diff --git a/.rubocop_todo.yml b/.rubocop_todo.yml
index 4f48ae3c..49185b4b 100644
--- a/.rubocop_todo.yml
+++ b/.rubocop_todo.yml
@@ -45,14 +45,6 @@ Style/ClassAndModuleChildren:
 
 
 
-# Offense count: 58
-# Cop supports --auto-correct.
-# Configuration parameters: EnforcedStyle, SupportedStyles, UseHashRocketsWithSymbolValues.
-# SupportedStyles: ruby19, ruby19_no_mixed_keys, hash_rockets
-Style/HashSyntax:
-  Enabled: false
-
-
 # Offense count: 3
 # Configuration parameters: NamePrefix, NamePrefixBlacklist, NameWhitelist.
 # NamePrefix: is_, has_, have_
diff --git a/Rakefile b/Rakefile
index 241e4398..1c2fb947 100644
--- a/Rakefile
+++ b/Rakefile
@@ -100,4 +100,4 @@ else
 end
 
 desc 'CI test task'
-task :ci => [:default]
+task ci: [:default]
diff --git a/lib/active_model_serializers/railtie.rb b/lib/active_model_serializers/railtie.rb
index c7d6c0d1..d6843c9c 100644
--- a/lib/active_model_serializers/railtie.rb
+++ b/lib/active_model_serializers/railtie.rb
@@ -23,7 +23,7 @@ module ActiveModelSerializers
     # This hook is run after the action_controller railtie has set the configuration
     # based on the *environment* configuration and before any config/initializers are run
     # and also before eager_loading (if enabled).
-    initializer 'active_model_serializers.set_configs', :after => 'action_controller.set_configs' do
+    initializer 'active_model_serializers.set_configs', after: 'action_controller.set_configs' do
       ActiveModelSerializers.logger = Rails.configuration.action_controller.logger
       ActiveModelSerializers.config.perform_caching = Rails.configuration.action_controller.perform_caching
       # We want this hook to run after the config has been set, even if ActionController has already loaded.
diff --git a/lib/active_model_serializers/register_jsonapi_renderer.rb b/lib/active_model_serializers/register_jsonapi_renderer.rb
index 813503f5..39442959 100644
--- a/lib/active_model_serializers/register_jsonapi_renderer.rb
+++ b/lib/active_model_serializers/register_jsonapi_renderer.rb
@@ -53,7 +53,7 @@ module ActiveModelSerializers::Jsonapi
   def self.parser
     lambda do |body|
       data = JSON.parse(body)
-      data = { :_json => data } unless data.is_a?(Hash)
+      data = { _json: data } unless data.is_a?(Hash)
       data.with_indifferent_access
     end
   end
diff --git a/lib/generators/rails/serializer_generator.rb b/lib/generators/rails/serializer_generator.rb
index c564a7c9..16a47a61 100644
--- a/lib/generators/rails/serializer_generator.rb
+++ b/lib/generators/rails/serializer_generator.rb
@@ -2,11 +2,11 @@ module Rails
   module Generators
     class SerializerGenerator < NamedBase
       source_root File.expand_path('../templates', __FILE__)
-      check_class_collision :suffix => 'Serializer'
+      check_class_collision suffix: 'Serializer'
 
-      argument :attributes, :type => :array, :default => [], :banner => 'field:type field:type'
+      argument :attributes, type: :array, default: [], banner: 'field:type field:type'
 
-      class_option :parent, :type => :string, :desc => 'The parent class for the generated serializer'
+      class_option :parent, type: :string, desc: 'The parent class for the generated serializer'
 
       def create_serializer_file
         template 'serializer.rb.erb', File.join('app/serializers', class_path, "#{file_name}_serializer.rb")
diff --git a/test/action_controller/json_api/errors_test.rb b/test/action_controller/json_api/errors_test.rb
index bdc8643f..dd1249f2 100644
--- a/test/action_controller/json_api/errors_test.rb
+++ b/test/action_controller/json_api/errors_test.rb
@@ -8,12 +8,11 @@ module ActionController
           get :render_resource_with_errors
 
