diff --git a/app/controllers/admin/users_controller.rb b/app/controllers/admin/users_controller.rb
index 6b8a0fca4..c1194709f 100644
--- a/app/controllers/admin/users_controller.rb
+++ b/app/controllers/admin/users_controller.rb
@@ -54,7 +54,7 @@ class Admin::UsersController < Admin::AdminController
     @user.suspended_at = DateTime.now
     @user.save!
     StaffActionLogger.new(current_user).log_user_suspend(@user, params[:reason])
-    DiscourseBus.publish "/logout", @user.id, user_ids: [@user.id]
+    MessageBus.publish "/logout", @user.id, user_ids: [@user.id]
     render nothing: true
   end
 
@@ -71,7 +71,7 @@ class Admin::UsersController < Admin::AdminController
     if @user
       @user.auth_token = nil
       @user.save!
-      DiscourseBus.publish "/logout", @user.id, user_ids: [@user.id]
+      MessageBus.publish "/logout", @user.id, user_ids: [@user.id]
       render json: success_json
     else
       render json: {error: I18n.t('admin_js.admin.users.id_not_found')}, status: 404
@@ -350,7 +350,7 @@ class Admin::UsersController < Admin::AdminController
     end
 
     def refresh_browser(user)
-      DiscourseBus.publish "/file-change", ["refresh"], user_ids: [user.id]
+      MessageBus.publish "/file-change", ["refresh"], user_ids: [user.id]
     end
 
 end
diff --git a/app/models/category.rb b/app/models/category.rb
index de46c3e19..bfaf2f001 100644
--- a/app/models/category.rb
+++ b/app/models/category.rb
@@ -222,7 +222,7 @@ SQL
   end
 
   def publish_categories_list
-    DiscourseBus.publish('/categories', {categories: ActiveModel::ArraySerializer.new(Category.latest).as_json})
+    MessageBus.publish('/categories', {categories: ActiveModel::ArraySerializer.new(Category.latest).as_json})
   end
 
   def parent_category_validator
diff --git a/app/models/color_scheme.rb b/app/models/color_scheme.rb
index a575db8fd..d4a1b02de 100644
--- a/app/models/color_scheme.rb
+++ b/app/models/color_scheme.rb
@@ -97,7 +97,7 @@ class ColorScheme < ActiveRecord::Base
   end
 
   def publish_discourse_stylesheet
-    DiscourseBus.publish("/discourse_stylesheet", self.name)
+    MessageBus.publish("/discourse_stylesheet", self.name)
     DiscourseStylesheets.cache.clear
   end
 
diff --git a/app/models/post.rb b/app/models/post.rb
index 9ddf014ea..281b6a3d4 100644
--- a/app/models/post.rb
+++ b/app/models/post.rb
@@ -97,7 +97,7 @@ class Post < ActiveRecord::Base
     # special failsafe for posts missing topics
     # consistency checks should fix, but message
     # is safe to skip
-    DiscourseBus.publish("/topic/#{topic_id}", {
+    MessageBus.publish("/topic/#{topic_id}", {
         id: id,
         post_number: post_number,
         updated_at: Time.now,
diff --git a/app/models/post_action.rb b/app/models/post_action.rb
index 72722d4e1..5fc133012 100644
--- a/app/models/post_action.rb
+++ b/app/models/post_action.rb
@@ -56,7 +56,7 @@ class PostAction < ActiveRecord::Base
 
     $redis.set('posts_flagged_count', posts_flagged_count)
     user_ids = User.staff.pluck(:id)
-    DiscourseBus.publish('/flagged_counts', { total: posts_flagged_count }, { user_ids: user_ids })
+    MessageBus.publish('/flagged_counts', { total: posts_flagged_count }, { user_ids: user_ids })
   end
 
   def self.flagged_posts_count
diff --git a/app/models/queued_post.rb b/app/models/queued_post.rb
index 5f3fad170..39c51a354 100644
--- a/app/models/queued_post.rb
+++ b/app/models/queued_post.rb
@@ -42,7 +42,7 @@ class QueuedPost < ActiveRecord::Base
 
