced_class.yml b/.rubocop_todo/search/namespaced_class.yml
index 402cca32971580dd53ce9da9d24fd1066bb9f583..e7c31ab65bfc599e20da3652e171affc4f62776d 100644
--- a/.rubocop_todo/search/namespaced_class.yml
+++ b/.rubocop_todo/search/namespaced_class.yml
@@ -74,12 +74,8 @@ Search/NamespacedClass:
     - 'ee/lib/elastic/latest/config.rb'
     - 'ee/lib/elastic/latest/custom_language_analyzers.rb'
     - 'ee/lib/elastic/latest/document_should_be_deleted_from_index_error.rb'
-    - 'ee/lib/elastic/latest/epic_config.rb'
-    - 'ee/lib/elastic/latest/epic_instance_proxy.rb'
     - 'ee/lib/elastic/latest/git_class_proxy.rb'
     - 'ee/lib/elastic/latest/git_instance_proxy.rb'
-    - 'ee/lib/elastic/latest/issue_config.rb'
-    - 'ee/lib/elastic/latest/issue_instance_proxy.rb'
     - 'ee/lib/elastic/latest/merge_request_class_proxy.rb'
     - 'ee/lib/elastic/latest/merge_request_config.rb'
     - 'ee/lib/elastic/latest/merge_request_instance_proxy.rb'
diff --git a/doc/integration/advanced_search/elasticsearch.md b/doc/integration/advanced_search/elasticsearch.md
index bd9852e7deb3856967d6d07f0835f20250dda453..a325577aebdda86f03ec43b69270956398d549a7 100644
--- a/doc/integration/advanced_search/elasticsearch.md
+++ b/doc/integration/advanced_search/elasticsearch.md
@@ -496,7 +496,6 @@ To index specific data, use the following Rake tasks:
 
 ```shell
 # For installations that use the Linux package
-sudo gitlab-rake gitlab:elastic:index_epics
 sudo gitlab-rake gitlab:elastic:index_work_items
 sudo gitlab-rake gitlab:elastic:index_group_wikis
 sudo gitlab-rake gitlab:elastic:index_namespaces
@@ -505,7 +504,6 @@ sudo gitlab-rake gitlab:elastic:index_snippets
 sudo gitlab-rake gitlab:elastic:index_users
 
 # For self-compiled installations
-bundle exec rake gitlab:elastic:index_epics RAILS_ENV=production
 bundle exec rake gitlab:elastic:index_work_items RAILS_ENV=production
 bundle exec rake gitlab:elastic:index_group_wikis RAILS_ENV=production
 bundle exec rake gitlab:elastic:index_namespaces RAILS_ENV=production
@@ -1002,16 +1000,18 @@ The following are some available Rake tasks:
 | [`sudo gitlab-rake gitlab:elastic:resume_indexing`](https://gitlab.com/gitlab-org/gitlab/-/blob/master/ee/lib/tasks/gitlab/elastic.rake)                   | Resumes indexing for advanced search. |
 | [`sudo gitlab-rake gitlab:elastic:index_and_search_validation`](https://gitlab.com/gitlab-org/gitlab/-/blob/master/ee/lib/tasks/gitlab/elastic.rake)       | Validates cluster connectivity, index, and search operations for all indices. [Introduced](https://gitlab.com/gitlab-org/gitlab/-/merge_requests/200664) in GitLab 18.3. |
 | [`sudo gitlab-rake gitlab:elastic:index_projects`](https://gitlab.com/gitlab-org/gitlab/-/blob/master/ee/lib/tasks/gitlab/elastic.rake)                    | Iterates over all projects, and queues Sidekiq jobs to index them in the background. It can only be used after the index is created. |
-| [`sudo gitlab-rake gitlab:elastic:index_group_entities`](https://gitlab.com/gitlab-org/gitlab/-/blob/master/ee/lib/tasks/gitlab/elastic.rake)              | Invokes `gitlab:elastic:index_epics` and `gitlab:elastic:index_group_wikis`. |
-| [`sudo gitlab-rake gitlab:elastic:index_epics`](https://gitlab.com/gitlab-org/gitlab/-/blob/master/ee/lib/tasks/gitlab/elastic.rake)                       | Indexes all epics from the groups where Elasticsearch is enabled. |
+| [`sudo gitlab-rake gitlab:elastic:index_group_entities`](https://gitlab.com/gitlab-org/gitlab/-/blob/master/ee/lib/tasks/gitlab/elastic.rake)              | Invokes `gitlab:elastic:index_work_items` and `gitlab:elastic:index_group_wikis`. |
+| [`sudo gitlab-rake gitlab:elastic:index_work_items`](https://gitlab.com/gitlab-org/gitlab/-/blob/master/ee/lib/tasks/gitlab/elastic.rake)                   | Indexes all work items from the groups where Elasticsearch is enabled. |
+| [`sudo gitlab-rake gitlab:elastic:index_namespaces`](https://gitlab.com/gitlab-org/gitlab/-/blob/master/ee/lib/tasks/gitlab/elastic.rake)                   | Indexes all root namespaces. |
 | [`sudo gitlab-rake gitlab:elastic:index_group_wikis`](https://gitlab.com/gitlab-org/gitlab/-/blob/master/ee/lib/tasks/gitlab/elastic.rake)                 | Indexes all wikis from the groups where Elasticsearch is enabled. |
+| [`sudo gitlab-rake gitlab:elastic:index_snippets`](https://gitlab.com/gitlab-org/gitlab/-/blob/master/ee/lib/tasks/gitlab/elastic.rake)                    | Performs an Elasticsearch import that indexes the snippets data. |
+| [`sudo gitlab-rake gitlab:elastic:index_users`](https://gitlab.com/gitlab-org/gitlab/-/blob/master/ee/lib/tasks/gitlab/elastic.rake)                       | Imports all users into Elasticsearch. |
+| [`sudo gitlab-rake gitlab:elastic:index_vulnerabilities`](https://gitlab.com/gitlab-org/gitlab/-/blob/master/ee/lib/tasks/gitlab/elastic.rake)             | Indexes all vulnerabilities. |
 | [`sudo gitlab-rake gitlab:elastic:index_projects_status`](https://gitlab.com/gitlab-org/gitlab/-/blob/master/ee/lib/tasks/gitlab/elastic.rake)             | Determines the overall indexing status of all project repository data (code, commits, and wikis). The status is calculated by dividing the number of indexed projects by the total number of projects and multiplying by 100. This task does not include non-repository data such as issues, merge requests, or milestones. |
 | [`sudo gitlab-rake gitlab:elastic:clear_index_status`](https://gitlab.com/gitlab-org/gitlab/-/blob/master/ee/lib/tasks/gitlab/elastic.rake)                | Deletes all instances of IndexStatus for all projects. This command results in a complete wipe of the index, and it should be used with caution. |
 | [`sudo gitlab-rake gitlab:elastic:create_empty_index`](https://gitlab.com/gitlab-org/gitlab/-/blob/master/ee/lib/tasks/gitlab/elastic.rake)                | Generates empty indices (the default index and a separate issues index) and assigns an alias for each on the Elasticsearch side only if it doesn't already exist. |
