diff --git a/app/models/spree/calculator/default_tax.rb b/app/models/calculator/default_tax.rb
similarity index 98%
rename from app/models/spree/calculator/default_tax.rb
rename to app/models/calculator/default_tax.rb
index 8a4e1fa053..1910990945 100644
--- a/app/models/spree/calculator/default_tax.rb
+++ b/app/models/calculator/default_tax.rb
@@ -5,7 +5,7 @@ require 'open_food_network/enterprise_fee_calculator'
 
 module Spree
   module Calculator
-    class DefaultTax < Calculator
+    class DefaultTax < Spree::Calculator
       def self.description
         Spree.t(:default_tax)
       end
diff --git a/app/models/calculator/flat_percent_item_total.rb b/app/models/calculator/flat_percent_item_total.rb
new file mode 100644
index 0000000000..79c2f1f400
--- /dev/null
+++ b/app/models/calculator/flat_percent_item_total.rb
@@ -0,0 +1,24 @@
+# frozen_string_literal: false
+
+require_dependency 'spree/calculator'
+require 'spree/localized_number'
+
+module Calculator
+  class FlatPercentItemTotal < Spree::Calculator
+    extend Spree::LocalizedNumber
+
+    preference :flat_percent, :decimal, default: 0
+
+    localize_number :preferred_flat_percent
+
+    def self.description
+      Spree.t(:flat_percent)
+    end
+
+    def compute(object)
+      item_total = line_items_for(object).map(&:amount).sum
+      value = item_total * BigDecimal(preferred_flat_percent.to_s) / 100.0
+      (value * 100).round.to_f / 100
+    end
+  end
+end
diff --git a/app/models/calculator/flat_rate.rb b/app/models/calculator/flat_rate.rb
new file mode 100644
index 0000000000..d8bc14ca8f
--- /dev/null
+++ b/app/models/calculator/flat_rate.rb
@@ -0,0 +1,23 @@
+# frozen_string_literal: false
+
+require_dependency 'spree/calculator'
+require 'spree/localized_number'
+
+module Calculator
+  class FlatRate < Spree::Calculator
+    extend Spree::LocalizedNumber
+
+    preference :amount, :decimal, default: 0
+    preference :currency, :string, default: Spree::Config[:currency]
+
+    localize_number :preferred_amount
+
+    def self.description
+      I18n.t(:flat_rate_per_order)
+    end
+
+    def compute(_object = nil)
+      preferred_amount
+    end
+  end
+end
diff --git a/app/models/calculator/flexi_rate.rb b/app/models/calculator/flexi_rate.rb
new file mode 100644
index 0000000000..b7e7974c3b
--- /dev/null
+++ b/app/models/calculator/flexi_rate.rb
@@ -0,0 +1,43 @@
+# frozen_string_literal: false
+
+require_dependency 'spree/calculator'
+require 'spree/localized_number'
+
+module Calculator
+  class FlexiRate < Spree::Calculator
+    extend Spree::LocalizedNumber
+
+    preference :first_item,      :decimal, default: 0.0
+    preference :additional_item, :decimal, default: 0.0
+    preference :max_items,       :integer, default: 0
+    preference :currency,        :string,  default: Spree::Config[:currency]
+
+    localize_number :preferred_first_item,
+                    :preferred_additional_item
+
+    def self.description
+      I18n.t(:flexible_rate)
+    end
+
+    def self.available?(_object)
+      true
+    end
+
+    def compute(object)
+      sum = 0
+      max = preferred_max_items.to_i
+      items_count = line_items_for(object).map(&:quantity).sum
+
+      # check max value to avoid divide by 0 errors
+      unless max.zero?
+        if items_count > max
+          sum += (max - 1) * preferred_additional_item.to_f + preferred_first_item.to_f
+        elsif items_count <= max
+          sum += (items_count - 1) * preferred_additional_item.to_f + preferred_first_item.to_f
+        end
+      end
+
+      sum
+    end
+  end
+end
diff --git a/app/models/calculator/per_item.rb b/app/models/calculator/per_item.rb
new file mode 100644
index 0000000000..49b2df35c4
--- /dev/null
+++ b/app/models/calculator/per_item.rb
@@ -0,0 +1,29 @@
+# frozen_string_literal: false
+
+require_dependency 'spree/calculator'
+require 'spree/localized_number'
+
+module Calculator
+  class PerItem < Spree::Calculator
+    extend Spree::LocalizedNumber
+
+    preference :amount, :decimal, default: 0
+    preference :currency, :string, default: Spree::Config[:currency]
+
+    localize_number :preferred_amount
+
+    def self.description
+      I18n.t(:flat_rate_per_item)
+    end
+
+    def compute(object = nil)
+      return 0 if object.nil?
+
+      number_of_line_items = line_items_for(object).reduce(0) do |sum, line_item|
+        value_to_add = line_item.quantity
+        sum + value_to_add
+      end
+      preferred_amount * number_of_line_items
+    end
+  end
+end
diff --git a/app/models/calculator/price_sack.rb b/app/models/calculator/price_sack.rb
new file mode 100644
index 0000000000..cb6d185bd6
--- /dev/null
+++ b/app/models/calculator/price_sack.rb
@@ -0,0 +1,38 @@
+# frozen_string_literal: false
+
+require_dependency 'spree/calculator'
+# For #to_d method on Ruby 1.8
+require 'bigdecimal/util'
+require 'spree/localized_number'
+
+module Calculator
+  class PriceSack < Spree::Calculator
+    extend Spree::LocalizedNumber
+
+    preference :minimal_amount, :decimal, default: 0
+    preference :normal_amount, :decimal, default: 0
+    preference :discount_amount, :decimal, default: 0
+    preference :currency, :string, default: Spree::Config[:currency]
+
+    localize_number :preferred_minimal_amount,
+                    :preferred_normal_amount,
+                    :preferred_discount_amount
+
+    def self.description
+      I18n.t(:price_sack)
+    end
+
+    def compute(object)
+      min = preferred_minimal_amount.to_f
+      order_amount = line_items_for(object).map { |x| x.price * x.quantity }.sum
+
+      if order_amount < min
+        cost = preferred_normal_amount.to_f
+      elsif order_amount >= min
+        cost = preferred_discount_amount.to_f
+      end
+
+      cost
+    end
+  end
+end
diff --git a/app/models/enterprise_fee.rb b/app/models/enterprise_fee.rb
index bbcafa01dc..1bea6701e7 100644
--- a/app/models/enterprise_fee.rb
+++ b/app/models/enterprise_fee.rb
@@ -11,7 +11,7 @@ class EnterpriseFee < ActiveRecord::Base
   has_many :exchanges, through: :exchange_fees
 