   def self.broadcast_new!
     msg = { post_queue_new_count: QueuedPost.new_count }
-    DiscourseBus.publish('/queue_counts', msg, user_ids: User.staff.pluck(:id))
+    MessageBus.publish('/queue_counts', msg, user_ids: User.staff.pluck(:id))
   end
 
   def reject!(rejected_by)
diff --git a/app/models/site_customization.rb b/app/models/site_customization.rb
index aff6ae159..790f15ca4 100644
--- a/app/models/site_customization.rb
+++ b/app/models/site_customization.rb
@@ -34,11 +34,11 @@ class SiteCustomization < ActiveRecord::Base
   after_save do
     remove_from_cache!
     if stylesheet_changed? || mobile_stylesheet_changed?
-      DiscourseBus.publish "/file-change/#{key}", SecureRandom.hex
-      DiscourseBus.publish "/file-change/#{SiteCustomization::ENABLED_KEY}", SecureRandom.hex
+      MessageBus.publish "/file-change/#{key}", SecureRandom.hex
+      MessageBus.publish "/file-change/#{SiteCustomization::ENABLED_KEY}", SecureRandom.hex
     end
-    DiscourseBus.publish "/header-change/#{key}", header if header_changed?
-    DiscourseBus.publish "/footer-change/#{key}", footer if footer_changed?
+    MessageBus.publish "/header-change/#{key}", header if header_changed?
+    MessageBus.publish "/footer-change/#{key}", footer if footer_changed?
     DiscourseStylesheets.cache.clear
   end
 
@@ -109,7 +109,7 @@ class SiteCustomization < ActiveRecord::Base
   end
 
   def self.remove_from_cache!(key, broadcast = true)
-    DiscourseBus.publish('/site_customization', key: key) if broadcast
+    MessageBus.publish('/site_customization', key: key) if broadcast
     clear_cache!
   end
 
diff --git a/app/models/topic.rb b/app/models/topic.rb
index 899246f8c..8dc8df8bb 100644
--- a/app/models/topic.rb
+++ b/app/models/topic.rb
@@ -641,7 +641,7 @@ class Topic < ActiveRecord::Base
     self.add_moderator_post(user, I18n.t("archetypes.banner.message.make"))
     self.save
 
-    DiscourseBus.publish('/site/banner', banner)
+    MessageBus.publish('/site/banner', banner)
   end
 
   def remove_banner!(user)
@@ -649,7 +649,7 @@ class Topic < ActiveRecord::Base
     self.add_moderator_post(user, I18n.t("archetypes.banner.message.remove"))
     self.save
 
-    DiscourseBus.publish('/site/banner', nil)
+    MessageBus.publish('/site/banner', nil)
   end
 
   def banner
diff --git a/app/models/topic_tracking_state.rb b/app/models/topic_tracking_state.rb
index 61ca7506e..0bf3fa709 100644
--- a/app/models/topic_tracking_state.rb
+++ b/app/models/topic_tracking_state.rb
@@ -33,7 +33,7 @@ class TopicTrackingState
 
     group_ids = topic.category && topic.category.secure_group_ids
 
-    DiscourseBus.publish("/new", message.as_json, group_ids: group_ids)
+    MessageBus.publish("/new", message.as_json, group_ids: group_ids)
     publish_read(topic.id, 1, topic.user_id)
   end
 
@@ -51,7 +51,7 @@ class TopicTrackingState
     }
 
     group_ids = topic.category && topic.category.secure_group_ids
-    DiscourseBus.publish("/latest", message.as_json, group_ids: group_ids)
+    MessageBus.publish("/latest", message.as_json, group_ids: group_ids)
   end
 
   def self.publish_unread(post)
@@ -77,7 +77,7 @@ class TopicTrackingState
         }
       }
 
