diff --git a/app/models/oms/billing_address.rb b/app/models/oms/billing_address.rb
new file mode 100644
index 0000000..c66e880
--- /dev/null
+++ b/app/models/oms/billing_address.rb
@@ -0,0 +1,9 @@
+require "flex_commerce_api/oms/api_base"
+
+module FlexCommerce
+  module OMS
+    class BillingAddress < FlexCommerceApi::OMS::ApiBase
+      belongs_to :customer_order, class_name: "::FlexCommerce::OMS::CustomerOrder"
+    end
+  end
+end
diff --git a/app/models/oms/customer.rb b/app/models/oms/customer.rb
new file mode 100644
index 0000000..49ee4dc
--- /dev/null
+++ b/app/models/oms/customer.rb
@@ -0,0 +1,9 @@
+require "flex_commerce_api/oms/api_base"
+
+module FlexCommerce
+  module OMS
+    class Customer < FlexCommerceApi::OMS::ApiBase
+      belongs_to :customer_order, class_name: "::FlexCommerce::OMS::CustomerOrder"
+    end
+  end
+end
diff --git a/app/models/oms/customer_order.rb b/app/models/oms/customer_order.rb
new file mode 100644
index 0000000..d8c7096
--- /dev/null
+++ b/app/models/oms/customer_order.rb
@@ -0,0 +1,15 @@
+require "flex_commerce_api/oms/api_base"
+require "flex_commerce_api/api_base"
+module FlexCommerce
+  module OMS
+    class CustomerOrder < FlexCommerceApi::OMS::ApiBase
+      has_many :payments, class_name: "::FlexCommerce::OMS::Payments"
+      has_many :line_items, class_name: "::FlexCommerce::OMS::LineItem"
+      has_many :discounts, class_name: "::FlexCommerce::OMS::Discount"
+      has_many :shipping_address, class_name: "::FlexCommerce::OMS::Address"
+      has_one :billing_address, class_name: "::FlexCommerce::OMS::Address"
+      has_one :customer, class_name: "::FlexCommerce::OMS::Customer"
+      has_one :shipping_method, class_name: "::FlexCommerce::OMS::ShippingMethod"
+    end
+  end
+end
diff --git a/app/models/oms/discount.rb b/app/models/oms/discount.rb
new file mode 100644
index 0000000..9591254
--- /dev/null
+++ b/app/models/oms/discount.rb
@@ -0,0 +1,9 @@
+require "flex_commerce_api/oms/api_base"
+
+module FlexCommerce
+  module OMS
+    class Discount < FlexCommerceApi::OMS::ApiBase
+      belongs_to :customer_order, class_name: "::FlexCommerce::OMS::CustomerOrder"
+    end
+  end
+end
diff --git a/app/models/oms/line_item.rb b/app/models/oms/line_item.rb
new file mode 100644
index 0000000..e3dfe7c
--- /dev/null
+++ b/app/models/oms/line_item.rb
@@ -0,0 +1,9 @@
+require "flex_commerce_api/oms/api_base"
+
+module FlexCommerce
+  module OMS
+    class LineItem < FlexCommerceApi::OMS::ApiBase
+      belongs_to :customer_order, class_name: "::FlexCommerce::OMS::CustomerOrder"
+    end
+  end
+end
diff --git a/app/models/oms/payment.rb b/app/models/oms/payment.rb
new file mode 100644
index 0000000..a97a7d9
--- /dev/null
+++ b/app/models/oms/payment.rb
@@ -0,0 +1,9 @@
+require "flex_commerce_api/oms/api_base"
+
+module FlexCommerce
+  module OMS
+    class Payment < FlexCommerceApi::OMS::ApiBase
+      belongs_to :customer_order, class_name: "::FlexCommerce::OMS::CustomerOrder"
+    end
+  end
+end
diff --git a/app/models/oms/shipping_address.rb b/app/models/oms/shipping_address.rb
new file mode 100644
index 0000000..f842598
--- /dev/null
+++ b/app/models/oms/shipping_address.rb
@@ -0,0 +1,9 @@
+require "flex_commerce_api/oms/api_base"
+
+module FlexCommerce
+  module OMS
+    class ShippingAddress < FlexCommerceApi::OMS::ApiBase
+      belongs_to :customer_order, class_name: "::FlexCommerce::OMS::CustomerOrder"
+    end
+  end
+end
diff --git a/app/models/oms/shipping_method.rb b/app/models/oms/shipping_method.rb
new file mode 100644
index 0000000..c52383b
--- /dev/null
+++ b/app/models/oms/shipping_method.rb
@@ -0,0 +1,9 @@
+require "flex_commerce_api/oms/api_base"
+
+module FlexCommerce
+  module OMS
+    class ShippingMethod < FlexCommerceApi::OMS::ApiBase
+      belongs_to :customer_order, class_name: "::FlexCommerce::OMS::CustomerOrder"
+    end
+  end
+end
diff --git a/lib/flex_commerce.rb b/lib/flex_commerce.rb
index 394ebea..a01dad5 100644
--- a/lib/flex_commerce.rb
+++ b/lib/flex_commerce.rb
@@ -12,6 +12,18 @@ module V2
     autoload :UnallocateOrder, File.join(FlexCommerce.gem_root, "app", "models", "v2", "unallocate_order")
   end
 