 | [`sudo gitlab-rake gitlab:elastic:delete_index`](https://gitlab.com/gitlab-org/gitlab/-/blob/master/ee/lib/tasks/gitlab/elastic.rake)                      | Removes the GitLab indices and aliases (if they exist) on the Elasticsearch instance. |
 | [`sudo gitlab-rake gitlab:elastic:recreate_index`](https://gitlab.com/gitlab-org/gitlab/-/blob/master/ee/lib/tasks/gitlab/elastic.rake)                    | Wrapper task for `gitlab:elastic:delete_index` and `gitlab:elastic:create_empty_index`. Does not queue any indexing jobs. |
-| [`sudo gitlab-rake gitlab:elastic:index_snippets`](https://gitlab.com/gitlab-org/gitlab/-/blob/master/ee/lib/tasks/gitlab/elastic.rake)                    | Performs an Elasticsearch import that indexes the snippets data. |
-| [`sudo gitlab-rake gitlab:elastic:index_users`](https://gitlab.com/gitlab-org/gitlab/-/blob/master/ee/lib/tasks/gitlab/elastic.rake)                       | Imports all users into Elasticsearch. |
 | [`sudo gitlab-rake gitlab:elastic:projects_not_indexed`](https://gitlab.com/gitlab-org/gitlab/-/blob/master/ee/lib/tasks/gitlab/elastic.rake)              | Displays which projects do not have repository data indexed. This task does not include non-repository data such as issues, merge requests, or milestones. |
 | [`sudo gitlab-rake gitlab:elastic:reindex_cluster`](https://gitlab.com/gitlab-org/gitlab/-/blob/master/ee/lib/tasks/gitlab/elastic.rake)                   | Schedules a zero-downtime cluster reindexing task. |
 | [`sudo gitlab-rake gitlab:elastic:mark_reindex_failed`](https://gitlab.com/gitlab-org/gitlab/-/blob/master/ee/lib/tasks/gitlab/elastic.rake)               | Mark the most recent reindex job as failed. |
@@ -1245,17 +1245,17 @@ due to large volumes of data being indexed:
    indexer to "forget" all progress, so it retries the indexing process from the
    start.
 
-1. Epics, group wikis, personal snippets, and users are not associated with a project and must be indexed separately:
+1. Work items, group wikis, personal snippets, and users are not associated with a project and must be indexed separately:
 
    ```shell
    # For installations that use the Linux package
-   sudo gitlab-rake gitlab:elastic:index_epics
+   sudo gitlab-rake gitlab:elastic:index_work_items
    sudo gitlab-rake gitlab:elastic:index_group_wikis
    sudo gitlab-rake gitlab:elastic:index_snippets
    sudo gitlab-rake gitlab:elastic:index_users
 
    # For self-compiled installations
-   bundle exec rake gitlab:elastic:index_epics RAILS_ENV=production
+   bundle exec rake gitlab:elastic:index_work_items RAILS_ENV=production
    bundle exec rake gitlab:elastic:index_group_wikis RAILS_ENV=production
    bundle exec rake gitlab:elastic:index_snippets RAILS_ENV=production
    bundle exec rake gitlab:elastic:index_users RAILS_ENV=production
diff --git a/ee/app/models/concerns/search/elastic/issues_search.rb b/ee/app/models/concerns/search/elastic/issues_search.rb
index e49a1b930d9b49d88dda734bfd6211a9baf71c3c..589d361eccb7403511dee064fb77ac98d1a084a4 100644
--- a/ee/app/models/concerns/search/elastic/issues_search.rb
+++ b/ee/app/models/concerns/search/elastic/issues_search.rb
@@ -24,6 +24,10 @@ def maintain_elasticsearch_update(updated_attributes: previous_changes.keys)
           track_embedding! if (updated_attributes.map(&:to_sym) & EMBEDDING_TRACKED_FIELDS).any? && track_embedding?
         end
 
+        def es_id
+          ::Gitlab::Elastic::Helper.build_es_id(es_type: es_type, target_id: id)
+        end
+
         private
 
         # rubocop: disable Gitlab/FeatureFlagWithoutActor -- global flags
diff --git a/ee/app/models/ee/epic.rb b/ee/app/models/ee/epic.rb
index b5dd67a5f6386e16a352cc834445c53cab8180a7..72a142c94391dc1da97db3b85d22ca8f6f41216f 100644
--- a/ee/app/models/ee/epic.rb
+++ b/ee/app/models/ee/epic.rb
@@ -370,11 +370,6 @@ def search(query)
         fuzzy_search(query, [:title, :description])
       end
 
-      override :use_separate_indices?
-      def use_separate_indices?
-        true
-      end
-
       def ids_for_base_and_decendants(epic_ids)
         ::Gitlab::ObjectHierarchy.new(self.id_in(epic_ids)).base_and_descendants.pluck(:id)
       end
diff --git a/ee/app/models/ee/issue.rb b/ee/app/models/ee/issue.rb
index 99edfda639a048b1219efb08854a4b8c56099318..0f0958e3ae15a16b47283e90582785c25b666e4a 100644
--- a/ee/app/models/ee/issue.rb
+++ b/ee/app/models/ee/issue.rb
@@ -171,11 +171,6 @@ def with_api_entity_associations
         super.preload(:sync_object, epic: { group: :route }, iteration: { group: :route })
       end
 
-      # override
-      def use_separate_indices?
-        true
-      end
-
       # override
       def supported_keyset_orderings
         super.merge(weight: [:asc, :desc])
@@ -219,6 +214,10 @@ def elastic_reference
       ::Search::Elastic::References::WorkItem.serialize(self)
     end
 
+    def self.es_type
+      ::Search::Elastic::References::WorkItem::DOC_TYPE
+    end
+
     override :maintain_elasticsearch_update
     def maintain_elasticsearch_update(updated_attributes: previous_changes.keys)
       super
diff --git a/ee/app/services/search/rake_task_executor_service.rb b/ee/app/services/search/rake_task_executor_service.rb
index 97ef476fae5245b33f8f321c751fe58844c033d6..11774e0cfd0dab08af74716da8277b40c1736566 100644
--- a/ee/app/services/search/rake_task_executor_service.rb
+++ b/ee/app/services/search/rake_task_executor_service.rb
@@ -14,7 +14,6 @@ class RakeTaskExecutorService
       estimate_cluster_size
       estimate_shard_sizes
       index_and_search_validation
-      index_epics
       index_work_items
       index_group_entities
       index_group_wikis
@@ -386,28 +385,10 @@ def index_projects
       logger.info(" #{marker} (#{count})")
     end
 
-    def index_epics
-      logger.info('Indexing epics...')
