diff --git a/app/controllers/main_controller.rb b/app/controllers/main_controller.rb
index 9bef4964..03f928ce 100644
--- a/app/controllers/main_controller.rb
+++ b/app/controllers/main_controller.rb
@@ -160,9 +160,9 @@ class MainController < ApplicationController
         desc = s.desc.nil? || s.desc == '' ? '' : s.desc.strip
         if collectedDesc.index(desc).nil?
           collectedDesc.push(desc)
-          boolean = false
+          false # return this value
         else
-          boolean = true
+          true # return this value
         end
       end
     elsif topic1id && !topic1id.empty?
diff --git a/app/controllers/maps_controller.rb b/app/controllers/maps_controller.rb
index 6d9bc7c5..90d2c320 100644
--- a/app/controllers/maps_controller.rb
+++ b/app/controllers/maps_controller.rb
@@ -250,7 +250,7 @@ class MapsController < ApplicationController
     end
     removed = @map.collaborators.select { |user| !userIds.include?(user.id.to_s) }.map(&:id)
     added.each do |uid|
-      um = UserMap.create(user_id: uid.to_i, map_id: @map.id)
+      UserMap.create(user_id: uid.to_i, map_id: @map.id)
       user = User.find(uid.to_i)
       MapMailer.invite_to_edit_email(@map, current_user, user).deliver_later
     end
diff --git a/app/helpers/devise_helper.rb b/app/helpers/devise_helper.rb
index e0ae764e..5081cba0 100644
--- a/app/helpers/devise_helper.rb
+++ b/app/helpers/devise_helper.rb
@@ -1,21 +1,6 @@
 module DeviseHelper
   def devise_error_messages!
-    message = resource.errors.to_a[0]
-    # return "" if resource.errors.empty?
-
-    # messages = resource.errors.full_messages.map { |msg| content_tag(:li, msg) }.join
-    # sentence = I18n.t("errors.messages.not_saved",
-    #                  :count => resource.errors.count,
-    #                  :resource => resource.class.model_name.human.downcase)
-
-    # html = <<-HTML
-    # <div id="error_explanation">
-    #  <h2>#{sentence}</h2>
-    #  <ul>#{messages}</ul>
-    # </div>
-    # HTML
-
-    # html.html_safe
+    resource.errors.to_a[0]
   end
 
   def devise_error_messages?
diff --git a/app/models/events/conversation_started_on_map.rb b/app/models/events/conversation_started_on_map.rb
index 20812874..4ca922be 100644
--- a/app/models/events/conversation_started_on_map.rb
+++ b/app/models/events/conversation_started_on_map.rb
@@ -7,12 +7,4 @@ class Events::ConversationStartedOnMap < Event
             map: map,
             user: user)
   end
-
-  private
-
-  # def notify_users!
-  #  unless comment_vote.user == comment_vote.comment_user
-  #    notify!(comment_vote.comment_user)
-  #  end
-  # end
 end
diff --git a/app/models/events/new_mapping.rb b/app/models/events/new_mapping.rb
index 2a7d9ef1..d7b91576 100644
--- a/app/models/events/new_mapping.rb
+++ b/app/models/events/new_mapping.rb
@@ -7,12 +7,4 @@ class Events::NewMapping < Event
             map: mapping.map,
             user: user)
   end
-
-  private
-
-  # def notify_users!
-  #  unless comment_vote.user == comment_vote.comment_user
-  #    notify!(comment_vote.comment_user)
-  #  end
-  # end
 end
diff --git a/app/models/events/user_present_on_map.rb b/app/models/events/user_present_on_map.rb
index 90469224..45726002 100644
--- a/app/models/events/user_present_on_map.rb
+++ b/app/models/events/user_present_on_map.rb
@@ -7,12 +7,4 @@ class Events::UserPresentOnMap < Event
             map: map,
             user: user)
   end
-
-  private
-
-  # def notify_users!
-  #  unless comment_vote.user == comment_vote.comment_user
-  #    notify!(comment_vote.comment_user)
-  #  end
-  # end
 end
diff --git a/app/services/webhook_service.rb b/app/services/webhook_service.rb
index ae19b798..965f2c91 100644
--- a/app/services/webhook_service.rb
+++ b/app/services/webhook_service.rb
@@ -4,13 +4,13 @@ class WebhookService
     HTTParty.post webhook.uri, body: payload_for(webhook, event), headers: webhook.headers
   end
 
-  private
+  class << self
+    def payload_for(webhook, event)
+      WebhookSerializer.new(webhook_object_for(webhook, event), root: false).to_json
+    end
 
-  def self.payload_for(webhook, event)
-    WebhookSerializer.new(webhook_object_for(webhook, event), root: false).to_json
-  end
-
-  def self.webhook_object_for(webhook, event)
-    "Webhooks::#{webhook.kind.classify}::#{event.kind.classify}".constantize.new(event)
+    def webhook_object_for(webhook, event)
+      "Webhooks::#{webhook.kind.classify}::#{event.kind.classify}".constantize.new(event)
+    end
   end
 end
diff --git a/lib/tasks/heroku.rake b/lib/tasks/heroku.rake
index adf58330..a523a778 100644
--- a/lib/tasks/heroku.rake
+++ b/lib/tasks/heroku.rake
@@ -6,7 +6,7 @@ namespace :heroku do
     RAILS_ENV = 'production'.freeze
     Rake::Task[:environment].invoke
     list = Rails.configuration.gems.collect do |g|
-      command, *options = g.send(:install_command)
+      _command, *options = g.send(:install_command)
       options.join(' ') + "\n"
     end
 
diff --git a/spec/models/token_spec.rb b/spec/models/token_spec.rb
index 17ec021f..50e89c02 100644
--- a/spec/models/token_spec.rb
+++ b/spec/models/token_spec.rb
@@ -2,9 +2,9 @@ require 'rails_helper'
 
 RSpec.describe Token, type: :model do
   context '#generate_token' do
-    subject (:token) { Token.new }
+    subject(:token) { Token.new }
     it 'should generate an alphanumeric token of 32 characters' do
-      expect(token.send(:generate_token)).to match /^[a-zA-Z0-9]{32}$/
+      expect(token.send(:generate_token)).to match(/^[a-zA-Z0-9]{32}$/)
     end
   end
 end