   FEE_TYPES = %w(packing transport admin sales fundraising).freeze
-  PER_ORDER_CALCULATORS = ['Spree::Calculator::FlatRate', 'Spree::Calculator::FlexiRate', 'Spree::Calculator::PriceSack'].freeze
+  PER_ORDER_CALCULATORS = ['Calculator::FlatRate', 'Calculator::FlexiRate', 'Calculator::PriceSack'].freeze
 
   validates :fee_type, inclusion: { in: FEE_TYPES }
   validates :name, presence: true
diff --git a/app/models/spree/calculator/flat_percent_item_total.rb b/app/models/spree/calculator/flat_percent_item_total.rb
deleted file mode 100644
index 0d2dc7e0db..0000000000
--- a/app/models/spree/calculator/flat_percent_item_total.rb
+++ /dev/null
@@ -1,26 +0,0 @@
-# frozen_string_literal: false
-
-require_dependency 'spree/calculator'
-require 'spree/localized_number'
-
-module Spree
-  module Calculator
-    class FlatPercentItemTotal < Calculator
-      extend Spree::LocalizedNumber
-
-      preference :flat_percent, :decimal, default: 0
-
-      localize_number :preferred_flat_percent
-
-      def self.description
-        Spree.t(:flat_percent)
-      end
-
-      def compute(object)
-        item_total = line_items_for(object).map(&:amount).sum
-        value = item_total * BigDecimal(preferred_flat_percent.to_s) / 100.0
-        (value * 100).round.to_f / 100
-      end
-    end
-  end
-end
diff --git a/app/models/spree/calculator/flat_rate.rb b/app/models/spree/calculator/flat_rate.rb
deleted file mode 100644
index a2d6d9c55b..0000000000
--- a/app/models/spree/calculator/flat_rate.rb
+++ /dev/null
@@ -1,25 +0,0 @@
-# frozen_string_literal: false
-
-require_dependency 'spree/calculator'
-require 'spree/localized_number'
-
-module Spree
-  module Calculator
-    class FlatRate < Calculator
-      extend Spree::LocalizedNumber
-
-      preference :amount, :decimal, default: 0
-      preference :currency, :string, default: Spree::Config[:currency]
-
-      localize_number :preferred_amount
-
-      def self.description
-        I18n.t(:flat_rate_per_order)
-      end
-
-      def compute(_object = nil)
-        preferred_amount
-      end
-    end
-  end
-end
diff --git a/app/models/spree/calculator/flexi_rate.rb b/app/models/spree/calculator/flexi_rate.rb
deleted file mode 100644
index 78db514970..0000000000
--- a/app/models/spree/calculator/flexi_rate.rb
+++ /dev/null
@@ -1,45 +0,0 @@
-# frozen_string_literal: false
-
-require_dependency 'spree/calculator'
-require 'spree/localized_number'
-
-module Spree
-  module Calculator
-    class FlexiRate < Calculator
-      extend Spree::LocalizedNumber
-
-      preference :first_item,      :decimal, default: 0.0
-      preference :additional_item, :decimal, default: 0.0
-      preference :max_items,       :integer, default: 0
-      preference :currency,        :string,  default: Spree::Config[:currency]
-
-      localize_number :preferred_first_item,
-                      :preferred_additional_item
-
-      def self.description
-        I18n.t(:flexible_rate)
-      end
-
-      def self.available?(_object)
-        true
-      end
-
-      def compute(object)
-        sum = 0
-        max = preferred_max_items.to_i
-        items_count = line_items_for(object).map(&:quantity).sum
-
-        # check max value to avoid divide by 0 errors
-        unless max.zero?
-          if items_count > max
-            sum += (max - 1) * preferred_additional_item.to_f + preferred_first_item.to_f
-          elsif items_count <= max
-            sum += (items_count - 1) * preferred_additional_item.to_f + preferred_first_item.to_f
-          end
-        end
-
-        sum
-      end
-    end
-  end
-end
diff --git a/app/models/spree/calculator/per_item.rb b/app/models/spree/calculator/per_item.rb
deleted file mode 100644
index fdd9aa4a5b..0000000000
--- a/app/models/spree/calculator/per_item.rb
+++ /dev/null
@@ -1,31 +0,0 @@
-# frozen_string_literal: false
-
-require_dependency 'spree/calculator'
-require 'spree/localized_number'
-
-module Spree
-  module Calculator
-    class PerItem < Calculator
-      extend Spree::LocalizedNumber
-
-      preference :amount, :decimal, default: 0
-      preference :currency, :string, default: Spree::Config[:currency]
-
-      localize_number :preferred_amount
-
-      def self.description
-        I18n.t(:flat_rate_per_item)
-      end
-
-      def compute(object = nil)
-        return 0 if object.nil?
-
-        number_of_line_items = line_items_for(object).reduce(0) do |sum, line_item|
-          value_to_add = line_item.quantity
-          sum + value_to_add
-        end
-        preferred_amount * number_of_line_items
-      end
-    end
-  end
-end
diff --git a/app/models/spree/calculator/price_sack.rb b/app/models/spree/calculator/price_sack.rb
deleted file mode 100644
index ac6bf0b653..0000000000
--- a/app/models/spree/calculator/price_sack.rb
+++ /dev/null
@@ -1,40 +0,0 @@
-# frozen_string_literal: false
-
-require_dependency 'spree/calculator'
-# For #to_d method on Ruby 1.8
-require 'bigdecimal/util'
-require 'spree/localized_number'
-
-module Spree
-  module Calculator
-    class PriceSack < Calculator
-      extend Spree::LocalizedNumber
-
-      preference :minimal_amount, :decimal, default: 0
-      preference :normal_amount, :decimal, default: 0
-      preference :discount_amount, :decimal, default: 0
-      preference :currency, :string, default: Spree::Config[:currency]
-
-      localize_number :preferred_minimal_amount,
-                      :preferred_normal_amount,
-                      :preferred_discount_amount
-
-      def self.description
-        I18n.t(:price_sack)
-      end
-
-      def compute(object)
-        min = preferred_minimal_amount.to_f
-        order_amount = line_items_for(object).map { |x| x.price * x.quantity }.sum
-
-        if order_amount < min
-          cost = preferred_normal_amount.to_f
-        elsif order_amount >= min
-          cost = preferred_discount_amount.to_f
-        end
-
-        cost
-      end
-    end
-  end
-end
diff --git a/app/models/spree/payment_method_decorator.rb b/app/models/spree/payment_method_decorator.rb
index 3da3919bf0..4c2770daea 100644
--- a/app/models/spree/payment_method_decorator.rb
+++ b/app/models/spree/payment_method_decorator.rb
@@ -49,7 +49,7 @@ Spree::PaymentMethod.class_eval do
       self.class.include Spree::Core::CalculatedAdjustments
     end
 