-
-      groups = if ::Gitlab::CurrentSettings.elasticsearch_limit_indexing?
-                 ::Gitlab::CurrentSettings.elasticsearch_limited_namespaces.group_namespaces
-               else
-                 Group.all
-               end
-
-      groups.each_batch do |batch|
-        ::Elastic::ProcessInitialBookkeepingService.maintain_indexed_namespace_associations!(*batch,
-          associations_to_index: [:epics])
-      end
-
-      logger.info("Indexing epics... #{Rainbow('done').green}")
-    end
-
     def index_group_entities
       raise 'This task cannot be run on GitLab.com' if ::Gitlab::Saas.feature_available?(:advanced_search)
 
       logger.info('Enqueuing Group level entities…')
-      index_epics
       index_work_items
       index_group_wikis
     end
diff --git a/ee/elastic/migrate/20231130152447_add_work_item_type_id_to_issues.rb b/ee/elastic/migrate/20231130152447_add_work_item_type_id_to_issues.rb
deleted file mode 100644
index 2dc558cce006d3eed7581983649ffc18e00f5885..0000000000000000000000000000000000000000
--- a/ee/elastic/migrate/20231130152447_add_work_item_type_id_to_issues.rb
+++ /dev/null
@@ -1,21 +0,0 @@
-# frozen_string_literal: true
-
-class AddWorkItemTypeIdToIssues < Elastic::Migration
-  include ::Search::Elastic::MigrationUpdateMappingsHelper
-
-  private
-
-  def index_name
-    ::Elastic::Latest::IssueConfig.index_name
-  end
-
-  def new_mappings
-    {
-      work_item_type_id: {
-        type: 'integer'
-      }
-    }
-  end
-end
-
-AddWorkItemTypeIdToIssues.prepend ::Search::Elastic::MigrationObsolete
diff --git a/ee/lib/elastic/class_proxy_util.rb b/ee/lib/elastic/class_proxy_util.rb
index 807a25b3fe1f8aefe23117b6049aca4b9ba07ed5..6b33e97189f58de234e810a582af7eb0833ab1a7 100644
--- a/ee/lib/elastic/class_proxy_util.rb
+++ b/ee/lib/elastic/class_proxy_util.rb
@@ -14,7 +14,6 @@ def initialize(target, use_separate_indices: false)
       # use_separate_indices check is needed to load custom mappings for AR and non-AR classes
       # For example, Issue and Commit
       const_name = use_separate_indices ? "#{target.base_class}Config" : 'Config'
-
       config = version_namespace.const_get(const_name, false)
 
       @index_name = config.index_name
diff --git a/ee/lib/elastic/latest/epic_config.rb b/ee/lib/elastic/latest/epic_config.rb
deleted file mode 100644
index 06200bd706cff6e5d4d839d035df81144f2141e2..0000000000000000000000000000000000000000
--- a/ee/lib/elastic/latest/epic_config.rb
+++ /dev/null
@@ -1,43 +0,0 @@
-# frozen_string_literal: true
-
-module Elastic
-  module Latest
-    module EpicConfig
-      extend Elasticsearch::Model::Indexing::ClassMethods
-      extend Elasticsearch::Model::Naming::ClassMethods
-
-      def self.index_name
-        [Gitlab::CurrentSettings.elasticsearch_prefix, Rails.env, 'epics'].join('-')
-      end
-
-      settings Elastic::Latest::Config.settings.to_hash.deep_merge(
-        index: Elastic::Latest::Config.separate_index_specific_settings(index_name)
-      )
-
-      mappings dynamic: 'strict' do
-        indexes :id, type: :integer
-        indexes :iid, type: :integer
-        indexes :group_id, type: :long
-
-        indexes :created_at, type: :date
-        indexes :updated_at, type: :date
-
-        indexes :title, type: :text, index_options: 'positions', analyzer: :title_analyzer
-        indexes :description, type: :text, index_options: 'positions', analyzer: :code_analyzer
-        indexes :state, type: :keyword
-        indexes :confidential, type: :boolean
-        indexes :author_id, type: :integer
-        indexes :label_ids, type: :keyword
-        indexes :start_date, type: :date
-        indexes :due_date, type: :date
-
-        indexes :traversal_ids, type: :keyword
-        indexes :hashed_root_namespace_id, type: :integer
-        indexes :visibility_level, type: :integer
-
-        indexes :schema_version, type: :short
-        indexes :type, type: :keyword
-      end
-    end
-  end
-end
diff --git a/ee/lib/elastic/latest/epic_instance_proxy.rb b/ee/lib/elastic/latest/epic_instance_proxy.rb
deleted file mode 100644
index b335772b9d1fae83aff550252c13641703bae36d..0000000000000000000000000000000000000000
--- a/ee/lib/elastic/latest/epic_instance_proxy.rb
+++ /dev/null
@@ -1,50 +0,0 @@
-# frozen_string_literal: true
-
-module Elastic
-  module Latest
-    class EpicInstanceProxy < ApplicationInstanceProxy
-      SCHEMA_VERSION = 24_01
-
-      def as_indexed_json(_options = {})
-        data = {}
-
-        [
-          :id,
-          :iid,
-          :group_id,
-          :created_at,
-          :updated_at,
-          :title,
-          :description,
-          :state,
-          :confidential,
-          :author_id
-        ].each do |attr|
-          data[attr.to_s] = safely_read_attribute_for_elasticsearch(attr)
-        end
-
-        data['label_ids'] = target.label_ids.map(&:to_s)
-        data['start_date'] = target.start_date || target.start_date_from_inherited_source
-        data['due_date'] = target.end_date || target.due_date_from_inherited_source
-
-        data['traversal_ids'] = target.group.elastic_namespace_ancestry
-        data['hashed_root_namespace_id'] = target.group.hashed_root_namespace_id
-        data['visibility_level'] = target.group.visibility_level
-
-        # Schema version. The format is Date.today.strftime('%y_%m')
-        # Please update if you're changing the schema of the document
-        data['schema_version'] = SCHEMA_VERSION
-
-        data.merge(generic_attributes)
-      end
-
-      def generic_attributes
-        super.except('join_field')
-      end
-
-      def es_parent
-        "group_#{group.root_ancestor.id}"
-      end
-    end
-  end
-end
diff --git a/ee/lib/elastic/latest/issue_config.rb b/ee/lib/elastic/latest/issue_config.rb
deleted file mode 100644
index 9986a3f9d9d92e73a7f5d0f03b8adc33a608aba6..0000000000000000000000000000000000000000
--- a/ee/lib/elastic/latest/issue_config.rb
+++ /dev/null
@@ -1,52 +0,0 @@
-# frozen_string_literal: true
-
-module Elastic
-  module Latest
-    module IssueConfig
-      # To obtain settings and mappings methods
-      extend Elasticsearch::Model::Indexing::ClassMethods
-      extend Elasticsearch::Model::Naming::ClassMethods
-
-      def self.index_name