           expected_errors_object = {
-            :errors =>
-              [
-                { :source => { :pointer => '/data/attributes/name' }, :detail => 'cannot be nil' },
-                { :source => { :pointer => '/data/attributes/name' }, :detail => 'must be longer' },
-                { :source => { :pointer => '/data/attributes/id' }, :detail => 'must be a uuid' }
-              ]
+            errors:               [
+              { source: { pointer: '/data/attributes/name' }, detail: 'cannot be nil' },
+              { source: { pointer: '/data/attributes/name' }, detail: 'must be longer' },
+              { source: { pointer: '/data/attributes/id' }, detail: 'must be a uuid' }
+            ]
           }.to_json
           assert_equal json_reponse_body.to_json, expected_errors_object
         end
diff --git a/test/action_controller/json_api/linked_test.rb b/test/action_controller/json_api/linked_test.rb
index 6e59e4ea..efcf4d99 100644
--- a/test/action_controller/json_api/linked_test.rb
+++ b/test/action_controller/json_api/linked_test.rb
@@ -87,7 +87,7 @@ module ActionController
         setup do
           @routes = Rails.application.routes.draw do
             ActiveSupport::Deprecation.silence do
-              match ':action', :to => LinkedTestController, via: [:get, :post]
+              match ':action', to: LinkedTestController, via: [:get, :post]
             end
           end
         end
diff --git a/test/active_model_serializers/key_transform_test.rb b/test/active_model_serializers/key_transform_test.rb
index d6e9e637..2cd91cfc 100644
--- a/test/active_model_serializers/key_transform_test.rb
+++ b/test/active_model_serializers/key_transform_test.rb
@@ -5,16 +5,16 @@ class ActiveModelSerializers::KeyTransformTest < ActiveSupport::TestCase
     obj = Object.new
     scenarios = [
       {
-        value: { :"some-key" => 'value' },
-        expected: { :SomeKey => 'value' }
+        value: { "some-key": 'value' },
+        expected: { SomeKey: 'value' }
       },
       {
-        value: { :someKey => 'value' },
-        expected: { :SomeKey => 'value' }
+        value: { someKey: 'value' },
+        expected: { SomeKey: 'value' }
       },
       {
-        value: { :some_key => 'value' },
-        expected: { :SomeKey => 'value' }
+        value: { some_key: 'value' },
+        expected: { SomeKey: 'value' }
       },
       {
         value: { 'some-key' => 'value' },
@@ -71,16 +71,16 @@ class ActiveModelSerializers::KeyTransformTest < ActiveSupport::TestCase
     obj = Object.new
     scenarios = [
       {
-        value: { :"some-key" => 'value' },
-        expected: { :someKey => 'value' }
+        value: { "some-key": 'value' },
+        expected: { someKey: 'value' }
       },
       {
-        value: { :SomeKey => 'value' },
-        expected: { :someKey => 'value' }
+        value: { SomeKey: 'value' },
+        expected: { someKey: 'value' }
       },
       {
-        value: { :some_key => 'value' },
-        expected: { :someKey => 'value' }
+        value: { some_key: 'value' },
+        expected: { someKey: 'value' }
       },
       {
         value: { 'some-key' => 'value' },
@@ -137,24 +137,24 @@ class ActiveModelSerializers::KeyTransformTest < ActiveSupport::TestCase
     obj = Object.new
     scenarios = [
       {
-        value: { :some_key => 'value' },
-        expected: { :"some-key" => 'value' }
+        value: { some_key: 'value' },
+        expected: { "some-key": 'value' }
       },
       {
         value: { 'some_key' => 'value' },
         expected: { 'some-key' => 'value' }
       },
       {
-        value: { :SomeKey => 'value' },
-        expected: { :"some-key" => 'value' }
+        value: { SomeKey: 'value' },
+        expected: { "some-key": 'value' }
       },
       {
         value: { 'SomeKey' => 'value' },
         expected: { 'some-key' => 'value' }
       },
       {
-        value: { :someKey => 'value' },
-        expected: { :"some-key" => 'value' }
+        value: { someKey: 'value' },
+        expected: { "some-key": 'value' }
       },
       {
         value: { 'someKey' => 'value' },
@@ -199,24 +199,24 @@ class ActiveModelSerializers::KeyTransformTest < ActiveSupport::TestCase
     obj = Object.new
     scenarios = [
       {
-        value: { :"some-key" => 'value' },
-        expected: { :some_key => 'value' }
+        value: { "some-key": 'value' },
+        expected: { some_key: 'value' }
       },
       {
         value: { 'some-key' => 'value' },
         expected: { 'some_key' => 'value' }
       },
       {
-        value: { :SomeKey => 'value' },
-        expected: { :some_key => 'value' }
+        value: { SomeKey: 'value' },
+        expected: { some_key: 'value' }
       },
       {
         value: { 'SomeKey' => 'value' },
         expected: { 'some_key' => 'value' }
       },
       {
-        value: { :someKey => 'value' },
-        expected: { :some_key => 'value' }
+        value: { someKey: 'value' },
+        expected: { some_key: 'value' }
       },
       {
         value: { 'someKey' => 'value' },
diff --git a/test/active_model_serializers/register_jsonapi_renderer_test_isolated.rb b/test/active_model_serializers/register_jsonapi_renderer_test_isolated.rb
index 14e32535..9ba79e22 100644
--- a/test/active_model_serializers/register_jsonapi_renderer_test_isolated.rb
+++ b/test/active_model_serializers/register_jsonapi_renderer_test_isolated.rb
@@ -44,7 +44,7 @@ class JsonApiRendererTest < ActionDispatch::IntegrationTest
 
