diff --git a/app/admin/category.rb b/app/admin/category.rb
index bb07c7e69..009b14c12 100644
--- a/app/admin/category.rb
+++ b/app/admin/category.rb
@@ -13,8 +13,7 @@
   form do |f|
     f.inputs do
       f.input :name
-      f.input :icon_name,
-              hint: "See all available <a href='https://getbootstrap.com/docs/3.3/components/#glyphicons' target='_blank'>icons here</a>".html_safe
+      f.input :icon_name, hint: "See all available <a href='https://getbootstrap.com/docs/3.3/components/#glyphicons' target='_blank'>icons here</a>".html_safe
     end
     f.actions
   end
diff --git a/app/admin/organization.rb b/app/admin/organization.rb
index b04e18587..62f85c35d 100644
--- a/app/admin/organization.rb
+++ b/app/admin/organization.rb
@@ -73,5 +73,5 @@ def destroy
   filter :updated_at
 
   permit_params :name, :email, :web, :phone, :city, :neighborhood,
-                :address, :description, :public_opening_times, :logo
+    :address, :description, :public_opening_times, :logo
 end
diff --git a/app/admin/post.rb b/app/admin/post.rb
index cdfdf9527..c0d0e5057 100644
--- a/app/admin/post.rb
+++ b/app/admin/post.rb
@@ -46,7 +46,7 @@
   end
 
   permit_params :type, :tag_list, :title, :category_id, :user_id,
-                :description, :organization_id, :active, :is_group
+    :description, :organization_id, :active, :is_group
 
   filter :type, as: :select, collection: -> { Post.subclasses }
   filter :id
diff --git a/app/admin/transfer.rb b/app/admin/transfer.rb
index 88b752a93..7857e1422 100644
--- a/app/admin/transfer.rb
+++ b/app/admin/transfer.rb
@@ -1,5 +1,5 @@
 ActiveAdmin.register Transfer do
-  includes :post, movements: { account: %i[accountable organization] }
+  includes :post, movements: { account: [:accountable, :organization] }
 
   actions :index, :destroy
 
diff --git a/app/admin/user.rb b/app/admin/user.rb
index 83faec2f3..060f9e844 100644
--- a/app/admin/user.rb
+++ b/app/admin/user.rb
@@ -85,5 +85,5 @@
   end
 
   permit_params :username, :email, :phone, :postcode, :gender, :locale,
-                members_attributes: %i[id organization_id active manager _destroy]
+    members_attributes: [:id, :organization_id, :active, :manager, :_destroy]
 end
diff --git a/app/assets/javascripts/libs.js b/app/assets/javascripts/libs.js
index c304764cd..1c941bd13 100644
--- a/app/assets/javascripts/libs.js
+++ b/app/assets/javascripts/libs.js
@@ -1,7 +1,7 @@
 //= require jquery2
 //= require jquery_ujs
-//= require vendor/jquery.validate
+//= require jquery.validate
 //= require bootstrap
-//= require ./vendor/highcharts
-//= require ./vendor/highcharts-exporting
+//= require highcharts
+//= require highcharts-exporting
 //= require select2
diff --git a/app/controllers/application_controller.rb b/app/controllers/application_controller.rb
index e90142817..a8823c0c8 100644
--- a/app/controllers/application_controller.rb
+++ b/app/controllers/application_controller.rb
@@ -114,18 +114,18 @@ def set_locale
 
   def user_not_authorized
     flash[:error] = "You are not authorized to perform this action."
-    redirect_to(request.referer || root_path)
+    redirect_to(request.referrer || root_path)
   end
 
   def resource_not_found
-    render "errors/not_found", status: :not_found
+    render 'errors/not_found', status: 404
   end
 
   def member_should_exist_and_be_active
     if !current_member
       redirect_to organizations_path
     elsif !current_member.active
-      flash[:error] = I18n.t("users.index.account_deactivated")
+      flash[:error] = I18n.t('users.index.account_deactivated')
       redirect_to select_organization_path
     end
   end
diff --git a/app/controllers/concerns/with_transfer_params.rb b/app/controllers/concerns/with_transfer_params.rb
index 934cf6e8c..a9b766369 100644
--- a/app/controllers/concerns/with_transfer_params.rb
+++ b/app/controllers/concerns/with_transfer_params.rb
@@ -1,10 +1,10 @@
 module WithTransferParams
   def transfer_params
-    permitted_transfer_params = %i[
-      destination
-      amount
-      reason
-      post_id
+    permitted_transfer_params = [
+      :destination,
+      :amount,
+      :reason,
+      :post_id,
     ]
 
     permitted_transfer_params.push(:source) if admin?
diff --git a/app/controllers/errors_controller.rb b/app/controllers/errors_controller.rb
index c000e9c97..479fe79df 100644
--- a/app/controllers/errors_controller.rb
+++ b/app/controllers/errors_controller.rb
@@ -1,9 +1,9 @@
 class ErrorsController < ApplicationController
   def not_found
-    render status: :not_found
+    render status: 404
   end
 
   def internal_server_error
-    render status: :internal_server_error
+    render status: 500
   end
 end
diff --git a/app/controllers/multi_transfers_controller.rb b/app/controllers/multi_transfers_controller.rb
index e78a6bc54..91f45a0b9 100644
--- a/app/controllers/multi_transfers_controller.rb
+++ b/app/controllers/multi_transfers_controller.rb
@@ -1,12 +1,12 @@
 class MultiTransfersController < ApplicationController
   include WithTransferParams
 
-  STEPS = %w[
-    select_type
-    select_source
-    select_target
-    set_params
-    confirm
+  STEPS = [
+    'select_type',
+    'select_source',
+    'select_target',
+    'set_params',
+    'confirm'
   ]
 
   def step
@@ -60,10 +60,11 @@ def prepare_template_vars
       @target_accountable = Account.find(@to.first).accountable
     end
 
-    @should_render_offer_selector =
+    @should_render_offer_selector = (
       @type_of_transfer.to_sym == :many_to_one &&
       @target_accountable &&
       @target_accountable.offers.length > 0
+    )
 
