diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index c67b2c5..105e762 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -10,6 +10,7 @@ jobs:
           - "2.7"
           - "3.0"
           - "3.1"
+          - "3.2"
           - "jruby-9.3.10.0"
           - "jruby-9.4.1.0"
     steps:
diff --git a/.rubocop.yml b/.rubocop.yml
index b25d64d..cee8e01 100644
--- a/.rubocop.yml
+++ b/.rubocop.yml
@@ -1,4 +1,5 @@
 AllCops:
+  TargetRubyVersion: 2.6
   Exclude:
     - 'spec/support/*'
     - 'bin/**/*'
@@ -7,6 +8,8 @@ Style/Documentation:
   Enabled: false
 Style/FrozenStringLiteralComment:
   Enabled: false
+Style/StringLiterals:
+  EnforcedStyle: double_quotes
 Style/NumericPredicate:
   Enabled: false
 Lint/UnifiedInteger:
@@ -19,6 +22,7 @@ Style/PercentLiteralDelimiters:
 Metrics/BlockLength:
   Exclude:
     - 'spec/**/*'
+    - '*.gemspec'
 Security/MarshalLoad:
   Exclude:
     - 'lib/candy_check/play_store/discovery_repository.rb'
@@ -28,3 +32,9 @@ Style/Encoding:
   Enabled: false
 Style/ExpandPathArguments:
   Enabled: false
+Style/TrailingCommaInArrayLiteral:
+  EnforcedStyleForMultiline: comma
+Style/TrailingCommaInArguments:
+  EnforcedStyleForMultiline: comma
+Style/TrailingCommaInHashLiteral:
+  EnforcedStyleForMultiline: comma
diff --git a/.ruby-version b/.ruby-version
index ff365e0..e4604e3 100644
--- a/.ruby-version
+++ b/.ruby-version
@@ -1 +1 @@
-3.1.3
+3.2.1
diff --git a/Gemfile b/Gemfile
index f1d387a..86fffea 100644
--- a/Gemfile
+++ b/Gemfile
@@ -1,4 +1,4 @@
-source 'https://rubygems.org'
+source "https://rubygems.org"
 
 # Specify your gem's dependencies in candy_check.gemspec
 gemspec
diff --git a/Guardfile b/Guardfile
index 65daff3..2037978 100644
--- a/Guardfile
+++ b/Guardfile
@@ -2,8 +2,10 @@
 # More info at https://github.com/guard/guard#readme
 
 ## Uncomment and set this to only include directories you want to watch
-directories %w(lib spec) \
-  .select{|d| Dir.exist?(d) ? d : UI.warning("Directory #{d} does not exist")}
+directories(
+  %w(lib spec) \
+    .select { |d| Dir.exist?(d) ? d : UI.warning("Directory #{d} does not exist") },
+)
 
 ## Note: if you are using the `directories` clause above and you are not
 ## watching the project directory ('.'), then you will want to move
@@ -24,7 +26,7 @@ guard :minitest do
   # with Minitest::Spec
   watch(%r{^spec/(.*)_spec\.rb$})
   watch(%r{^lib/(.+)\.rb$})         { |m| "spec/#{m[1]}_spec.rb" }
-  watch(%r{^spec/spec_helper\.rb$}) { 'spec' }
+  watch(%r{^spec/spec_helper\.rb$}) { "spec" }
 
   # Rails 4
   # watch(%r{^app/(.+)\.rb$})                               { |m| "test/#{m[1]}_test.rb" }
diff --git a/Rakefile b/Rakefile
index eb37202..4abff26 100755
--- a/Rakefile
+++ b/Rakefile
@@ -1,12 +1,12 @@
 #!/usr/bin/env rake
 
-require 'bundler/gem_tasks'
-require 'rake/testtask'
-require 'rubocop/rake_task'
+require "bundler/gem_tasks"
+require "rake/testtask"
+require "rubocop/rake_task"
 
 Rake::TestTask.new(:spec) do |test|
-  test.test_files = FileList['spec/**/*_spec.rb']
-  test.libs << 'spec'
+  test.test_files = FileList["spec/**/*_spec.rb"]
+  test.libs << "spec"
   test.verbose = true
 end
 
diff --git a/candy_check.gemspec b/candy_check.gemspec
index c866a47..999f26b 100644
--- a/candy_check.gemspec
+++ b/candy_check.gemspec
@@ -25,20 +25,20 @@ Gem::Specification.new do |spec|
   spec.add_dependency "multi_json", "~> 1.15"
   spec.add_dependency "thor", "< 2.0"
 
+  spec.add_development_dependency "awesome_print"
   spec.add_development_dependency "bundler", "~> 2.0"
+  spec.add_development_dependency "guard"
+  spec.add_development_dependency "guard-minitest"
   spec.add_development_dependency "inch", "~> 0.7"
   spec.add_development_dependency "minitest", "~> 5.10"
   spec.add_development_dependency "minitest-around", "~> 0.4"
   spec.add_development_dependency "minitest-focus"
-  spec.add_development_dependency "rake", "~> 12.0"
-  spec.add_development_dependency "rubocop", "~> 0.48"
-  spec.add_development_dependency "timecop", "~> 0.8"
-  spec.add_development_dependency "webmock", "~> 3.0"
-  spec.add_development_dependency "vcr"
   spec.add_development_dependency "pry"
-  spec.add_development_dependency "awesome_print"
-  spec.add_development_dependency "guard"
-  spec.add_development_dependency "guard-minitest"
+  spec.add_development_dependency "rake", "~> 13.0"
+  spec.add_development_dependency "rubocop", "~> 1.46"
   spec.add_development_dependency "simplecov", "~> 0.18.0"
   spec.add_development_dependency "simplecov-lcov", "~> 0.8.0"
+  spec.add_development_dependency "timecop", "~> 0.9"
+  spec.add_development_dependency "vcr", "~> 6.1"
+  spec.add_development_dependency "webmock", "~> 3.0"
 end
diff --git a/lib/candy_check.rb b/lib/candy_check.rb
index ac8ff9c..075f359 100644
--- a/lib/candy_check.rb
+++ b/lib/candy_check.rb
@@ -1,7 +1,7 @@
-require 'candy_check/version'
-require 'candy_check/utils'
-require 'candy_check/app_store'
-require 'candy_check/play_store'
+require "candy_check/version"
+require "candy_check/utils"
+require "candy_check/app_store"
+require "candy_check/play_store"
 
 # Module to check and verify in-app receipts
 module CandyCheck
diff --git a/lib/candy_check/app_store.rb b/lib/candy_check/app_store.rb
index e4f1586..c6d56b4 100644
--- a/lib/candy_check/app_store.rb
+++ b/lib/candy_check/app_store.rb
@@ -1,11 +1,11 @@
-require 'candy_check/app_store/client'
-require 'candy_check/app_store/config'
-require 'candy_check/app_store/receipt'
-require 'candy_check/app_store/receipt_collection'
-require 'candy_check/app_store/verification'
-require 'candy_check/app_store/subscription_verification'
-require 'candy_check/app_store/verification_failure'
-require 'candy_check/app_store/verifier'
+require "candy_check/app_store/client"
+require "candy_check/app_store/config"
+require "candy_check/app_store/receipt"
+require "candy_check/app_store/receipt_collection"
+require "candy_check/app_store/verification"
+require "candy_check/app_store/subscription_verification"
+require "candy_check/app_store/verification_failure"
+require "candy_check/app_store/verifier"
 
 module CandyCheck
   # Module to request and verify a AppStore receipt
diff --git a/lib/candy_check/app_store/client.rb b/lib/candy_check/app_store/client.rb
index a1b0bd0..25c3336 100644
--- a/lib/candy_check/app_store/client.rb
+++ b/lib/candy_check/app_store/client.rb
@@ -1,5 +1,5 @@
-require 'multi_json'
-require 'net/http'
+require "multi_json"
+require "net/http"
 
 module CandyCheck
   module AppStore
@@ -7,7 +7,7 @@ module AppStore
     # servers (either sandbox or production).
     class Client
       # Mimetype for JSON objects
-      JSON_MIME_TYPE = 'application/json'.freeze
+      JSON_MIME_TYPE = "application/json".freeze
 
       # Initialize a new client bound to an endpoint
       # @param endpoint_url [String]
@@ -40,17 +40,17 @@ def build_http_connector
 
       def build_request(parameters)
         Net::HTTP::Post.new(@uri.request_uri).tap do |post|
-          post['Accept']       = JSON_MIME_TYPE
-          post['Content-Type'] = JSON_MIME_TYPE
+          post["Accept"]       = JSON_MIME_TYPE
+          post["Content-Type"] = JSON_MIME_TYPE
           post.body            = MultiJson.dump(parameters)
         end
       end
 
       def build_request_parameters(receipt_data, secret)
         {
-          'receipt-data' => receipt_data
+          "receipt-data" => receipt_data,
         }.tap do |h|
-          h['password'] = secret if secret
+          h["password"] = secret if secret
         end
       end
     end
diff --git a/lib/candy_check/app_store/config.rb b/lib/candy_check/app_store/config.rb
index 2f70c08..f2e5d24 100644
--- a/lib/candy_check/app_store/config.rb
+++ b/lib/candy_check/app_store/config.rb
@@ -5,15 +5,13 @@ class Config < Utils::Config
       # @return [Symbol] the used environment
       attr_reader :environment
 
-      # Initializes a new configuration from a hash
-      # @param attributes [Hash]
-      # @example
-      #   Config.new(
-      #     environment: :production # or :sandbox
-      #   )
-      def initialize(attributes)
-        super
-      end
+      # @!method initialize(attributes)
+      #   Initializes a new configuration from a hash
+      #   @param attributes [Hash]
+      #   @example
+      #     Config.new(
+      #       environment: :production # or :sandbox
+      #     )
 
       # @return [Boolean] if it is production environment
       def production?
diff --git a/lib/candy_check/app_store/receipt.rb b/lib/candy_check/app_store/receipt.rb
index 375843b..b071d9b 100644
--- a/lib/candy_check/app_store/receipt.rb
+++ b/lib/candy_check/app_store/receipt.rb
@@ -18,63 +18,63 @@ def initialize(attributes)
       # transaction was canceled.
       # @return [Boolean]
       def valid?
-        !has?('cancellation_date')
+        !has?("cancellation_date")
       end
 
