diff --git a/.rubocop.yml b/.rubocop.yml
index 53ca2ca2191..7188b0ecefe 100644
--- a/.rubocop.yml
+++ b/.rubocop.yml
@@ -355,7 +355,7 @@ Style/MultilineBlockChain:
 
 Style/MultilineBlockLayout:
   Description: 'Ensures newlines after multiline block do statements.'
-  Enabled: false
+  Enabled: true
 
 Style/MultilineIfThen:
   Description: 'Do not use then for multi-line if/unless.'
@@ -390,7 +390,7 @@ Style/NegatedWhile:
 Style/NestedTernaryOperator:
   Description: 'Use one expression per branch in a ternary operator.'
   StyleGuide: 'https://github.com/bbatsov/ruby-style-guide#no-nested-ternary'
-  Enabled: false
+  Enabled: true
 
 Style/Next:
   Description: 'Use `next` to skip iteration instead of a condition at the end.'
@@ -400,17 +400,17 @@ Style/Next:
 Style/NilComparison:
   Description: 'Prefer x.nil? to x == nil.'
   StyleGuide: 'https://github.com/bbatsov/ruby-style-guide#predicate-methods'
-  Enabled: false
+  Enabled: true
 
 Style/NonNilCheck:
   Description: 'Checks for redundant nil checks.'
   StyleGuide: 'https://github.com/bbatsov/ruby-style-guide#no-non-nil-checks'
-  Enabled: false
+  Enabled: true
 
 Style/Not:
   Description: 'Use ! instead of not.'
   StyleGuide: 'https://github.com/bbatsov/ruby-style-guide#bang-not-not'
-  Enabled: false
+  Enabled: true
 
 Style/NumericLiterals:
   Description: >-
@@ -424,7 +424,7 @@ Style/OneLineConditional:
                  Favor the ternary operator(?:) over
                  if/then/else/end constructs.
   StyleGuide: 'https://github.com/bbatsov/ruby-style-guide#ternary-operator'
-  Enabled: false
+  Enabled: true
 
 Style/OpMethod:
   Description: 'When defining binary operators, name the argument other.'
@@ -436,7 +436,7 @@ Style/ParenthesesAroundCondition:
                  Don't use parentheses around the condition of an
                  if/unless/while.
   StyleGuide: 'https://github.com/bbatsov/ruby-style-guide#no-parens-if'
-  Enabled: false
+  Enabled: true
 
 Style/PercentLiteralDelimiters:
   Description: 'Use `%`-literal delimiters consistently'
diff --git a/app/helpers/gitlab_markdown_helper.rb b/app/helpers/gitlab_markdown_helper.rb
index f8e104b0827..985def4ad66 100644
--- a/app/helpers/gitlab_markdown_helper.rb
+++ b/app/helpers/gitlab_markdown_helper.rb
@@ -29,7 +29,7 @@ module GitlabMarkdownHelper
   end
 
   def markdown(text, options={})
-    unless (@markdown and options == @options)
+    unless @markdown && options == @options
       @options = options
       gitlab_renderer = Redcarpet::Render::GitlabHTML.new(self,
                                                           user_color_scheme_class,
diff --git a/app/mailers/notify.rb b/app/mailers/notify.rb
index ee27879cf40..8fcdd3bc853 100644
--- a/app/mailers/notify.rb
+++ b/app/mailers/notify.rb
@@ -148,7 +148,7 @@ class Notify < ActionMailer::Base
     headers['References'] = message_id(model)
     headers['X-GitLab-Project'] = "#{@project.name} | " if @project
 
-    if (headers[:subject])
+    if headers[:subject]
       headers[:subject].prepend('Re: ')
     end
 
diff --git a/app/models/project_services/asana_service.rb b/app/models/project_services/asana_service.rb
index d52214cdd69..e6e16058d41 100644
--- a/app/models/project_services/asana_service.rb
+++ b/app/models/project_services/asana_service.rb
@@ -82,7 +82,7 @@ automatically inspected. Leave blank to include all branches.'
     branch_restriction = restrict_to_branch.to_s
 
     # check the branch restriction is poplulated and branch is not included
-    if branch_restriction.length > 0 && branch_restriction.index(branch) == nil
+    if branch_restriction.length > 0 && branch_restriction.index(branch).nil?
       return
     end
 
diff --git a/lib/api/helpers.rb b/lib/api/helpers.rb
index a6e77002a01..be133a2920b 100644
--- a/lib/api/helpers.rb
+++ b/lib/api/helpers.rb
@@ -20,7 +20,7 @@ module API
       identifier = sudo_identifier()
 
       # If the sudo is the current user do nothing
-      if (identifier && !(@current_user.id == identifier || @current_user.username == identifier))
+      if identifier && !(@current_user.id == identifier || @current_user.username == identifier)
         render_api_error!('403 Forbidden: Must be admin to use sudo', 403) unless @current_user.is_admin?
         @current_user = User.by_username_or_id(identifier)
         not_found!("No user id or username for: #{identifier}") if @current_user.nil?
@@ -33,7 +33,7 @@ module API
       identifier ||= params[SUDO_PARAM] ||= env[SUDO_HEADER]
 
       # Regex for integers
-      if (!!(identifier =~ /^[0-9]+$/))
+      if !!(identifier =~ /^[0-9]+$/)
         identifier.to_i
       else
         identifier
diff --git a/lib/gitlab/satellite/merge_action.rb b/lib/gitlab/satellite/merge_action.rb
index 25122666f5e..1f2e5f82dd5 100644
--- a/lib/gitlab/satellite/merge_action.rb
+++ b/lib/gitlab/satellite/merge_action.rb
@@ -97,7 +97,7 @@ module Gitlab
         in_locked_and_timed_satellite do |merge_repo|
           prepare_satellite!(merge_repo)
           update_satellite_source_and_target!(merge_repo)
-          if (merge_request.for_fork?)
+          if merge_request.for_fork?
             repository = Gitlab::Git::Repository.new(merge_repo.path)
             commits = Gitlab::Git::Commit.between(
               repository,