     @from_names = Account.find(@from).map(&:accountable).map(&:to_s)
     @to_names = Account.find(@to).map(&:accountable).map(&:to_s)
diff --git a/app/controllers/organizations_controller.rb b/app/controllers/organizations_controller.rb
index 45d1b747c..37daeafcc 100644
--- a/app/controllers/organizations_controller.rb
+++ b/app/controllers/organizations_controller.rb
@@ -1,5 +1,5 @@
 class OrganizationsController < ApplicationController
-  before_action :load_resource, only: %i[show edit update set_current]
+  before_action :load_resource, only: [:show, :edit, :update, :set_current]
   before_action :user_should_be_confirmed
 
   def index
diff --git a/app/controllers/pages_controller.rb b/app/controllers/pages_controller.rb
index f4264dbae..771445e51 100644
--- a/app/controllers/pages_controller.rb
+++ b/app/controllers/pages_controller.rb
@@ -1,7 +1,9 @@
 class PagesController < ApplicationController
   def show
-    render template: "pages/#{params[:page]}"
-  rescue ActionView::MissingTemplate
-    render "errors/not_found", status: :not_found
+    begin
+      render template: "pages/#{params[:page]}"
+    rescue ActionView::MissingTemplate
+      render "errors/not_found", status: 404
+    end
   end
 end
diff --git a/app/controllers/petitions_controller.rb b/app/controllers/petitions_controller.rb
index a897f4e9a..8dc4d432b 100644
--- a/app/controllers/petitions_controller.rb
+++ b/app/controllers/petitions_controller.rb
@@ -9,9 +9,9 @@ def create
       OrganizationNotifier.new_petition(petition).deliver_now
       OrganizationNotifier.petition_sent(petition).deliver_now
 
-      flash[:notice] = t("petitions.application_status", status: t("petitions.status.sent"))
+      flash[:notice] = t('petitions.application_status', status: t("petitions.status.sent"))
     else
-      flash[:error] = t("errors.internal_server_error.description")
+      flash[:error] = t('errors.internal_server_error.description')
     end
 
     redirect_back fallback_location: organization_path(petition.organization)
@@ -22,19 +22,18 @@ def update
     status = params[:status]
 
     if petition.update(status: status)
-      petition.user.add_to_organization(petition.organization) if status == "accepted"
-      flash[:notice] = t("petitions.application_status", status: t("petitions.status.#{status}"))
+      petition.user.add_to_organization(petition.organization) if status == 'accepted'
+      flash[:notice] = t('petitions.application_status', status: t("petitions.status.#{status}"))
     else
-      flash[:error] = t("errors.internal_server_error.description")
+      flash[:error] = t('errors.internal_server_error.description')
     end
 
     redirect_to manage_petitions_path
   end
 
   def manage
-    @status = params[:status] || "pending"
-    @users = User.joins(:petitions).where(petitions: { organization_id: current_organization.id,
-                                                       status: @status }).page(params[:page]).per(20)
+    @status = params[:status] || 'pending'
+    @users = User.joins(:petitions).where(petitions: { organization_id: current_organization.id, status: @status }).page(params[:page]).per(20)
   end
 
   private
diff --git a/app/controllers/posts_controller.rb b/app/controllers/posts_controller.rb
index 2e45c608a..5a8e3616b 100644
--- a/app/controllers/posts_controller.rb
+++ b/app/controllers/posts_controller.rb
@@ -1,4 +1,4 @@
-class PostsController < ApplicationController
+class PostsController <  ApplicationController
   has_scope :by_category, as: :cat
   has_scope :tagged_with, as: :tag
   has_scope :by_organization, as: :org
@@ -91,7 +91,7 @@ def set_user_id(p)
 
   def post_params
     permitted_fields = [:description, :end_on, :start_on, :title, :category_id,
-                        :user_id, :is_group, :active, { tag_list: [] }]
+                        :user_id, :is_group, :active, tag_list: []]
 
     params.fetch(resource, {}).permit(*permitted_fields).tap do |p|
       set_user_id(p)
diff --git a/app/controllers/reports_controller.rb b/app/controllers/reports_controller.rb
index d7749ea35..5b2b271fa 100644
--- a/app/controllers/reports_controller.rb
+++ b/app/controllers/reports_controller.rb
@@ -1,4 +1,4 @@
-require "zip"
+require 'zip'
 
 class ReportsController < ApplicationController
   before_action :authenticate_user!
@@ -8,20 +8,20 @@ class ReportsController < ApplicationController
   def user_list
     @members = report_collection("Member")
 
-    report_responder("Member", current_organization, @members)
+    report_responder('Member', current_organization, @members)
   end
 
   def post_list
     @post_type = (params[:type] || "offer").capitalize.constantize
     @posts = report_collection(@post_type)
 
-    report_responder("Post", current_organization, @posts, @post_type)
+    report_responder('Post', current_organization, @posts, @post_type)
   end
 
   def transfer_list
-    @transfers = report_collection("Transfer")
+    @transfers = report_collection('Transfer')
 
-    report_responder("Transfer", current_organization, @transfers)
+    report_responder('Transfer', current_organization, @transfers)
   end
 
   def download_all
@@ -35,7 +35,7 @@ def download_all
         end
       end
       zip_data = File.read(temp_file.path)
-      send_data(zip_data, type: "application/zip", disposition: "attachment", filename: filename)
+      send_data(zip_data, type: 'application/zip', disposition: 'attachment', filename: filename)
     rescue Errno::ENOENT
       redirect_to download_all_report_path
     ensure
@@ -65,11 +65,11 @@ def get_report(report_class, *args)
 
   def report_collection(report_class)
     case report_class.to_s
-    when "Member"
-      current_organization.members.active.includes(:user).order("members.member_uid")
-    when "Transfer"
+    when 'Member'
+      current_organization.members.active.includes(:user).order('members.member_uid')
+    when 'Transfer'
       current_organization.all_transfers_with_accounts
-    when "Inquiry", "Offer"
+    when 'Inquiry', 'Offer'
       report_class = report_class.constantize if report_class.is_a?(String)
 
       current_organization.posts.of_active_members.active.
@@ -84,10 +84,10 @@ def add_csv_to_zip(report_class, zip)
     collection = report_collection(report_class)
 