       # The receipt's transaction id
       # @return [String]
       def transaction_id
-        read('transaction_id')
+        read("transaction_id")
       end
 
       # The receipt's original transaction id which might differ from
       # the transaction id for restored products
       # @return [String]
       def original_transaction_id
-        read('original_transaction_id')
+        read("original_transaction_id")
       end
 
       # The version number for the app
       # @return [String]
       def app_version
-        read('bvrs')
+        read("bvrs")
       end
 
       # The app's bundle identifier
       # @return [String]
       def bundle_identifier
-        read('bid')
+        read("bid")
       end
 
       # The app's identifier of the product (SKU)
       # @return [String]
       def product_id
-        read('product_id')
+        read("product_id")
       end
 
       # The app's item id of the product
       # @return [String]
       def item_id
-        read('item_id')
+        read("item_id")
       end
 
       # The quantity of the product
       # @return [Integer]
       def quantity
-        read_integer('quantity')
+        read_integer("quantity")
       end
 
       # The purchase date
       # @return [DateTime]
       def purchase_date
-        read_datetime_from_string('purchase_date')
+        read_datetime_from_string("purchase_date")
       end
 
       # The original purchase date which might differ from the
       # actual purchase date for restored products
       # @return [DateTime]
       def original_purchase_date
-        read_datetime_from_string('original_purchase_date')
+        read_datetime_from_string("original_purchase_date")
       end
 
       # The date of when Apple has canceled this transaction.
@@ -82,19 +82,19 @@ def original_purchase_date
       # the same as if no purchase had ever been made."
       # @return [DateTime]
       def cancellation_date
-        read_datetime_from_string('cancellation_date')
+        read_datetime_from_string("cancellation_date")
       end
 
       # The date of a subscription's expiration
       # @return [DateTime]
       def expires_date
-        read_datetime_from_string('expires_date')
+        read_datetime_from_string("expires_date")
       end
 
-      # rubocop:disable PredicateName
+      # rubocop:disable Naming/PredicateName
       def is_trial_period
-        # rubocop:enable PredicateName
-        read_bool('is_trial_period')
+        # rubocop:enable Naming/PredicateName
+        read_bool("is_trial_period")
       end
     end
   end
diff --git a/lib/candy_check/app_store/receipt_collection.rb b/lib/candy_check/app_store/receipt_collection.rb
index 2cd21df..fe7741a 100644
--- a/lib/candy_check/app_store/receipt_collection.rb
+++ b/lib/candy_check/app_store/receipt_collection.rb
@@ -10,9 +10,9 @@ class ReceiptCollection
       # from Apple's verification server
       # @param attributes [Array<Hash>] raw data from Apple's server
       def initialize(attributes)
-        @receipts = attributes.map {|r| Receipt.new(r) }.sort{ |a, b|
+        @receipts = attributes.map { |r| Receipt.new(r) }.sort do |a, b|
           a.purchase_date - b.purchase_date
-        }
+        end
       end
 
       # Check if the latest expiration date is passed
diff --git a/lib/candy_check/app_store/subscription_verification.rb b/lib/candy_check/app_store/subscription_verification.rb
index 2e9a615..72bdc44 100644
--- a/lib/candy_check/app_store/subscription_verification.rb
+++ b/lib/candy_check/app_store/subscription_verification.rb
@@ -24,9 +24,9 @@ def initialize(
       def call!
         verify!
         if valid?
-          build_collection(@response['latest_receipt_info'])
+          build_collection(@response["latest_receipt_info"])
         else
-          VerificationFailure.fetch(@response['status'])
+          VerificationFailure.fetch(@response["status"])
         end
       end
 
@@ -35,15 +35,15 @@ def call!
       def build_collection(latest_receipt_info)
         unless @product_ids.nil?
           latest_receipt_info = latest_receipt_info.select do |info|
-            @product_ids.include?(info['product_id'])
+            @product_ids.include?(info["product_id"])
           end
         end
         ReceiptCollection.new(latest_receipt_info)
       end
 
       def valid?
-        status_is_ok = @response['status'] == STATUS_OK
-        @response && status_is_ok && @response['latest_receipt_info']
+        status_is_ok = @response["status"] == STATUS_OK
+        @response && status_is_ok && @response["latest_receipt_info"]
       end
     end
   end
diff --git a/lib/candy_check/app_store/verification.rb b/lib/candy_check/app_store/verification.rb
index b7536d0..90e2f4d 100644
--- a/lib/candy_check/app_store/verification.rb
+++ b/lib/candy_check/app_store/verification.rb
@@ -29,16 +29,16 @@ def initialize(endpoint_url, receipt_data, secret = nil)
       def call!
         verify!
         if valid?
-          Receipt.new(@response['receipt'])
+          Receipt.new(@response["receipt"])
         else
-          VerificationFailure.fetch(@response['status'])
+          VerificationFailure.fetch(@response["status"])
         end
       end
 
       private
 
       def valid?
-        @response && @response['status'] == STATUS_OK && @response['receipt']
+        @response && @response["status"] == STATUS_OK && @response["receipt"]
       end
 
       def verify!
diff --git a/lib/candy_check/app_store/verification_failure.rb b/lib/candy_check/app_store/verification_failure.rb
index cb11bf0..3a1fde4 100644
--- a/lib/candy_check/app_store/verification_failure.rb
+++ b/lib/candy_check/app_store/verification_failure.rb
@@ -31,7 +31,7 @@ def fetch(code)
         private
 
         def fallback(code)
-          new(code || -1, 'Unknown error')
+          new(code || -1, "Unknown error")
         end
 
         def known
@@ -47,27 +47,27 @@ def freeze!
         end
       end
 
-      add 21_000, 'The request to the App Store was not made using' \
-                  ' the HTTP POST request method.'
-      add 21_001, 'This status code is no longer sent by the App Store.'
-      add 21_002, 'The data in the receipt-data property was malformed' \
-                  ' or the service experienced a temporary issue. Try again.'
-      add 21_003, 'The receipt could not be authenticated.'
-      add 21_004, 'The shared secret you provided does not match the shared' \
-                  ' secret on file for your account.'
-      add 21_005, 'The receipt server was temporarily unable to provide' \
-                  ' the receipt. Try again.'
-      add 21_006, 'This receipt is valid but the subscription has expired.' \
-                  ' When this status code is returned to your server, the' \
-                  ' receipt data is also decoded and returned as part of' \
-                  ' the response. Only returned for iOS 6-style transaction' \
-                  ' receipts for auto-renewable subscriptions.'
-      add 21_007, 'This receipt is from the test environment, but it was' \
-                  ' sent to the production environment for verification.'
-      add 21_008, 'This receipt is from the production environment, but it' \
-                  ' was sent to the test environment for verification.'
-      add 21_009, 'Internal data access error. Try again later.'
-      add 21_010, 'The user account cannot be found or has been deleted.'
+      add 21_000, "The request to the App Store was not made using" \
+                  " the HTTP POST request method."
+      add 21_001, "This status code is no longer sent by the App Store."
+      add 21_002, "The data in the receipt-data property was malformed" \
+                  " or the service experienced a temporary issue. Try again."
+      add 21_003, "The receipt could not be authenticated."
+      add 21_004, "The shared secret you provided does not match the shared" \
+                  " secret on file for your account."
+      add 21_005, "The receipt server was temporarily unable to provide" \
+                  " the receipt. Try again."
+      add 21_006, "This receipt is valid but the subscription has expired." \
+                  " When this status code is returned to your server, the" \
+                  " receipt data is also decoded and returned as part of" \
+                  " the response. Only returned for iOS 6-style transaction" \
+                  " receipts for auto-renewable subscriptions."
+      add 21_007, "This receipt is from the test environment, but it was" \
+                  " sent to the production environment for verification."
+      add 21_008, "This receipt is from the production environment, but it" \
+                  " was sent to the test environment for verification."
+      add 21_009, "Internal data access error. Try again later."
+      add 21_010, "The user account cannot be found or has been deleted."
       freeze!
     end
   end
diff --git a/lib/candy_check/app_store/verifier.rb b/lib/candy_check/app_store/verifier.rb
index 283117b..596fc8c 100644
--- a/lib/candy_check/app_store/verifier.rb
+++ b/lib/candy_check/app_store/verifier.rb
@@ -4,9 +4,9 @@ module AppStore
     # The call return either an {Receipt} or a {VerificationFailure}
     class Verifier
       # HTTPS endpoint for production receipts
-      PRODUCTION_ENDPOINT = 'https://buy.itunes.apple.com/verifyReceipt'.freeze
+      PRODUCTION_ENDPOINT = "https://buy.itunes.apple.com/verifyReceipt".freeze
       # HTTPS endpoint for sandbox receipts
-      SANDBOX_ENDPOINT = 'https://sandbox.itunes.apple.com/verifyReceipt'.freeze
+      SANDBOX_ENDPOINT = "https://sandbox.itunes.apple.com/verifyReceipt".freeze
       # Status code from production endpoint when receiving a sandbox
       # receipt which occurs during the app's review process
       REDIRECT_TO_SANDBOX_CODE = 21_007
@@ -49,9 +49,8 @@ def verify_subscription(receipt_data, secret = nil, product_ids = nil)
       def fetch_receipt_information(verifier_class, args)
         default_endpoint, opposite_endpoint = endpoints
         result = call_for(verifier_class, args.dup.unshift(default_endpoint))
-        if should_retry?(result)
-          return call_for(verifier_class, args.dup.unshift(opposite_endpoint))
-        end
+        return call_for(verifier_class, args.dup.unshift(opposite_endpoint)) if should_retry?(result)
+
         result
       end
 
diff --git a/lib/candy_check/cli.rb b/lib/candy_check/cli.rb
index 1e44346..d50f3d3 100644
--- a/lib/candy_check/cli.rb
+++ b/lib/candy_check/cli.rb
@@ -1,6 +1,6 @@
-require 'candy_check/cli/app'
-require 'candy_check/cli/commands'
-require 'candy_check/cli/out'
+require "candy_check/cli/app"
+require "candy_check/cli/commands"
+require "candy_check/cli/out"
 
 module CandyCheck
   # Namespace holding the implementation of the CLI to
diff --git a/lib/candy_check/cli/app.rb b/lib/candy_check/cli/app.rb
index 6a19f94..866fbc2 100644
--- a/lib/candy_check/cli/app.rb
+++ b/lib/candy_check/cli/app.rb
@@ -35,7 +35,7 @@ def play_store(package, product_id, token)
         Commands::PlayStore.run(package, product_id, token, **options)
       end
 