-      DiscourseBus.publish("/unread/#{tu.user_id}", message.as_json, group_ids: group_ids)
+      MessageBus.publish("/unread/#{tu.user_id}", message.as_json, group_ids: group_ids)
     end
 
   end
@@ -97,7 +97,7 @@ class TopicTrackingState
       }
     }
 
-    DiscourseBus.publish("/unread/#{user_id}", message.as_json, user_ids: [user_id])
+    MessageBus.publish("/unread/#{user_id}", message.as_json, user_ids: [user_id])
 
   end
 
diff --git a/app/models/topic_user.rb b/app/models/topic_user.rb
index 87df2c633..2611039f3 100644
--- a/app/models/topic_user.rb
+++ b/app/models/topic_user.rb
@@ -40,7 +40,7 @@ class TopicUser < ActiveRecord::Base
           notifications_reason_id: reason
         )
 
-        DiscourseBus.publish("/topic/#{topic_id}", {
+        MessageBus.publish("/topic/#{topic_id}", {
           notification_level_change: notification_levels[:tracking],
           notifications_reason_id: reason
         }, user_ids: [user_id])
@@ -113,7 +113,7 @@ class TopicUser < ActiveRecord::Base
       end
 
       if attrs[:notification_level]
-        DiscourseBus.publish("/topic/#{topic_id}",
+        MessageBus.publish("/topic/#{topic_id}",
                          {notification_level_change: attrs[:notification_level]}, user_ids: [user_id])
       end
 
@@ -196,7 +196,7 @@ class TopicUser < ActiveRecord::Base
         end
 
         if before != after
-          DiscourseBus.publish("/topic/#{topic_id}", {notification_level_change: after}, user_ids: [user.id])
+          MessageBus.publish("/topic/#{topic_id}", {notification_level_change: after}, user_ids: [user.id])
         end
       end
 
@@ -219,7 +219,7 @@ class TopicUser < ActiveRecord::Base
                                    WHERE ftu.user_id = :user_id and ftu.topic_id = :topic_id)",
                   args)
 
-        DiscourseBus.publish("/topic/#{topic_id}", {notification_level_change: args[:new_status]}, user_ids: [user.id])
+        MessageBus.publish("/topic/#{topic_id}", {notification_level_change: args[:new_status]}, user_ids: [user.id])
       end
     end
 
diff --git a/app/models/user.rb b/app/models/user.rb
index 19431c099..0660f0bc0 100644
--- a/app/models/user.rb
+++ b/app/models/user.rb
@@ -206,7 +206,7 @@ class User < ActiveRecord::Base
   # tricky, we need our bus to be subscribed from the right spot
   def sync_notification_channel_position
     @unread_notifications_by_type = nil
-    self.notification_channel_position = DiscourseBus.last_id("/notification/#{id}")
+    self.notification_channel_position = MessageBus.last_id("/notification/#{id}")
   end
 
   def invited_by
@@ -298,7 +298,7 @@ class User < ActiveRecord::Base
   end
 
   def publish_notifications_state
-    DiscourseBus.publish("/notification/#{id}",
+    MessageBus.publish("/notification/#{id}",
                        {unread_notifications: unread_notifications,
                         unread_private_messages: unread_private_messages,
                         total_unread_notifications: total_unread_notifications},
diff --git a/app/models/user_action.rb b/app/models/user_action.rb
index 11926badf..0e979991c 100644
--- a/app/models/user_action.rb
+++ b/app/models/user_action.rb
@@ -224,7 +224,7 @@ SQL
         end
 
         if action.user
-          DiscourseBus.publish("/users/#{action.user.username.downcase}", action.id, user_ids: [user_id], group_ids: group_ids)
+          MessageBus.publish("/users/#{action.user.username.downcase}", action.id, user_ids: [user_id], group_ids: group_ids)
         end
 
         action
@@ -240,7 +240,7 @@ SQL
     require_parameters(hash, :action_type, :user_id, :acting_user_id, :target_topic_id, :target_post_id)
     if action = UserAction.find_by(hash.except(:created_at))
       action.destroy
-      DiscourseBus.publish("/user/#{hash[:user_id]}", {user_action_id: action.id, remove: true})
+      MessageBus.publish("/user/#{hash[:user_id]}", {user_action_id: action.id, remove: true})
     end
 
     update_like_count(hash[:user_id], hash[:action_type], -1)
diff --git a/app/services/user_destroyer.rb b/app/services/user_destroyer.rb
index a6dd4da49..2b70d181c 100644
--- a/app/services/user_destroyer.rb
+++ b/app/services/user_destroyer.rb
@@ -80,7 +80,7 @@ class UserDestroyer
           end
 