     report = if report_class.in? %w(Inquiry Offer)
-               get_report("Csv::Post", current_organization, collection, report_class.constantize)
-             else
-               get_report("Csv::#{report_class}", current_organization, collection)
-             end
+      get_report("Csv::Post", current_organization, collection, report_class.constantize)
+    else
+      get_report("Csv::#{report_class}", current_organization, collection)
+    end
 
     file = Tempfile.new
     file.write(report.run)
diff --git a/app/controllers/statistics_controller.rb b/app/controllers/statistics_controller.rb
index 8d705c327..aa719b219 100644
--- a/app/controllers/statistics_controller.rb
+++ b/app/controllers/statistics_controller.rb
@@ -8,16 +8,16 @@ def global_activity
     @total_hours = num_movements = 0
     members.each do |m|
       num_movements += m.account.movements.count
-      @total_hours += m.account.movements.map do |a|
-        a.amount > 0 ? a.amount : 0
+      @total_hours += m.account.movements.map do
+        |a| (a.amount > 0) ? a.amount : 0
       end.inject(0, :+)
     end
     @total_hours += current_organization.account.movements.
-                    map { |a| a.amount > 0 ? a.amount : 0 }.inject(0, :+)
+                    map { |a| (a.amount > 0) ? a.amount : 0 }.inject(0, :+)
 
     @num_swaps = (num_movements + current_organization.account.movements.count) / 2
 
-    from = params[:from].presence.try(:to_date) || DateTime.now.to_date - 5.months
+    from = params[:from].presence.try(:to_date) || DateTime.now.to_date - 5.month
     to = params[:to].presence.try(:to_date) || DateTime.now.to_date
     num_months = (to.year * 12 + to.month) - (from.year * 12 + from.month) + 1
     date = from
@@ -38,10 +38,10 @@ def global_activity
 
       sum_hours = 0
       swaps_members.flatten.each do |s|
-        sum_hours += s.amount > 0 ? s.amount : 0
+        sum_hours += (s.amount > 0) ? s.amount : 0
       end
-      sum_hours += swaps_organization.map do |a|
-        a.amount > 0 ? a.amount : 0
+      sum_hours += swaps_organization.map do
+        |a| (a.amount > 0) ? a.amount : 0
       end.inject(0, :+)
       sum_hours = sum_hours / 3600.0 if sum_hours > 0
       @hours_swaps_months << sum_hours
@@ -147,12 +147,12 @@ def compute_age(date_of_birth)
 
   def age_group_labels
     {
-      0..17 => "-17",
-      18..24 => "18-24",
-      25..34 => "25-34",
-      35..44 => "35-44",
-      45..54 => "45-54",
-      55..64 => "55-64",
+      0..17   => "-17",
+      18..24  => "18-24",
+      25..34  => "25-34",
+      35..44  => "35-44",
+      45..54  => "45-54",
+      55..64  => "55-64",
       65..100 => "65+",
     }
   end
@@ -161,10 +161,10 @@ def gender_counts(members)
     members.each_with_object(Hash.new(0)) do |member, counts|
       gender = member.user_gender
       gender_label = if gender.present?
-                       t("simple_form.options.user.gender.#{gender}")
-                     else
-                       t("statistics.demographics.unknown")
-                     end
+        t("simple_form.options.user.gender.#{gender}")
+      else
+        t("statistics.demographics.unknown")
+      end
       counts[gender_label] += 1
     end
   end
diff --git a/app/controllers/transfers_controller.rb b/app/controllers/transfers_controller.rb
index 5baf275ba..e65506566 100644
--- a/app/controllers/transfers_controller.rb
+++ b/app/controllers/transfers_controller.rb
@@ -14,8 +14,7 @@ def create
     if persister.save
       redirect_to redirect_target
     else
-      redirect_back fallback_location: redirect_target,
-                    alert: transfer.errors.full_messages.to_sentence
+      redirect_back fallback_location: redirect_target, alert: transfer.errors.full_messages.to_sentence
     end
   end
 
diff --git a/app/controllers/users_controller.rb b/app/controllers/users_controller.rb
index c464d76bd..689adef37 100644
--- a/app/controllers/users_controller.rb
+++ b/app/controllers/users_controller.rb
@@ -1,8 +1,7 @@
 class UsersController < ApplicationController
   before_action :authenticate_user!, except: %i[signup create]
   before_action :user_should_be_confirmed, except: %i[signup create please_confirm]
-  before_action :member_should_exist_and_be_active,
-                except: %i[signup create edit show update please_confirm]
+  before_action :member_should_exist_and_be_active, except: %i[signup create edit show update please_confirm]
 
   has_scope :tagged_with, as: :tag
 
@@ -10,11 +9,11 @@ def index
     members = current_organization.members.active
     members = apply_scopes(members)
 
-    search_and_load_members members, { s: "user_last_sign_in_at DESC" }
+    search_and_load_members members, { s: 'user_last_sign_in_at DESC' }
   end
 
   def manage
-    search_and_load_members current_organization.members, { s: "member_uid ASC" }
+    search_and_load_members current_organization.members, { s: 'member_uid ASC' }
   end
 
   def show
@@ -56,7 +55,7 @@ def create
     else
       @user.email = "" if empty_email
 
-      render action: @user.from_signup ? "signup" : "new"
+      render action: @user.from_signup ? 'signup' : 'new'
     end
   end
 
@@ -99,9 +98,7 @@ def search_and_load_members(members_scope, default_search_params)
     @search = members_scope.ransack(default_search_params.merge(params.to_unsafe_h.fetch(:q, {})))
 
     result = @search.result
-    orders = result.order_values.map do |order|
-      order.direction == :asc ? "#{order.to_sql} NULLS FIRST" : "#{order.to_sql} NULLS LAST"
-    end
+    orders = result.order_values.map { |order| order.direction == :asc ? "#{order.to_sql} NULLS FIRST" : "#{order.to_sql} NULLS LAST" }
     result = result.except(:order).order(orders.join(", ")) if orders.count > 0
 
     @members = result.eager_load(:account, :user).page(params[:page]).per(20)
@@ -117,10 +114,8 @@ def scoped_users
   def user_params
     fields_to_permit = %w"gender username email date_of_birth phone alt_phone active
                           locale description notifications push_notifications postcode"
-    if admin?
-      fields_to_permit += %w"admin registration_number
-                             registration_date"
-    end
+    fields_to_permit += %w"admin registration_number
+                           registration_date" if admin?
     fields_to_permit += %w"organization_id superadmin" if superadmin?
     fields_to_permit += %w"password" if params[:from_signup].present?
 