-      desc "version", 'Print the gem\'s version'
+      desc "version", "Print the gem's version"
 
       def version
         Commands::Version.run
diff --git a/lib/candy_check/cli/commands.rb b/lib/candy_check/cli/commands.rb
index 39907bc..ed01f6b 100644
--- a/lib/candy_check/cli/commands.rb
+++ b/lib/candy_check/cli/commands.rb
@@ -1,7 +1,7 @@
-require 'candy_check/cli/commands/base'
-require 'candy_check/cli/commands/app_store'
-require 'candy_check/cli/commands/play_store'
-require 'candy_check/cli/commands/version'
+require "candy_check/cli/commands/base"
+require "candy_check/cli/commands/app_store"
+require "candy_check/cli/commands/play_store"
+require "candy_check/cli/commands/version"
 
 module CandyCheck
   module CLI
diff --git a/lib/candy_check/cli/commands/app_store.rb b/lib/candy_check/cli/commands/app_store.rb
index 12d43a4..fd34e64 100644
--- a/lib/candy_check/cli/commands/app_store.rb
+++ b/lib/candy_check/cli/commands/app_store.rb
@@ -25,7 +25,7 @@ def run
 
         def config
           CandyCheck::AppStore::Config.new(
-            environment: options[:environment].to_sym
+            environment: options[:environment].to_sym,
           )
         end
       end
diff --git a/lib/candy_check/cli/out.rb b/lib/candy_check/cli/out.rb
index 24aeb38..c8c5fc0 100644
--- a/lib/candy_check/cli/out.rb
+++ b/lib/candy_check/cli/out.rb
@@ -1,5 +1,3 @@
-require 'pp'
-
 module CandyCheck
   module CLI
     # A wrapper to output text information to any kind of buffer
@@ -18,7 +16,7 @@ def initialize(out = $stdout)
 
       # Prints to +out+
       # @param text [String]
-      def print(text = '')
+      def print(text = "")
         out.puts text
       end
 
diff --git a/lib/candy_check/play_store/product_acknowledgements/acknowledgement.rb b/lib/candy_check/play_store/product_acknowledgements/acknowledgement.rb
index 99733ed..a4e2b06 100644
--- a/lib/candy_check/play_store/product_acknowledgements/acknowledgement.rb
+++ b/lib/candy_check/play_store/product_acknowledgements/acknowledgement.rb
@@ -26,7 +26,8 @@ def call!
           acknowledge!
 
           CandyCheck::PlayStore::ProductAcknowledgements::Response.new(
-            result: @response[:result], error_data: @response[:error_data])
+            result: @response[:result], error_data: @response[:error_data],
+          )
         end
 
         private
diff --git a/lib/candy_check/play_store/product_purchases/product_verification.rb b/lib/candy_check/play_store/product_purchases/product_verification.rb
index 727f509..657c454 100644
--- a/lib/candy_check/play_store/product_purchases/product_verification.rb
+++ b/lib/candy_check/play_store/product_purchases/product_verification.rb
@@ -37,7 +37,7 @@ def call!
         private
 
         def valid?
-          @response[:result] && @response[:result].purchase_state && @response[:result].consumption_state
+          @response[:result]&.purchase_state && @response[:result]&.consumption_state
         end
 
         def verify!
diff --git a/lib/candy_check/play_store/subscription_purchases/subscription_purchase.rb b/lib/candy_check/play_store/subscription_purchases/subscription_purchase.rb
index 9d1068d..7ad89a3 100644
--- a/lib/candy_check/play_store/subscription_purchases/subscription_purchase.rb
+++ b/lib/candy_check/play_store/subscription_purchases/subscription_purchase.rb
@@ -5,7 +5,8 @@ module SubscriptionPurchases
       class SubscriptionPurchase
         include Utils::AttributeReader
 
-        # @return [Google::Apis::AndroidpublisherV3::SubscriptionPurchase] the raw subscription purchase from google-api-client
+        # @return [Google::Apis::AndroidpublisherV3::SubscriptionPurchase] the raw subscription purchase
+        #   from google-api-client
         attr_reader :subscription_purchase
 
         # The payment of the subscription is pending (paymentState)
diff --git a/lib/candy_check/play_store/subscription_purchases/subscription_verification.rb b/lib/candy_check/play_store/subscription_purchases/subscription_verification.rb
index 1d6eea1..48a1ba7 100644
--- a/lib/candy_check/play_store/subscription_purchases/subscription_verification.rb
+++ b/lib/candy_check/play_store/subscription_purchases/subscription_verification.rb
@@ -38,6 +38,7 @@ def call!
 
         def valid?
           return false unless @response[:result]
+
           ok_kind = @response[:result].kind == "androidpublisher#subscriptionPurchase"
           @response && @response[:result].expiry_time_millis && ok_kind
         end
diff --git a/lib/candy_check/play_store/verification_failure.rb b/lib/candy_check/play_store/verification_failure.rb
index 181b85d..3ea9da6 100644
--- a/lib/candy_check/play_store/verification_failure.rb
+++ b/lib/candy_check/play_store/verification_failure.rb
@@ -18,7 +18,7 @@ def initialize(error)
       # @return [Integer]
       def code
         Integer(error.status_code)
-      rescue
+      rescue StandardError
         -1
       end
 
diff --git a/lib/candy_check/utils.rb b/lib/candy_check/utils.rb
index f14f370..c15e955 100644
--- a/lib/candy_check/utils.rb
+++ b/lib/candy_check/utils.rb
@@ -1,2 +1,2 @@
-require 'candy_check/utils/attribute_reader'
-require 'candy_check/utils/config'
+require "candy_check/utils/attribute_reader"
+require "candy_check/utils/config"
diff --git a/lib/candy_check/utils/attribute_reader.rb b/lib/candy_check/utils/attribute_reader.rb
index ac5de3a..fefc5f3 100644
--- a/lib/candy_check/utils/attribute_reader.rb
+++ b/lib/candy_check/utils/attribute_reader.rb
@@ -1,4 +1,4 @@
-require 'date'
+require "date"
 
 module CandyCheck
   module Utils
@@ -23,7 +23,8 @@ def read_integer(field)
       def read_bool(field)
         val = read(field).to_s
         return nil unless %w(false true).include?(val)
-        val == 'true'
+
+        val == "true"
       end
 
       def read_datetime_from_string(field)
diff --git a/lib/candy_check/utils/config.rb b/lib/candy_check/utils/config.rb
index 09e8794..935db6c 100644
--- a/lib/candy_check/utils/config.rb
+++ b/lib/candy_check/utils/config.rb
@@ -26,6 +26,7 @@ def validate!
       # @raise [ArgumentError] if attribute is missing
       def validates_presence(name)
         return if send(name)
+
         raise ArgumentError, "Configuration field #{name} is missing"
       end
 
@@ -34,6 +35,7 @@ def validates_presence(name)
       # @param values [Array] of possible values
       def validates_inclusion(name, *values)
         return if values.include?(send(name))
+
         raise ArgumentError, "Configuration field #{name} should be "\
                             "one of: #{values.join(', ')}"
       end
diff --git a/spec/app_store/client_spec.rb b/spec/app_store/client_spec.rb
index 265d9fa..acc531c 100644
--- a/spec/app_store/client_spec.rb
+++ b/spec/app_store/client_spec.rb
@@ -1,12 +1,12 @@
-require 'spec_helper'
+require "spec_helper"
 
 describe CandyCheck::AppStore::Client do
-  let(:endpoint_url) { 'https://some.endpoint.com/verify' }
+  let(:endpoint_url) { "https://some.endpoint.com/verify" }
   let(:receipt_data) do
-    'some_very_long_receipt_information_which_is_normaly_base64_encoded'
+    "some_very_long_receipt_information_which_is_normaly_base64_encoded"
   end
   let(:password) do
-    'some_secret_password'
+    "some_secret_password"
   end
   let(:response) do
     '{
@@ -18,40 +18,40 @@
   end
   let(:expected) do
     {
-      'status' => 0,
-      'receipt' => {
-        'item_id' => '521129812'
-      }
+      "status" => 0,
+      "receipt" => {
+        "item_id" => "521129812",
+      },
     }
   end
 
   subject { CandyCheck::AppStore::Client.new(endpoint_url) }
 
-  describe 'valid response' do
-    it 'sends JSON and parses the JSON response without a secret' do
+  describe "valid response" do
+    it "sends JSON and parses the JSON response without a secret" do
       stub_endpoint
         .with(
           body: {
-            'receipt-data' => receipt_data
-          }
+            "receipt-data" => receipt_data,
+          },
         )
         .to_return(
-          body: response
+          body: response,
         )
       result = subject.verify(receipt_data)
       _(result).must_equal expected
     end
 
-    it 'sends JSON and parses the JSON response with a secret' do
+    it "sends JSON and parses the JSON response with a secret" do
       stub_endpoint
         .with(
           body: {
-            'receipt-data' => receipt_data,
-            'password'     => password
-          }
+            "receipt-data" => receipt_data,
+            "password" => password,
+          },
         )
         .to_return(
-          body: response
+          body: response,
         )
       result = subject.verify(receipt_data, password)
       _(result).must_equal expected
diff --git a/spec/app_store/config_spec.rb b/spec/app_store/config_spec.rb
index 42549f9..433d431 100644
--- a/spec/app_store/config_spec.rb
+++ b/spec/app_store/config_spec.rb
@@ -1,39 +1,39 @@
-require 'spec_helper'
+require "spec_helper"
 
 describe CandyCheck::AppStore::Config do
   subject { CandyCheck::AppStore::Config.new(attributes) }
 
-  describe 'valid' do
+  describe "valid" do
     let(:attributes) do
       {
-        environment: :sandbox
+        environment: :sandbox,
       }
     end
 
-    it 'returns environment' do
+    it "returns environment" do
       _(subject.environment).must_equal :sandbox
     end
 
-    it 'checks for production?' do
+    it "checks for production?" do
       _(subject.production?).must_be_false
 
       other = CandyCheck::AppStore::Config.new(
-        environment: :production
+        environment: :production,
       )
       _(other.production?).must_be_true
     end
   end
 