-    self.calculator ||= Spree::Calculator::FlatRate.new(preferred_amount: 0)
+    self.calculator ||= Calculator::FlatRate.new(preferred_amount: 0)
   end
 
   def has_distributor?(distributor)
diff --git a/config/application.rb b/config/application.rb
index 547795ea5f..3860b0b928 100644
--- a/config/application.rb
+++ b/config/application.rb
@@ -49,30 +49,30 @@ module Openfoodnetwork
     # Register Spree calculators
     initializer 'spree.register.calculators' do |app|
       app.config.spree.calculators.shipping_methods = [
-        Spree::Calculator::FlatPercentItemTotal,
-        Spree::Calculator::FlatRate,
-        Spree::Calculator::FlexiRate,
-        Spree::Calculator::PerItem,
-        Spree::Calculator::PriceSack,
+        Calculator::FlatPercentItemTotal,
+        Calculator::FlatRate,
+        Calculator::FlexiRate,
+        Calculator::PerItem,
+        Calculator::PriceSack,
         Calculator::Weight
       ]
 
       app.config.spree.calculators.add_class('enterprise_fees')
       config.spree.calculators.enterprise_fees = [
         Calculator::FlatPercentPerItem,
-        Spree::Calculator::FlatRate,
-        Spree::Calculator::FlexiRate,
-        Spree::Calculator::PerItem,
-        Spree::Calculator::PriceSack,
+        Calculator::FlatRate,
+        Calculator::FlexiRate,
+        Calculator::PerItem,
+        Calculator::PriceSack,
         Calculator::Weight
       ]
       app.config.spree.calculators.add_class('payment_methods')
       config.spree.calculators.payment_methods = [
-        Spree::Calculator::FlatPercentItemTotal,
-        Spree::Calculator::FlatRate,
-        Spree::Calculator::FlexiRate,
-        Spree::Calculator::PerItem,
-        Spree::Calculator::PriceSack
+        Calculator::FlatPercentItemTotal,
+        Calculator::FlatRate,
+        Calculator::FlexiRate,
+        Calculator::PerItem,
+        Calculator::PriceSack
       ]
     end
 
diff --git a/engines/order_management/spec/services/order_management/subscriptions/estimator_spec.rb b/engines/order_management/spec/services/order_management/subscriptions/estimator_spec.rb
index 9e7bd15c06..ad14253a98 100644
--- a/engines/order_management/spec/services/order_management/subscriptions/estimator_spec.rb
+++ b/engines/order_management/spec/services/order_management/subscriptions/estimator_spec.rb
@@ -99,11 +99,11 @@ module OrderManagement
         context "using flat rate calculators" do
           let(:shipping_method) {
             create(:shipping_method,
-                   calculator: Spree::Calculator::FlatRate.new(preferred_amount: 12.34))
+                   calculator: Calculator::FlatRate.new(preferred_amount: 12.34))
           }
           let(:payment_method) {
             create(:payment_method,
-                   calculator: Spree::Calculator::FlatRate.new(preferred_amount: 9.12))
+                   calculator: Calculator::FlatRate.new(preferred_amount: 9.12))
           }
 
           it "calculates fees based on the rates provided" do
@@ -116,13 +116,13 @@ module OrderManagement
         context "using flat percent item total calculators" do
           let(:shipping_method) {
             create(:shipping_method,
-                   calculator: Spree::Calculator::FlatPercentItemTotal.new(
+                   calculator: Calculator::FlatPercentItemTotal.new(
                      preferred_flat_percent: 10
                    ))
           }
           let(:payment_method) {
             create(:payment_method,
-                   calculator: Spree::Calculator::FlatPercentItemTotal.new(
+                   calculator: Calculator::FlatPercentItemTotal.new(
                      preferred_flat_percent: 20
                    ))
           }
@@ -154,11 +154,11 @@ module OrderManagement
         context "using per item calculators" do
           let(:shipping_method) {
             create(:shipping_method,
-                   calculator: Spree::Calculator::PerItem.new(preferred_amount: 1.2))
+                   calculator: Calculator::PerItem.new(preferred_amount: 1.2))
           }
           let(:payment_method) {
             create(:payment_method,
-                   calculator: Spree::Calculator::PerItem.new(preferred_amount: 0.3))
+                   calculator: Calculator::PerItem.new(preferred_amount: 0.3))
           }
 
           it "calculates fees based on the number of items and rate provided" do
diff --git a/lib/tasks/sample_data/payment_method_factory.rb b/lib/tasks/sample_data/payment_method_factory.rb
index 27dc5404cf..b8430c3d96 100644
--- a/lib/tasks/sample_data/payment_method_factory.rb
+++ b/lib/tasks/sample_data/payment_method_factory.rb
@@ -29,7 +29,7 @@ class PaymentMethodFactory
       enterprise,
       "Cash on collection",
       "Pay on collection!",
-      Spree::Calculator::FlatRate.new
+      Calculator::FlatRate.new
     )
   end
 
@@ -39,7 +39,7 @@ class PaymentMethodFactory
       enterprise,
       "Credit card (fake)",
       "We charge 1%, but won't ask for your details. ;-)",
-      Spree::Calculator::FlatPercentItemTotal.new(preferred_flat_percent: 1)
+      Calculator::FlatPercentItemTotal.new(preferred_flat_percent: 1)
     )
   end
 