@@ -144,13 +139,13 @@ def redirect_to_after_create
       if params[:more]
         redirect_to new_user_path,
                     notice: I18n.t("users.new.user_created_add",
-                                   uid: id,
-                                   name: @user.username)
+                                  uid: id,
+                                  name: @user.username)
       else
         redirect_to users_path,
                     notice: I18n.t("users.index.user_created",
-                                   uid: id,
-                                   name: @user.username)
+                                  uid: id,
+                                  name: @user.username)
       end
     end
   end
diff --git a/app/decorators/member_decorator.rb b/app/decorators/member_decorator.rb
index f522da9b1..c3d0aaefe 100644
--- a/app/decorators/member_decorator.rb
+++ b/app/decorators/member_decorator.rb
@@ -7,11 +7,11 @@ def manager?
   end
 
   def row_css_class
-    "bg-danger" unless active?
+    'bg-danger' unless active?
   end
 
   def inactive_icon
-    view.glyph("time") unless active?
+    view.glyph('time') unless active?
   end
 
   def link_to_self
@@ -20,7 +20,7 @@ def link_to_self
 
   def mail_to
     email = user.unconfirmed_email || user.email
-    view.mail_to(email) if email && !email.end_with?("example.com")
+    view.mail_to(email) if email && !email.end_with?('example.com')
   end
 
   def account_balance
diff --git a/app/decorators/report/transfer_decorator.rb b/app/decorators/report/transfer_decorator.rb
index 323bfea53..305a4dcdc 100644
--- a/app/decorators/report/transfer_decorator.rb
+++ b/app/decorators/report/transfer_decorator.rb
@@ -1,8 +1,7 @@
 class Report::TransferDecorator
   include Rails.application.routes.url_helpers
   include ActionView::Helpers
-  include TransfersHelper
-  include ApplicationHelper
+  include ApplicationHelper, TransfersHelper
 
   def initialize(org, collection)
     @org = org
@@ -18,11 +17,11 @@ def name(extension)
 
   def headers
     [
-      I18n.t("statistics.all_transfers.date"),
-      I18n.t("statistics.all_transfers.from"),
-      I18n.t("statistics.all_transfers.to"),
-      I18n.t("statistics.all_transfers.post"),
-      I18n.t("statistics.all_transfers.quantity")
+      I18n.t('statistics.all_transfers.date'),
+      I18n.t('statistics.all_transfers.from'),
+      I18n.t('statistics.all_transfers.to'),
+      I18n.t('statistics.all_transfers.post'),
+      I18n.t('statistics.all_transfers.quantity')
     ]
   end
 
diff --git a/app/decorators/view_model.rb b/app/decorators/view_model.rb
index ee45101bf..8de925637 100644
--- a/app/decorators/view_model.rb
+++ b/app/decorators/view_model.rb
@@ -26,7 +26,7 @@
 #
 # From controllers, one can pass `self.class.helpers`, and from tests it is
 # enough to use ApplicationController.new.view_context.
-#
+# 
 class ViewModel
   attr_reader :object, :view, :routes
 
@@ -36,3 +36,4 @@ def initialize(object, view)
     @routes = Rails.application.routes.url_helpers
   end
 end
+
diff --git a/app/helpers/active_admin_helper.rb b/app/helpers/active_admin_helper.rb
index ea899b730..8e43496a7 100644
--- a/app/helpers/active_admin_helper.rb
+++ b/app/helpers/active_admin_helper.rb
@@ -1,8 +1,8 @@
 module ActiveAdminHelper
   def render_translations(attribute, joiner = " | ")
-    attribute.map do |locale, translation|
+     attribute.map do |locale, translation|
       tag.strong("#{I18n.t("locales.#{locale}", locale: locale)}: ") +
-        tag.span(translation)
+      tag.span(translation)
     end.join(joiner).html_safe
   end
 end
diff --git a/app/helpers/application_helper.rb b/app/helpers/application_helper.rb
index b655d9407..5fe37cdd8 100644
--- a/app/helpers/application_helper.rb
+++ b/app/helpers/application_helper.rb
@@ -1,17 +1,15 @@
 module ApplicationHelper
-  TEXT_SUCCESS = "text-success".freeze
-  TEXT_DANGER = "text-danger".freeze
+  TEXT_SUCCESS = 'text-success'.freeze
+  TEXT_DANGER = 'text-danger'.freeze
 
   def page_title
-    current_organization || "TimeOverflow"
+    current_organization || 'TimeOverflow'
   end
 
   def avatar_url(user, size = 32)
-    if user.avatar.attached?
-      user.avatar.variant(resize: "#{size}x#{size}")
-    else
+    user.avatar.attached? ?
+      user.avatar.variant(resize: "#{size}x#{size}") :
       gravatar_url(user, size)
-    end
   end
 
   def gravatar_url(user, size = 32)
@@ -78,7 +76,7 @@ def show_error_messages!(resource)
   # Content can be nil, in that case
   # it will be the same as an empty string.
   def markdown(content)
-    RDiscount.new(content || "".freeze).to_html.html_safe
+    RDiscount.new(content || ''.freeze).to_html.html_safe
   end
   alias m markdown
 
@@ -94,12 +92,12 @@ def green_red(amount)
 
   def get_body_css_class(controller)
     classes = {
-      "home" => "landing-page",
-      "sessions" => "login-page",
-      "pages" => "pages",
-      "unlocks" => "unlocks-page",
-      "passwords" => "passwords-page",
-      "confirmations" => "confirmations-page"
+      'home' => 'landing-page',
+      'sessions' => 'login-page',
+      'pages' => 'pages',
+      'unlocks' => 'unlocks-page',
+      'passwords' => 'passwords-page',
+      'confirmations' => 'confirmations-page'
     }
 