-  describe 'invalid' do
+  describe "invalid" do
     let(:attributes) do
       {}
     end
 
-    it 'needs an environment' do
+    it "needs an environment" do
       _(proc { subject }).must_raise ArgumentError
     end
 
-    it 'needs an included environment' do
+    it "needs an included environment" do
       attributes[:environment] = :invalid
       _(proc { subject }).must_raise ArgumentError
     end
diff --git a/spec/app_store/receipt_collection_spec.rb b/spec/app_store/receipt_collection_spec.rb
index 624a3ea..e10c5ea 100644
--- a/spec/app_store/receipt_collection_spec.rb
+++ b/spec/app_store/receipt_collection_spec.rb
@@ -1,98 +1,96 @@
-require 'spec_helper'
+require "spec_helper"
 
 describe CandyCheck::AppStore::ReceiptCollection do
   subject { CandyCheck::AppStore::ReceiptCollection.new(attributes) }
 
-  describe 'overdue subscription' do
+  describe "overdue subscription" do
     let(:attributes) do
       [{
-        'expires_date' => '2014-04-15 12:52:40 Etc/GMT',
-        'expires_date_pst' => '2014-04-15 05:52:40 America/Los_Angeles',
-        'purchase_date' => '2014-04-14 12:52:40 Etc/GMT',
-        'is_trial_period' => 'false'
+        "expires_date" => "2014-04-15 12:52:40 Etc/GMT",
+        "expires_date_pst" => "2014-04-15 05:52:40 America/Los_Angeles",
+        "purchase_date" => "2014-04-14 12:52:40 Etc/GMT",
+        "is_trial_period" => "false",
       }, {
-        'expires_date' => '2015-04-15 12:52:40 Etc/GMT',
-        'expires_date_pst' => '2015-04-15 05:52:40 America/Los_Angeles',
-        'purchase_date' => '2015-04-14 12:52:40 Etc/GMT',
-        'is_trial_period' => 'false'
+        "expires_date" => "2015-04-15 12:52:40 Etc/GMT",
+        "expires_date_pst" => "2015-04-15 05:52:40 America/Los_Angeles",
+        "purchase_date" => "2015-04-14 12:52:40 Etc/GMT",
+        "is_trial_period" => "false",
       }]
     end
 
-    it 'is expired' do
+    it "is expired" do
       _(subject.expired?).must_be_true
     end
 
-    it 'is not a trial' do
+    it "is not a trial" do
       _(subject.trial?).must_be_false
     end
 
-    it 'has positive overdue days' do
+    it "has positive overdue days" do
       overdue = subject.overdue_days
       _(overdue).must_be_instance_of Integer
       assert overdue > 0
     end
 
-    it 'has a last expires date' do
+    it "has a last expires date" do
       expected = DateTime.new(2015, 4, 15, 12, 52, 40)
       _(subject.expires_at).must_equal expected
     end
 
-    it 'is expired? at same pointin time' do
+    it "is expired? at same pointin time" do
       Timecop.freeze(Time.utc(2015, 4, 15, 12, 52, 40)) do
         _(subject.expired?).must_be_true
       end
     end
   end
 
-  describe 'unordered receipts' do
+  describe "unordered receipts" do
     let(:attributes) do
       [{
-           'expires_date' => '2015-04-15 12:52:40 Etc/GMT',
-           'expires_date_pst' => '2015-04-15 05:52:40 America/Los_Angeles',
-           'purchase_date' => '2015-04-14 12:52:40 Etc/GMT',
-           'is_trial_period' => 'false'
-       }, {
-           'expires_date' => '2014-04-15 12:52:40 Etc/GMT',
-           'expires_date_pst' => '2014-04-15 05:52:40 America/Los_Angeles',
-           'purchase_date' => '2014-04-14 12:52:40 Etc/GMT',
-           'is_trial_period' => 'false'
-       }]
+        "expires_date" => "2015-04-15 12:52:40 Etc/GMT",
+        "expires_date_pst" => "2015-04-15 05:52:40 America/Los_Angeles",
+        "purchase_date" => "2015-04-14 12:52:40 Etc/GMT",
+        "is_trial_period" => "false",
+      }, {
+        "expires_date" => "2014-04-15 12:52:40 Etc/GMT",
+        "expires_date_pst" => "2014-04-15 05:52:40 America/Los_Angeles",
+        "purchase_date" => "2014-04-14 12:52:40 Etc/GMT",
+        "is_trial_period" => "false",
+      }]
     end
 
-    it 'the expires date is the latest one in time' do
+    it "the expires date is the latest one in time" do
       expected = DateTime.new(2015, 4, 15, 12, 52, 40)
       _(subject.expires_at).must_equal expected
     end
-
   end
 
-  describe 'unexpired trial subscription' do
+  describe "unexpired trial subscription" do
     two_days_from_now = DateTime.now + 2
 
     let(:attributes) do
       [{
-        'expires_date' => '2016-04-15 12:52:40 Etc/GMT',
-        'purchase_date' => '2016-04-15 12:52:40 Etc/GMT',
-        'is_trial_period' => 'true'
+        "expires_date" => "2016-04-15 12:52:40 Etc/GMT",
+        "purchase_date" => "2016-04-15 12:52:40 Etc/GMT",
+        "is_trial_period" => "true",
       }, {
-        'expires_date' =>
-          two_days_from_now.strftime('%Y-%m-%d %H:%M:%S Etc/GMT'),
-        'purchase_date' => '2016-04-15 12:52:40 Etc/GMT',
-        'is_trial_period' => 'true'
+        "expires_date" =>
+          two_days_from_now.strftime("%Y-%m-%d %H:%M:%S Etc/GMT"),
+        "purchase_date" => "2016-04-15 12:52:40 Etc/GMT",
+        "is_trial_period" => "true",
       }]
     end
 
-    it 'has not expired' do
+    it "has not expired" do
       _(subject.expired?).must_be_false
     end
 
-    it 'it is a trial' do
+    it "it is a trial" do
       _(subject.trial?).must_be_true
     end
 
-    it 'expires in two days' do
+    it "expires in two days" do
       _(subject.overdue_days).must_equal(-2)
     end
   end
-
 end
diff --git a/spec/app_store/receipt_spec.rb b/spec/app_store/receipt_spec.rb
index 7b974d2..56a93ce 100644
--- a/spec/app_store/receipt_spec.rb
+++ b/spec/app_store/receipt_spec.rb
@@ -1,105 +1,105 @@
-require 'spec_helper'
+require "spec_helper"
 
 describe CandyCheck::AppStore::Receipt do
   subject { CandyCheck::AppStore::Receipt.new(attributes) }
 
   let(:attributes) do
     {
-      'original_purchase_date_pst' => '2015-01-08 03:40:46' \
-                                      ' America/Los_Angeles',
-      'purchase_date_ms'           => '1420803646868',
-      'unique_identifier'          => 'some_uniq_identifier_from_apple' \
-                                      '_for_this',
-      'original_transaction_id'    => 'some_original_transaction_id',
-      'bvrs'                       => '2.0',
-      'transaction_id'             => 'some_transaction_id',
-      'quantity'                   => '1',
-      'unique_vendor_identifier'   => '00000000-1111-2222-3333-' \
-                                      '444444444444',
-      'item_id'                    => 'some_item_id',
-      'product_id'                 => 'some_product',
-      'purchase_date'              => '2015-01-09 11:40:46 Etc/GMT',
-      'original_purchase_date'     => '2015-01-08 11:40:46 Etc/GMT',
-      'purchase_date_pst'          => '2015-01-09 03:40:46' \
-                                      ' America/Los_Angeles',
-      'bid'                        => 'some.test.app',
-      'original_purchase_date_ms'  => '1420717246868',
-      'expires_date'               => '2016-06-09 13:59:40 Etc/GMT',
-      'is_trial_period'            => 'false'
+      "original_purchase_date_pst" => "2015-01-08 03:40:46" \
+                                      " America/Los_Angeles",
+      "purchase_date_ms" => "1420803646868",
+      "unique_identifier" => "some_uniq_identifier_from_apple" \
+                                      "_for_this",
+      "original_transaction_id" => "some_original_transaction_id",
+      "bvrs" => "2.0",
+      "transaction_id" => "some_transaction_id",
+      "quantity" => "1",
+      "unique_vendor_identifier" => "00000000-1111-2222-3333-" \
+                                      "444444444444",
+      "item_id" => "some_item_id",
+      "product_id" => "some_product",
+      "purchase_date" => "2015-01-09 11:40:46 Etc/GMT",
+      "original_purchase_date" => "2015-01-08 11:40:46 Etc/GMT",
+      "purchase_date_pst" => "2015-01-09 03:40:46" \
+                                      " America/Los_Angeles",
+      "bid" => "some.test.app",
+      "original_purchase_date_ms" => "1420717246868",
+      "expires_date" => "2016-06-09 13:59:40 Etc/GMT",
+      "is_trial_period" => "false",
     }
   end
 
-  describe 'valid transaction' do
-    it 'is valid' do
+  describe "valid transaction" do
+    it "is valid" do
       _(subject.valid?).must_be_true
     end
 
-    it 'returns the item\'s id' do
-      _(subject.item_id).must_equal 'some_item_id'
+    it "returns the item's id" do
+      _(subject.item_id).must_equal "some_item_id"
     end
 
-    it 'returns the item\'s product_id' do
-      _(subject.product_id).must_equal 'some_product'
+    it "returns the item's product_id" do
+      _(subject.product_id).must_equal "some_product"
     end
 
-    it 'returns the quantity' do
+    it "returns the quantity" do
       _(subject.quantity).must_equal 1
     end
 
-    it 'returns the app version' do
-      _(subject.app_version).must_equal '2.0'
+    it "returns the app version" do
+      _(subject.app_version).must_equal "2.0"
     end
 
-    it 'returns the bundle identifier' do
-      _(subject.bundle_identifier).must_equal 'some.test.app'
+    it "returns the bundle identifier" do
+      _(subject.bundle_identifier).must_equal "some.test.app"
     end
 
-    it 'returns the purchase date' do
+    it "returns the purchase date" do
       expected = DateTime.new(2015, 1, 9, 11, 40, 46)
       _(subject.purchase_date).must_equal expected
     end
 