diff --git a/lib/tasks/sample_data/shipping_method_factory.rb b/lib/tasks/sample_data/shipping_method_factory.rb
index 5bfb382318..889765775a 100644
--- a/lib/tasks/sample_data/shipping_method_factory.rb
+++ b/lib/tasks/sample_data/shipping_method_factory.rb
@@ -39,7 +39,7 @@ class ShippingMethodFactory
       name: "Home delivery #{enterprise.name}",
       description: "yummy food delivered at your door",
       require_ship_address: true,
-      calculator_type: "Spree::Calculator::FlatRate"
+      calculator_type: "Calculator::FlatRate"
     )
     delivery.calculator.preferred_amount = 2
     delivery.calculator.save!
diff --git a/spec/controllers/admin/enterprises_controller_spec.rb b/spec/controllers/admin/enterprises_controller_spec.rb
index 054b37e2de..78678e03e2 100644
--- a/spec/controllers/admin/enterprises_controller_spec.rb
+++ b/spec/controllers/admin/enterprises_controller_spec.rb
@@ -192,7 +192,7 @@ describe Admin::EnterprisesController, type: :controller do
                             id: tag_rule,
                             type: "TagRule::DiscountOrder",
                             preferred_customer_tags: "some,new,tags",
-                            calculator_type: "Spree::Calculator::FlatPercentItemTotal",
+                            calculator_type: "Calculator::FlatPercentItemTotal",
                             calculator_attributes: { id: tag_rule.calculator.id, preferred_flat_percent: "15" }
                           }
                         }
@@ -211,7 +211,7 @@ describe Admin::EnterprisesController, type: :controller do
                             id: "",
                             type: "TagRule::DiscountOrder",
                             preferred_customer_tags: "tags,are,awesome",
-                            calculator_type: "Spree::Calculator::FlatPercentItemTotal",
+                            calculator_type: "Calculator::FlatPercentItemTotal",
                             calculator_attributes: { id: "", preferred_flat_percent: "24" }
                           }
                         }
diff --git a/spec/controllers/spree/admin/adjustments_controller_spec.rb b/spec/controllers/spree/admin/adjustments_controller_spec.rb
index fc60008c00..4ad02b73c7 100644
--- a/spec/controllers/spree/admin/adjustments_controller_spec.rb
+++ b/spec/controllers/spree/admin/adjustments_controller_spec.rb
@@ -8,7 +8,7 @@ module Spree
 
     describe "setting included tax" do
       let(:order) { create(:order) }
-      let(:tax_rate) { create(:tax_rate, amount: 0.1, calculator: Spree::Calculator::DefaultTax.new) }
+      let(:tax_rate) { create(:tax_rate, amount: 0.1, calculator: Calculator::DefaultTax.new) }
 
       describe "creating an adjustment" do
         it "sets included tax to zero when no tax rate is specified" do
diff --git a/spec/controllers/spree/admin/shipping_methods_controller_spec.rb b/spec/controllers/spree/admin/shipping_methods_controller_spec.rb
index 531d01c11e..105d55563c 100644
--- a/spec/controllers/spree/admin/shipping_methods_controller_spec.rb
+++ b/spec/controllers/spree/admin/shipping_methods_controller_spec.rb
@@ -50,7 +50,7 @@ describe Spree::Admin::ShippingMethodsController, type: :controller do
     end
 
     it "updates details of a FlexiRate calculator" do
-      shipping_method.calculator = Spree::Calculator::FlexiRate.new(calculable: shipping_method)
+      shipping_method.calculator = Calculator::FlexiRate.new(calculable: shipping_method)
       params[:shipping_method][:calculator_attributes][:preferred_first_item] = 10
       params[:shipping_method][:calculator_attributes][:preferred_additional_item] = 20
       params[:shipping_method][:calculator_attributes][:preferred_max_items] = 30
@@ -63,7 +63,7 @@ describe Spree::Admin::ShippingMethodsController, type: :controller do
     end
 
     it "updates details of a PriceSack calculator" do
-      shipping_method.calculator = Spree::Calculator::PriceSack.new(calculable: shipping_method)
+      shipping_method.calculator = Calculator::PriceSack.new(calculable: shipping_method)
       params[:shipping_method][:calculator_attributes][:preferred_minimal_amount] = 10
       params[:shipping_method][:calculator_attributes][:preferred_normal_amount] = 20
       params[:shipping_method][:calculator_attributes][:preferred_discount_amount] = 30
diff --git a/spec/factories/calculated_adjustment_factory.rb b/spec/factories/calculated_adjustment_factory.rb
index 3e9c6f5cc2..5654b62746 100644
--- a/spec/factories/calculated_adjustment_factory.rb
+++ b/spec/factories/calculated_adjustment_factory.rb
@@ -1,5 +1,5 @@
 FactoryBot.define do
-  factory :calculator_flat_rate, class: Spree::Calculator::FlatRate do
+  factory :calculator_flat_rate, class: Calculator::FlatRate do
     preferred_amount { generate(:calculator_amount) }
   end
 end
diff --git a/spec/factories/calculator_factory.rb b/spec/factories/calculator_factory.rb
index 25dd9b0a13..0c8acaf3e5 100644
--- a/spec/factories/calculator_factory.rb
+++ b/spec/factories/calculator_factory.rb
@@ -1,6 +1,6 @@
 FactoryBot.define do
   sequence(:calculator_amount)
-  factory :calculator_per_item, class: Spree::Calculator::PerItem do
+  factory :calculator_per_item, class: Calculator::PerItem do
     preferred_amount { generate(:calculator_amount) }
   end
 
diff --git a/spec/factories/product_factory.rb b/spec/factories/product_factory.rb
index e546abbac4..3ca3fdb77e 100644
--- a/spec/factories/product_factory.rb
+++ b/spec/factories/product_factory.rb
@@ -36,7 +36,7 @@ FactoryBot.define do
       create(:tax_rate, amount: proxy.tax_rate_amount,
                         tax_category: product.tax_category,
                         included_in_price: true,
-                        calculator: Spree::Calculator::DefaultTax.new,
+                        calculator: Calculator::DefaultTax.new,
                         zone: proxy.zone,
                         name: proxy.tax_rate_name)
     end
diff --git a/spec/factories/shipping_method_factory.rb b/spec/factories/shipping_method_factory.rb
index 516dfb6b66..87cec39be9 100644
--- a/spec/factories/shipping_method_factory.rb
+++ b/spec/factories/shipping_method_factory.rb
@@ -9,13 +9,13 @@ FactoryBot.define do
     end
 
     trait :flat_rate do
-      calculator { Spree::Calculator::FlatRate.new(preferred_amount: 50.0) }
+      calculator { Calculator::FlatRate.new(preferred_amount: 50.0) }
     end
 
     trait :expensive_name do
       name { "Shipping" }
       description { "Expensive" }
-      calculator { Spree::Calculator::FlatRate.new(preferred_amount: 100.55) }
+      calculator { Calculator::FlatRate.new(preferred_amount: 100.55) }
     end
 
     trait :distributor do
diff --git a/spec/factories/tag_rule_factory.rb b/spec/factories/tag_rule_factory.rb
index 9663913820..4a4f5b1130 100644
--- a/spec/factories/tag_rule_factory.rb
+++ b/spec/factories/tag_rule_factory.rb
@@ -18,7 +18,7 @@ FactoryBot.define do
   factory :tag_rule, class: TagRule::DiscountOrder do
     enterprise { FactoryBot.create :distributor_enterprise }
     before(:create) do |tr|
-      tr.calculator = Spree::Calculator::FlatPercentItemTotal.new(calculable: tr)
+      tr.calculator = Calculator::FlatPercentItemTotal.new(calculable: tr)
     end
   end
 end
diff --git a/spec/features/admin/payments_spec.rb b/spec/features/admin/payments_spec.rb
index 2ea666f121..adce888db2 100644
--- a/spec/features/admin/payments_spec.rb
+++ b/spec/features/admin/payments_spec.rb
@@ -21,7 +21,7 @@ feature '
 