     "#{classes[controller]}"
@@ -107,12 +105,12 @@ def get_body_css_class(controller)
 
   def alert_class(alert)
     case alert
-    when "error", "alert"
-      "alert-danger"
-    when "notice"
-      "alert-success"
+    when 'error', 'alert'
+      'alert-danger'
+    when 'notice'
+      'alert-success'
     else
-      "alert-info"
+      'alert-info'
     end
   end
 end
diff --git a/app/helpers/glyph_helper.rb b/app/helpers/glyph_helper.rb
index 56640eb71..ddff8d266 100644
--- a/app/helpers/glyph_helper.rb
+++ b/app/helpers/glyph_helper.rb
@@ -8,7 +8,7 @@ module GlyphHelper
     "organization" => "tower"
   }
 
-  def glyph(kind, title = nil)
+  def glyph(kind, title=nil)
     kind = kind.to_s.underscore
     content_tag :span, "",
                 class: "glyphicon glyphicon-#{glyph_name(kind)}",
diff --git a/app/helpers/posts_helper.rb b/app/helpers/posts_helper.rb
index 079fce2b2..bc8f14619 100644
--- a/app/helpers/posts_helper.rb
+++ b/app/helpers/posts_helper.rb
@@ -1,7 +1,7 @@
 module PostsHelper
   def members_for_select(post)
     members = current_organization.members.active.order("members.member_uid").
-              map { |mem| ["#{mem.member_uid} #{mem.user}", mem.user_id] }
+              map { |mem| ["#{mem.member_uid} #{mem.user.to_s}", mem.user_id] }
 
     options_for_select(members, selected: post.user.id || current_user.id)
   end
diff --git a/app/helpers/transfers_helper.rb b/app/helpers/transfers_helper.rb
index acf960f1a..7e6cf20f0 100644
--- a/app/helpers/transfers_helper.rb
+++ b/app/helpers/transfers_helper.rb
@@ -12,14 +12,13 @@ def accounts_from_movements(transfer, with_links: false)
       account = movement.account
 
       if account.accountable.blank?
-        I18n.t("users.show.deleted_user")
-      elsif account.accountable_type == "Organization"
+        I18n.t('users.show.deleted_user')
+      elsif account.accountable_type == 'Organization'
         link_to_if(with_links, account, organization_path(account.accountable))
       elsif account.accountable.active
-        link_to_if(with_links, account.accountable.display_name_with_uid,
-                   user_path(account.accountable.user))
+        link_to_if(with_links, account.accountable.display_name_with_uid, user_path(account.accountable.user))
       else
-        I18n.t("users.show.inactive_user")
+        I18n.t('users.show.inactive_user')
       end
     end
   end
diff --git a/app/helpers/users_helper.rb b/app/helpers/users_helper.rb
index 0c5b937c7..e0562469b 100644
--- a/app/helpers/users_helper.rb
+++ b/app/helpers/users_helper.rb
@@ -40,6 +40,6 @@ def can_toggle_active?(_member)
   end
 
   def status_applications(status)
-    t("petitions.status_applications", status: t("petitions.status.#{status}").humanize)
+    t('petitions.status_applications', status: t("petitions.status.#{status}").humanize)
   end
 end
diff --git a/app/jobs/create_push_notifications_job.rb b/app/jobs/create_push_notifications_job.rb
index 049da2bb9..64a7ab5a6 100644
--- a/app/jobs/create_push_notifications_job.rb
+++ b/app/jobs/create_push_notifications_job.rb
@@ -4,7 +4,7 @@ class CreatePushNotificationsJob < ActiveJob::Base
   def perform(event_id:)
     event = ::Event.find_by_id(event_id)
 
-    raise "A valid Event must be provided" unless event
+    raise 'A valid Event must be provided' unless event
 
     if event.post_id
       ::PushNotifications::Creator::Post.new(event: event).create!
diff --git a/app/jobs/organization_notifier_job.rb b/app/jobs/organization_notifier_job.rb
index fac2df25d..e8949bba6 100644
--- a/app/jobs/organization_notifier_job.rb
+++ b/app/jobs/organization_notifier_job.rb
@@ -27,8 +27,8 @@ def users_by_locale(organization)
     with_notifications = organization.users.online_active.actives.notifications
     org_locales = with_notifications.pluck(:locale).uniq
 
-    org_locales.index_with do |locale|
-      with_notifications.where(locale: locale)
+    org_locales.each_with_object({}) do |locale, hash|
+      hash[locale] = with_notifications.where(locale: locale)
     end
   end
 end
diff --git a/app/mailers/organization_notifier.rb b/app/mailers/organization_notifier.rb
index 6579fbcd7..d3ed1fcd5 100644
--- a/app/mailers/organization_notifier.rb
+++ b/app/mailers/organization_notifier.rb
@@ -19,7 +19,7 @@ def new_petition(petition)
 
     I18n.with_locale(locale) do
       mail(
-        subject: "New Application",
+        subject: 'New Application',
         to: organization.users.joins(:members).where(members: { manager: true }).pluck(:email).uniq
       )
     end
@@ -30,7 +30,7 @@ def petition_sent(petition)
 
     I18n.with_locale(locale) do
       mail(
-        subject: "Application sent correctly",
+        subject: 'Application sent correctly',
         to: petition.user.email
       )
     end
diff --git a/app/models/account.rb b/app/models/account.rb
index 012534264..c441349ba 100644
--- a/app/models/account.rb
+++ b/app/models/account.rb
@@ -23,7 +23,9 @@ def update_balance
   end
 
   # Print the account as its accountable reference
-  delegate :to_s, to: :accountable
+  def to_s
+    accountable.to_s
+  end
 
   protected
 
diff --git a/app/models/concerns/taggable.rb b/app/models/concerns/taggable.rb
index 2bec8aaa5..4dba82ec7 100644
--- a/app/models/concerns/taggable.rb
+++ b/app/models/concerns/taggable.rb
@@ -34,18 +34,16 @@ def tag_list
     # @return [Hash<String => Integer>]
     def tag_cloud
       Hash[
-        all_tags.
-        group_by(&:to_s).
-        map { |tag_name, values| [tag_name, values.size] }.
-        sort_by { |array| array.first.downcase }
+        all_tags
+          .group_by(&:to_s)
+          .map { |tag_name, values| [tag_name, values.size] }
+          .sort_by { |array| array.first.downcase }
       ]
     end
 
     def find_like_tag(pattern)
       transliterated_pattern = pattern.present? ? ActiveSupport::Inflector.transliterate(pattern) : ""
-      all_tags.uniq.select do |t|
-        ActiveSupport::Inflector.transliterate(t) =~ /#{transliterated_pattern}/i
-      end
+      all_tags.uniq.select { |t| ActiveSupport::Inflector.transliterate(t) =~ /#{transliterated_pattern}/i }
     end
 
     # Builds a hash where the keys are the capital letters of the tags and the
diff --git a/app/models/event.rb b/app/models/event.rb
index 0b2fd0cea..fa05bfd21 100644
--- a/app/models/event.rb
+++ b/app/models/event.rb
@@ -16,6 +16,6 @@ class Event < ApplicationRecord
   def resource_presence
     return if post_id.present? ^ member_id.present? ^ transfer_id.present?
 
