diff --git a/db/fixtures/development/13_comments.rb b/db/fixtures/development/13_comments.rb
index 29b8081055d30a429f09680d4e154277157b2760..bc2d74c8034aac8710d422ee44c4ec193f7b6134 100644
--- a/db/fixtures/development/13_comments.rb
+++ b/db/fixtures/development/13_comments.rb
@@ -1,7 +1,7 @@
 require './spec/support/sidekiq'
 
 Gitlab::Seeder.quiet do
-  Issue.all.each do |issue|
+  Issue.find_each do |issue|
     project = issue.project
 
     project.team.users.each do |user|
@@ -16,7 +16,7 @@ Gitlab::Seeder.quiet do
     end
   end
 
-  MergeRequest.all.each do |mr|
+  MergeRequest.find_each do |mr|
     project = mr.project
 
     project.team.users.each do |user|
diff --git a/lib/gitlab/seeder.rb b/lib/gitlab/seeder.rb
index b7f825e8284596c31db20d8c50c97f7e8429ef8c..823f697f51cfa9a0a86067ae3b3b5edef31c9206 100644
--- a/lib/gitlab/seeder.rb
+++ b/lib/gitlab/seeder.rb
@@ -1,24 +1,23 @@
+module DeliverNever
+  def deliver_later
+    self
+  end
+end
+
 module Gitlab
   class Seeder
     def self.quiet
       mute_mailer
       SeedFu.quiet = true
+
       yield
+
       SeedFu.quiet = false
       puts "\nOK".color(:green)
     end
 
-    def self.by_user(user)
-      yield
-    end
-
     def self.mute_mailer
-      code = <<-eos
-def Notify.deliver_later
-  self
-end
-      eos
-      eval(code) # rubocop:disable Security/Eval
+      ActionMailer::MessageDelivery.prepend(DeliverNever)
     end
   end
 end