-        [Gitlab::CurrentSettings.elasticsearch_prefix, Rails.env, 'issues'].join('-')
-      end
-
-      settings Elastic::Latest::Config.settings.to_hash.deep_merge(
-        index: {
-          number_of_shards: Elastic::AsJSON.new { Elastic::IndexSetting[index_name].number_of_shards },
-          number_of_replicas: Elastic::AsJSON.new { Elastic::IndexSetting[index_name].number_of_replicas }
-        }
-      )
-
-      mappings dynamic: 'strict' do
-        indexes :type, type: :keyword
-
-        indexes :id, type: :integer
-        indexes :iid, type: :integer
-
-        indexes :title, type: :text, index_options: 'positions', analyzer: :title_analyzer
-        indexes :description, type: :text, index_options: 'positions', analyzer: :code_analyzer
-        indexes :created_at, type: :date
-        indexes :updated_at, type: :date
-        indexes :state, type: :keyword
-        indexes :project_id, type: :integer
-        indexes :author_id, type: :integer
-        indexes :confidential, type: :boolean
-        indexes :hidden, type: :boolean
-        indexes :archived, type: :boolean
-        indexes :assignee_id, type: :integer
-
-        indexes :visibility_level, type: :integer
-        indexes :issues_access_level, type: :integer
-        indexes :upvotes, type: :integer
-        indexes :namespace_ancestry_ids, type: :keyword
-        indexes :label_ids, type: :keyword
-        indexes :hashed_root_namespace_id, type: :integer
-        indexes :work_item_type_id, type: :integer
-        indexes :routing, type: :keyword
-
-        indexes :schema_version, type: :short
-      end
-    end
-  end
-end
diff --git a/ee/lib/elastic/latest/issue_instance_proxy.rb b/ee/lib/elastic/latest/issue_instance_proxy.rb
deleted file mode 100644
index 9cb46e459eccaf360506cf974ed999e729035f62..0000000000000000000000000000000000000000
--- a/ee/lib/elastic/latest/issue_instance_proxy.rb
+++ /dev/null
@@ -1,57 +0,0 @@
-# frozen_string_literal: true
-
-module Elastic
-  module Latest
-    class IssueInstanceProxy < ApplicationInstanceProxy
-      SCHEMA_VERSION = 24_08
-      OPTIONAL_FIELDS = %w[embedding embedding_version].freeze
-
-      def as_indexed_json(_options = {})
-        data = {}
-
-        return data unless target.project_id
-
-        # We don't use as_json(only: ...) because it calls all virtual and serialized attributes
-        # https://gitlab.com/gitlab-org/gitlab/issues/349
-        [:id, :iid, :title, :description, :created_at, :updated_at, :state, :project_id, :author_id,
-          :confidential].each do |attr|
-          data[attr.to_s] = safely_read_attribute_for_elasticsearch(attr)
-        end
-
-        # Schema version. The format is Date.today.strftime('%y_%m')
-        # Please update if you're changing the schema of the document
-        data['schema_version'] = SCHEMA_VERSION
-
-        # Load them through the issue_assignees table since calling
-        # assignee_ids can't be easily preloaded and does
-        # unnecessary joins
-        data['assignee_id'] = safely_read_attribute_for_elasticsearch(:issue_assignee_user_ids)
-        data['hidden'] = target.hidden?
-        data['visibility_level'] = target.project.visibility_level
-        data['issues_access_level'] = safely_read_project_feature_for_elasticsearch(:issues)
-
-        data['upvotes'] = target.upvotes_count
-        data['namespace_ancestry_ids'] = target.namespace_ancestry
-        data['label_ids'] = target.label_ids.map(&:to_s)
-
-        data['hashed_root_namespace_id'] = target.project.namespace.hashed_root_namespace_id
-        data['archived'] = target.project.archived?
-        data['work_item_type_id'] = target.work_item_type_id
-
-        data['routing'] = es_parent
-
-        data.merge(generic_attributes)
-      end
-
-      def es_id
-        target.id.to_s
-      end
-
-      private
-
-      def generic_attributes
-        super.except('join_field')
-      end
-    end
-  end
-end
diff --git a/ee/lib/elastic/multi_version_util.rb b/ee/lib/elastic/multi_version_util.rb
index ce16125f0bea80d085befbe3ba6fdd6e678a20c6..6fe9bfd8faec9e8cd87aea94a45255cf110fcd31 100644
--- a/ee/lib/elastic/multi_version_util.rb
+++ b/ee/lib/elastic/multi_version_util.rb
@@ -13,7 +13,6 @@ module MultiVersionUtil
     # @params version [String, Module] can be a string "V12p1" or module (Elastic::V12p1)
     def version(version)
       version = Elastic.const_get(version, false) if version.is_a?(String)
-
       proxy_class = if version.const_defined?(proxy_class_name, false)
                       version.const_get(proxy_class_name, false)
                     else
diff --git a/ee/lib/gitlab/elastic/document_reference.rb b/ee/lib/gitlab/elastic/document_reference.rb
index 0cd3955ad96b389b5e0163e0c859dcbb87fa031e..469d2227e5544f02e273dd9ec42118fbc30a30cd 100644
--- a/ee/lib/gitlab/elastic/document_reference.rb
+++ b/ee/lib/gitlab/elastic/document_reference.rb
@@ -145,7 +145,7 @@ def klass_proxy
       private
 
       def index_operation
-        return :upsert if klass == Issue
+        return :upsert if [Issue, Epic, WorkItem].include?(klass)
 
         :index
       end
diff --git a/ee/lib/gitlab/elastic/helper.rb b/ee/lib/gitlab/elastic/helper.rb
index 318626ab64b6dae0d053749565fb421a4d823b95..7ad6a6b509e270891721919345aa3e24b9b980fd 100644
--- a/ee/lib/gitlab/elastic/helper.rb
+++ b/ee/lib/gitlab/elastic/helper.rb
@@ -4,11 +4,9 @@ module Gitlab
   module Elastic
     class Helper
       ES_SEPARATE_CLASSES = [
-        Issue,
         Note,
         MergeRequest,
         Commit,
-        Epic,
         User,
         Wiki,
         Project,
@@ -364,9 +362,11 @@ def target_index_names(target:)
       def klass_to_alias_name(klass:)
         return target_name if klass == Repository
 
-        proxy_klass = self.class.type_class(klass) || ::Elastic::Latest::ApplicationClassProxy.new(klass,
-          use_separate_indices: true)
-        proxy_klass.index_name
+        # If klass is already a proxy object, just return its index_name
+        return klass.index_name if klass.is_a?(::Elasticsearch::Model::Proxy::ClassMethodsProxy)
+
+        (self.class.type_class(klass) || ::Elastic::Latest::ApplicationClassProxy.new(klass,
+          use_separate_indices: true)).index_name
       end
 