-    errors.add(:base, "Specify only one resource id: `post_id`, `member_id` or `transfer_id`")
+    errors.add(:base, 'Specify only one resource id: `post_id`, `member_id` or `transfer_id`')
   end
 end
diff --git a/app/models/member.rb b/app/models/member.rb
index c97b54902..28285f486 100644
--- a/app/models/member.rb
+++ b/app/models/member.rb
@@ -27,7 +27,7 @@ class Member < ApplicationRecord
   delegate :balance, to: :account, prefix: true, allow_nil: true
   delegate :gender, :date_of_birth, to: :user, prefix: true, allow_nil: true
 
-  scope :by_month, ->(month) { where(created_at: month.beginning_of_month..month.end_of_month) }
+  scope :by_month, -> (month) { where(created_at: month.beginning_of_month..month.end_of_month) }
   scope :active, -> { where active: true }
   scope :by_organization, ->(org) { where(organization_id: org) if org }
 
diff --git a/app/models/movement.rb b/app/models/movement.rb
index 3cad5edde..078a427c7 100644
--- a/app/models/movement.rb
+++ b/app/models/movement.rb
@@ -9,7 +9,7 @@ class Movement < ApplicationRecord
   belongs_to :account, optional: true
   belongs_to :transfer, optional: true
 
-  scope :by_month, ->(month) { where(created_at: month.beginning_of_month..month.end_of_month) }
+  scope :by_month, -> (month) { where(created_at: month.beginning_of_month..month.end_of_month) }
 
   validates :amount, numericality: { other_than: 0 }
 
diff --git a/app/models/organization.rb b/app/models/organization.rb
index d97efc08d..cec867101 100644
--- a/app/models/organization.rb
+++ b/app/models/organization.rb
@@ -2,13 +2,13 @@ class Organization < ApplicationRecord
   include PgSearch::Model
 
   pg_search_scope :search_by_query,
-                  against: %i[city neighborhood address name],
-                  ignoring: :accents,
-                  using: {
-                    tsearch: {
-                      prefix: true
-                    }
-                  }
+    against: %i[city neighborhood address name],
+    ignoring: :accents,
+    using: {
+      tsearch: {
+        prefix: true
+      }
+    }
 
   has_one_attached :logo
 
@@ -73,7 +73,7 @@ def next_reg_number_seq
 
   def ensure_url
     return if web.blank? || URI.parse(web).is_a?(URI::HTTP)
-  rescue StandardError
+  rescue
     errors.add(:web, :url_format_invalid)
   else
     if URI.parse("http://#{web}").is_a?(URI::HTTP)
diff --git a/app/models/petition.rb b/app/models/petition.rb
index dbad7ee41..24ad28376 100644
--- a/app/models/petition.rb
+++ b/app/models/petition.rb
@@ -1,5 +1,5 @@
 class Petition < ApplicationRecord
-  enum status: { pending: 0, accepted: 1, declined: 2 }
+  enum status: %i[pending accepted declined]
 
   belongs_to :user
   belongs_to :organization
diff --git a/app/models/post.rb b/app/models/post.rb
index 0c63f5486..199755bf3 100644
--- a/app/models/post.rb
+++ b/app/models/post.rb
@@ -3,14 +3,14 @@ class Post < ApplicationRecord
   include PgSearch::Model
 
   pg_search_scope :search_by_query,
-                  against: %i[title description tags],
-                  ignoring: :accents,
-                  using: {
-                    tsearch: {
-                      prefix: true,
-                      tsvector_column: "tsv"
-                    }
-                  }
+    against: [:title, :description, :tags],
+    ignoring: :accents,
+    using: {
+      tsearch: {
+        prefix: true,
+        tsvector_column: 'tsv'
+      }
+    }
 
   attr_reader :member_id
 
@@ -47,7 +47,7 @@ class Post < ApplicationRecord
   validates :title, presence: true
 
   def as_indexed_json(*)
-    as_json(only: %i[title description tags organization_id])
+    as_json(only: [:title, :description, :tags, :organization_id])
   end
 
   def to_s
@@ -71,6 +71,6 @@ def member
   end
 
   def rendered_description
-    RDiscount.new(description || "", :autolink)
+    RDiscount.new(description || '', :autolink)
   end
 end
diff --git a/app/models/push_notification.rb b/app/models/push_notification.rb
index 26872ed82..8344537b8 100644
--- a/app/models/push_notification.rb
+++ b/app/models/push_notification.rb
@@ -1,6 +1,6 @@
 class PushNotification < ApplicationRecord
-  belongs_to :event
-  belongs_to :device_token
+  belongs_to :event, foreign_key: 'event_id'
+  belongs_to :device_token, foreign_key: 'device_token_id'
 
   validates :title, :body, presence: true, allow_blank: false
 
diff --git a/app/models/transfer.rb b/app/models/transfer.rb
index 10419f19b..41e4db8ca 100644
--- a/app/models/transfer.rb
+++ b/app/models/transfer.rb
@@ -24,8 +24,7 @@ class Transfer < ApplicationRecord
 
   def make_movements
     movements.create(account: Account.find(source_id), amount: -amount.to_i, created_at: created_at)
-    movements.create(account: Account.find(destination_id), amount: amount.to_i,
-                     created_at: created_at)
+    movements.create(account: Account.find(destination_id), amount: amount.to_i, created_at: created_at)
   end
 