+  # OMS
+  module OMS
+    autoload :BillingAddress, File.join(FlexCommerce.gem_root, "app", "models", "oms", "billing_address")
+    autoload :CustomerOrder, File.join(FlexCommerce.gem_root, "app", "models", "oms", "customer_order")
+    autoload :Customer, File.join(FlexCommerce.gem_root, "app", "models", "oms", "customer")
+    autoload :Discount, File.join(FlexCommerce.gem_root, "app", "models", "oms", "discount")
+    autoload :LineItem, File.join(FlexCommerce.gem_root, "app", "models", "oms", "line_item")
+    autoload :Payment, File.join(FlexCommerce.gem_root, "app", "models", "oms", "payment")
+    autoload :ShippingAddress, File.join(FlexCommerce.gem_root, "app", "models", "oms", "shipping_address")
+    autoload :ShippingMethod, File.join(FlexCommerce.gem_root, "app", "models", "oms", "shipping_method")
+  end
+
   # V1 Models
   autoload :Address, File.join(gem_root, "app", "models", "address")
   autoload :AssetFile, File.join(gem_root, "app", "models", "asset_file")
diff --git a/lib/flex_commerce_api/oms/api_base.rb b/lib/flex_commerce_api/oms/api_base.rb
new file mode 100644
index 0000000..54ade02
--- /dev/null
+++ b/lib/flex_commerce_api/oms/api_base.rb
@@ -0,0 +1,13 @@
+require "flex_commerce_api/base_resource"
+
+module FlexCommerceApi
+  module OMS
+    class ApiBase < FlexCommerceApi::BaseResource
+      def self.endpoint_version
+        "v1/oms"
+      end
+
+      reconfigure
+    end
+  end
+end
diff --git a/lib/flex_commerce_api/version.rb b/lib/flex_commerce_api/version.rb
index aaf7496..4aeddfd 100644
--- a/lib/flex_commerce_api/version.rb
+++ b/lib/flex_commerce_api/version.rb
@@ -1,3 +1,3 @@
 module FlexCommerceApi
-  VERSION = "0.8.3"
+  VERSION = "0.8.4"
 end
diff --git a/lib/patches/json_api_client/resource.rb b/lib/patches/json_api_client/resource.rb
new file mode 100644
index 0000000..b98a963
--- /dev/null
+++ b/lib/patches/json_api_client/resource.rb
@@ -0,0 +1,43 @@
+require "json_api_client/version"
+if ["1.5.3"].include?(JsonApiClient::VERSION)
+  require "json_api_client/resource"
+  module JsonApiClient
+    class Resource
+      def save
+        return false unless valid?
+
+        self.last_result_set = if persisted?
+          self.class.requestor.update(self)
+        else
+          self.class.requestor.create(self)
+        end
+
+        if last_result_set.has_errors?
+          fill_errors
+          false
+        else
+          self.errors.clear if self.errors
+          mark_as_persisted!
+          if updated = last_result_set.first
+            self.attributes = updated.attributes
+            # This line has been added as part of https://github.com/chingor13/json_api_client/pull/238
+            self.links.attributes = updated.links.attributes
+            self.relationships.attributes = updated.relationships.attributes
+            clear_changes_information
+            # This line has been added as part of https://github.com/JsonApiClient/json_api_client/pull/285
+            self.relationships.clear_changes_information
+          end
+          true
+        end
+      end
+    end
+  end
+else
+  raise %q(
+    Please check these two PRs:
+      * https://github.com/chingor13/json_api_client/pull/238 (This was released in version 1.5.0)
+      * https://github.com/JsonApiClient/json_api_client/pull/285 (This hasn't yet been released at the time of writing this)
+    If both have been merged into the gem version you are using, remove this file (#{__FILE__}).
+    If not, add the current version to the allowed array at the top of this file.
+  )
+end
diff --git a/lib/paypal_express/auth.rb b/lib/paypal_express/auth.rb
index 9786745..6005edf 100644
--- a/lib/paypal_express/auth.rb
+++ b/lib/paypal_express/auth.rb
@@ -6,14 +6,14 @@
 module FlexCommerce
   module PaypalExpress
     # @class Setup
-    #  
+    #
     # This service authorises the payment via the Paypal gateway
     class Auth
       include ::Retry
       include ::FlexCommerce::PaypalExpress::Api
-      
+
       DEFAULT_CURRENCY = "GBP"
-      
+
       # @initialize
       #
       # @param {String} token - Paypal token
@@ -29,9 +29,9 @@ def initialize(cart:, token:, payer_id:, payment_transaction:, gateway_class: ::
       def call
         process_with_gateway
       end
- 
+
       private
-  
+
       attr_accessor :cart, :token, :payer_id, :payment_transaction, :gateway_class
 