       Rails.application.routes.draw do
         ActiveSupport::Deprecation.silence do
-          match ':action', :to => TestController, via: [:get, :post]
+          match ':action', to: TestController, via: [:get, :post]
         end
       end
     end
@@ -95,7 +95,7 @@ class JsonApiRendererTest < ActionDispatch::IntegrationTest
 
       Rails.application.routes.draw do
         ActiveSupport::Deprecation.silence do
-          match ':action', :to => TestController, via: [:get, :post]
+          match ':action', to: TestController, via: [:get, :post]
         end
       end
     end
diff --git a/test/adapter/json/transform_test.rb b/test/adapter/json/transform_test.rb
index acef81f9..e99c77a3 100644
--- a/test/adapter/json/transform_test.rb
+++ b/test/adapter/json/transform_test.rb
@@ -63,7 +63,7 @@ module ActiveModelSerializers
         def test_transform_dash
           mock_request(:dash)
           assert_equal({
-                         blog: { id: 1, :"special-attribute" => 'neat', articles: nil }
+                         blog: { id: 1, "special-attribute": 'neat', articles: nil }
                        }, @adapter.serializable_hash)
         end
 
diff --git a/test/adapter/json_api/errors_test.rb b/test/adapter/json_api/errors_test.rb
index fc44ffd0..cae7a5a6 100644
--- a/test/adapter/json_api/errors_test.rb
+++ b/test/adapter/json_api/errors_test.rb
@@ -23,7 +23,7 @@ module ActiveModelSerializers
           assert_equal serializable_resource.serializer_instance.object, @resource
 
           expected_errors_object = {
-            :errors => [
+            errors: [
               {
                 source: { pointer: '/data/attributes/name' },
                 detail: 'cannot be nil'
@@ -48,10 +48,10 @@ module ActiveModelSerializers
           assert_equal serializable_resource.serializer_instance.object, @resource
 