       # handles unreachable hosts and any other exceptions that may be raised
diff --git a/ee/lib/search/elastic/references/embedding.rb b/ee/lib/search/elastic/references/embedding.rb
index 105eddf95c0ca711c880ccdc1b4a7b262eec27ee..d4e6ca94b32536606c7a7b2e291419aacef47914 100644
--- a/ee/lib/search/elastic/references/embedding.rb
+++ b/ee/lib/search/elastic/references/embedding.rb
@@ -20,7 +20,8 @@ def self.serialize(record)
         end
 
         def self.ref(record)
-          new(record.class, record.id, record.es_parent)
+          klass = record.instance_of?(::Issue) ? ::WorkItem : record.class
+          new(klass, record.id, record.es_parent)
         end
 
         override :instantiate
diff --git a/ee/lib/search/elastic/references/work_item.rb b/ee/lib/search/elastic/references/work_item.rb
index a44a3e852d4fc3fec544bdb52847ce253b459c77..6c165d62ff70bc706d93e03fb8a4962915835828 100644
--- a/ee/lib/search/elastic/references/work_item.rb
+++ b/ee/lib/search/elastic/references/work_item.rb
@@ -62,6 +62,8 @@ class WorkItem < Reference
           any_health_status
         ].freeze
 
+        DOC_TYPE = 'work_item'
+
         override :serialize
         def self.serialize(record)
           new(record.id, record.es_parent).serialize
diff --git a/ee/lib/tasks/gitlab/elastic.rake b/ee/lib/tasks/gitlab/elastic.rake
index a1605ab2dc344d13d1b14b37163d66009993f210..9c17b3156ed7038f395e4274db9f7f79ed162aaa 100644
--- a/ee/lib/tasks/gitlab/elastic.rake
+++ b/ee/lib/tasks/gitlab/elastic.rake
@@ -67,9 +67,14 @@ namespace :gitlab do
       Search::RakeTask::Elastic.task_executor_service.execute(:index_users)
     end
 
-    desc 'GitLab | Elasticsearch | Index epics'
-    task index_epics: :environment do
-      Search::RakeTask::Elastic.task_executor_service.execute(:index_epics)
+    desc 'GitLab | Elasticsearch | Index work items'
+    task index_work_items: :environment do
+      Search::RakeTask::Elastic.task_executor_service.execute(:index_work_items)
+    end
+
+    desc 'GitLab | Elasticsearch | Index namespaces'
+    task index_namespaces: :environment do
+      Search::RakeTask::Elastic.task_executor_service.execute(:index_namespaces)
     end
 
     desc 'GitLab | Elasticsearch | Index group wikis'
diff --git a/ee/spec/elastic/migrate/20231130152447_add_work_item_type_id_to_issues_spec.rb b/ee/spec/elastic/migrate/20231130152447_add_work_item_type_id_to_issues_spec.rb
deleted file mode 100644
index 7f126c66858e6cf6a275500482378a56221a4d49..0000000000000000000000000000000000000000
--- a/ee/spec/elastic/migrate/20231130152447_add_work_item_type_id_to_issues_spec.rb
+++ /dev/null
@@ -1,8 +0,0 @@
-# frozen_string_literal: true
-
-require 'spec_helper'
-require File.expand_path('ee/elastic/migrate/20231130152447_add_work_item_type_id_to_issues.rb')
-
-RSpec.describe AddWorkItemTypeIdToIssues, feature_category: :global_search do
-  it_behaves_like 'a deprecated Advanced Search migration', 20231130152447
-end
diff --git a/ee/spec/features/admin/admin_settings_spec.rb b/ee/spec/features/admin/admin_settings_spec.rb
index 2e484f078bb02c94a2bb08da3d4657cec0dee879..0c0d0b694faffc270920f261d786acc57fb35e7b 100644
--- a/ee/spec/features/admin/admin_settings_spec.rb
+++ b/ee/spec/features/admin/admin_settings_spec.rb
@@ -83,8 +83,6 @@
 
         fill_in 'application_setting_elasticsearch_shards[gitlab-test]', with: '120'
         fill_in 'application_setting_elasticsearch_replicas[gitlab-test]', with: '2'
-        fill_in 'application_setting_elasticsearch_shards[gitlab-test-issues]', with: '10'
-        fill_in 'application_setting_elasticsearch_replicas[gitlab-test-issues]', with: '3'
         fill_in 'application_setting_elasticsearch_shards[gitlab-test-notes]', with: '20'
         fill_in 'application_setting_elasticsearch_replicas[gitlab-test-notes]', with: '4'
         fill_in 'application_setting_elasticsearch_shards[gitlab-test-merge_requests]', with: '15'
@@ -109,8 +107,6 @@
         expect(current_settings.elasticsearch_replicas).to eq(2)
         expect(Elastic::IndexSetting['gitlab-test'].number_of_shards).to eq(120)
         expect(Elastic::IndexSetting['gitlab-test'].number_of_replicas).to eq(2)
-        expect(Elastic::IndexSetting['gitlab-test-issues'].number_of_shards).to eq(10)
-        expect(Elastic::IndexSetting['gitlab-test-issues'].number_of_replicas).to eq(3)
         expect(Elastic::IndexSetting['gitlab-test-notes'].number_of_shards).to eq(20)
         expect(Elastic::IndexSetting['gitlab-test-notes'].number_of_replicas).to eq(4)
         expect(Elastic::IndexSetting['gitlab-test-merge_requests'].number_of_shards).to eq(15)
diff --git a/ee/spec/lib/ee/gitlab/elastic/helper_spec.rb b/ee/spec/lib/ee/gitlab/elastic/helper_spec.rb
index 1185e5b48867c484d7d4cb51be11810c47ce1eb5..5f7f355d68422150fe0bbe906100ac07a0ed7153 100644
--- a/ee/spec/lib/ee/gitlab/elastic/helper_spec.rb
+++ b/ee/spec/lib/ee/gitlab/elastic/helper_spec.rb
@@ -568,7 +568,7 @@
     end
 
     context 'when target_classes is provided' do
-      let(:target_classes) { [Issue] }
+      let(:target_classes) { [WorkItem] }
 
       it 'creates proxies for only the target classes' do
         expect(standalone_indices_proxies.count).to eq(1)
@@ -906,7 +906,7 @@
     end
 
     context 'when index_name is provided' do
-      let(:index_name) { 'gitlab-test-issues' }
+      let(:index_name) { 'gitlab-test-work_items' }
 
       it 'refreshes a single index' do
         expect(helper.client.indices).to receive(:refresh).with(index: index_name)
diff --git a/ee/spec/lib/elastic/latest/epic_config_spec.rb b/ee/spec/lib/elastic/latest/epic_config_spec.rb
deleted file mode 100644
index ac1c266a386a4ac3a4b860a1a710124e35255bc2..0000000000000000000000000000000000000000
--- a/ee/spec/lib/elastic/latest/epic_config_spec.rb
+++ /dev/null
@@ -1,22 +0,0 @@
-# frozen_string_literal: true
-
-require 'spec_helper'
-require_relative './config_shared_examples'
-
-RSpec.describe Elastic::Latest::EpicConfig, feature_category: :global_search do
-  describe '.settings' do
-    it_behaves_like 'config settings return correct values'
-  end
-
-  describe '.mappings' do
-    it 'returns config' do
-      expect(described_class.mapping).to be_a(Elasticsearch::Model::Indexing::Mappings)
-    end
-  end
-