       def process_with_gateway
@@ -63,7 +63,7 @@ def process_with_gateway
       def do_express_checkout_payment
         Retry.call(no_of_retries: no_of_retires, rescue_errors: ::ActiveMerchant::ConnectionError) {
           ::NewRelic::Agent.increment_metric('Custom/Paypal/Do_Express_Checkout_Payment') if defined?(NewRelic::Agent)
-          gateway.order(convert_amount(cart.total), token: token, payer_id: payer_id, currency: DEFAULT_CURRENCY)
+          gateway.order(convert_amount(payment_transaction.amount), token: token, payer_id: payer_id, currency: DEFAULT_CURRENCY)
         }
       end
 
@@ -71,7 +71,7 @@ def do_express_checkout_payment
       def do_authorization(response)
         Retry.call(no_of_retries: no_of_retires, rescue_errors: ::ActiveMerchant::ConnectionError) {
           ::NewRelic::Agent.increment_metric('Custom/Paypal/Do_Auhtorization') if defined?(NewRelic::Agent)
-          gateway.authorize_transaction(response.params["transaction_id"], convert_amount(cart.total), transaction_entity: "Order", currency: DEFAULT_CURRENCY, payer_id: payer_id)
+          gateway.authorize_transaction(response.params["transaction_id"], convert_amount(payment_transaction.amount), transaction_entity: "Order", currency: DEFAULT_CURRENCY, payer_id: payer_id)
         }
       end
 
diff --git a/lib/paypal_express/generate_summary.rb b/lib/paypal_express/generate_summary.rb
index 62f6735..5055d89 100644
--- a/lib/paypal_express/generate_summary.rb
+++ b/lib/paypal_express/generate_summary.rb
@@ -4,22 +4,25 @@
 module FlexCommerce
   module PaypalExpress
     # @class GenerateSummary
-    # 
+    #
     # This class is used while setting up the paypal for FE
     # It deals with line items total, sub total, tax calculations and
     # Also deals with discounted line items and discounts inorder to send to paypal
-    # 
+    # If gift card was used to pay partial amount and subsequently
+    # gift card amount was passed, it subtracts gift card amount from total 
+    #
     class GenerateSummary
       include ::FlexCommerce::PaypalExpress::Api
-      
-      def initialize(cart: , use_tax: false)
+
+      def initialize(cart: , use_tax: false, gift_card_amount:)
         self.cart = cart
         self.use_tax = use_tax
+        self.gift_card_amount = gift_card_amount
         raise "use_tax is not yet supported.  FlexCommerce::PaypalExpress::GenerateSummary should support it in the future" if use_tax
       end
 
       # @method call
-      # 
+      #
       # @returns an object with subtotal, tax, handling, shipping and items keys
       def call
         {
@@ -34,35 +37,35 @@ def call
       private
 
       # @method subtotal
-      # 
+      #
       # @returns the sum of line items total. This doesnt include any promotions
       def subtotal
         items.sum {|i| i[:quantity] * (i[:amount])}
       end
 
       # @method total
-      # 
+      #
       # @return amount after converting cart total from pence to pounds
       def total
         convert_amount(cart.total)
       end
 
       # @method tax
-      # 
+      #
       # @returns the sum of total line items tax
       def tax
         items.sum {|i| i[:tax] * i[:quantity]}
       end
 
       # @method handling
-      # 
+      #
       # @returns Payment handling charges, which is 0
       def handling
         0
       end
 
       # @method shipping
-      # 
+      #
       # @returns 0 if cart is eligible for free shipping
       # @returns cart.shipping_total, if cart is not eligibl for free shipping
       def shipping
@@ -71,14 +74,14 @@ def shipping
       end
 