-    it 'returns the original purchase date' do
+    it "returns the original purchase date" do
       expected = DateTime.new(2015, 1, 8, 11, 40, 46)
       _(subject.original_purchase_date).must_equal expected
     end
 
-    it 'returns the transaction id' do
-      _(subject.transaction_id).must_equal 'some_transaction_id'
+    it "returns the transaction id" do
+      _(subject.transaction_id).must_equal "some_transaction_id"
     end
 
-    it 'returns the original transaction id' do
-      _(subject.original_transaction_id).must_equal 'some_original_transaction_id'
+    it "returns the original transaction id" do
+      _(subject.original_transaction_id).must_equal "some_original_transaction_id"
     end
 
-    it 'return nil for cancellation date' do
+    it "return nil for cancellation date" do
       _(subject.cancellation_date).must_be_nil
     end
 
-    it 'returns raw attributes' do
+    it "returns raw attributes" do
       _(subject.attributes).must_be_same_as attributes
     end
 
-    it 'returns the subscription expiration date' do
+    it "returns the subscription expiration date" do
       expected = DateTime.new(2016, 6, 9, 13, 59, 40)
       _(subject.expires_date).must_equal expected
     end
 
-    it 'returns the trial status' do
+    it "returns the trial status" do
       _(subject.is_trial_period).must_be_false
     end
   end
 
-  describe 'valid transaction' do
+  describe "valid transaction" do
     before do
-      attributes['cancellation_date'] = '2015-01-12 11:40:46 Etc/GMT'
+      attributes["cancellation_date"] = "2015-01-12 11:40:46 Etc/GMT"
     end
 
-    it 'isn\'t valid' do
+    it "isn't valid" do
       _(subject.valid?).must_be_false
     end
 
-    it 'return nil for cancellation date' do
+    it "return nil for cancellation date" do
       expected = DateTime.new(2015, 1, 12, 11, 40, 46)
       _(subject.cancellation_date).must_equal expected
     end
diff --git a/spec/app_store/subscription_verification_spec.rb b/spec/app_store/subscription_verification_spec.rb
index 0e2b250..a848542 100644
--- a/spec/app_store/subscription_verification_spec.rb
+++ b/spec/app_store/subscription_verification_spec.rb
@@ -1,15 +1,15 @@
-require 'spec_helper'
+require "spec_helper"
 
 describe CandyCheck::AppStore::SubscriptionVerification do
   subject do
     CandyCheck::AppStore::SubscriptionVerification.new(endpoint, data, secret)
   end
-  let(:endpoint) { 'https://some.endpoint' }
-  let(:data)     { 'some_data'   }
-  let(:secret)   { 'some_secret' }
+  let(:endpoint) { "https://some.endpoint" }
+  let(:data)     { "some_data"   }
+  let(:secret)   { "some_secret" }
 
-  it 'returns a verification failure for status != 0' do
-    with_mocked_response('status' => 21_000) do |client, recorded|
+  it "returns a verification failure for status != 0" do
+    with_mocked_response("status" => 21_000) do |client, recorded|
       result = subject.call!
       _(client.receipt_data).must_equal data
       _(client.secret).must_equal secret
@@ -21,7 +21,7 @@
     end
   end
 
-  it 'returns a verification failure when receipt is missing' do
+  it "returns a verification failure when receipt is missing" do
     with_mocked_response({}) do |client, recorded|
       result = subject.call!
       _(client.receipt_data).must_equal data
@@ -34,13 +34,13 @@
     end
   end
 
-  it 'returns a collection of receipt when status is 0 and receipts exists' do
+  it "returns a collection of receipt when status is 0 and receipts exists" do
     response = {
-      'status' => 0,
-      'latest_receipt_info' => [
-        { 'item_id' => 'some_id', 'purchase_date' => '2016-04-15 12:52:40 Etc/GMT' },
-        { 'item_id' => 'some_other_id', 'purchase_date' => '2016-04-15 12:52:40 Etc/GMT' }
-      ]
+      "status" => 0,
+      "latest_receipt_info" => [
+        { "item_id" => "some_id", "purchase_date" => "2016-04-15 12:52:40 Etc/GMT" },
+        { "item_id" => "some_other_id", "purchase_date" => "2016-04-15 12:52:40 Etc/GMT" },
+      ],
     }
     with_mocked_response(response) do
       result = subject.call!
@@ -49,29 +49,30 @@
       _(result.receipts.size).must_equal(2)
       last = result.receipts.last
       _(last).must_be_instance_of CandyCheck::AppStore::Receipt
-      _(last.item_id).must_equal('some_other_id')
+      _(last.item_id).must_equal("some_other_id")
     end
   end
 
-  describe 'filtered product_ids' do
+  describe "filtered product_ids" do
     subject do
       CandyCheck::AppStore::SubscriptionVerification.new(
         endpoint,
         data,
         secret,
-        product_ids
+        product_ids,
       )
     end
-    let(:product_ids) { ['product_1'] }
+    let(:product_ids) { ["product_1"] }
 
-    it 'returns only filtered reciepts when specifc product_ids are reqested' do
+    it "returns only filtered reciepts when specifc product_ids are reqested" do
       response = {
-        'status' => 0,
-        'latest_receipt_info' => [
-          { 'item_id' => 'some_id', 'product_id' => 'product_1', 'purchase_date' => '2016-04-15 12:52:40 Etc/GMT' },
-          { 'item_id' => 'some_other_id', 'product_id' => 'product_1', 'purchase_date' => '2016-04-15 12:52:40 Etc/GMT' },
-          { 'item_id' => 'some_id', 'product_id' => 'product_2', 'purchase_date' => '2016-04-15 12:52:40 Etc/GMT' }
-        ]
+        "status" => 0,
+        "latest_receipt_info" => [
+          { "item_id" => "some_id", "product_id" => "product_1", "purchase_date" => "2016-04-15 12:52:40 Etc/GMT" },
+          { "item_id" => "some_other_id", "product_id" => "product_1",
+            "purchase_date" => "2016-04-15 12:52:40 Etc/GMT" },
+          { "item_id" => "some_id", "product_id" => "product_2", "purchase_date" => "2016-04-15 12:52:40 Etc/GMT" },
+        ],
       }
       with_mocked_response(response) do
         result = subject.call!
@@ -80,26 +81,28 @@
         _(result.receipts.size).must_equal(2)
         last = result.receipts.last
         _(last).must_be_instance_of CandyCheck::AppStore::Receipt
-        _(last.item_id).must_equal('some_other_id')
+        _(last.item_id).must_equal("some_other_id")
       end
     end
   end
 
   private
 
-  DummyClient = Struct.new(:response) do
-    attr_reader :receipt_data, :secret
+  let(:dummy_client_class) do
+    Struct.new(:response) do
+      attr_reader :receipt_data, :secret
 
-    def verify(receipt_data, secret)
-      @receipt_data = receipt_data
-      @secret = secret
-      response
+      def verify(receipt_data, secret)
+        @receipt_data = receipt_data
+        @secret = secret
+        response
+      end
     end
   end
 
   def with_mocked_response(response)
     recorded = []
-    dummy    = DummyClient.new(response)
+    dummy    = dummy_client_class.new(response)
     stub     = proc do |*args|
       recorded << args
       dummy
diff --git a/spec/app_store/verifcation_failure_spec.rb b/spec/app_store/verifcation_failure_spec.rb
index ef17db1..af640df 100644
--- a/spec/app_store/verifcation_failure_spec.rb
+++ b/spec/app_store/verifcation_failure_spec.rb
@@ -1,4 +1,4 @@
-require 'spec_helper'
+require "spec_helper"
 
 describe CandyCheck::AppStore::VerificationFailure do
   subject { CandyCheck::AppStore::VerificationFailure }
@@ -6,23 +6,23 @@
     [21_000, 21_002, 21_003, 21_004, 21_005, 21_006, 21_007, 21_008]
   end
 
-  it 'fetched an failure with message for every known code' do
+  it "fetched an failure with message for every known code" do
     known.each do |code|
       got = subject.fetch(code)
       _(got.code).must_equal code
-      _(got.message).wont_equal 'Unknown error'
+      _(got.message).wont_equal "Unknown error"
     end
   end
 
-  it 'fetched an failure for unknown codes' do
+  it "fetched an failure for unknown codes" do
     got = subject.fetch(1234)
     _(got.code).must_equal 1234
-    _(got.message).must_equal 'Unknown error'
+    _(got.message).must_equal "Unknown error"
   end
 
-  it 'fetched an failure for nil code' do
+  it "fetched an failure for nil code" do
     got = subject.fetch(nil)
     _(got.code).must_equal(-1)
-    _(got.message).must_equal 'Unknown error'
+    _(got.message).must_equal "Unknown error"
   end
 end
diff --git a/spec/app_store/verification_spec.rb b/spec/app_store/verification_spec.rb
index 6fdac6f..58b0f06 100644
--- a/spec/app_store/verification_spec.rb
+++ b/spec/app_store/verification_spec.rb
@@ -1,13 +1,13 @@
-require 'spec_helper'
+require "spec_helper"
 
 describe CandyCheck::AppStore::Verification do
   subject { CandyCheck::AppStore::Verification.new(endpoint, data, secret) }
-  let(:endpoint) { 'https://some.endpoint' }
-  let(:data)     { 'some_data'   }
-  let(:secret)   { 'some_secret' }
+  let(:endpoint) { "https://some.endpoint" }
+  let(:data)     { "some_data"   }
+  let(:secret)   { "some_secret" }
 
-  it 'returns a verification failure for status != 0' do
-    with_mocked_response('status' => 21_000) do |client, recorded|
+  it "returns a verification failure for status != 0" do
+    with_mocked_response("status" => 21_000) do |client, recorded|
       result = subject.call!
       _(client.receipt_data).must_equal data
       _(client.secret).must_equal secret
@@ -19,7 +19,7 @@
     end
   end
 
-  it 'returns a verification failure when receipt is missing' do
+  it "returns a verification failure when receipt is missing" do
     with_mocked_response({}) do |client, recorded|
       result = subject.call!
       _(client.receipt_data).must_equal data
@@ -32,20 +32,32 @@
     end
   end
 