-  describe '.index_name' do
-    it 'includes' do
-      expect(described_class.index_name).to include('-epics')
-    end
-  end
-end
diff --git a/ee/spec/lib/elastic/latest/epic_instance_proxy_spec.rb b/ee/spec/lib/elastic/latest/epic_instance_proxy_spec.rb
deleted file mode 100644
index 381c66edb434d3a10a478a77db2b233f77276d90..0000000000000000000000000000000000000000
--- a/ee/spec/lib/elastic/latest/epic_instance_proxy_spec.rb
+++ /dev/null
@@ -1,77 +0,0 @@
-# frozen_string_literal: true
-
-require 'spec_helper'
-
-RSpec.describe Elastic::Latest::EpicInstanceProxy, feature_category: :global_search do
-  let_it_be(:parent_group) { create(:group) }
-  let_it_be(:group) { create(:group, parent: parent_group) }
-  let_it_be(:label) { create(:group_label, group: group) }
-  let_it_be(:epic) { create(:labeled_epic, :use_fixed_dates, :opened, group: group, labels: [label]) }
-
-  subject { described_class.new(epic) }
-
-  describe '#as_indexed_json' do
-    let(:result) { subject.as_indexed_json.with_indifferent_access }
-
-    it 'serializes the object as a hash' do
-      expect(result).to include(
-        id: epic.id,
-        iid: epic.iid,
-        group_id: group.id,
-        created_at: epic.created_at,
-        updated_at: epic.updated_at,
-        title: epic.title,
-        description: epic.description,
-        state: 'opened',
-        confidential: epic.confidential,
-        author_id: epic.author_id,
-        label_ids: [label.id.to_s],
-        start_date: epic.start_date,
-        due_date: epic.due_date,
-        traversal_ids: "#{parent_group.id}-#{group.id}-",
-        hashed_root_namespace_id: ::Search.hash_namespace_id(parent_group.id),
-        visibility_level: group.visibility_level,
-        schema_version: described_class::SCHEMA_VERSION,
-        type: 'epic'
-      )
-    end
-
-    it 'does not have an N+1 for building the document' do
-      epic = create(:epic, group: group)
-
-      control = ActiveRecord::QueryRecorder.new do
-        epic.__elasticsearch__.as_indexed_json
-      end
-
-      group_with_parent = create(:group, :private, parent: group)
-      epic.update!(group_id: group_with_parent.id)
-
-      expect do
-        epic.__elasticsearch__.as_indexed_json
-      end.not_to exceed_query_limit(control)
-    end
-
-    context 'with start date inherited date from child epic and due date inherited from milestone' do
-      let_it_be(:epic) { create(:epic) }
-      let_it_be(:child_epic) { create(:epic, :use_fixed_dates) }
-      let_it_be(:milestone) { create(:milestone, :with_dates) }
-
-      before do
-        epic.start_date_sourcing_epic = child_epic
-        epic.due_date_sourcing_milestone = milestone
-        epic.save!
-      end
-
-      it 'sets start and due dates to inherited dates' do
-        expect(result[:start_date]).to eq(child_epic.start_date)
-        expect(result[:due_date]).to eq(milestone.due_date)
-      end
-    end
-  end
-
-  describe '#es_parent' do
-    it 'contains group id' do
-      expect(subject.es_parent).to eq("group_#{parent_group.id}")
-    end
-  end
-end
diff --git a/ee/spec/lib/elastic/latest/issue_config_spec.rb b/ee/spec/lib/elastic/latest/issue_config_spec.rb
deleted file mode 100644
index 4b54b2fdd77f2cbe678d579516ab16eb9bdbb8a1..0000000000000000000000000000000000000000
--- a/ee/spec/lib/elastic/latest/issue_config_spec.rb
+++ /dev/null
@@ -1,32 +0,0 @@
-# frozen_string_literal: true
-
-require 'spec_helper'
-require_relative './config_shared_examples'
-
-RSpec.describe Elastic::Latest::IssueConfig, feature_category: :global_search do
-  describe '.settings' do
-    it_behaves_like 'config settings return correct values'
-  end
-
-  describe '.mappings' do
-    it 'returns config' do
-      expect(described_class.mapping).to be_a(Elasticsearch::Model::Indexing::Mappings)
-    end
-  end
-
-  describe '.index_name' do
-    it 'uses the elasticsearch_prefix setting' do
-      allow(Gitlab::CurrentSettings).to receive(:elasticsearch_prefix).and_return('custom-prefix')
-      allow(Rails).to receive(:env).and_return(ActiveSupport::StringInquirer.new('test'))
-
-      expect(described_class.index_name).to eq('custom-prefix-test-issues')
-    end
-
-    it 'uses default prefix when setting returns default value' do
-      allow(Gitlab::CurrentSettings).to receive(:elasticsearch_prefix).and_return('gitlab')
-      allow(Rails).to receive(:env).and_return(ActiveSupport::StringInquirer.new('development'))
-
-      expect(described_class.index_name).to eq('gitlab-development-issues')
-    end
-  end
-end
diff --git a/ee/spec/lib/search/elastic/references/embedding_spec.rb b/ee/spec/lib/search/elastic/references/embedding_spec.rb
index b7f0a46b648320783fceeda8eb58ba7faeb73b39..c2d60d1110d4ffdcddf2afef15eb8e8867184473 100644
--- a/ee/spec/lib/search/elastic/references/embedding_spec.rb
+++ b/ee/spec/lib/search/elastic/references/embedding_spec.rb
@@ -6,8 +6,8 @@
   let_it_be(:project) { create(:project) }
   let_it_be(:issue) { create(:issue, project: project) }
   let(:routing) { issue.es_parent }
-  let(:embedding_ref) { described_class.new(Issue, issue.id, routing) }
-  let(:embedding_ref_serialized) { "Embedding|Issue|#{issue.id}|#{routing}" }
+  let(:embedding_ref) { described_class.new(WorkItem, issue.id, routing) }
+  let(:embedding_ref_serialized) { "Embedding|WorkItem|#{issue.id}|#{routing}" }
   let(:work_item_embedding_ref) { described_class.new(WorkItem, issue.id, routing) }
 
   before do
@@ -29,7 +29,7 @@
       ref = described_class.ref(issue)
 
       expect(ref).to be_an_instance_of(described_class)
-      expect(ref.model_klass).to eq(Issue)
+      expect(ref.model_klass).to eq(WorkItem)
       expect(ref.identifier).to eq(issue.id)
       expect(ref.routing).to eq(routing)
     end
@@ -40,7 +40,7 @@
       ref = described_class.instantiate(embedding_ref_serialized)
 
       expect(ref).to be_an_instance_of(described_class)
-      expect(ref.model_klass).to eq(Issue)
+      expect(ref.model_klass).to eq(WorkItem)
       expect(ref.identifier).to eq(issue.id)
       expect(ref.routing).to eq(routing)
     end
@@ -50,7 +50,7 @@
     let_it_be(:project2) { create(:project) }
     let_it_be(:issue2) { create(:issue, project: project2) }