           StaffActionLogger.new(@actor == user ? Discourse.system_user : @actor).log_user_deletion(user, opts.slice(:context))
-          DiscourseBus.publish "/file-change", ["refresh"], user_ids: [user.id]
+          MessageBus.publish "/file-change", ["refresh"], user_ids: [user.id]
         end
       end
     end
diff --git a/config/initializers/04-discourse_bus.rb b/config/initializers/04-discourse_bus.rb
deleted file mode 100644
index 57b44c675..000000000
--- a/config/initializers/04-discourse_bus.rb
+++ /dev/null
@@ -1,3 +0,0 @@
-require_dependency 'discourse_bus'
-
-DiscourseBus.start!
diff --git a/config/initializers/04-message_bus.rb b/config/initializers/04-message_bus.rb
new file mode 100644
index 000000000..7ada7b9ff
--- /dev/null
+++ b/config/initializers/04-message_bus.rb
@@ -0,0 +1,47 @@
+MessageBus.site_id_lookup do
+  RailsMultisite::ConnectionManagement.current_db
+end
+
+MessageBus.extra_response_headers_lookup do |env|
+  {
+    "Access-Control-Allow-Origin" => Discourse.base_url_no_prefix,
+    "Access-Control-Allow-Methods" => "GET, POST",
+    "Access-Control-Allow-Headers" => "X-SILENCE-LOGGER, X-Shared-Session-Key"
+  }
+end
+
+MessageBus.user_id_lookup do |env|
+  user = CurrentUser.lookup_from_env(env)
+  user.id if user
+end
+
+MessageBus.group_ids_lookup do |env|
+  user = CurrentUser.lookup_from_env(env)
+  user.groups.select('groups.id').map{|g| g.id} if user
+end
+
+MessageBus.on_connect do |site_id|
+  RailsMultisite::ConnectionManagement.establish_connection(db: site_id)
+end
+
+MessageBus.on_disconnect do |site_id|
+  ActiveRecord::Base.connection_handler.clear_active_connections!
+end
+
+# Point at our redis
+MessageBus.redis_config = YAML.load(ERB.new(File.new("#{Rails.root}/config/redis.yml").read).result)[Rails.env].symbolize_keys
+
+MessageBus.long_polling_enabled = SiteSetting.enable_long_polling
+MessageBus.long_polling_interval = SiteSetting.long_polling_interval
+
+MessageBus.is_admin_lookup do |env|
+  user = CurrentUser.lookup_from_env(env)
+  if user && user.admin
+    true
+  else
+    false
+  end
+end
+
+MessageBus.cache_assets = !Rails.env.development?
+MessageBus.enable_diagnostics
diff --git a/lib/auth/default_current_user_provider.rb b/lib/auth/default_current_user_provider.rb
index 19a3084bb..1e5cec773 100644
--- a/lib/auth/default_current_user_provider.rb
+++ b/lib/auth/default_current_user_provider.rb
@@ -85,7 +85,7 @@ class Auth::DefaultCurrentUserProvider
     if SiteSetting.log_out_strict && (user = current_user)
       user.auth_token = nil
       user.save!
-      DiscourseBus.publish "/logout", user.id, user_ids: [user.id]
+      MessageBus.publish "/logout", user.id, user_ids: [user.id]
     end
     cookies[TOKEN_COOKIE] = nil
   end
diff --git a/lib/backup_restore/backup_restore.rb b/lib/backup_restore/backup_restore.rb
index c419e8299..c917be31b 100644
--- a/lib/backup_restore/backup_restore.rb
+++ b/lib/backup_restore/backup_restore.rb
@@ -62,7 +62,7 @@ module BackupRestore
 
   def self.logs
     id = start_logs_message_id
-    DiscourseBus.backlog(LOGS_CHANNEL, id).map { |m| m.data }
+    MessageBus.backlog(LOGS_CHANNEL, id).map { |m| m.data }
   end
 
