diff --git a/app/helpers/followables_helper.rb b/app/helpers/followables_helper.rb
index ee01d9aee..52a90f156 100644
--- a/app/helpers/followables_helper.rb
+++ b/app/helpers/followables_helper.rb
@@ -14,7 +14,7 @@ module FollowablesHelper
     return unless follow.followable.present?
 
     followable = follow.followable
-    partial = followable_class_name(followable) + "_follow"
+    partial = "#{followable_class_name(followable)}_follow"
     locals = { followable_class_name(followable).to_sym => followable }
 
     render partial, locals
diff --git a/app/helpers/tracks_helper.rb b/app/helpers/tracks_helper.rb
index 305876915..8236751d5 100644
--- a/app/helpers/tracks_helper.rb
+++ b/app/helpers/tracks_helper.rb
@@ -3,7 +3,7 @@ module TracksHelper
     track_data = ""
     prefix = " data-track-event-"
     data.each do |key, value|
-      track_data = track_data + prefix + key.to_s + "=" + value + " "
+      track_data = "#{track_data}#{prefix}#{key}=#{value} "
     end
     content_for :track_event do
       track_data
diff --git a/app/helpers/verification_helper.rb b/app/helpers/verification_helper.rb
index 587e17859..3dd9123c9 100644
--- a/app/helpers/verification_helper.rb
+++ b/app/helpers/verification_helper.rb
@@ -21,6 +21,6 @@ module VerificationHelper
     data_to_mask    = match[2]
     email_provider  = match[3]
 
-    data_to_display + "*" * data_to_mask.size + "@" + email_provider
+    "#{data_to_display}#{"*" * data_to_mask.size}@#{email_provider}"
   end
 end
diff --git a/app/helpers/votes_helper.rb b/app/helpers/votes_helper.rb
index dd436ea4e..8739c2323 100644
--- a/app/helpers/votes_helper.rb
+++ b/app/helpers/votes_helper.rb
@@ -7,9 +7,9 @@ module VotesHelper
     return "0%" if debate.total_votes == 0
 
     if vote == "likes"
-      debate_percentage_of_likes(debate).to_s + "%"
+      "#{debate_percentage_of_likes(debate)}%"
     elsif vote == "dislikes"
-      (100 - debate_percentage_of_likes(debate)).to_s + "%"
+      "#{100 - debate_percentage_of_likes(debate)}%"
     end
   end
 
diff --git a/db/dev_seeds/admin_notifications.rb b/db/dev_seeds/admin_notifications.rb
index 308928d53..8823407df 100644
--- a/db/dev_seeds/admin_notifications.rb
+++ b/db/dev_seeds/admin_notifications.rb
@@ -7,7 +7,7 @@ section "Creating Admin Notifications & Templates" do
              "people will discuss & support it.",
     body_es: "Recuerda que puedes crear propuestas y los ciudadanos las debatirán y apoyarán.",
 
-    link: Setting["url"] + "/proposals",
+    link: "#{Setting["url"]}/proposals",
     segment_recipient: "administrators"
   ).deliver
 
diff --git a/spec/system/admin/homepage/homepage_spec.rb b/spec/system/admin/homepage/homepage_spec.rb
index e2ba36f7a..9a44cda7d 100644
--- a/spec/system/admin/homepage/homepage_spec.rb
+++ b/spec/system/admin/homepage/homepage_spec.rb
@@ -22,7 +22,7 @@ describe "Homepage" do
     scenario "Admin menu links to homepage path" do
       visit new_admin_widget_card_path(header_card: true)
 
-      click_link Setting["org_name"] + " Administration"
+      click_link "#{Setting["org_name"]} Administration"
 
       expect(page).to have_current_path(admin_root_path)
     end
diff --git a/spec/system/admin/site_customization/documents_spec.rb b/spec/system/admin/site_customization/documents_spec.rb
index 1b0ac771b..51d0a3f2b 100644
--- a/spec/system/admin/site_customization/documents_spec.rb
+++ b/spec/system/admin/site_customization/documents_spec.rb
@@ -58,7 +58,7 @@ describe "Documents" do
   scenario "Create" do
     visit new_admin_site_customization_document_path
 
-    attach_file("document_attachment", Rails.root + "spec/fixtures/files/logo.pdf")
+    attach_file("document_attachment", "#{Rails.root}/spec/fixtures/files/logo.pdf")
     click_button "Upload"
 
     expect(page).to have_content "Document uploaded succesfully"
diff --git a/spec/system/social_media_meta_tags_spec.rb b/spec/system/social_media_meta_tags_spec.rb
index f114c204f..448776b9d 100644
--- a/spec/system/social_media_meta_tags_spec.rb
+++ b/spec/system/social_media_meta_tags_spec.rb
@@ -33,8 +33,7 @@ describe "Social media meta tags" do
 
       expect(page).to have_property "og:title", with: meta_title
       expect(page).to have_property "article:publisher", with: url
-      expect(page).to have_property "article:author", with: "https://www.facebook.com/" +
-                                                             facebook_handle
+      expect(page).to have_property "article:author", with: "https://www.facebook.com/#{facebook_handle}"
       expect(page).to have_property "og:url", with: "#{Capybara.app_host}/"
       expect(page).to have_property "og:image", with: "#{Capybara.app_host}/social_media_icon.png"
       expect(page).to have_property "og:site_name", with: org_name