   def source_id
@@ -38,7 +37,6 @@ def destination_id
 
   def different_source_and_destination
     return unless source == destination
-
     errors.add(:base, :same_account)
   end
 end
diff --git a/app/models/transfer_factory.rb b/app/models/transfer_factory.rb
index 29769d8d2..a093299cd 100644
--- a/app/models/transfer_factory.rb
+++ b/app/models/transfer_factory.rb
@@ -73,8 +73,8 @@ def admin?
   #
   # @return [Account]
   def destination_account
-    @destination_account ||= current_organization.
-                             all_accounts.
-                             find(destination_account_id)
+    @destination_account ||= current_organization
+      .all_accounts
+      .find(destination_account_id)
   end
 end
diff --git a/app/models/transfer_sources_options.rb b/app/models/transfer_sources_options.rb
index 252d5fda2..f9c2b2a9d 100644
--- a/app/models/transfer_sources_options.rb
+++ b/app/models/transfer_sources_options.rb
@@ -13,9 +13,9 @@ def initialize(sources)
   #
   # @return [Array<String, Integer>]
   def to_a
-    sources.
-      sort_by { |account| to_accountable_type_and_uid(account) }.
-      map { |account| to_text_and_value(account) }
+    sources
+      .sort_by { |account| to_accountable_type_and_uid(account) }
+      .map { |account| to_text_and_value(account) }
   end
 
   private
diff --git a/app/models/user.rb b/app/models/user.rb
index 8a3b58cd0..49f462f19 100644
--- a/app/models/user.rb
+++ b/app/models/user.rb
@@ -1,9 +1,16 @@
 class User < ApplicationRecord
-  devise :database_authenticatable, :recoverable, :rememberable, :confirmable, :lockable,
-         :trackable, :timeoutable
+  devise *[
+    :database_authenticatable,
+    :recoverable,
+    :rememberable,
+    :confirmable,
+    :lockable,
+    :trackable,
+    :timeoutable
+  ]
 
   ransacker :username do
-    Arel.sql("unaccent(users.username)")
+    Arel.sql('unaccent(users.username)')
   end
 
   GENDERS = %w(
@@ -13,7 +20,8 @@ class User < ApplicationRecord
     prefer_not_to_answer
   )
 
-  attr_accessor :empty_email, :from_signup
+  attr_accessor :empty_email
+  attr_accessor :from_signup
 
   has_one_attached :avatar
 
@@ -39,8 +47,8 @@ class User < ApplicationRecord
   validates :password, presence: true, if: :from_signup?
   # Allows @domain.com for dummy emails but does not allow pure invalid
   # emails like 'without email'
-  validates :email,
-            format: { with: /\A([^@\s]+)@((?:[-a-z0-9]+\.)+[a-z]{2,})\Z/i }
+  validates_format_of :email,
+                      with: /\A([^@\s]+)@((?:[-a-z0-9]+\.)+[a-z]{2,})\Z/i
   validates :gender, inclusion: { in: GENDERS, allow_blank: true }
 
   def as_member_of(organization)
@@ -77,7 +85,7 @@ def add_to_organization(organization)
     persister = ::Persister::MemberPersister.new(member)
     persister.save
 
-    member if member.persisted?
+    return member if member.persisted?
   end
 
   def active?(organization)
@@ -125,8 +133,7 @@ def email_if_real
   end
 
   def was_member?(petition)
-    petition.status == "accepted" && Member.where(organization: petition.organization,
-                                                  user: self).none?
+    petition.status == 'accepted' && Member.where(organization: petition.organization, user: self).none?
   end
 
   def from_signup?
diff --git a/app/services/operations/transfers.rb b/app/services/operations/transfers.rb
index 003f78c8c..8bd56a59b 100644
--- a/app/services/operations/transfers.rb
+++ b/app/services/operations/transfers.rb
@@ -11,11 +11,12 @@ def create(from:, to:, transfer_params:)
     end
 
     def transfer_klass(from:, to:)
-      if from.length == 1 && to.length == 1
+      case
+      when from.length == 1 && to.length == 1
         OneToOne
-      elsif from.length > 1 && to.length == 1
+      when from.length > 1 && to.length == 1
         ManyToOne
-      elsif from.length == 1 && to.length > 1
+      when from.length == 1 && to.length > 1
         OneToMany
       else
         raise ArgumentError, "Unknown type of transfer"
diff --git a/app/services/operations/transfers/base.rb b/app/services/operations/transfers/base.rb
index 67d265424..7950b069b 100644
--- a/app/services/operations/transfers/base.rb
+++ b/app/services/operations/transfers/base.rb
@@ -37,9 +37,9 @@ def transfers
 
       def build_transfer(source:, destination:)
         ::Transfer.new(transfer_params_for(
-                         source: source,
-                         destination: destination
-                       ))
+          source: source,
+          destination: destination
+        ))
       end
 
       def transfer_params_for(source:, destination:)
diff --git a/app/services/operations/transfers/one_to_many.rb b/app/services/operations/transfers/one_to_many.rb
index 629e749b6..f24f4e9ae 100644
--- a/app/services/operations/transfers/one_to_many.rb
+++ b/app/services/operations/transfers/one_to_many.rb
@@ -22,3 +22,4 @@ def destinations
     end
   end
 end
+
diff --git a/app/services/persister/member_persister.rb b/app/services/persister/member_persister.rb
index b790740c6..c03bcd201 100644
--- a/app/services/persister/member_persister.rb
+++ b/app/services/persister/member_persister.rb
@@ -12,7 +12,7 @@ def save
         create_save_event!
         member
       end
-    rescue ActiveRecord::RecordInvalid => _e
+    rescue ActiveRecord::RecordInvalid => _exception
       false
     end
 
@@ -22,7 +22,7 @@ def update(params)
         create_update_event!
         member
       end
-    rescue ActiveRecord::RecordInvalid => _e
+    rescue ActiveRecord::RecordInvalid => _exception
       false
     end
 
diff --git a/app/services/persister/post_persister.rb b/app/services/persister/post_persister.rb
index c9bea3a34..c5287647c 100644
--- a/app/services/persister/post_persister.rb
+++ b/app/services/persister/post_persister.rb
@@ -13,7 +13,7 @@ def save
         enqueue_push_notification_job!
         post
       end
-    rescue ActiveRecord::RecordInvalid => _e
+    rescue ActiveRecord::RecordInvalid => _exception
       false
     end
 