       # This calculator doesn't handle a `nil` order well.
       # That has been useful in finding bugs. ;-)
-      payment_method.calculator = Spree::Calculator::FlatPercentItemTotal.new
+      payment_method.calculator = Calculator::FlatPercentItemTotal.new
       payment_method.save!
     end
 
diff --git a/spec/features/admin/reports_spec.rb b/spec/features/admin/reports_spec.rb
index 5ebd118fd7..b8eb70f010 100644
--- a/spec/features/admin/reports_spec.rb
+++ b/spec/features/admin/reports_spec.rb
@@ -170,7 +170,7 @@ feature '
     let(:user1) { create_enterprise_user enterprises: [distributor1] }
     let(:user2) { create_enterprise_user enterprises: [distributor2] }
     let!(:shipping_method) { create(:shipping_method_with, :expensive_name, distributors: [distributor1]) }
-    let(:enterprise_fee) { create(:enterprise_fee, enterprise: user1.enterprises.first, tax_category: product2.tax_category, calculator: Spree::Calculator::FlatRate.new(preferred_amount: 120.0)) }
+    let(:enterprise_fee) { create(:enterprise_fee, enterprise: user1.enterprises.first, tax_category: product2.tax_category, calculator: Calculator::FlatRate.new(preferred_amount: 120.0)) }
     let(:order_cycle) { create(:simple_order_cycle, coordinator: distributor1, coordinator_fees: [enterprise_fee], distributors: [distributor1], variants: [product1.master]) }
 
     let!(:zone) { create(:zone_with_member) }
@@ -384,8 +384,8 @@ feature '
     let(:shipping_method) { create(:shipping_method_with, :expensive_name) }
     let(:shipment) { create(:shipment_with, :shipping_method, shipping_method: shipping_method) }
 
-    let(:enterprise_fee1) { create(:enterprise_fee, enterprise: user1.enterprises.first, tax_category: product2.tax_category, calculator: Spree::Calculator::FlatRate.new(preferred_amount: 10)) }
-    let(:enterprise_fee2) { create(:enterprise_fee, enterprise: user1.enterprises.first, tax_category: product2.tax_category, calculator: Spree::Calculator::FlatRate.new(preferred_amount: 20)) }
+    let(:enterprise_fee1) { create(:enterprise_fee, enterprise: user1.enterprises.first, tax_category: product2.tax_category, calculator: Calculator::FlatRate.new(preferred_amount: 10)) }
+    let(:enterprise_fee2) { create(:enterprise_fee, enterprise: user1.enterprises.first, tax_category: product2.tax_category, calculator: Calculator::FlatRate.new(preferred_amount: 20)) }
     let(:order_cycle) { create(:simple_order_cycle, coordinator: distributor1, coordinator_fees: [enterprise_fee1, enterprise_fee2], distributors: [distributor1], variants: [product1.master]) }
 
     let!(:zone) { create(:zone_with_member) }
diff --git a/spec/features/consumer/shopping/cart_spec.rb b/spec/features/consumer/shopping/cart_spec.rb
index 194b202d26..0bc4523a24 100644
--- a/spec/features/consumer/shopping/cart_spec.rb
+++ b/spec/features/consumer/shopping/cart_spec.rb
@@ -80,7 +80,7 @@ feature "full-page cart", js: true do
     describe "admin and handling flat fees" do
       context "when there are fees" do
         let(:handling_fee) {
-          create(:enterprise_fee, calculator: Spree::Calculator::FlatRate.new(preferred_amount: 1),
+          create(:enterprise_fee, calculator: Calculator::FlatRate.new(preferred_amount: 1),
                                   enterprise: order_cycle.coordinator, fee_type: 'admin')
         }
 
diff --git a/spec/features/consumer/shopping/checkout_spec.rb b/spec/features/consumer/shopping/checkout_spec.rb
index 76983d030b..342c699a43 100644
--- a/spec/features/consumer/shopping/checkout_spec.rb
+++ b/spec/features/consumer/shopping/checkout_spec.rb
@@ -26,11 +26,11 @@ feature "As a consumer I want to check out my cart", js: true do
   end
 
   describe "with shipping and payment methods" do
-    let(:free_shipping) { create(:shipping_method, require_ship_address: true, name: "Frogs", description: "yellow", calculator: Spree::Calculator::FlatRate.new(preferred_amount: 0.00)) }
-    let(:shipping_with_fee) { create(:shipping_method, require_ship_address: false, name: "Donkeys", description: "blue", calculator: Spree::Calculator::FlatRate.new(preferred_amount: 4.56)) }
+    let(:free_shipping) { create(:shipping_method, require_ship_address: true, name: "Frogs", description: "yellow", calculator: Calculator::FlatRate.new(preferred_amount: 0.00)) }
+    let(:shipping_with_fee) { create(:shipping_method, require_ship_address: false, name: "Donkeys", description: "blue", calculator: Calculator::FlatRate.new(preferred_amount: 4.56)) }
     let(:tagged_shipping) { create(:shipping_method, require_ship_address: false, name: "Local", tag_list: "local") }
     let!(:check_without_fee) { create(:payment_method, distributors: [distributor], name: "Roger rabbit", type: "Spree::PaymentMethod::Check") }
-    let!(:check_with_fee) { create(:payment_method, distributors: [distributor], calculator: Spree::Calculator::FlatRate.new(preferred_amount: 5.67)) }
+    let!(:check_with_fee) { create(:payment_method, distributors: [distributor], calculator: Calculator::FlatRate.new(preferred_amount: 5.67)) }
     let!(:paypal) do
       Spree::Gateway::PayPalExpress.create!(name: "Paypal", environment: 'test', distributor_ids: [distributor.id]).tap do |pm|
         pm.preferred_login = 'devnull-facilitator_api1.rohanmitchell.com'
diff --git a/spec/lib/open_food_network/enterprise_fee_calculator_spec.rb b/spec/lib/open_food_network/enterprise_fee_calculator_spec.rb
index c1e361503e..2f613393f9 100644
--- a/spec/lib/open_food_network/enterprise_fee_calculator_spec.rb
+++ b/spec/lib/open_food_network/enterprise_fee_calculator_spec.rb
@@ -16,7 +16,7 @@ module OpenFoodNetwork
         describe "summing all the per-item fees for the variant in the specified hub + order cycle" do
           let(:enterprise_fee1) { create(:enterprise_fee, amount: 20) }
           let(:enterprise_fee2) { create(:enterprise_fee, amount: 3) }
-          let(:enterprise_fee3) { create(:enterprise_fee, calculator: Spree::Calculator::FlatRate.new(preferred_amount: 2)) }
+          let(:enterprise_fee3) { create(:enterprise_fee, calculator: Calculator::FlatRate.new(preferred_amount: 2)) }
 