           expected_errors_object = {
-            :errors => [
-              { :source => { :pointer => '/data/attributes/name' }, :detail => 'cannot be nil' },
-              { :source => { :pointer => '/data/attributes/name' }, :detail => 'must be longer' },
-              { :source => { :pointer => '/data/attributes/id' }, :detail => 'must be a uuid' }
+            errors: [
+              { source: { pointer: '/data/attributes/name' }, detail: 'cannot be nil' },
+              { source: { pointer: '/data/attributes/name' }, detail: 'must be longer' },
+              { source: { pointer: '/data/attributes/id' }, detail: 'must be a uuid' }
             ]
           }
           assert_equal serializable_resource.as_json, expected_errors_object
diff --git a/test/adapter/json_api/linked_test.rb b/test/adapter/json_api/linked_test.rb
index b5d79ba0..159e2bec 100644
--- a/test/adapter/json_api/linked_test.rb
+++ b/test/adapter/json_api/linked_test.rb
@@ -370,7 +370,7 @@ module ActiveModelSerializers
           expected = [
             type: 'nested-posts', id: '2',
             relationships: {
-              :"nested-posts" => {
+              "nested-posts": {
                 data: [
                   { type: 'nested-posts', id: '1' },
                   { type: 'nested-posts', id: '2' }
diff --git a/test/adapter/json_api/links_test.rb b/test/adapter/json_api/links_test.rb
index 6be6ead6..3d22a36a 100644
--- a/test/adapter/json_api/links_test.rb
+++ b/test/adapter/json_api/links_test.rb
@@ -82,10 +82,10 @@ module ActiveModelSerializers
               }
             },
             author: 'http://example.com/link_authors/1337',
-            :"link-authors" => 'http://example.com/link_authors',
+            "link-authors": 'http://example.com/link_authors',
             resource: 'http://example.com/resource',
             posts: 'http://example.com/link_authors/1337/posts',
-            :"yet-another" => 'http://example.com/resource/1337'
+            "yet-another": 'http://example.com/resource/1337'
           }
           assert_equal(expected, hash[:data][:links])
         end
diff --git a/test/adapter/json_api/resource_meta_test.rb b/test/adapter/json_api/resource_meta_test.rb
index 5b58db9f..147309ae 100644
--- a/test/adapter/json_api/resource_meta_test.rb
+++ b/test/adapter/json_api/resource_meta_test.rb
@@ -54,7 +54,7 @@ module ActiveModel
               adapter: :json_api
             ).serializable_hash
             expected = {
-              :"comments-count" => @post.comments.count
+              "comments-count": @post.comments.count
             }
             assert_equal(expected, hash[:data][:meta])
           end
@@ -68,9 +68,9 @@ module ActiveModel
               adapter: :json_api
             ).serializable_hash
             expected = {
-              :data => [
-                { :id => '1337', :type => 'posts', :meta => { :"comments-count" => 0 } },
-                { :id => '1339', :type => 'posts', :meta => { :"comments-count" => 1 } }
+              data: [
+                { id: '1337', type: 'posts', meta: { "comments-count": 0 } },
+                { id: '1339', type: 'posts', meta: { "comments-count": 1 } }
               ]
             }
             assert_equal(expected, hash)
diff --git a/test/adapter/json_api/transform_test.rb b/test/adapter/json_api/transform_test.rb
index 217e6599..3b6e6849 100644
--- a/test/adapter/json_api/transform_test.rb
+++ b/test/adapter/json_api/transform_test.rb
@@ -76,7 +76,7 @@ module ActiveModelSerializers
                            attributes: {
                              title: 'Title 1',
                              body: 'Body 1',
-                             :"publish-at" => @publish_at
+                             "publish-at": @publish_at
                            },
                            relationships: {
                              author: {
@@ -91,10 +91,10 @@ module ActiveModelSerializers
                            },
                            links: {
                              self: 'http://example.com/posts/1337',
-                             :"post-authors" => 'http://example.com/posts/1337/authors',
-                             :"subscriber-comments" => 'http://example.com/posts/1337/comments'
+                             "post-authors": 'http://example.com/posts/1337/authors',
+                             "subscriber-comments": 'http://example.com/posts/1337/comments'
                            },
-                           meta: { rating: 5, :"favorite-count" => 10 }
+                           meta: { rating: 5, "favorite-count": 10 }
                          }
                        }, result)
         end
@@ -185,7 +185,7 @@ module ActiveModelSerializers
                            attributes: {
                              title: 'Title 1',
                              body: 'Body 1',
-                             :"publish-at" => @publish_at
+                             "publish-at": @publish_at
                            },
                            relationships: {
                              author: {
@@ -200,10 +200,10 @@ module ActiveModelSerializers
                            },
                            links: {
                              self: 'http://example.com/posts/1337',
-                             :"post-authors" => 'http://example.com/posts/1337/authors',
-                             :"subscriber-comments" => 'http://example.com/posts/1337/comments'
+                             "post-authors": 'http://example.com/posts/1337/authors',
+                             "subscriber-comments": 'http://example.com/posts/1337/comments'
                            },
-                           meta: { rating: 5, :"favorite-count" => 10 }
+                           meta: { rating: 5, "favorite-count": 10 }
                          }
                        }, result)
         end
@@ -332,14 +332,14 @@ module ActiveModelSerializers
           adapter = ActiveModelSerializers::Adapter::JsonApi.new(serializer, @options)
           result = adapter.serializable_hash
           expected_errors_object = {
-            :errors => [
+            errors: [
               {
-                :source => { :pointer => '/data/attributes/published-at' },
-                :detail => 'must be in the future'
+                source: { pointer: '/data/attributes/published-at' },
+                detail: 'must be in the future'
               },
               {
-                :source => { :pointer => '/data/attributes/title' },
-                :detail => 'must be longer'
+                source: { pointer: '/data/attributes/title' },
+                detail: 'must be longer'
               }
             ]
           }
@@ -357,14 +357,14 @@ module ActiveModelSerializers
             adapter.serializable_hash
           end
           expected_errors_object = {
-            :Errors => [
+            Errors: [
               {
-                :Source => { :Pointer => '/data/attributes/PublishedAt' },
-                :Detail => 'must be in the future'
+                Source: { Pointer: '/data/attributes/PublishedAt' },
+                Detail: 'must be in the future'
               },
               {
-                :Source => { :Pointer => '/data/attributes/Title' },
-                :Detail => 'must be longer'
+                Source: { Pointer: '/data/attributes/Title' },
+                Detail: 'must be longer'
               }
             ]
           }
@@ -382,14 +382,14 @@ module ActiveModelSerializers
             adapter.serializable_hash
           end
           expected_errors_object = {
-            :Errors => [
+            Errors: [
               {
-                :Source => { :Pointer => '/data/attributes/PublishedAt' },
-                :Detail => 'must be in the future'
+                Source: { Pointer: '/data/attributes/PublishedAt' },
+                Detail: 'must be in the future'
               },
               {
-                :Source => { :Pointer => '/data/attributes/Title' },
-                :Detail => 'must be longer'
+                Source: { Pointer: '/data/attributes/Title' },
+                Detail: 'must be longer'
               }
             ]
           }
@@ -408,14 +408,14 @@ module ActiveModelSerializers
           result = adapter.serializable_hash
 