-  it 'returns a receipt when status is 0 and receipt exists' do
-    response = { 'status' => 0, 'receipt' => { 'item_id' => 'some_id' } }
+  it "returns a receipt when status is 0 and receipt exists" do
+    response = { "status" => 0, "receipt" => { "item_id" => "some_id" } }
     with_mocked_response(response) do
       result = subject.call!
       _(result).must_be_instance_of CandyCheck::AppStore::Receipt
-      _(result.item_id).must_equal('some_id')
+      _(result.item_id).must_equal("some_id")
     end
   end
 
   private
 
+  let(:dummy_client_class) do
+    Struct.new(:response) do
+      attr_reader :receipt_data, :secret
+
+      def verify(receipt_data, secret)
+        @receipt_data = receipt_data
+        @secret = secret
+        response
+      end
+    end
+  end
+
   def with_mocked_response(response)
     recorded = []
-    dummy    = DummyClient.new(response)
+    dummy    = dummy_client_class.new(response)
     stub     = proc do |*args|
       recorded << args
       dummy
diff --git a/spec/app_store/verifier_spec.rb b/spec/app_store/verifier_spec.rb
index f96eb10..140fbb1 100644
--- a/spec/app_store/verifier_spec.rb
+++ b/spec/app_store/verifier_spec.rb
@@ -1,4 +1,4 @@
-require 'spec_helper'
+require "spec_helper"
 
 describe CandyCheck::AppStore::Verifier do
   subject { CandyCheck::AppStore::Verifier.new(config) }
@@ -6,32 +6,32 @@
     CandyCheck::AppStore::Config.new(environment: environment)
   end
   let(:environment) { :production }
-  let(:data)     { 'some_data'   }
-  let(:secret)   { 'some_secret' }
+  let(:data)     { "some_data"   }
+  let(:secret)   { "some_secret" }
   let(:receipt)  { CandyCheck::AppStore::Receipt.new({}) }
   let(:receipt_collection) { CandyCheck::AppStore::ReceiptCollection.new({}) }
   let(:production_endpoint) do
-    'https://buy.itunes.apple.com/verifyReceipt'
+    "https://buy.itunes.apple.com/verifyReceipt"
   end
   let(:sandbox_endpoint) do
-    'https://sandbox.itunes.apple.com/verifyReceipt'
+    "https://sandbox.itunes.apple.com/verifyReceipt"
   end
 
-  it 'holds the config' do
+  it "holds the config" do
     _(subject.config).must_be_same_as config
   end
 
-  describe 'sandbox' do
+  describe "sandbox" do
     let(:environment) { :sandbox }
 
-    it 'uses sandbox endpoint without retry on success' do
+    it "uses sandbox endpoint without retry on success" do
       with_mocked_verifier(receipt) do
         _(subject.verify(data, secret)).must_be_same_as receipt
         assert_recorded([sandbox_endpoint, data, secret])
       end
     end
 
-    it 'only uses sandbox endpoint for normal failures' do
+    it "only uses sandbox endpoint for normal failures" do
       failure = get_failure(21_000)
       with_mocked_verifier(failure) do
         _(subject.verify(data, secret)).must_be_same_as failure
@@ -39,29 +39,29 @@
       end
     end
 
-    it 'retries production endpoint for redirect error' do
+    it "retries production endpoint for redirect error" do
       failure = get_failure(21_008)
       with_mocked_verifier(failure, receipt) do
         _(subject.verify(data, secret)).must_be_same_as receipt
         assert_recorded(
           [sandbox_endpoint, data, secret],
-          [production_endpoint, data, secret]
+          [production_endpoint, data, secret],
         )
       end
     end
   end
 
-  describe 'production' do
+  describe "production" do
     let(:environment) { :production }
 
-    it 'uses production endpoint without retry on success' do
+    it "uses production endpoint without retry on success" do
       with_mocked_verifier(receipt) do
         _(subject.verify(data, secret)).must_be_same_as receipt
         assert_recorded([production_endpoint, data, secret])
       end
     end
 
-    it 'only uses production endpoint for normal failures' do
+    it "only uses production endpoint for normal failures" do
       failure = get_failure(21_000)
       with_mocked_verifier(failure) do
         _(subject.verify(data, secret)).must_be_same_as failure
@@ -69,31 +69,31 @@
       end
     end
 
-    it 'retries production endpoint for redirect error' do
+    it "retries production endpoint for redirect error" do
       failure = get_failure(21_007)
       with_mocked_verifier(failure, receipt) do
         _(subject.verify(data, secret)).must_be_same_as receipt
         assert_recorded(
           [production_endpoint, data, secret],
-          [sandbox_endpoint, data, secret]
+          [sandbox_endpoint, data, secret],
         )
       end
     end
   end
 
-  describe 'subscription' do
+  describe "subscription" do
     let(:environment) { :production }
 
-    it 'uses production endpoint without retry on success' do
+    it "uses production endpoint without retry on success" do
       with_mocked_verifier(receipt_collection) do
         _(subject.verify_subscription(
-          data, secret
-        )).must_be_same_as receipt_collection
+            data, secret
+          )).must_be_same_as receipt_collection
         assert_recorded([production_endpoint, data, secret, nil])
       end
     end
 
-    it 'only uses production endpoint for normal failures' do
+    it "only uses production endpoint for normal failures" do
       failure = get_failure(21_000)
       with_mocked_verifier(failure) do
         _(subject.verify_subscription(data, secret)).must_be_same_as failure
@@ -101,23 +101,23 @@
       end
     end
 
-    it 'retries production endpoint for redirect error' do
+    it "retries production endpoint for redirect error" do
       failure = get_failure(21_007)
       with_mocked_verifier(failure, receipt) do
         _(subject.verify_subscription(data, secret)).must_be_same_as receipt
         assert_recorded(
           [production_endpoint, data, secret, nil],
-          [sandbox_endpoint, data, secret, nil]
+          [sandbox_endpoint, data, secret, nil],
         )
       end
     end
 
-    it 'passed the product_ids' do
-      product_ids = ['product_1']
+    it "passed the product_ids" do
+      product_ids = ["product_1"]
       with_mocked_verifier(receipt_collection) do
         _(subject.verify_subscription(
-          data, secret, product_ids
-        )).must_be_same_as receipt_collection
+            data, secret, product_ids
+          )).must_be_same_as receipt_collection
         assert_recorded([production_endpoint, data, secret, product_ids])
       end
     end
@@ -125,15 +125,23 @@
 
   private
 
-  def with_mocked_verifier(*results)
+  let(:dummy_verification_class) do
+    Struct.new(:endpoint, :data, :secret, :product_ids) do
+      attr_accessor :results
+
+      def call!
+        results.shift
+      end
+    end
+  end
+
+  def with_mocked_verifier(*results, &block)
     @recorded ||= []
     stub = proc do |*args|
       @recorded << args
-      DummyAppStoreVerification.new(*args).tap { |v| v.results = results }
-    end
-    CandyCheck::AppStore::Verification.stub :new, stub do
-      yield
+      dummy_verification_class.new(*args).tap { |v| v.results = results }
     end
+    CandyCheck::AppStore::Verification.stub :new, stub, &block
   end
 
   def assert_recorded(*calls)
@@ -143,20 +151,4 @@ def assert_recorded(*calls)
   def get_failure(code)
     CandyCheck::AppStore::VerificationFailure.fetch(code)
   end
-
-  class DummyAppStoreVerification
-    attr_reader :endpoint, :data, :secret, :product_ids
-    attr_accessor :results
-
-    def initialize(endpoint, data, secret, product_ids = nil)
-      @endpoint = endpoint
-      @data = data
-      @secret = secret
-      @product_ids = product_ids
-    end
-
-    def call!
-      results.shift
-    end
-  end
 end
diff --git a/spec/cli/app_spec.rb b/spec/cli/app_spec.rb
index 513d9b8..23718be 100644
--- a/spec/cli/app_spec.rb
+++ b/spec/cli/app_spec.rb
@@ -1,42 +1,40 @@
-require 'spec_helper'
+require "spec_helper"
 
 describe CandyCheck::CLI::App do
   subject { CandyCheck::CLI::App.new }
 
-  it 'supports the version command' do
+  it "supports the version command" do
     stub_command(CandyCheck::CLI::Commands::Version) do
       _(subject.version).must_equal :stubbed
       _(@arguments).must_be_empty
     end
   end
 
-  it 'supports the app_store command' do
+  it "supports the app_store command" do
     stub_command(CandyCheck::CLI::Commands::AppStore) do
-      _(subject.app_store('receipt')).must_equal :stubbed
-      _(@arguments).must_equal ['receipt']
+      _(subject.app_store("receipt")).must_equal :stubbed
+      _(@arguments).must_equal ["receipt"]
     end
   end
 
-  it 'supports the play_store command' do
+  it "supports the play_store command" do
     stub_command(CandyCheck::CLI::Commands::PlayStore) do
-      _(subject.play_store('package', 'id', 'token')).must_equal :stubbed
-      _(@arguments).must_equal ['package', 'id', 'token']
+      _(subject.play_store("package", "id", "token")).must_equal :stubbed
+      _(@arguments).must_equal %w(package id token)
     end
   end
 
-  it 'returns true when call .exit_on_failure?' do
+  it "returns true when call .exit_on_failure?" do
     _(CandyCheck::CLI::App.exit_on_failure?).must_equal true
   end
 
   private
 
-  def stub_command(target)
+  def stub_command(target, &block)
     stub = proc do |*args|
       @arguments = args
       :stubbed
     end
-    target.stub :run, stub do
-      yield
-    end
+    target.stub :run, stub, &block
   end
 end
diff --git a/spec/cli/commands/app_store_spec.rb b/spec/cli/commands/app_store_spec.rb
index 24bd774..857c494 100644
--- a/spec/cli/commands/app_store_spec.rb
+++ b/spec/cli/commands/app_store_spec.rb
@@ -1,56 +1,55 @@
-require 'spec_helper'
+require "spec_helper"
 
 describe CandyCheck::CLI::Commands::AppStore do
   include WithCommand
   subject { CandyCheck::CLI::Commands::AppStore }
   let(:arguments) { [receipt, options] }
-  let(:receipt) { 'data' }
+  let(:receipt) { "data" }
   let(:options) do
     {
-      environment: :sandbox
+      environment: :sandbox,
     }
   end
+  let(:dummy_verifier_class) do
+    Struct.new(:config) do
+      attr_reader :arguments
+
+      def verify(*arguments)
+        @arguments = arguments
+        { result: :stubbed }
+      end
+    end
+  end
 
   before do
     stub = proc do |*args|
-      @verifier = DummyAppStoreVerifier.new(*args)
+      @verifier = dummy_verifier_class.new(*args)
     end
     CandyCheck::AppStore::Verifier.stub :new, stub do
       run_command!
     end
   end
 