   def self.current_version
@@ -142,7 +142,7 @@ module BackupRestore
   end
 
   def self.save_start_logs_message_id
-    id = DiscourseBus.last_id(LOGS_CHANNEL)
+    id = MessageBus.last_id(LOGS_CHANNEL)
     $redis.set(start_logs_message_id_key, id)
   end
 
diff --git a/lib/backup_restore/backuper.rb b/lib/backup_restore/backuper.rb
index 3c5106857..a1eff0221 100644
--- a/lib/backup_restore/backuper.rb
+++ b/lib/backup_restore/backuper.rb
@@ -336,7 +336,7 @@ module BackupRestore
     def publish_log(message, timestamp)
       return unless @publish_to_message_bus
       data = { timestamp: timestamp, operation: "backup", message: message }
-      DiscourseBus.publish(BackupRestore::LOGS_CHANNEL, data, user_ids: [@user_id])
+      MessageBus.publish(BackupRestore::LOGS_CHANNEL, data, user_ids: [@user_id])
     end
 
     def save_log(message, timestamp)
diff --git a/lib/backup_restore/restorer.rb b/lib/backup_restore/restorer.rb
index 0599a2c03..bccd2e607 100644
--- a/lib/backup_restore/restorer.rb
+++ b/lib/backup_restore/restorer.rb
@@ -354,7 +354,7 @@ module BackupRestore
     def publish_log(message, timestamp)
       return unless @publish_to_message_bus
       data = { timestamp: timestamp, operation: "restore", message: message }
-      DiscourseBus.publish(BackupRestore::LOGS_CHANNEL, data, user_ids: [@user_id])
+      MessageBus.publish(BackupRestore::LOGS_CHANNEL, data, user_ids: [@user_id])
     end
 
     def save_log(message, timestamp)
diff --git a/lib/discourse.rb b/lib/discourse.rb
index 44d708e2a..653703779 100644
--- a/lib/discourse.rb
+++ b/lib/discourse.rb
@@ -119,10 +119,10 @@ module Discourse
       digest = Digest::MD5.hexdigest(ActionView::Base.assets_manifest.assets.values.sort.join)
 
       channel = "/global/asset-version"
-      message = DiscourseBus.last_message(channel)
+      message = MessageBus.last_message(channel)
 
       unless message && message.data == digest
-        DiscourseBus.publish channel, digest
+        MessageBus.publish channel, digest
       end
       digest
     end
@@ -193,7 +193,7 @@ module Discourse
 
   def self.enable_readonly_mode
     $redis.set(readonly_mode_key, 1)
-    DiscourseBus.publish(readonly_channel, true)
+    MessageBus.publish(readonly_channel, true)
     keep_readonly_mode
     true
   end
@@ -210,7 +210,7 @@ module Discourse
 
   def self.disable_readonly_mode
     $redis.del(readonly_mode_key)
-    DiscourseBus.publish(readonly_channel, false)
+    MessageBus.publish(readonly_channel, false)
     true
   end
 
@@ -221,9 +221,9 @@ module Discourse
   def self.request_refresh!
     # Causes refresh on next click for all clients
     #
-    # This is better than `DiscourseBus.publish "/file-change", ["refresh"]` because
+    # This is better than `MessageBus.publish "/file-change", ["refresh"]` because
     # it spreads the refreshes out over a time period
-    DiscourseBus.publish '/global/asset-version', 'clobber'
+    MessageBus.publish '/global/asset-version', 'clobber'
   end
 