       # @mthod items
-      # 
-      # @returns both line items and discounts
+      #
+      # @returns both line items and discounts and gift cards
       def items
-        normal_items + discount_items
+        normal_items + discount_items + gift_cards
       end
 
       # @method discounts
-      # 
+      #
       # @returns [] if there are no discounts on cart
       # @returns Array containing about the total discount amount, if any applied.
       def discount_items
@@ -95,8 +98,26 @@ def discount_items
         ]
       end
 
+      # @method gift_cards
+      #
+      # @returns [] if there are no gift cards on cart
+      # @returns Array containing total gift card amount, if any applied.
+      def gift_cards
+        return [] if gift_card_amount.nil? || gift_card_amount.zero?
+        [
+            {
+                name: "Gift card",
+                number: "NA",
+                quantity: 1,
+                amount: convert_amount(BigDecimal(0) - gift_card_amount),
+                description: "Gift card",
+                tax: 0
+            }
+        ]
+      end
+
       # @method normal_items
-      # 
+      #
       # @returns Object, the normal line items added to cart
       # @note these line items unit prices will be without any discounts
       def normal_items
@@ -112,7 +133,7 @@ def normal_items
         end
       end
 
-      attr_accessor :cart, :use_tax
+      attr_accessor :cart, :use_tax, :gift_card_amount
     end
   end
-end
\ No newline at end of file
+end
diff --git a/lib/paypal_express/process/paypal_params.rb b/lib/paypal_express/process/paypal_params.rb
index 5e7923d..3b3d617 100644
--- a/lib/paypal_express/process/paypal_params.rb
+++ b/lib/paypal_express/process/paypal_params.rb
@@ -9,9 +9,9 @@ class PaypalParams
         include ::FlexCommerce::PaypalExpress::Api
 
         DEFAULT_DESCRIPTION = "Shift Commerce Order".freeze
-        
+
         # @initialize
-        # 
+        #
         # @param {FlexCommerce::PaymentProviderSetup} payment_provider_setup
         # @param {FlexCommerce::Cart} cart
         # @param {Paypal Gateway} [gateway_class = ::ActiveMerchant::Billing::PaypalExpressGateway]
@@ -23,8 +23,9 @@ class PaypalParams
         # @param {FlexCommerce::ShippingMethod} shipping_method_model = FlexCommerce::ShippingMethod
         # @param {boolean} [use_mobile_payments = false]
         # @param {String} [description]
-        # 
-        def initialize(cart:,success_url:, cancel_url:, ip_address:, allow_shipping_change: true, callback_url:, shipping_method_model: FlexCommerce::ShippingMethod, use_mobile_payments: false, description:)
+        # @param {BigDecimal} [gift_card_amount]
+        #
+        def initialize(cart:,success_url:, cancel_url:, ip_address:, allow_shipping_change: true, callback_url:, shipping_method_model: FlexCommerce::ShippingMethod, use_mobile_payments: false, description:, gift_card_amount: nil)
           self.cart = cart
           self.allow_shipping_change = allow_shipping_change
           self.success_url = success_url
@@ -34,6 +35,7 @@ def initialize(cart:,success_url:, cancel_url:, ip_address:, allow_shipping_chan
           self.shipping_method_model = shipping_method_model
           self.use_mobile_payments = use_mobile_payments
           self.description = description
+          self.gift_card_amount = gift_card_amount
         end
 
         def call
@@ -44,7 +46,7 @@ def call
             .merge(shipping_options_params)
         end
 
-        attr_accessor :description, :cart, :success_url, :cancel_url, :ip_address, :allow_shipping_change, :callback_url, :shipping_method_model, :use_mobile_payments
+        attr_accessor :description, :cart, :success_url, :cancel_url, :ip_address, :allow_shipping_change, :callback_url, :shipping_method_model, :use_mobile_payments, :gift_card_amount
 
         private
 
@@ -87,16 +89,16 @@ def paypal_items
 
         def ui_callback_params
           return {} unless allow_shipping_change && shipping_methods.count > 0
-          { 
+          {
             callback_url: callback_url,
             callback_timeout: 6,
             callback_version: 95,
-            max_amount: convert_amount((cart.total * 1.2) + shipping_methods.last.total + shipping_methods.last.tax) 
+            max_amount: convert_amount((cart.total * 1.2) + shipping_methods.last.total + shipping_methods.last.tax)
           }
         end
 
