diff --git a/.rubocop.yml b/.rubocop.yml
index ac924d8bf..b74689518 100644
--- a/.rubocop.yml
+++ b/.rubocop.yml
@@ -166,6 +166,9 @@ Layout/TrailingWhitespace:
 Lint/AmbiguousRegexpLiteral:
   Enabled: true
 
+Lint/ConstantDefinitionInBlock:
+  Enabled: true
+
 Lint/DuplicateMethods:
   Enabled: true
 
diff --git a/spec/lib/consul_form_builder_spec.rb b/spec/lib/consul_form_builder_spec.rb
index 91d22ab89..ed73b6b62 100644
--- a/spec/lib/consul_form_builder_spec.rb
+++ b/spec/lib/consul_form_builder_spec.rb
@@ -1,10 +1,14 @@
 require "rails_helper"
 
 describe ConsulFormBuilder do
-  class DummyModel
-    include ActiveModel::Model
-    OPTIONS = %w[Good Bad Ugly].freeze
-    attr_accessor :title, :quality
+  before do
+    dummy_model = Class.new do
+      include ActiveModel::Model
+      attr_accessor :title, :quality
+    end
+
+    stub_const("DummyModel", dummy_model)
+    stub_const("DummyModel::OPTIONS", %w[Good Bad Ugly].freeze)
   end
 
   let(:builder) { ConsulFormBuilder.new(:dummy, DummyModel.new, ActionView::Base.new, {}) }
diff --git a/spec/models/statisticable_spec.rb b/spec/models/statisticable_spec.rb
index 3757d3db8..1cc57ca2a 100644
--- a/spec/models/statisticable_spec.rb
+++ b/spec/models/statisticable_spec.rb
@@ -1,12 +1,16 @@
 require "rails_helper"
 
 describe Statisticable do
-  class DummyStats
-    include Statisticable
+  before do
+    dummy_stats = Class.new do
+      include Statisticable
 
-    def participants
-      User.all
+      def participants
+        User.all
+      end
     end
+
+    stub_const("DummyStats", dummy_stats)
   end
 
   let(:stats) { DummyStats.new(nil) }
diff --git a/spec/shared/system/nested_documentable.rb b/spec/shared/system/nested_documentable.rb
index 9c6482d84..a44096f06 100644
--- a/spec/shared/system/nested_documentable.rb
+++ b/spec/shared/system/nested_documentable.rb
@@ -235,12 +235,11 @@ shared_examples "nested documentable" do |login_as_name, documentable_factory_na
       end
       login_as user_to_login
       visit send(path, arguments)
-      FILENAMES ||= %w[clippy empty logo].freeze
 
       send(fill_resource_method_name) if fill_resource_method_name
 
-      documentable.class.max_documents_allowed.times.zip(FILENAMES).each do |_n, fn|
-        documentable_attach_new_file(Rails.root.join("spec/fixtures/files/#{fn}.pdf"))
+      %w[clippy empty logo].take(documentable.class.max_documents_allowed).each do |filename|
+        documentable_attach_new_file(Rails.root.join("spec/fixtures/files/#{filename}.pdf"))
       end
 
       click_on submit_button
diff --git a/spec/views/shared/errors_spec.rb b/spec/views/shared/errors_spec.rb
index 6e3c4ec49..1159f58c7 100644
--- a/spec/views/shared/errors_spec.rb
+++ b/spec/views/shared/errors_spec.rb
@@ -1,13 +1,17 @@
 require "rails_helper"
 
 describe "shared errors" do
-  class DummyModel
-    include ActiveModel::Model
-    attr_accessor :title, :description, :days
+  before do
+    dummy_model = Class.new do
+      include ActiveModel::Model
+      attr_accessor :title, :description, :days
 
-    validates :title, presence: true
-    validates :description, presence: true, length: { in: 10..100 }
-    validates :days, numericality: { greater_than: 10 }
+      validates :title, presence: true
+      validates :description, presence: true, length: { in: 10..100 }
+      validates :days, numericality: { greater_than: 10 }
+    end
+
+    stub_const("DummyModel", dummy_model)
   end
 
   it "counts the number of fields with errors" do