     let(:embedding_ref2) { described_class.new(WorkItem, issue2.id, "project_#{project2.id}") }
-    let(:embedding_ref3) { described_class.new(Issue, issue2.id, "project_#{project2.id}") }
+    let(:embedding_ref3) { described_class.new(WorkItem, issue2.id, "project_#{project2.id}") }
     let(:embedding_ref4) { described_class.new(WorkItem, issue.id, "project_#{project.id}") }
 
     it 'preloads database records to avoid N+1 queries' do
@@ -71,16 +71,15 @@
         database_records = described_class.preload_indexing_data(refs).map(&:database_record)
       end.not_to exceed_query_limit(control)
 
-      expect(database_records[0]).to eq(issue)
-      expect(database_records[2]).to eq(issue2)
+      expect(database_records[0].id).to eq(issue.id)
+      expect(database_records[2].id).to eq(issue2.id)
     end
 
     it 'calls preload in batches not to overload the database' do
       stub_const('Search::Elastic::Concerns::DatabaseClassReference::BATCH_SIZE', 1)
       refs = [embedding_ref, embedding_ref2]
 
-      expect(Issue).to receive(:preload_indexing_data).and_call_original.once
-      expect(WorkItem).to receive(:preload_indexing_data).and_call_original.once
+      expect(WorkItem).to receive(:preload_indexing_data).and_call_original.twice
 
       described_class.preload_indexing_data(refs)
     end
@@ -188,14 +187,8 @@
   end
 
   describe '#index_name' do
-    it 'is equal to proxy index name' do
-      expect(embedding_ref.index_name).to eq('gitlab-test-issues')
-    end
-
-    context 'if type class exists' do
-      it 'is equal type class index name' do
-        expect(work_item_embedding_ref.index_name).to eq('gitlab-test-work_items')
-      end
+    it 'is equal type class index name' do
+      expect(embedding_ref.index_name).to eq('gitlab-test-work_items')
     end
   end
 end
diff --git a/ee/spec/services/search/elastic/cluster_reindexing_service_spec.rb b/ee/spec/services/search/elastic/cluster_reindexing_service_spec.rb
index 65b6396b88759c5de8421f2c7b66fff86093004e..1d7da0576d855634e3866622259eeaf47a76e946 100644
--- a/ee/spec/services/search/elastic/cluster_reindexing_service_spec.rb
+++ b/ee/spec/services/search/elastic/cluster_reindexing_service_spec.rb
@@ -89,9 +89,9 @@
   end
 
   context 'for state: indexing_paused' do
-    let(:issues_alias) { Issue.__elasticsearch__.index_name }
-    let(:issues_old_index_name) { "#{issues_alias}-1" }
-    let(:issues_new_index_name) { "#{issues_alias}-reindex" }
+    let(:notes_alias) { Note.__elasticsearch__.index_name }
+    let(:notes_old_index_name) { "#{notes_alias}-1" }
+    let(:notes_new_index_name) { "#{notes_alias}-reindex" }
 
     let(:main_alias) { Repository.__elasticsearch__.index_name }
     let(:main_old_index_name) { "#{main_alias}-1" }
@@ -103,14 +103,14 @@
       before do
         allow(helper).to receive(:target_index_names) { |options| { "#{options[:target]}-1" => true } }
         allow(helper).to receive_messages(
-          create_standalone_indices: { issues_new_index_name => issues_alias },
+          create_standalone_indices: { notes_new_index_name => notes_alias },
           create_empty_index: { main_new_index_name => main_alias }
         )
         allow(helper).to receive(:reindex) { |options| "#{options[:to]}_task_id" }
         allow(helper).to receive(:get_settings) do |options|
           number_of_shards = case options[:index_name]
                              when main_old_index_name then 10
-                             when issues_old_index_name then 3
+                             when notes_old_index_name then 1
                              else
                                1
                              end
@@ -133,13 +133,13 @@
         expect(slice_1.elastic_task).to eq("#{main_new_index_name}_task_id")
         expect(slice_1.elastic_slice).to eq(0)
 
-        subtask_2 = subtasks.find { |subtask| subtask.alias_name == issues_alias }
+        subtask_2 = subtasks.find { |subtask| subtask.alias_name == notes_alias }
         slice_2 = subtask_2.slices.last
-        expect(subtask_2.index_name_to).to eq(issues_new_index_name)
-        expect(subtask_2.slices.count).to eq(6)
-        expect(slice_2.elastic_max_slice).to eq(6)
-        expect(slice_2.elastic_task).to eq("#{issues_new_index_name}_task_id")
-        expect(slice_2.elastic_slice).to eq(5)
+        expect(subtask_2.index_name_to).to eq(notes_new_index_name)
+        expect(subtask_2.slices.count).to eq(2)
+        expect(slice_2.elastic_max_slice).to eq(2)
+        expect(slice_2.elastic_task).to eq("#{notes_new_index_name}_task_id")
+        expect(slice_2.elastic_slice).to eq(1)
       end
     end
 
@@ -150,8 +150,8 @@
         allow(helper).to receive(:target_index_names) { |options| { "#{options[:target]}-1" => true } }
       end
 
-      context 'when targets set to issue and repository' do
-        let(:targets) { %w[Issue Repository] }
+      context 'when targets set to note and repository' do
+        let(:targets) { %w[Note Repository] }
 
         it 'creates multiple indices' do
           expect(helper).to receive(:create_empty_index).and_return(main_new_index_name => main_alias)
@@ -159,8 +159,8 @@
           is_expected.to receive(:launch_subtasks).with(
             array_including(
               {
-                alias_name: issues_alias,
-                index_name_from: issues_old_index_name,
+                alias_name: notes_alias,
+                index_name_from: notes_old_index_name,
                 index_name_to: anything
               },
               {
@@ -176,15 +176,15 @@
       end
 
       context 'when targets do not include repository' do
-        let(:targets) { %w[Issue] }
+        let(:targets) { %w[Note] }
 
         it 'does not create the main index' do
           expect(helper).not_to receive(:create_empty_index)
           is_expected.to receive(:launch_subtasks).with(
             array_including(
               hash_including(
-                alias_name: issues_alias,
-                index_name_from: issues_old_index_name,
+                alias_name: notes_alias,
+                index_name_from: notes_old_index_name,
                 index_name_to: anything
               )
             ))
diff --git a/ee/spec/services/search/rake_task_executor_service_spec.rb b/ee/spec/services/search/rake_task_executor_service_spec.rb