           describe "supplier fees" do
             let!(:exchange1) {
@@ -131,7 +131,7 @@ module OpenFoodNetwork
         let(:order) { create(:order, distributor: distributor, order_cycle: order_cycle) }
         let!(:line_item) { create(:line_item, order: order, variant: product1.master) }
         let(:enterprise_fee_line_item) { create(:enterprise_fee) }
-        let(:enterprise_fee_order) { create(:enterprise_fee, calculator: Spree::Calculator::FlatRate.new(preferred_amount: 2)) }
+        let(:enterprise_fee_order) { create(:enterprise_fee, calculator: Calculator::FlatRate.new(preferred_amount: 2)) }
         let!(:exchange) { create(:exchange, order_cycle: order_cycle, sender: coordinator, receiver: distributor, incoming: false, variants: [product1.master]) }
 
         before { order.reload }
diff --git a/spec/mailers/producer_mailer_spec.rb b/spec/mailers/producer_mailer_spec.rb
index 66dd425f95..57c548f73e 100644
--- a/spec/mailers/producer_mailer_spec.rb
+++ b/spec/mailers/producer_mailer_spec.rb
@@ -7,7 +7,7 @@ describe ProducerMailer, type: :mailer do
   before { setup_email }
 
   let!(:zone) { create(:zone_with_member) }
-  let!(:tax_rate) { create(:tax_rate, included_in_price: true, calculator: Spree::Calculator::DefaultTax.new, zone: zone, amount: 0.1) }
+  let!(:tax_rate) { create(:tax_rate, included_in_price: true, calculator: Calculator::DefaultTax.new, zone: zone, amount: 0.1) }
   let!(:tax_category) { create(:tax_category, tax_rates: [tax_rate]) }
   let(:s1) { create(:supplier_enterprise) }
   let(:s2) { create(:supplier_enterprise) }
diff --git a/spec/models/enterprise_fee_spec.rb b/spec/models/enterprise_fee_spec.rb
index a422358bb8..903d22f757 100644
--- a/spec/models/enterprise_fee_spec.rb
+++ b/spec/models/enterprise_fee_spec.rb
@@ -60,17 +60,17 @@ describe EnterpriseFee do
   describe "scopes" do
     describe "finding per-item enterprise fees" do
       it "does not return fees with FlatRate, FlexiRate and PriceSack calculators" do
-        create(:enterprise_fee, calculator: Spree::Calculator::FlatRate.new)
-        create(:enterprise_fee, calculator: Spree::Calculator::FlexiRate.new)
-        create(:enterprise_fee, calculator: Spree::Calculator::PriceSack.new)
+        create(:enterprise_fee, calculator: Calculator::FlatRate.new)
+        create(:enterprise_fee, calculator: Calculator::FlexiRate.new)
+        create(:enterprise_fee, calculator: Calculator::PriceSack.new)
 
         expect(EnterpriseFee.per_item).to be_empty
       end
 
       it "returns fees with any other calculator" do
-        ef1 = create(:enterprise_fee, calculator: Spree::Calculator::DefaultTax.new)
+        ef1 = create(:enterprise_fee, calculator: Calculator::DefaultTax.new)
         ef2 = create(:enterprise_fee, calculator: Calculator::FlatPercentPerItem.new)
-        ef3 = create(:enterprise_fee, calculator: Spree::Calculator::PerItem.new)
+        ef3 = create(:enterprise_fee, calculator: Calculator::PerItem.new)
 
         expect(EnterpriseFee.per_item).to match_array [ef1, ef2, ef3]
       end
@@ -78,17 +78,17 @@ describe EnterpriseFee do
 
     describe "finding per-order enterprise fees" do
       it "returns fees with FlatRate, FlexiRate and PriceSack calculators" do
-        ef1 = create(:enterprise_fee, calculator: Spree::Calculator::FlatRate.new)
-        ef2 = create(:enterprise_fee, calculator: Spree::Calculator::FlexiRate.new)
-        ef3 = create(:enterprise_fee, calculator: Spree::Calculator::PriceSack.new)
+        ef1 = create(:enterprise_fee, calculator: Calculator::FlatRate.new)
+        ef2 = create(:enterprise_fee, calculator: Calculator::FlexiRate.new)
+        ef3 = create(:enterprise_fee, calculator: Calculator::PriceSack.new)
 
         expect(EnterpriseFee.per_order).to match_array [ef1, ef2, ef3]
       end
 
       it "does not return fees with any other calculator" do
-        ef1 = create(:enterprise_fee, calculator: Spree::Calculator::DefaultTax.new)
+        ef1 = create(:enterprise_fee, calculator: Calculator::DefaultTax.new)
         ef2 = create(:enterprise_fee, calculator: Calculator::FlatPercentPerItem.new)
-        ef3 = create(:enterprise_fee, calculator: Spree::Calculator::PerItem.new)
+        ef3 = create(:enterprise_fee, calculator: Calculator::PerItem.new)
 
         expect(EnterpriseFee.per_order).to be_empty
       end
diff --git a/spec/models/spree/calculator/flat_percent_item_total_spec.rb b/spec/models/spree/calculator/flat_percent_item_total_spec.rb
index ec4b54fc70..b0ee8f1aa0 100644
--- a/spec/models/spree/calculator/flat_percent_item_total_spec.rb
+++ b/spec/models/spree/calculator/flat_percent_item_total_spec.rb
@@ -1,7 +1,7 @@
 require 'spec_helper'
 
