diff --git a/app/helpers/transaction_helper.rb b/app/helpers/transaction_helper.rb
deleted file mode 100644
index efb98d6a53e..00000000000
--- a/app/helpers/transaction_helper.rb
+++ /dev/null
@@ -1,38 +0,0 @@
-##
-# Allows running arbitrary code after the current transaction has been committed.
-# Works even with nested transactions. Useful for scheduling sidekiq jobs.
-# Slightly simplified version of https://dev.to/evilmartians/rails-aftercommit-everywhere--4j9g
-# Usage:
-#    Topic.transaction do
-#        puts "Some work before scheduling"
-#        TransactionHelper.after_commit do
-#            puts "Running after commit"
-#        end
-#        puts "Some work after scheduling"
-#    end
-#
-# Produces:
-#     > Some work before scheduling
-#     > Some work after scheduling
-#     > Running after commit
-
-module TransactionHelper
-  class AfterCommitWrapper
-    def initialize
-      @callback = Proc.new
-    end
-
-    def committed!(*)
-      @callback.call
-    end
-
-    def before_committed!(*); end
-    def rolledback!(*); end
-  end
-
-  def self.after_commit(&blk)
-    ActiveRecord::Base.connection.add_transaction_record(
-      AfterCommitWrapper.new(&blk)
-    )
-  end
-end
diff --git a/app/models/topic.rb b/app/models/topic.rb
index 2aa41f6bb6b..94f2a8566fc 100644
--- a/app/models/topic.rb
+++ b/app/models/topic.rb
@@ -686,7 +686,7 @@ class Topic < ActiveRecord::Base
 
         if post = self.ordered_posts.first
           notified_user_ids = [post.user_id, post.last_editor_id].uniq
-          TransactionHelper.after_commit do
+          DB.after_commit do
             Jobs.enqueue(:notify_category_change, post_id: post.id, notified_user_ids: notified_user_ids)
           end
         end
diff --git a/lib/mini_sql_multisite_connection.rb b/lib/mini_sql_multisite_connection.rb
index c6842fe19ab..c628ef644b5 100644
--- a/lib/mini_sql_multisite_connection.rb
+++ b/lib/mini_sql_multisite_connection.rb
@@ -23,6 +23,27 @@ class MiniSqlMultisiteConnection < MiniSql::Connection
     end
   end
 
+  class AfterCommitWrapper
+    def initialize
+      @callback = Proc.new
+    end
+
+    def committed!(*)
+      @callback.call
+    end
+
+    def before_committed!(*); end
+    def rolledback!(*); end
+  end
+
+  # Allows running arbitrary code after the current transaction has been committed.
+  # Works even with nested transactions. Useful for scheduling sidekiq jobs.
+  def after_commit(&blk)
+    ActiveRecord::Base.connection.add_transaction_record(
+      AfterCommitWrapper.new(&blk)
+    )
+  end
+
   def self.instance
     new(nil, param_encoder: ParamEncoder.new)
   end
diff --git a/spec/helpers/transaction_helper_spec.rb b/spec/helpers/transaction_helper_spec.rb
deleted file mode 100644
index 01908b15aaa..00000000000
--- a/spec/helpers/transaction_helper_spec.rb
+++ /dev/null
@@ -1,32 +0,0 @@
-require 'rails_helper'
-
-describe TransactionHelper do
-
-  it "runs callbacks after outermost transaction is committed" do
-    outputString = "1"
-
-    # Main transaction
-    ActiveRecord::Base.transaction do  
-      outputString += "2"
-
-        # Nested transaction
-        ActiveRecord::Base.transaction do
-          outputString += "3"
-
-            TransactionHelper.after_commit do
-              outputString += "6"
-            end
-            outputString += "4"
-        end
-
-        TransactionHelper.after_commit do
-          outputString += "7"
-        end
-
-        outputString += "5"
-    end
-
-    expect(outputString).to eq("1234567")
-  end
-
-end
diff --git a/spec/lib/mini_sql_multisite_connection_spec.rb b/spec/lib/mini_sql_multisite_connection_spec.rb
new file mode 100644
index 00000000000..c4213d9180d
--- /dev/null
+++ b/spec/lib/mini_sql_multisite_connection_spec.rb
@@ -0,0 +1,52 @@
+require 'rails_helper'
+
+describe MiniSqlMultisiteConnection do
+
+  describe "after_commit" do
+    it "runs callbacks after outermost transaction is committed" do
+      outputString = "1"
+
+      # Main transaction
+      ActiveRecord::Base.transaction do  
+        outputString += "2"
+
+          # Nested transaction
+          ActiveRecord::Base.transaction do
+            outputString += "3"
+
+              DB.after_commit do
+                outputString += "6"
+              end
+              outputString += "4"
+          end
+
+          DB.after_commit do
+            outputString += "7"
+          end
+
+          outputString += "5"
+      end
+
+      expect(outputString).to eq("1234567")
+    end
+
+    it "does not run if the transaction is rolled back" do
+      outputString = "1"
+
+      ActiveRecord::Base.transaction do
+        outputString += "2"
+
+        DB.after_commit do
+          outputString += "4"
+        end
+
+        outputString += "3"
+
+        raise ActiveRecord::Rollback
+      end
+
+      expect(outputString).to eq("123")
+    end
+  end
+
+end