-  describe 'default' do
-    it 'uses the receipt and the options' do
+  describe "default" do
+    it "uses the receipt and the options" do
       _(@verifier.config.environment).must_equal :sandbox
       _(@verifier.arguments).must_equal [receipt, nil]
-      _(out.lines).must_equal ['Hash:', { result: :stubbed }]
+      _(out.lines).must_equal ["Hash:", { result: :stubbed }]
     end
   end
 
-  describe 'with secret' do
+  describe "with secret" do
     let(:options) do
       {
         environment: :production,
-        secret: 'notasecret'
+        secret: "notasecret",
       }
     end
 
-    it 'uses the secret for verification' do
+    it "uses the secret for verification" do
       _(@verifier.config.environment).must_equal :production
-      _(@verifier.arguments).must_equal [receipt, 'notasecret']
-      _(out.lines).must_equal ['Hash:', { result: :stubbed }]
-    end
-  end
-
-  private
-
-  DummyAppStoreVerifier = Struct.new(:config) do
-    attr_reader :arguments
-
-    def verify(*arguments)
-      @arguments = arguments
-      { result: :stubbed }
+      _(@verifier.arguments).must_equal [receipt, "notasecret"]
+      _(out.lines).must_equal ["Hash:", { result: :stubbed }]
     end
   end
 end
diff --git a/spec/cli/commands/play_store_spec.rb b/spec/cli/commands/play_store_spec.rb
index 5a7013a..05da8cd 100644
--- a/spec/cli/commands/play_store_spec.rb
+++ b/spec/cli/commands/play_store_spec.rb
@@ -2,7 +2,9 @@
 
 describe CandyCheck::CLI::Commands::PlayStore do
   include WithCommand
-  subject { CandyCheck::CLI::Commands::PlayStore.new(package_name, product_id, token, "json_key_file" => json_key_file) }
+  subject do
+    CandyCheck::CLI::Commands::PlayStore.new(package_name, product_id, token, "json_key_file" => json_key_file)
+  end
   let(:package_name) { "my_package_name" }
   let(:product_id) { "my_product_id" }
   let(:token) { "my_token" }
diff --git a/spec/cli/commands/version_spec.rb b/spec/cli/commands/version_spec.rb
index 10760b0..26e5cd1 100644
--- a/spec/cli/commands/version_spec.rb
+++ b/spec/cli/commands/version_spec.rb
@@ -1,10 +1,10 @@
-require 'spec_helper'
+require "spec_helper"
 
 describe CandyCheck::CLI::Commands::Version do
   include WithCommand
   subject { CandyCheck::CLI::Commands::Version }
 
-  it 'prints the gem\'s version' do
+  it "prints the gem's version" do
     run_command!
     _(out.lines).must_equal [CandyCheck::VERSION]
   end
diff --git a/spec/cli/out_spec.rb b/spec/cli/out_spec.rb
index 7a3a160..a04bbc2 100644
--- a/spec/cli/out_spec.rb
+++ b/spec/cli/out_spec.rb
@@ -1,34 +1,34 @@
-require 'spec_helper'
+require "spec_helper"
 
 describe CandyCheck::CLI::Out do
   subject { CandyCheck::CLI::Out.new(out) }
   let(:out) { StringIO.new }
 
-  it 'defaults to use STDOUT' do
+  it "defaults to use STDOUT" do
     _(CandyCheck::CLI::Out.new.out).must_be_same_as $stdout
   end
 
-  it 'holds the outlet' do
+  it "holds the outlet" do
     _(subject.out).must_be_same_as out
   end
 
-  it 'prints to outlet' do
-    subject.print 'some text'
-    subject.print 'another line'
+  it "prints to outlet" do
+    subject.print "some text"
+    subject.print "another line"
     close
     _(out.readlines).must_equal [
       "some text\n",
-      "another line\n"
+      "another line\n",
     ]
   end
 
-  it 'pretty prints to outlet' do
+  it "pretty prints to outlet" do
     subject.pretty dummy: 1
     subject.pretty [1, 2, 3]
     close
     _(out.readlines).must_equal [
       "{:dummy=>1}\n",
-      "[1, 2, 3]\n"
+      "[1, 2, 3]\n",
     ]
   end
 
diff --git a/spec/play_store/acknowledger_spec.rb b/spec/play_store/acknowledger_spec.rb
index 0fbb1e2..1f1247d 100644
--- a/spec/play_store/acknowledger_spec.rb
+++ b/spec/play_store/acknowledger_spec.rb
@@ -21,7 +21,9 @@
       end
     end
     it "when already acknowledged" do
+      # rubocop:disable Layout/LineLength
       error_body = "{\n  \"error\": {\n    \"code\": 400,\n    \"message\": \"The purchase is not in a valid state to perform the desired operation.\",\n    \"errors\": [\n      {\n        \"message\": \"The purchase is not in a valid state to perform the desired operation.\",\n        \"domain\": \"androidpublisher\",\n        \"reason\": \"invalidPurchaseState\",\n        \"location\": \"token\",\n        \"locationType\": \"parameter\"\n      }\n    ]\n  }\n}\n"
+      # rubocop:enable Layout/LineLength
 
       VCR.use_cassette("play_store/product_acknowledgements/already_acknowledged") do
         result = subject.acknowledge_product_purchase(package_name: package_name, product_id: product_id, token: token)
@@ -33,7 +35,9 @@
       end
     end
     it "when it has been refunded" do
+      # rubocop:disable Layout/LineLength
       error_body = "{\n  \"error\": {\n    \"code\": 400,\n    \"message\": \"The product purchase is not owned by the user.\",\n    \"errors\": [\n      {\n        \"message\": \"The product purchase is not owned by the user.\",\n        \"domain\": \"androidpublisher\",\n        \"reason\": \"productNotOwnedByUser\"\n      }\n    ]\n  }\n}\n"
+      # rubocop:enable Layout/LineLength
 
       VCR.use_cassette("play_store/product_acknowledgements/refunded") do
         result = subject.acknowledge_product_purchase(package_name: package_name, product_id: product_id, token: token)
diff --git a/spec/play_store/product_acknowledgements/acknowledgement_spec.rb b/spec/play_store/product_acknowledgements/acknowledgement_spec.rb
index b7c1d86..c5b15b2 100644
--- a/spec/play_store/product_acknowledgements/acknowledgement_spec.rb
+++ b/spec/play_store/product_acknowledgements/acknowledgement_spec.rb
@@ -27,7 +27,9 @@
       end
     end
     it "when already acknowledged" do
+      # rubocop:disable Layout/LineLength
       error_body = "{\n  \"error\": {\n    \"code\": 400,\n    \"message\": \"The purchase is not in a valid state to perform the desired operation.\",\n    \"errors\": [\n      {\n        \"message\": \"The purchase is not in a valid state to perform the desired operation.\",\n        \"domain\": \"androidpublisher\",\n        \"reason\": \"invalidPurchaseState\",\n        \"location\": \"token\",\n        \"locationType\": \"parameter\"\n      }\n    ]\n  }\n}\n"
+      # rubocop:enable Layout/LineLength
 
       VCR.use_cassette("play_store/product_acknowledgements/already_acknowledged") do
         result = subject.call!
@@ -39,7 +41,9 @@
       end
     end
     it "when it has been refunded" do
+      # rubocop:disable Layout/LineLength
       error_body = "{\n  \"error\": {\n    \"code\": 400,\n    \"message\": \"The product purchase is not owned by the user.\",\n    \"errors\": [\n      {\n        \"message\": \"The product purchase is not owned by the user.\",\n        \"domain\": \"androidpublisher\",\n        \"reason\": \"productNotOwnedByUser\"\n      }\n    ]\n  }\n}\n"
+      # rubocop:enable Layout/LineLength
 
       VCR.use_cassette("play_store/product_acknowledgements/refunded") do
         result = subject.call!
diff --git a/spec/play_store/product_acknowledgements/response_spec.rb b/spec/play_store/product_acknowledgements/response_spec.rb
index 99e05f2..e029a68 100644
--- a/spec/play_store/product_acknowledgements/response_spec.rb
+++ b/spec/play_store/product_acknowledgements/response_spec.rb
@@ -5,23 +5,23 @@
     CandyCheck::PlayStore::ProductAcknowledgements::Response.new(result: result, error_data: error_data)
   end
 
-  describe '#acknowledged?' do
-    context 'when result present' do
-      let(:result) { '' }
+  describe "#acknowledged?" do
+    context "when result present" do
+      let(:result) { "" }
       let(:error_data)  { nil }
 
-      it 'returns true' do
+      it "returns true" do
         result = subject.acknowledged?
 
         _(result).must_be_true
       end
     end
 
-    context 'when result is not present' do
+    context "when result is not present" do
       let(:result) { nil }
-      let(:error_data)  { nil }
+      let(:error_data) { nil }
 
-      it 'returns false' do
+      it "returns false" do
         result = subject.acknowledged?
 