         # @method shipping_methods
-        # 
+        #
         # @returns shipping methods with promotions applied
         def shipping_methods
           @shipping_methods ||= ShippingMethodsForCart.new(cart: cart, shipping_methods: shipping_method_model.all).call.sort_by(&:total)
@@ -115,9 +117,9 @@ def shipping_options_params
         end
 
         def summary
-          @summary ||= GenerateSummary.new(cart: cart).call
+          @summary ||= GenerateSummary.new(cart: cart, gift_card_amount: gift_card_amount).call
         end
       end
     end
   end
-end
\ No newline at end of file
+end
diff --git a/lib/paypal_express/process/response_parser.rb b/lib/paypal_express/process/response_parser.rb
index c2129c1..338f96d 100644
--- a/lib/paypal_express/process/response_parser.rb
+++ b/lib/paypal_express/process/response_parser.rb
@@ -19,7 +19,8 @@ def call
             shipping_method_id: get_shipping_method_details,
             email: get_email_address,
             shipping_address_attributes: get_shipping_address_attributes,
-            billing_address_attributes: get_billing_address_attributes
+            billing_address_attributes: get_billing_address_attributes,
+            payment_details: response.params["PaymentDetails"]
           }
         end
 
diff --git a/lib/paypal_express/setup.rb b/lib/paypal_express/setup.rb
index 726e040..0340cb2 100644
--- a/lib/paypal_express/setup.rb
+++ b/lib/paypal_express/setup.rb
@@ -4,14 +4,14 @@
 module FlexCommerce
   module PaypalExpress
     # @class Setup
-    # 
+    #
     # This is the main class, which talks to ActiveMerchant gem to initiate a transaction using Paypal
     class Setup
       include ::FlexCommerce::PaypalExpress::Api
-      
+
 
       # @initialize
-      # 
+      #
       # @param {FlexCommerce::PaymentProviderSetup} payment_provider_setup
       # @param {FlexCommerce::Cart} cart
       # @param {Paypal Gateway} [gateway_class = ::ActiveMerchant::Billing::PaypalExpressGateway]
@@ -23,12 +23,12 @@ class Setup
       # @param {FlexCommerce::ShippingMethod} shipping_method_model = FlexCommerce::ShippingMethod
       # @param {boolean} [use_mobile_payments = false]
       # @param {String} [description = nil]
-      # 
+      #
       # @note:
       # For `::ActiveMerchant::Billing::PaypalExpressGateway` to work
       # rails-site should include active merchant gem. Ideally this gem should be included in the gemspec.
       # But as we are using custom gem, which is not published to ruby gems, there is no way of including it within this gem dependency
-      def initialize(cart:, gateway_class: ::ActiveMerchant::Billing::PaypalExpressGateway, success_url:, cancel_url:, ip_address:, allow_shipping_change: true, callback_url:, shipping_method_model: FlexCommerce::ShippingMethod, use_mobile_payments: false, description: nil)
+      def initialize(cart:, gateway_class: ::ActiveMerchant::Billing::PaypalExpressGateway, success_url:, cancel_url:, ip_address:, allow_shipping_change: true, callback_url:, shipping_method_model: FlexCommerce::ShippingMethod, use_mobile_payments: false, description: nil, gift_card_amount: BigDecimal(0))
         self.gateway_class = gateway_class
         self.cart = cart
         self.allow_shipping_change = allow_shipping_change
@@ -39,12 +39,13 @@ def initialize(cart:, gateway_class: ::ActiveMerchant::Billing::PaypalExpressGat
         self.shipping_method_model = shipping_method_model
         self.use_mobile_payments = use_mobile_payments
         self.description = description
+        self.gift_card_amount = gift_card_amount
       end
 
       def call
         validate_shipping_method
-        
-        response = gateway.setup_order(convert_amount(cart.total), paypal_params)
+        total_amount = cart.total - gift_card_amount
+        response = gateway.setup_order(convert_amount(total_amount), paypal_params)
         # If paypal setup went fine, redirect to the paypal page
         if response.success?
           PaypalSetup.new(setup_type:  "redirect", redirect_url: gateway.redirect_url_for(response.token, mobile: use_mobile_payments))
@@ -59,7 +60,7 @@ def call
 
       private
 
-      attr_accessor :description, :cart, :gateway_class, :success_url, :cancel_url, :ip_address, :allow_shipping_change, :callback_url, :shipping_method_model, :use_mobile_payments
+      attr_accessor :description, :cart, :gateway_class, :success_url, :cancel_url, :ip_address, :allow_shipping_change, :callback_url, :shipping_method_model, :use_mobile_payments, :gift_card_amount
 
       def paypal_params
         Process::PaypalParams.new(
@@ -71,12 +72,13 @@ def paypal_params
           callback_url: callback_url,
           shipping_method_model: shipping_method_model,
           use_mobile_payments: use_mobile_payments,
-          description: description
+          description: description,
+          gift_card_amount: gift_card_amount
         ).call
       end
 