   def self.git_version
@@ -298,7 +298,7 @@ module Discourse
   def self.after_fork
     current_db = RailsMultisite::ConnectionManagement.current_db
     RailsMultisite::ConnectionManagement.establish_connection(db: current_db)
-    DiscourseBus.after_fork
+    MessageBus.after_fork
     SiteSetting.after_fork
     $redis.client.reconnect
     Rails.cache.reconnect
diff --git a/lib/discourse_bus.rb b/lib/discourse_bus.rb
deleted file mode 100644
index cb39db0df..000000000
--- a/lib/discourse_bus.rb
+++ /dev/null
@@ -1,73 +0,0 @@
-# Proxies MessageBus and noops READONLY errors.
-module DiscourseBus
-
-  def self.start!
-    MessageBus.site_id_lookup do
-      RailsMultisite::ConnectionManagement.current_db
-    end
-
-    MessageBus.extra_response_headers_lookup do |env|
-      {
-        "Access-Control-Allow-Origin" => Discourse.base_url_no_prefix,
-        "Access-Control-Allow-Methods" => "GET, POST",
-        "Access-Control-Allow-Headers" => "X-SILENCE-LOGGER, X-Shared-Session-Key"
-      }
-    end
-
-    MessageBus.user_id_lookup do |env|
-      user = CurrentUser.lookup_from_env(env)
-      user.id if user
-    end
-
-    MessageBus.group_ids_lookup do |env|
-      user = CurrentUser.lookup_from_env(env)
-      user.groups.select('groups.id').map{|g| g.id} if user
-    end
-
-    MessageBus.on_connect do |site_id|
-      RailsMultisite::ConnectionManagement.establish_connection(db: site_id)
-    end
-
-    MessageBus.on_disconnect do |site_id|
-      ActiveRecord::Base.connection_handler.clear_active_connections!
-    end
-
-    # Point at our redis
-    MessageBus.redis_config = YAML.load(ERB.new(File.new("#{Rails.root}/config/redis.yml").read).result)[Rails.env].symbolize_keys
-
-    MessageBus.long_polling_enabled = SiteSetting.enable_long_polling
-    MessageBus.long_polling_interval = SiteSetting.long_polling_interval
-
-    MessageBus.is_admin_lookup do |env|
-      user = CurrentUser.lookup_from_env(env)
-      if user && user.admin
-        true
-      else
-        false
-      end
-    end
-
-    MessageBus.cache_assets = !Rails.env.development?
-    MessageBus.enable_diagnostics
-  end
-
-  def self.proxy_readonly(*methods)
-    methods.each do |name|
-      define_singleton_method(name) do |*args, &block|
-        DiscourseRedis.ignore_readonly { MessageBus.send(name, *args, &block) }
-      end
-    end
-  end
-
-  proxy_readonly :publish,
-                 :subscribe,
-                 :unsubscribe,
-                 :last_id,
-                 :last_message,
-                 :backlog,
-                 :after_fork,
-                 :on_connect,
-                 :on_disconnect,
-                 :track_publish
-
-end
diff --git a/lib/distributed_cache.rb b/lib/distributed_cache.rb
index 44cd2744f..28307e375 100644
--- a/lib/distributed_cache.rb
+++ b/lib/distributed_cache.rb
@@ -51,7 +51,7 @@ class DistributedCache
     return if @subscribed
     @lock.synchronize do
       return if @subscribed
-      DiscourseBus.subscribe(channel_name) do |message|
+      MessageBus.subscribe(channel_name) do |message|
         @lock.synchronize do
           process_message(message)
         end
@@ -63,7 +63,7 @@ class DistributedCache
   def self.publish(hash, message)
     message[:origin] = hash.identity
     message[:hash_key] = hash.key
-    DiscourseBus.publish(channel_name, message, { user_ids: [-1] })
+    MessageBus.publish(channel_name, message, { user_ids: [-1] })
   end
 
   def self.set(hash, key, value)
diff --git a/lib/message_bus_diags.rb b/lib/message_bus_diags.rb
index 1ef448bf7..3d7f795dc 100644
--- a/lib/message_bus_diags.rb
+++ b/lib/message_bus_diags.rb
@@ -11,7 +11,7 @@ class MessageBusDiags
   end
 
   def self.establish_peer_names
-    DiscourseBus.publish "/server-name", {channel: "/server-name-reply/#{my_id}"}
+    MessageBus.publish "/server-name", {channel: "/server-name-reply/#{my_id}"}
   end
 
   def self.seen_hosts
@@ -20,12 +20,12 @@ class MessageBusDiags
 
   unless @subscribed
 
-    DiscourseBus.subscribe "/server-name-reply/#{my_id}" do |msg|
+    MessageBus.subscribe "/server-name-reply/#{my_id}" do |msg|
       MessageBusDiags.seen_host(msg.data)
     end
 