index 024a3b7c6649fdd46da93d6122de31f926195599..b23de294105f4e9b4e93ecee8a231c87148f02b6 100644
--- a/ee/spec/services/search/rake_task_executor_service_spec.rb
+++ b/ee/spec/services/search/rake_task_executor_service_spec.rb
@@ -256,7 +256,8 @@
   end
 
   describe '#estimate_shard_sizes' do
-    let(:db_counts) { [400, 1500, 10_000_000, 50_000_000, 100_000_000, 4_000, 5_000, 5_000] }
+    # DB_CLASSES = [Note, MergeRequest, User, Project, WorkItem, Vulnerability]
+    let(:db_counts) { [400, 1500, 10_000_000, 4_000, 5_000, 6_000] }
 
     before do
       allow(logger).to receive(:info)
@@ -269,46 +270,25 @@
     end
 
     it 'outputs shard size estimates' do
-      expected_work_items = <<~ESTIMATE
-        - gitlab-test-work_items:
-          recommended shards: 5
-          recommended replicas: 1
-          document count: 5,000
-      ESTIMATE
-
-      expected_issues = <<~ESTIMATE
-        - gitlab-test-issues:
-          recommended shards: 5
-          recommended replicas: 1
-          document count: 400
-      ESTIMATE
-
       expected_notes = <<~ESTIMATE.chomp
         - gitlab-test-notes:
           recommended shards: 5
           recommended replicas: 1
-          document count: 1,500
+          document count: 400
       ESTIMATE
 
       expected_merge_requests = <<~ESTIMATE.chomp
         - gitlab-test-merge_requests:
           recommended shards: 5
           recommended replicas: 1
-          document count: 10,000,000
-      ESTIMATE
-
-      expected_epics = <<~ESTIMATE.chomp
-        - gitlab-test-epics:
-          recommended shards: 10
-          recommended replicas: 1
-          document count: 50,000,000
+          document count: 1,500
       ESTIMATE
 
       expected_users = <<~ESTIMATE.chomp
         - gitlab-test-users:
-          recommended shards: 20
+          recommended shards: 5
           recommended replicas: 1
-          document count: 100,000,000
+          document count: 10,000,000
       ESTIMATE
 
       expected_projects = <<~ESTIMATE.chomp
@@ -318,11 +298,18 @@
           document count: 4,000
       ESTIMATE
 
+      expected_work_items = <<~ESTIMATE.chomp
+        - gitlab-test-work_items:
+          recommended shards: 5
+          recommended replicas: 1
+          document count: 5,000
+      ESTIMATE
+
       expected_vulnerabilities = <<~ESTIMATE.chomp
         - gitlab-test-vulnerabilities:
           recommended shards: 5
           recommended replicas: 1
-          document count: 5,000
+          document count: 6,000
       ESTIMATE
 
       expected_main_index = <<~ESTIMATE.chomp
@@ -343,10 +330,8 @@
           recommended replicas: 1
       ESTIMATE
 
-      expect(logger).to receive(:info).with(/#{expected_issues}/)
       expect(logger).to receive(:info).with(/#{expected_notes}/)
       expect(logger).to receive(:info).with(/#{expected_merge_requests}/)
-      expect(logger).to receive(:info).with(/#{expected_epics}/)
       expect(logger).to receive(:info).with(/#{expected_users}/)
       expect(logger).to receive(:info).with(/#{expected_projects}/)
       expect(logger).to receive(:info).with(/#{expected_work_items}/)
@@ -714,51 +699,6 @@
     end
   end
 
-  describe '#index_epics' do
-    let!(:epic) { create(:epic) }
-
-    it 'calls maintain_indexed_namespace_associations for groups' do
-      expect(logger).to receive(:info).with(/Indexing epics/).twice
-      expect(Elastic::ProcessInitialBookkeepingService).to receive(:maintain_indexed_namespace_associations!)
-        .with(epic.group, associations_to_index: [:epics])
-
-      service.execute(:index_epics)
-    end
-
-    it 'avoids N+1 queries', :use_sql_query_cache do
-      control = ActiveRecord::QueryRecorder.new(skip_cached: false) { service.execute(:index_epics) }
-
-      create_list(:epic, 3)
-
-      expect(Elastic::ProcessInitialBookkeepingService).to receive(:maintain_indexed_namespace_associations!)
-
-      expect { service.execute(:index_epics) }.to issue_same_number_of_queries_as(control)
-    end
-
-    context 'with limited indexing enabled' do
-      let!(:group1) { create(:group) }
-      let!(:group2) { create(:group) }
-      let!(:group3) { create(:group) }
-
-      before do
-        create(:elasticsearch_indexed_namespace, namespace: group1)
-        create(:elasticsearch_indexed_namespace, namespace: group3)
-
-        stub_ee_application_setting(elasticsearch_limit_indexing: true)
-      end
-
-      it 'does not call maintain_indexed_namespace_associations for groups that should not be indexed' do
-        expect(logger).to receive(:info).with(/Indexing epics/).twice
-        expect(Elastic::ProcessBookkeepingService).to receive(:maintain_indexed_namespace_associations!) do |*params|
-          expect(params.count).to eq(3)
-          expect([params[0], params[1]]).to contain_exactly(group1, group3)
-          expect(params[2]).to eq(associations_to_index: [:epics])
-        end
-        service.execute(:index_epics)
-      end
-    end
-  end
-
   describe '#projects_not_indexed' do
     let_it_be(:project) { create(:project, :repository) }
     let_it_be(:project_no_repository) { create(:project) }
@@ -898,7 +838,7 @@
     end
 
     it 'calls other tasks in order' do
-      expect(service).to receive(:index_epics).ordered
+      expect(service).to receive(:index_work_items).ordered
       expect(service).to receive(:index_group_wikis).ordered
 
       index_group_entities
diff --git a/ee/spec/tasks/gitlab/elastic_rake_spec.rb b/ee/spec/tasks/gitlab/elastic_rake_spec.rb
index ef41ee2d363b085ca4f8f954b2628647c3708c4b..337639032ca2e66837e02779c171bf284b488c2c 100644
--- a/ee/spec/tasks/gitlab/elastic_rake_spec.rb
+++ b/ee/spec/tasks/gitlab/elastic_rake_spec.rb
@@ -49,8 +49,12 @@
     include_examples 'rake task executor task', :index_users
   end
 
-  describe 'gitlab:elastic:index_epics' do
-    include_examples 'rake task executor task', :index_epics
+  describe 'gitlab:elastic:index_work_items' do
+    include_examples 'rake task executor task', :index_work_items
+  end
+
+  describe 'gitlab:elastic:index_namespaces' do
+    include_examples 'rake task executor task', :index_namespaces
   end
 
   describe 'gitlab:elastic:index_group_wikis' do