@@ -24,7 +24,7 @@ def update(params)
         enqueue_push_notification_job!
         post
       end
-    rescue ActiveRecord::RecordInvalid => _e
+    rescue ActiveRecord::RecordInvalid => _exception
       false
     end
 
diff --git a/app/services/persister/transfer_persister.rb b/app/services/persister/transfer_persister.rb
index c540d6f6f..2a48cfa20 100644
--- a/app/services/persister/transfer_persister.rb
+++ b/app/services/persister/transfer_persister.rb
@@ -12,7 +12,7 @@ def save
         create_save_event!
         transfer
       end
-    rescue ActiveRecord::RecordInvalid => _e
+    rescue ActiveRecord::RecordInvalid => _exception
       false
     end
 
@@ -22,7 +22,7 @@ def update(params)
         create_update_event!
         transfer
       end
-    rescue ActiveRecord::RecordInvalid => _e
+    rescue ActiveRecord::RecordInvalid => _exception
       false
     end
 
diff --git a/app/services/push_notifications/broadcast.rb b/app/services/push_notifications/broadcast.rb
index 09f07c987..9681ea9d2 100644
--- a/app/services/push_notifications/broadcast.rb
+++ b/app/services/push_notifications/broadcast.rb
@@ -46,7 +46,7 @@ def client
     end
 
     def uri
-      URI("https://exp.host/--/api/v2/push/send")
+      URI('https://exp.host/--/api/v2/push/send')
     end
 
     def headers
diff --git a/app/services/push_notifications/creator/base.rb b/app/services/push_notifications/creator/base.rb
index f08f0eef9..b7fdec805 100644
--- a/app/services/push_notifications/creator/base.rb
+++ b/app/services/push_notifications/creator/base.rb
@@ -27,15 +27,15 @@ def create!
       attr_accessor :event
 
       def title
-        raise "implement the private method `title`"
+        raise 'implement the private method `title`'
       end
 
       def body
-        raise "implement the private method `body`"
+        raise 'implement the private method `body`'
       end
 
       def data
-        raise "implement the private method `data`"
+        raise 'implement the private method `data`'
       end
     end
   end
diff --git a/app/services/push_notifications/creator/post.rb b/app/services/push_notifications/creator/post.rb
index 6a2fdf94d..66e047d6e 100644
--- a/app/services/push_notifications/creator/post.rb
+++ b/app/services/push_notifications/creator/post.rb
@@ -11,16 +11,16 @@ def body
         description = event.post.description
 
         if description.blank?
-          "No description"
+          'No description'
         else
           description.truncate(20)
         end
       end
 
       def data
-        if event.post.class.to_s == "Offer"
+        if event.post.class.to_s == 'Offer'
           { url: Rails.application.routes.url_helpers.offer_path(event.post) }
-        elsif event.post.class.to_s == "Inquiry"
+        elsif event.post.class.to_s == 'Inquiry'
           { url: Rails.application.routes.url_helpers.inquiry_path(event.post) }
         else
           {}
diff --git a/app/services/push_notifications/event_notifier/post.rb b/app/services/push_notifications/event_notifier/post.rb
index 9ed81e156..0a685c03e 100644
--- a/app/services/push_notifications/event_notifier/post.rb
+++ b/app/services/push_notifications/event_notifier/post.rb
@@ -29,12 +29,12 @@ def device_tokens
       #
       # @return <User::ActiveRecord_AssociationRelation>
       def user_ids
-        post.
-          organization.
-          users.
-          select(:id).
-          where("members.active = true").
-          where("users.push_notifications = true")
+        post
+          .organization
+          .users
+          .select(:id)
+          .where('members.active = true')
+          .where('users.push_notifications = true')
       end
     end
   end
diff --git a/app/services/push_notifications/event_notifier_factory.rb b/app/services/push_notifications/event_notifier_factory.rb
index 2f0a4e480..092583084 100644
--- a/app/services/push_notifications/event_notifier_factory.rb
+++ b/app/services/push_notifications/event_notifier_factory.rb
@@ -7,7 +7,7 @@ def initialize(event:)
     def build
       return EventNotifier::Post.new(event: event) if event.post_id
 
-      raise "The resource associated to the Event is not supported"
+      raise 'The resource associated to the Event is not supported'
     end
 
     private
diff --git a/app/services/transfer_importer.rb b/app/services/transfer_importer.rb
index 617909c51..93acbc135 100644
--- a/app/services/transfer_importer.rb
+++ b/app/services/transfer_importer.rb
@@ -15,9 +15,8 @@ class TransferImporter
     :post_id
   ) do
     def transfer_from_row(organization_id, errors)
-      source = find_account(source_id, source_type, organization_id, errors, "source")
-      destination = find_account(destination_id, destination_type, organization_id, errors,
-                                 "destination")
+      source = find_account(source_id, source_type, organization_id, errors, 'source')
+      destination = find_account(destination_id, destination_type, organization_id, errors, 'destination')
       return unless source && destination
 
       Transfer.new(
@@ -33,15 +32,14 @@ def transfer_from_row(organization_id, errors)
     private
 
     def find_account(id, type, organization_id, errors, direction)
-      acc = if type.downcase == "organization"
+      acc = if type.downcase == 'organization'
               Organization.find(organization_id).account
             else
               Member.find_by(member_uid: id, organization_id: organization_id)&.account
             end
 
       unless acc
-        errors.push(account_id: id,
-                    errors: "#{direction}_id #{id} not found in organization #{organization_id}")
+        errors.push(account_id: id, errors: "#{direction}_id #{id} not found in organization #{organization_id}")
         return false
       end
       acc
diff --git a/app/services/user_importer.rb b/app/services/user_importer.rb
index 8a9c2f1e6..b75ac273c 100644
--- a/app/services/user_importer.rb
+++ b/app/services/user_importer.rb
@@ -68,10 +68,9 @@ def member_from_row(row, user, organization, errors)
                                            entry_date: row.entry_date,
                                            user_id: user.id)
 
-      if member.errors.present?
-        errors.push(member_id: row.member_id, email: row.email,
-                    errors: member.errors.full_messages)
-      end
+      errors.push(member_id: row.member_id, email: row.email,
+                  errors: member.errors.full_messages
+                 ) if member.errors.present?
     end
   end
 end