-    DiscourseBus.subscribe "/server-name" do |msg|
-      DiscourseBus.publish msg.data["channel"], MessageBusDiags.my_id
+    MessageBus.subscribe "/server-name" do |msg|
+      MessageBus.publish msg.data["channel"], MessageBusDiags.my_id
     end
     @subscribed = true
   end
diff --git a/lib/site_setting_extension.rb b/lib/site_setting_extension.rb
index 22ef80961..456f94d33 100644
--- a/lib/site_setting_extension.rb
+++ b/lib/site_setting_extension.rb
@@ -221,7 +221,7 @@ module SiteSettingExtension
 
   def ensure_listen_for_changes
     unless @subscribed
-      DiscourseBus.subscribe("/site_settings") do |message|
+      MessageBus.subscribe("/site_settings") do |message|
         process_message(message)
       end
       @subscribed = true
@@ -233,10 +233,10 @@ module SiteSettingExtension
     if data["process"] != process_id
       begin
         @last_message_processed = message.global_id
-        DiscourseBus.on_connect.call(message.site_id)
+        MessageBus.on_connect.call(message.site_id)
         refresh!
       ensure
-        DiscourseBus.on_disconnect.call(message.site_id)
+        MessageBus.on_disconnect.call(message.site_id)
       end
     end
   end
@@ -294,7 +294,7 @@ module SiteSettingExtension
   end
 
   def notify_changed!
-    DiscourseBus.publish('/site_settings', {process: process_id})
+    MessageBus.publish('/site_settings', {process: process_id})
   end
 
   def has_setting?(name)
diff --git a/plugins/poll/plugin.rb b/plugins/poll/plugin.rb
index c66e3cc7d..853e39cde 100644
--- a/plugins/poll/plugin.rb
+++ b/plugins/poll/plugin.rb
@@ -70,7 +70,7 @@ after_initialize do
           post.custom_fields["#{VOTES_CUSTOM_FIELD}-#{user_id}"] = votes
           post.save_custom_fields(true)
 
-          DiscourseBus.publish("/polls/#{post_id}", { polls: polls })
+          MessageBus.publish("/polls/#{post_id}", { polls: polls })
 
           return [poll, options]
         end
@@ -100,7 +100,7 @@ after_initialize do
 
           post.save_custom_fields(true)
 
-          DiscourseBus.publish("/polls/#{post_id}", { polls: polls })
+          MessageBus.publish("/polls/#{post_id}", { polls: polls })
 
           polls[poll_name]
         end
@@ -299,7 +299,7 @@ after_initialize do
           post.save_custom_fields(true)
 
           # publish the changes
-          DiscourseBus.publish("/polls/#{post.id}", { polls: polls })
+          MessageBus.publish("/polls/#{post.id}", { polls: polls })
         end
       end
     else
@@ -321,7 +321,7 @@ after_initialize do
   # tells the front-end we have a poll for that post
   on(:post_created) do |post|
     next if post.is_first_post? || post.custom_fields[POLLS_CUSTOM_FIELD].blank?
-    DiscourseBus.publish("/polls", { post_id: post.id })
+    MessageBus.publish("/polls", { post_id: post.id })
   end
 
   add_to_serializer(:post, :polls, false) { post_custom_fields[POLLS_CUSTOM_FIELD] }
diff --git a/plugins/poll/spec/controllers/polls_controller_spec.rb b/plugins/poll/spec/controllers/polls_controller_spec.rb
index 3e79ab7cd..ab9081285 100644
--- a/plugins/poll/spec/controllers/polls_controller_spec.rb
+++ b/plugins/poll/spec/controllers/polls_controller_spec.rb
@@ -10,7 +10,7 @@ describe ::DiscoursePoll::PollsController do
   describe "#vote" do
 
     it "works" do
-      DiscourseBus.expects(:publish)
+      MessageBus.expects(:publish)
 
       xhr :put, :vote, { post_id: poll.id, poll_name: "poll", options: ["5c24fc1df56d764b550ceae1b9319125"] }
 