-describe Spree::Calculator::FlatPercentItemTotal do
-  let(:calculator) { Spree::Calculator::FlatPercentItemTotal.new }
+describe Calculator::FlatPercentItemTotal do
+  let(:calculator) { Calculator::FlatPercentItemTotal.new }
   let(:line_item) { build(:line_item, price: 10, quantity: 1) }
 
   before { allow(calculator).to receive_messages preferred_flat_percent: 10 }
diff --git a/spec/models/spree/calculator/flat_rate_spec.rb b/spec/models/spree/calculator/flat_rate_spec.rb
index 3e3bba064b..5036d6b180 100644
--- a/spec/models/spree/calculator/flat_rate_spec.rb
+++ b/spec/models/spree/calculator/flat_rate_spec.rb
@@ -1,7 +1,7 @@
 require 'spec_helper'
 
-describe Spree::Calculator::FlatRate do
-  let(:calculator) { Spree::Calculator::FlatRate.new }
+describe Calculator::FlatRate do
+  let(:calculator) { Calculator::FlatRate.new }
 
   before { allow(calculator).to receive_messages preferred_amount: 10 }
 
diff --git a/spec/models/spree/calculator/flexi_rate_spec.rb b/spec/models/spree/calculator/flexi_rate_spec.rb
index 0440e87ca8..9192aecdb5 100644
--- a/spec/models/spree/calculator/flexi_rate_spec.rb
+++ b/spec/models/spree/calculator/flexi_rate_spec.rb
@@ -1,9 +1,9 @@
 require 'spec_helper'
 
-describe Spree::Calculator::FlexiRate do
+describe Calculator::FlexiRate do
   let(:line_item) { build(:line_item, quantity: quantity) }
   let(:calculator) do
-    Spree::Calculator::FlexiRate.new(
+    Calculator::FlexiRate.new(
       preferred_first_item: 2,
       preferred_additional_item: 1,
       preferred_max_items: 3
@@ -27,7 +27,7 @@ describe Spree::Calculator::FlexiRate do
   end
 
   it "allows creation of new object with all the attributes" do
-    Spree::Calculator::FlexiRate.new(preferred_first_item: 1, preferred_additional_item: 1, preferred_max_items: 1)
+    Calculator::FlexiRate.new(preferred_first_item: 1, preferred_additional_item: 1, preferred_max_items: 1)
   end
 
   context "extends LocalizedNumber" do
diff --git a/spec/models/spree/calculator/per_item_spec.rb b/spec/models/spree/calculator/per_item_spec.rb
index 640c4b32f6..7ce41251f4 100644
--- a/spec/models/spree/calculator/per_item_spec.rb
+++ b/spec/models/spree/calculator/per_item_spec.rb
@@ -1,7 +1,7 @@
 require 'spec_helper'
 
-describe Spree::Calculator::PerItem do
-  let(:calculator) { Spree::Calculator::PerItem.new(preferred_amount: 10) }
+describe Calculator::PerItem do
+  let(:calculator) { Calculator::PerItem.new(preferred_amount: 10) }
   let(:shipping_calculable) { double(:calculable) }
   let(:line_item) { build(:line_item, quantity: 5) }
 
diff --git a/spec/models/spree/calculator/price_sack_spec.rb b/spec/models/spree/calculator/price_sack_spec.rb
index 703bea1531..83a6ae84fb 100644
--- a/spec/models/spree/calculator/price_sack_spec.rb
+++ b/spec/models/spree/calculator/price_sack_spec.rb
@@ -1,8 +1,8 @@
 require 'spec_helper'
 
-describe Spree::Calculator::PriceSack do
+describe Calculator::PriceSack do
   let(:calculator) do
-    calculator = Spree::Calculator::PriceSack.new
+    calculator = Calculator::PriceSack.new
     calculator.preferred_minimal_amount = 5
     calculator.preferred_normal_amount = 10
     calculator.preferred_discount_amount = 1
diff --git a/spec/models/spree/line_item_spec.rb b/spec/models/spree/line_item_spec.rb
index ca4a5353d9..bef32dc8d7 100644
--- a/spec/models/spree/line_item_spec.rb
+++ b/spec/models/spree/line_item_spec.rb
@@ -35,7 +35,7 @@ module Spree
       end
 
       describe "finding line items with and without tax" do
-        let(:tax_rate) { create(:tax_rate, calculator: Spree::Calculator::DefaultTax.new) }
+        let(:tax_rate) { create(:tax_rate, calculator: Calculator::DefaultTax.new) }
         let!(:adjustment1) { create(:adjustment, originator: tax_rate, label: "TR", amount: 123, included_tax: 10.00) }
 
         before do
@@ -311,7 +311,7 @@ module Spree
     describe "tax" do
       let(:li_no_tax)   { create(:line_item) }
       let(:li_tax)      { create(:line_item) }
-      let(:tax_rate)    { create(:tax_rate, calculator: Spree::Calculator::DefaultTax.new) }
+      let(:tax_rate)    { create(:tax_rate, calculator: Calculator::DefaultTax.new) }
       let!(:adjustment) { create(:adjustment, adjustable: li_tax, originator: tax_rate, label: "TR", amount: 123, included_tax: 10.00) }
 
       context "checking if a line item has tax included" do
diff --git a/spec/models/spree/order_spec.rb b/spec/models/spree/order_spec.rb
index 11ac15fa27..0c2c3d33e5 100644
--- a/spec/models/spree/order_spec.rb
+++ b/spec/models/spree/order_spec.rb
@@ -137,7 +137,7 @@ describe Spree::Order do
     let(:li) { create(:line_item, order: o) }
 
     it "returns the sum of eligible enterprise fee adjustments" do
-      ef = create(:enterprise_fee, calculator: Spree::Calculator::FlatRate.new )
+      ef = create(:enterprise_fee, calculator: Calculator::FlatRate.new )
       ef.calculator.set_preference :amount, 123.45
       a = ef.create_adjustment("adjustment", o, o, true)
 
@@ -145,7 +145,7 @@ describe Spree::Order do
     end
 
     it "does not include ineligible adjustments" do
-      ef = create(:enterprise_fee, calculator: Spree::Calculator::FlatRate.new )
+      ef = create(:enterprise_fee, calculator: Calculator::FlatRate.new )
       ef.calculator.set_preference :amount, 123.45
       a = ef.create_adjustment("adjustment", o, o, true)
 
@@ -155,7 +155,7 @@ describe Spree::Order do
     end
 
     it "does not include adjustments that do not originate from enterprise fees" do
-      sm = create(:shipping_method, calculator: Spree::Calculator::FlatRate.new )
+      sm = create(:shipping_method, calculator: Calculator::FlatRate.new )
       sm.calculator.set_preference :amount, 123.45
       sm.create_adjustment("adjustment", o, o, true)
 