           expected_errors_object = {
-            :errors => [
+            errors: [
               {
-                :source => { :pointer => '/data/attributes/published-at' },
-                :detail => 'must be in the future'
+                source: { pointer: '/data/attributes/published-at' },
+                detail: 'must be in the future'
               },
               {
-                :source => { :pointer => '/data/attributes/title' },
-                :detail => 'must be longer'
+                source: { pointer: '/data/attributes/title' },
+                detail: 'must be longer'
               }
             ]
           }
@@ -434,9 +434,9 @@ module ActiveModelSerializers
           result = adapter.serializable_hash
 
           expected_errors_object = {
-            :errors => [
-              { :source => { :pointer => '/data/attributes/published_at' }, :detail => 'must be in the future' },
-              { :source => { :pointer => '/data/attributes/title' }, :detail => 'must be longer' }
+            errors: [
+              { source: { pointer: '/data/attributes/published_at' }, detail: 'must be in the future' },
+              { source: { pointer: '/data/attributes/title' }, detail: 'must be longer' }
             ]
           }
           assert_equal expected_errors_object, result
@@ -470,9 +470,9 @@ module ActiveModelSerializers
           result = adapter.serializable_hash
 
           expected_errors_object = {
-            :Errors => [
-              { :Source => { :Pointer => '/data/attributes/PublishedAt' }, :Detail => 'must be in the future' },
-              { :Source => { :Pointer => '/data/attributes/Title' }, :Detail => 'must be longer' }
+            Errors: [
+              { Source: { Pointer: '/data/attributes/PublishedAt' }, Detail: 'must be in the future' },
+              { Source: { Pointer: '/data/attributes/Title' }, Detail: 'must be longer' }
             ]
           }
           assert_equal expected_errors_object, result
@@ -490,9 +490,9 @@ module ActiveModelSerializers
           result = adapter.serializable_hash
 