@@ -84,7 +84,7 @@ describe ::DiscoursePoll::PollsController do
   describe "#toggle_status" do
 
     it "works for OP" do
-      DiscourseBus.expects(:publish)
+      MessageBus.expects(:publish)
 
       xhr :put, :toggle_status, { post_id: poll.id, poll_name: "poll", status: "closed" }
       expect(response).to be_success
@@ -94,7 +94,7 @@ describe ::DiscoursePoll::PollsController do
 
     it "works for staff" do
       log_in(:moderator)
-      DiscourseBus.expects(:publish)
+      MessageBus.expects(:publish)
 
       xhr :put, :toggle_status, { post_id: poll.id, poll_name: "poll", status: "closed" }
       expect(response).to be_success
diff --git a/spec/components/discourse_spec.rb b/spec/components/discourse_spec.rb
index 45685d92e..5765a6d42 100644
--- a/spec/components/discourse_spec.rb
+++ b/spec/components/discourse_spec.rb
@@ -89,7 +89,7 @@ describe Discourse do
 
     it "adds a key in redis and publish a message through the message bus" do
       $redis.expects(:set).with(Discourse.readonly_mode_key, 1)
-      DiscourseBus.expects(:publish).with(Discourse.readonly_channel, true)
+      MessageBus.expects(:publish).with(Discourse.readonly_channel, true)
       Discourse.enable_readonly_mode
     end
 
@@ -99,7 +99,7 @@ describe Discourse do
 
     it "removes a key from redis and publish a message through the message bus" do
       $redis.expects(:del).with(Discourse.readonly_mode_key)
-      DiscourseBus.expects(:publish).with(Discourse.readonly_channel, false)
+      MessageBus.expects(:publish).with(Discourse.readonly_channel, false)
       Discourse.disable_readonly_mode
     end
 
diff --git a/spec/components/post_creator_spec.rb b/spec/components/post_creator_spec.rb
index c356a4331..411e8d715 100644
--- a/spec/components/post_creator_spec.rb
+++ b/spec/components/post_creator_spec.rb
@@ -72,7 +72,7 @@ describe PostCreator do
 
       it "does not notify on system messages" do
         admin = Fabricate(:admin)
-        messages = DiscourseBus.track_publish do
+        messages = MessageBus.track_publish do
           p = PostCreator.create(admin, basic_topic_params.merge(post_type: Post.types[:moderator_action]))
           PostCreator.create(admin, basic_topic_params.merge(topic_id: p.topic_id, post_type: Post.types[:moderator_action]))
         end
@@ -93,7 +93,7 @@ describe PostCreator do
         created_post = nil
         reply = nil
 
-        messages = DiscourseBus.track_publish do
+        messages = MessageBus.track_publish do
           created_post = PostCreator.new(admin, basic_topic_params.merge(category: cat.id)).create
           reply = PostCreator.new(admin, raw: "this is my test reply 123 testing", topic_id: created_post.topic_id).create
         end
@@ -118,7 +118,7 @@ describe PostCreator do
       it 'generates the correct messages for a normal topic' do
 
         p = nil
-        messages = DiscourseBus.track_publish do
+        messages = MessageBus.track_publish do
           p = creator.create
         end
 
diff --git a/spec/models/topic_spec.rb b/spec/models/topic_spec.rb
index a7ca9549d..66ce8e17b 100644
--- a/spec/models/topic_spec.rb
+++ b/spec/models/topic_spec.rb
@@ -573,7 +573,7 @@ describe Topic do
     describe "make_banner!" do
 
       it "changes the topic archetype to 'banner'" do
-        messages = DiscourseBus.track_publish do
+        messages = MessageBus.track_publish do
           topic.make_banner!(user)
           expect(topic.archetype).to eq(Archetype.banner)
         end
@@ -597,7 +597,7 @@ describe Topic do
 
       it "resets the topic archetype" do
         topic.expects(:add_moderator_post)
-        DiscourseBus.expects(:publish).with("/site/banner", nil)
+        MessageBus.expects(:publish).with("/site/banner", nil)
         topic.remove_banner!(user)
         expect(topic.archetype).to eq(Archetype.default)
       end