       # @method shipping_methods
-      # 
+      #
       # @returns shipping methods with promotions applied
       def shipping_methods
         @shipping_methods ||= ShippingMethodsForCart.new(cart: cart, shipping_methods: shipping_method_model.all).call.sort_by(&:total)
diff --git a/lib/paypal_express/shipping_methods_for_cart.rb b/lib/paypal_express/shipping_methods_for_cart.rb
index f5e4e76..5997348 100644
--- a/lib/paypal_express/shipping_methods_for_cart.rb
+++ b/lib/paypal_express/shipping_methods_for_cart.rb
@@ -26,7 +26,9 @@ def call
 
         free_shipping_method_ids.flatten!
         updated_shipping_methods = []
-        shipping_methods.each do |shipping_method|
+        filtered_shipping_methods = shipping_methods.reject { |sm| sm.meta_attribute(:disabled) == 'true' }
+
+        filtered_shipping_methods.each do |shipping_method|
           shipping_method_free = free_shipping_method_ids.include?(shipping_method.id)
           updated_shipping_methods << CartShippingMethod.new(shipping_method, shipping_method_free)
         end
diff --git a/spec/factories/addresses.rb b/spec/factories/addresses.rb
index dfd8114..8713d1b 100644
--- a/spec/factories/addresses.rb
+++ b/spec/factories/addresses.rb
@@ -11,8 +11,8 @@
     state            { Faker::Address.state }
     postcode         { Faker::Address.postcode }
     country          { Faker::Address.country }
-    preferred_billing false
-    preferred_shipping false
+    preferred_billing { false }
+    preferred_shipping { false }
 
   end
   factory :addresses_from_fixture, class: JsonStruct do
@@ -27,4 +27,4 @@
       send(key, value)
     end
   end
-end
\ No newline at end of file
+end
diff --git a/spec/factories/asset_files.rb b/spec/factories/asset_files.rb
index 8cdff27..029d4b9 100644
--- a/spec/factories/asset_files.rb
+++ b/spec/factories/asset_files.rb
@@ -4,10 +4,10 @@
     sequence(:name)             { |n| "asset file name-#{n}" }
     asset_folder_id             { Faker::Number.number(2) }
     sequence(:file_content_filename)  { |n| "asset_file_name_#{n}.png" }
-    file_content_size           106
-    file_content_content_type   "image/png"
+    file_content_size           { 106 }
+    file_content_content_type   { "image/png" }
     image_width                 { Faker::Number.number(4) }
     image_height                { Faker::Number.number(4) }
     reference                   { "#{Faker::Code.isbn}-#{Time.now.nsec}" }
   end
-end
\ No newline at end of file
+end
diff --git a/spec/factories/bundle.rb b/spec/factories/bundle.rb
index bd8d7b1..5656680 100644
--- a/spec/factories/bundle.rb
+++ b/spec/factories/bundle.rb
@@ -8,6 +8,6 @@
   end
 