         _(result).must_be_false
@@ -29,34 +29,35 @@
     end
   end
 
-  describe '#error' do
-    context 'when error present' do
+  describe "#error" do
+    context "when error present" do
       let(:result) { nil }
       let(:error_data) do
         Module.new do
           def status_code
             400
           end
+
           def body
-            'A String describing the issue'
+            "A String describing the issue"
           end
           module_function :status_code, :body
         end
       end
 
-      it 'returns the expected data' do
+      it "returns the expected data" do
         result = subject.error
 
         _(result[:status_code]).must_equal(400)
-        _(result[:body]).must_equal('A String describing the issue')
+        _(result[:body]).must_equal("A String describing the issue")
       end
     end
 
-    context 'when error is not present' do
-      let(:result) { '' }
+    context "when error is not present" do
+      let(:result) { "" }
       let(:error_data)  { nil }
 
-      it 'returns false' do
+      it "returns false" do
         result = subject.error
 
         _(result).must_be_nil
diff --git a/spec/play_store/product_purchases/product_purchase_spec.rb b/spec/play_store/product_purchases/product_purchase_spec.rb
index 2416dc1..092a2c6 100644
--- a/spec/play_store/product_purchases/product_purchase_spec.rb
+++ b/spec/play_store/product_purchases/product_purchase_spec.rb
@@ -5,13 +5,13 @@
 
   describe "valid and non-consumed product" do
     let(:fake_product_purchase) do
-      FakeProductPurchase.new(
+      OpenStruct.new(
         consumption_state: 0,
         developer_payload: "payload that gets stored and returned",
         kind: "androidpublisher#productPurchase",
         order_id: "ABC123",
         purchase_state: 0,
-        purchase_time_millis: 1421676237413,
+        purchase_time_millis: 1_421_676_237_413,
       )
     end
 
@@ -51,13 +51,13 @@
 
   describe "valid and consumed product" do
     let(:fake_product_purchase) do
-      FakeProductPurchase.new(
+      OpenStruct.new(
         consumption_state: 1,
         developer_payload: "payload that gets stored and returned",
         kind: "androidpublisher#productPurchase",
         order_id: "ABC123",
         purchase_state: 0,
-        purchase_time_millis: 1421676237413,
+        purchase_time_millis: 1_421_676_237_413,
       )
     end
 
@@ -72,13 +72,13 @@
 
   describe "non-valid product" do
     let(:fake_product_purchase) do
-      FakeProductPurchase.new(
+      OpenStruct.new(
         consumption_state: 0,
         developer_payload: "payload that gets stored and returned",
         kind: "androidpublisher#productPurchase",
         order_id: "ABC123",
         purchase_state: 1,
-        purchase_time_millis: 1421676237413,
+        purchase_time_millis: 1_421_676_237_413,
       )
     end
 
@@ -86,25 +86,4 @@
       _(subject.valid?).must_be_false
     end
   end
-
-  private
-
-  class FakeProductPurchase
-    FIELDS = [
-      :consumption_state,
-      :developer_payload,
-      :kind,
-      :order_id,
-      :purchase_state,
-      :purchase_time_millis,
-    ].freeze
-
-    attr_accessor(*FIELDS)
-
-    def initialize(hash)
-      FIELDS.each do |key|
-        self.public_send("#{key}=", hash[key])
-      end
-    end
-  end
 end
diff --git a/spec/play_store/subscription_purchases/subscription_purchase_spec.rb b/spec/play_store/subscription_purchases/subscription_purchase_spec.rb
index 3880a49..6e8a8ac 100644
--- a/spec/play_store/subscription_purchases/subscription_purchase_spec.rb
+++ b/spec/play_store/subscription_purchases/subscription_purchase_spec.rb
@@ -5,10 +5,10 @@
 
   describe "expired and canceled subscription" do
     let(:fake_subscription_purchase) do
-      FakeSubscriptionPurchase.new(
+      OpenStruct.new(
         kind: "androidpublisher#subscriptionPurchase",
-        start_time_millis: 1459540113244,
-        expiry_time_millis: 1462132088610,
+        start_time_millis: 1_459_540_113_244,
+        expiry_time_millis: 1_462_132_088_610,
         auto_renewing: false,
         developer_payload: "payload that gets stored and returned",
         cancel_reason: 0,
@@ -66,10 +66,11 @@
 
   describe "unexpired and renewing subscription" do
     two_days_from_now = DateTime.now + 2
+
     let(:fake_subscription_purchase) do
-      FakeSubscriptionPurchase.new(
+      OpenStruct.new(
         kind: "androidpublisher#subscriptionPurchase",
-        start_time_millis: 1459540113244,
+        start_time_millis: 1_459_540_113_244,
         expiry_time_millis: (two_days_from_now.to_time.to_i * 1000),
         auto_renewing: true,
         developer_payload: "payload that gets stored and returned",
@@ -89,10 +90,10 @@
 
   describe "expired due to payment failure" do
     let(:fake_subscription_purchase) do
-      FakeSubscriptionPurchase.new(
+      OpenStruct.new(
         kind: "androidpublisher#subscriptionPurchase",
-        start_time_millis: 1459540113244,
-        expiry_time_millis: 1462132088610,
+        start_time_millis: 1_459_540_113_244,
+        expiry_time_millis: 1_462_132_088_610,
         auto_renewing: true,
         developer_payload: "payload that gets stored and returned",
         cancel_reason: 1,
@@ -112,10 +113,10 @@
   describe "subscription cancelation by user" do
     describe "when subscription is not canceled" do
       let(:fake_subscription_purchase) do
-        FakeSubscriptionPurchase.new(
+        OpenStruct.new(
           kind: "androidpublisher#subscriptionPurchase",
-          start_time_millis: 1459540113244,
-          expiry_time_millis: 1462132088610,
+          start_time_millis: 1_459_540_113_244,
+          expiry_time_millis: 1_462_132_088_610,
           auto_renewing: true,
           developer_payload: "payload that gets stored and returned",
           payment_state: 1,
@@ -137,11 +138,11 @@
 
     describe "when subscription is canceled" do
       let(:fake_subscription_purchase) do
-        FakeSubscriptionPurchase.new(
+        OpenStruct.new(
           kind: "androidpublisher#subscriptionPurchase",
-          start_time_millis: 1459540113244,
-          expiry_time_millis: 1462132088610,
-          user_cancellation_time_millis: 1461872888000,
+          start_time_millis: 1_459_540_113_244,
+          expiry_time_millis: 1_462_132_088_610,
+          user_cancellation_time_millis: 1_461_872_888_000,
           auto_renewing: true,
           developer_payload: "payload that gets stored and returned",
           cancel_reason: 0,
@@ -166,10 +167,10 @@
 
   describe "expired with pending payment" do
     let(:fake_subscription_purchase) do
-      FakeSubscriptionPurchase.new(
+      OpenStruct.new(
         kind: "androidpublisher#subscriptionPurchase",
-        start_time_millis: 1459540113244,
-        expiry_time_millis: 1462132088610,
+        start_time_millis: 1_459_540_113_244,
+        expiry_time_millis: 1_462_132_088_610,
         auto_renewing: true,
         developer_payload: "payload that gets stored and returned",
         cancel_reason: 0,
@@ -188,10 +189,10 @@
 
   describe "trial" do
     let(:fake_subscription_purchase) do
-      FakeSubscriptionPurchase.new(
+      OpenStruct.new(
         kind: "androidpublisher#subscriptionPurchase",
-        start_time_millis: 1459540113244,
-        expiry_time_millis: 1462132088610,
+        start_time_millis: 1_459_540_113_244,
+        expiry_time_millis: 1_462_132_088_610,
         auto_renewing: false,
         developer_payload: "payload that gets stored and returned",
         cancel_reason: 0,
@@ -209,29 +210,4 @@
       _(subject.price_currency_code).must_equal "SOMECODE"
     end
   end
-
-  private
-
-  class FakeSubscriptionPurchase
-    FIELDS = [
-      :kind,
-      :start_time_millis,
-      :expiry_time_millis,
-      :user_cancellation_time_millis,
-      :auto_renewing,
-      :developer_payload,
-      :cancel_reason,
-      :payment_state,
-      :price_amount_micros,
-      :price_currency_code,
-    ].freeze
-
-    attr_accessor(*FIELDS)
-
-    def initialize(hash)
-      FIELDS.each do |key|
-        self.public_send("#{key}=", hash[key])
-      end
-    end
-  end
 end
diff --git a/spec/play_store/verification_failure_spec.rb b/spec/play_store/verification_failure_spec.rb
index fa31f5f..ec579a3 100644
--- a/spec/play_store/verification_failure_spec.rb
+++ b/spec/play_store/verification_failure_spec.rb
@@ -3,9 +3,13 @@
 describe CandyCheck::PlayStore::VerificationFailure do
   subject { CandyCheck::PlayStore::VerificationFailure.new(fake_error) }
 
+  let(:fake_error_class) do
+    Struct.new(:status_code, :message)
+  end
+
   describe "denied" do
     let(:fake_error) do
-      FakeError.new("401", "The current user has insufficient permissions")
+      fake_error_class.new("401", "The current user has insufficient permissions")
     end
 
     it "returns the code" do
@@ -19,7 +23,7 @@
 
   describe "empty" do
     let(:fake_error) do
-      FakeError.new(nil, nil)
+      fake_error_class.new(nil, nil)
     end
 
     it "returns an unknown code" do
@@ -30,6 +34,4 @@
       _(subject.message).must_equal "Unknown error"
     end
   end
-
-  FakeError = Struct.new(:status_code, :message)
 end
diff --git a/spec/play_store/verifier_spec.rb b/spec/play_store/verifier_spec.rb
index 74e9cc8..9c5863e 100644
--- a/spec/play_store/verifier_spec.rb
+++ b/spec/play_store/verifier_spec.rb
@@ -32,14 +32,16 @@
   describe "subscription purchases" do
     it "verifies a subscription purchase" do
       VCR.use_cassette("play_store/subscription_purchases/valid_but_expired") do
-        result = subject.verify_subscription_purchase(package_name: package_name, subscription_id: subscription_id, token: token)
+        result = subject.verify_subscription_purchase(package_name: package_name, subscription_id: subscription_id,
+                                                      token: token)
         _(result).must_be_instance_of CandyCheck::PlayStore::SubscriptionPurchases::SubscriptionPurchase
       end
     end
 
     it "can return a subscription purchase verification failure" do
       VCR.use_cassette("play_store/subscription_purchases/permission_denied") do
-        result = subject.verify_subscription_purchase(package_name: package_name, subscription_id: subscription_id, token: token)
+        result = subject.verify_subscription_purchase(package_name: package_name, subscription_id: subscription_id,
+                                                      token: token)
         _(result).must_be_instance_of CandyCheck::PlayStore::VerificationFailure
       end
     end
diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index 70b6004..8b10098 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -1,4 +1,3 @@
-
 require "candy_check"
 require "candy_check/cli"
 
@@ -38,14 +37,13 @@ def in_continuous_integration_environment?
 
 ENV["DEBUG"] && Google::APIClient.logger.level = Logger::DEBUG
 
-class MiniTest::Spec
-  class << self
-    alias :context :describe
+module MiniTest
+  class Spec
+    class << self
+      alias context describe
+    end
   end
-end
-
 
-module MiniTest
   module Assertions
     # The first parameter must be ```true```, not coercible to true.
     def assert_true(obj, msg = nil)