           expected_errors_object = {
-            :errors => [
-              { :source => { :pointer => '/data/attributes/publishedAt' }, :detail => 'must be in the future' },
-              { :source => { :pointer => '/data/attributes/title' }, :detail => 'must be longer' }
+            errors: [
+              { source: { pointer: '/data/attributes/publishedAt' }, detail: 'must be in the future' },
+              { source: { pointer: '/data/attributes/title' }, detail: 'must be longer' }
             ]
           }
           assert_equal expected_errors_object, result
diff --git a/test/serializable_resource_test.rb b/test/serializable_resource_test.rb
index 69849ac5..3df71a17 100644
--- a/test/serializable_resource_test.rb
+++ b/test/serializable_resource_test.rb
@@ -51,8 +51,8 @@ module ActiveModelSerializers
           }
         )
         expected_response_document = {
-          :errors => [
-            { :source => { :pointer => '/data/attributes/name' }, :detail => 'must be awesome' }
+          errors: [
+            { source: { pointer: '/data/attributes/name' }, detail: 'must be awesome' }
           ]
         }
         assert_equal serializable_resource.as_json(options), expected_response_document
@@ -72,8 +72,8 @@ module ActiveModelSerializers
           }
         )
         expected_response_document = {
-          :errors => [
-            { :source => { :pointer => '/data/attributes/title' }, :detail => 'must be amazing' }
+          errors: [
+            { source: { pointer: '/data/attributes/title' }, detail: 'must be amazing' }
           ]
         }
         assert_equal serializable_resource.as_json(options), expected_response_document
diff --git a/test/serializers/associations_test.rb b/test/serializers/associations_test.rb
index 218e0d72..9032f31c 100644
--- a/test/serializers/associations_test.rb
+++ b/test/serializers/associations_test.rb
@@ -143,12 +143,12 @@ module ActiveModel
         )
         actual = serializable(post, adapter: :attributes, serializer: InlineAssociationTestPostSerializer).as_json
         expected = {
-          :comments => [
-            { :id => 1, :contents => 'first comment' },
-            { :id => 2, :contents => 'last comment' }
+          comments: [
+            { id: 1, contents: 'first comment' },
+            { id: 2, contents: 'last comment' }
           ],
-          :last_comments => [
-            { :id => 2, :contents => 'last comment' }
+          last_comments: [
+            { id: 2, contents: 'last comment' }
           ]
         }
 
diff --git a/test/serializers/attribute_test.rb b/test/serializers/attribute_test.rb
index 5a914495..b0f97763 100644
--- a/test/serializers/attribute_test.rb
+++ b/test/serializers/attribute_test.rb
@@ -22,7 +22,7 @@ module ActiveModel
         inherited_klass = Class.new(AlternateBlogSerializer)
         blog_serializer = inherited_klass.new(@blog)
         adapter = ActiveModelSerializers::Adapter::Attributes.new(blog_serializer)
-        assert_equal({ :id => 1, :title => 'AMS Hints' }, adapter.serializable_hash)
+        assert_equal({ id: 1, title: 'AMS Hints' }, adapter.serializable_hash)
       end
 
       def test_multiple_calls_with_the_same_attribute
diff --git a/test/serializers/fieldset_test.rb b/test/serializers/fieldset_test.rb
index 38222761..5b99d57a 100644
--- a/test/serializers/fieldset_test.rb
+++ b/test/serializers/fieldset_test.rb
@@ -5,7 +5,7 @@ module ActiveModel
     class FieldsetTest < ActiveSupport::TestCase
       def test_fieldset_with_hash
         fieldset = ActiveModel::Serializer::Fieldset.new('post' => %w(id title), 'comment' => ['body'])
-        expected = { :post => [:id, :title], :comment => [:body] }
+        expected = { post: [:id, :title], comment: [:body] }
 
         assert_equal(expected, fieldset.fields)
       end