   factory :bundle_list, parent: :json_api_resource_list do
-    type "bundle"
+    type { "bundle" }
   end
 end
diff --git a/spec/factories/categories.rb b/spec/factories/categories.rb
index 69555dd..8b74a07 100644
--- a/spec/factories/categories.rb
+++ b/spec/factories/categories.rb
@@ -3,7 +3,7 @@
   factory :category, class: klass do
     title       { Faker::Lorem.sentence }
     reference   { rand(1000000000).to_s }
-    category_tree_id "reference:web"
+    category_tree_id { "reference:web" }
   end
   factory :categories_from_fixture, class: JsonStruct do
     obj = JsonStruct.new(JSON.parse(File.read("spec/fixtures/categories/multiple.json")))
@@ -17,4 +17,4 @@
       send(key, value)
     end
   end
-end
\ No newline at end of file
+end
diff --git a/spec/factories/variants.rb b/spec/factories/variants.rb
index 04fa9b3..92970be 100644
--- a/spec/factories/variants.rb
+++ b/spec/factories/variants.rb
@@ -5,6 +5,6 @@
     description { Faker::Lorem.sentence }
     sku { Faker::Code.ean }
     reference { Faker::Lorem.words(3).join("-") }
-    stock_level 100
+    stock_level { 100 }
   end
 end
diff --git a/spec/factories/webhook.rb b/spec/factories/webhook.rb
index aefa67f..be0e385 100644
--- a/spec/factories/webhook.rb
+++ b/spec/factories/webhook.rb
@@ -3,7 +3,7 @@
   factory :webhook, class: klass do
     title { Faker::Lorem.words(3).join(" ") }
     event { "order_created" }
-    request_url "https://example.com/bla"
-    request_headers ({ "X-Token" => "test" })
+    request_url { "https://example.com/bla" }
+    request_headers {{ "X-Token" => "test" }}
   end
 end
diff --git a/spec/integration/oms/customer_order.rb b/spec/integration/oms/customer_order.rb
new file mode 100644
index 0000000..84cbd7e
--- /dev/null
+++ b/spec/integration/oms/customer_order.rb
@@ -0,0 +1,14 @@
+require "spec_helper"
+require "flex_commerce_api"
+require "uri"
+
+
+RSpec.describe "OMS Order History" do
+  include_context "global context"
+
+  let(:subject_class) { ::FlexCommerce::CustomerOrder }
+
+  context "Fetching Order history via OMS" do
+    subject_class.fetch_orders(customer_reference: "12345")
+  end
+end
\ No newline at end of file
diff --git a/spec/lib/paypal_express/auth_spec.rb b/spec/lib/paypal_express/auth_spec.rb
index 500361e..f25943b 100644
--- a/spec/lib/paypal_express/auth_spec.rb
+++ b/spec/lib/paypal_express/auth_spec.rb
@@ -4,11 +4,11 @@
   include ActiveSupport::NumberHelper
   include_context "context store"
   include_context "housekeeping"
-  
+
   let(:token) { "fake-token" }
   let(:payer_id) { "fake-payer-id" }
   let(:cart) { build_stubbed(:cart, total: 100) }
-  let(:transaction) { 
+  let(:transaction) {
     to_clean.transaction = FlexCommerce::PaymentTransaction.create(
       cart_id: cart.id,
       gateway_response: {
@@ -28,7 +28,7 @@
     cart.billing_address.freeze
     cart.freeze
   end
-  
+
   subject { described_class.new(cart: cart, token: token, payer_id: payer_id, payment_transaction: transaction) }
 
   shared_context "mocked active merchant" do |expect_login: true, test_mode: true|
@@ -85,7 +85,7 @@
 
     context "happy path in production" do
       include_context "mocked active merchant", test_mode: false
-      
+
       before(:each) do
         expect(active_merchant_gateway).to receive(:order).with(convert_amount(cart.total), token: token, payer_id: payer_id, currency: "GBP").and_return order_response
         expect(active_merchant_gateway).to receive(:authorize_transaction).with(transaction_id, convert_amount(cart.total), transaction_entity: "Order", payer_id: payer_id, currency: "GBP").and_return authorize_order_response
@@ -99,7 +99,7 @@
 
     context "with error scenarios" do
       include_context "mocked active merchant"
-      
+
       it "should mark the transactions gateway_response as invalid when failure is recoverable in order stage" do
         order_response = instance_double "ActiveMerchant::Billing::PaypalExpressGateway", "order_response", params: {"error_codes" => "10410", "message" => "Invalid token", "ack" => "Failure", "Ack" => "Failure"}, success?: false
         expect(active_merchant_gateway).to receive(:order).with(convert_amount(cart.total), token: token, payer_id: payer_id, currency: "GBP").and_return order_response
diff --git a/spec/lib/paypal_express/generate_summary_spec.rb b/spec/lib/paypal_express/generate_summary_spec.rb
index 6f90985..3f1a21a 100644
--- a/spec/lib/paypal_express/generate_summary_spec.rb
+++ b/spec/lib/paypal_express/generate_summary_spec.rb
@@ -5,10 +5,11 @@ def convert_amount(amt)
     (amt * 100).to_i
   end
   context "without tax" do
-    subject { described_class.new(cart: cart) }
     shared_examples_for "a summary from a cart with tax ignored" do
       it "should have the correct subtotal" do
-        expect(subject.call).to include subtotal: convert_amount(line_items.sum(&:total))
+        # gift card amount is deducted from subtotal if gift card used
+        subtotal = line_items.sum(&:total) - gift_card_amount
+        expect(subject.call).to include subtotal: convert_amount(subtotal)
       end
       it "should have zero tax" do
         expect(subject.call).to include tax: 0
@@ -20,6 +21,7 @@ def convert_amount(amt)
         expect(subject.call).to include shipping: convert_amount(shipping_total)
       end
     end
+
     shared_examples_for "paypal items" do
       it "should have the correct items - amount and quantity" do
         expect(paypal_items).to match_array(line_items.map { |li| hash_including(amount: convert_amount(li.unit_price), quantity: li.unit_quantity) })
@@ -34,17 +36,34 @@ def convert_amount(amt)
         expect(paypal_items).to match_array(line_items.map { |li| hash_including(number: li.item.sku) })
       end
     end
+
+    shared_examples_for "non discounted line items" do
+      let(:gift_card_amount) { BigDecimal(0) }
+      subject { described_class.new(cart: cart, gift_card_amount: gift_card_amount) }
+      let(:paypal_items) { subject.call[:items] }
+      include_examples "paypal items"
+    end
+
     shared_examples_for "discounted line items" do
+      let(:gift_card_amount) { BigDecimal(0) }
+      subject { described_class.new(cart: cart, gift_card_amount: gift_card_amount) }
       let(:paypal_items) { subject.call[:items][0...-1] }
       include_examples "paypal items"
       it "should have the last item as special discount item" do
         expect(subject.call).to include(items: array_including(hash_including(amount: convert_amount(BigDecimal(0) - cart.total_discount))))
       end
     end
-    shared_examples_for "non discounted line items" do
-      let(:paypal_items) { subject.call[:items] }
+
+    shared_examples_for "line items partially paid with gift cards" do
+      let(:gift_card_amount) { BigDecimal(10) }
+      subject { described_class.new(cart: cart, gift_card_amount: gift_card_amount) }
+      let(:paypal_items) { subject.call[:items][0...-1] }
       include_examples "paypal items"
+      it "should have the last item as gift card item" do
+        expect(subject.call).to include(items: array_including(hash_including(amount: convert_amount(BigDecimal(0) - gift_card_amount))))
+      end
     end
+
     context "with no shipping" do
       let(:shipping_total) { BigDecimal(0) }
       context "with no discounts" do
@@ -56,6 +75,17 @@ def convert_amount(amt)
         include_examples "a summary from a cart with tax ignored"
         include_examples "non discounted line items"
       end
+
+      context "with gift card" do
+        let(:cart) { double(:cart, free_shipping: false, line_items: line_items, shipping_total: shipping_total, total: line_items.sum(&:total) + shipping_total, total_discount: line_item_discount * line_items.length) }
+        let(:line_item_discount) { BigDecimal(0) }
+        let(:item) { 5.times.map { |n| double(:variant, sku: "sku_#{n}") } }
+        let(:line_items) { 5.times.map { |n| double(:line_item, unit_price: BigDecimal(1.67, 12), item: item[n], unit_quantity: 3, total: BigDecimal(5.01, 12), title: "Line item #{n}", tax: BigDecimal(0)) } }
+
+        include_examples "a summary from a cart with tax ignored"
+        include_examples "line items partially paid with gift cards"
+      end
+
       context "with line item discounts" do
         let(:cart) { double(:cart, free_shipping: false, line_items: line_items, shipping_total: shipping_total, total: line_items.sum(&:total) + shipping_total, total_discount: line_item_discount * line_items.length) }
         let(:line_item_discount) { BigDecimal(0.79, 12) }
@@ -65,6 +95,7 @@ def convert_amount(amt)
         include_examples "discounted line items"
       end
     end
+
     context "with shipping" do
       let(:shipping_total) { BigDecimal(3.99, 12) }
       context "with no discounts" do
@@ -75,6 +106,16 @@ def convert_amount(amt)
         include_examples "a summary from a cart with tax ignored"
         include_examples "non discounted line items"
       end
+
+      context "with gift card" do
+        let(:cart) { double(:cart, free_shipping: false, line_items: line_items, shipping_total: shipping_total, total: line_items.sum(&:total) + shipping_total, total_discount: line_item_discount * line_items.length) }
+        let(:line_item_discount) { BigDecimal(0) }
+        let(:item) { 5.times.map { |n| double(:variant, sku: "sku_#{n}") } }
+        let(:line_items) { 5.times.map { |n| double(:line_ttem, unit_price: BigDecimal(1.67, 12), item: item[n], unit_quantity: 3, total: BigDecimal(5.01, 12), title: "Line item #{n}", tax: BigDecimal(0)) } }
+        include_examples "a summary from a cart with tax ignored"
+        include_examples "line items partially paid with gift cards"
+      end
+
       context "with line item discounts" do
         let(:cart) { double(:cart, free_shipping: false, line_items: line_items, shipping_total: shipping_total, total: line_items.sum(&:total) + shipping_total, total_discount: line_item_discount * line_items.length) }
         let(:line_item_discount) { BigDecimal(0.79, 12) }