@@ -163,7 +163,7 @@ describe Spree::Order do
     end
 
     it "does not include adjustments whose source is a line item" do
-      ef = create(:enterprise_fee, calculator: Spree::Calculator::PerItem.new )
+      ef = create(:enterprise_fee, calculator: Calculator::PerItem.new )
       ef.calculator.set_preference :amount, 123.45
       ef.create_adjustment("adjustment", li.order, li, true)
 
@@ -669,7 +669,7 @@ describe Spree::Order do
     end
 
     context "changing the shipping method to one without fees" do
-      let(:shipping_method) { create(:shipping_method, calculator: Spree::Calculator::FlatRate.new(preferred_amount: 0)) }
+      let(:shipping_method) { create(:shipping_method, calculator: Calculator::FlatRate.new(preferred_amount: 0)) }
 
       it "updates shipping fees" do
         order.shipments = [create(:shipment_with, :shipping_method, shipping_method: shipping_method)]
@@ -681,7 +681,7 @@ describe Spree::Order do
     end
 
     context "changing the payment method to one without fees" do
-      let(:payment_method) { create(:payment_method, calculator: Spree::Calculator::FlatRate.new(preferred_amount: 0)) }
+      let(:payment_method) { create(:payment_method, calculator: Calculator::FlatRate.new(preferred_amount: 0)) }
 
       it "removes transaction fees" do
         # Change the payment method
diff --git a/spec/models/spree/payment_spec.rb b/spec/models/spree/payment_spec.rb
index 46a493fa96..eb148a736c 100644
--- a/spec/models/spree/payment_spec.rb
+++ b/spec/models/spree/payment_spec.rb
@@ -138,7 +138,7 @@ module Spree
         let!(:payment_method) { create(:payment_method, calculator: calculator) }
 
         let!(:calculator) do
-          Spree::Calculator::FlatPercentItemTotal.new(preferred_flat_percent: 10)
+          Calculator::FlatPercentItemTotal.new(preferred_flat_percent: 10)
         end
 
         context "when order complete and inventory tracking enabled" do
@@ -159,7 +159,7 @@ module Spree
         let(:shop) { create(:enterprise) }
         let(:payment_method) { create(:stripe_payment_method, distributor_ids: [create(:distributor_enterprise).id], preferred_enterprise_id: shop.id) }
         let(:payment) { create(:payment, order: order, payment_method: payment_method, amount: order.total) }
-        let(:calculator) { Spree::Calculator::FlatPercentItemTotal.new(preferred_flat_percent: 10) }
+        let(:calculator) { Calculator::FlatPercentItemTotal.new(preferred_flat_percent: 10) }
 
         before do
           payment_method.calculator = calculator
diff --git a/spec/models/spree/tax_rate_spec.rb b/spec/models/spree/tax_rate_spec.rb
index 888b25c890..61938c5d0f 100644
--- a/spec/models/spree/tax_rate_spec.rb
+++ b/spec/models/spree/tax_rate_spec.rb
@@ -33,7 +33,7 @@ module Spree
     end
 
     describe "ensuring that tax rate is marked as tax included_in_price" do
-      let(:tax_rate) { create(:tax_rate, included_in_price: false, calculator: Spree::Calculator::DefaultTax.new) }
+      let(:tax_rate) { create(:tax_rate, included_in_price: false, calculator: Calculator::DefaultTax.new) }
 
       it "sets included_in_price to true" do
         tax_rate.send(:with_tax_included_in_price) do
diff --git a/spec/models/tag_rule/discount_order_spec.rb b/spec/models/tag_rule/discount_order_spec.rb
index 2a1260f7e3..831f2faf01 100644
--- a/spec/models/tag_rule/discount_order_spec.rb
+++ b/spec/models/tag_rule/discount_order_spec.rb
@@ -73,7 +73,7 @@ describe TagRule::DiscountOrder, type: :model do
     end
 
     context "when shipping charges apply" do
-      let!(:shipping_method) { create(:shipping_method, calculator: Spree::Calculator::FlatRate.new( preferred_amount: 25.00 ) ) }
+      let!(:shipping_method) { create(:shipping_method, calculator: Calculator::FlatRate.new( preferred_amount: 25.00 ) ) }
       before do
         shipping_method.create_adjustment("Shipping", order, order, true)
       end
diff --git a/spec/requests/checkout/failed_checkout_spec.rb b/spec/requests/checkout/failed_checkout_spec.rb
index f45efe3951..41062d97d0 100644
--- a/spec/requests/checkout/failed_checkout_spec.rb
+++ b/spec/requests/checkout/failed_checkout_spec.rb
@@ -32,7 +32,7 @@ describe "checking out an order that initially fails", type: :request do
   end
 
   context "when shipping and payment fees apply" do
-    let(:calculator) { Spree::Calculator::FlatPercentItemTotal.new(preferred_flat_percent: 10) }
+    let(:calculator) { Calculator::FlatPercentItemTotal.new(preferred_flat_percent: 10) }
 
     before do
       payment_method.calculator = calculator.dup
diff --git a/spec/requests/checkout/paypal_spec.rb b/spec/requests/checkout/paypal_spec.rb
index 96c1baf4e9..e309d0ea5d 100644
--- a/spec/requests/checkout/paypal_spec.rb
+++ b/spec/requests/checkout/paypal_spec.rb
@@ -50,7 +50,7 @@ describe "checking out an order with a paypal express payment method", type: :re
   end
 
   context "with a flat percent calculator" do
-    let(:calculator) { Spree::Calculator::FlatPercentItemTotal.new(preferred_flat_percent: 10) }
+    let(:calculator) { Calculator::FlatPercentItemTotal.new(preferred_flat_percent: 10) }
 
     before do
       payment_method.calculator = calculator
diff --git a/spec/requests/checkout/stripe_connect_spec.rb b/spec/requests/checkout/stripe_connect_spec.rb
index 5c1561c13c..000b2250a8 100644
--- a/spec/requests/checkout/stripe_connect_spec.rb
+++ b/spec/requests/checkout/stripe_connect_spec.rb
@@ -10,7 +10,7 @@ describe "checking out an order with a Stripe Connect payment method", type: :re
   let!(:shipping_method) do
     create(
       :shipping_method,
-      calculator: Spree::Calculator::FlatRate.new(preferred_amount: 0),
+      calculator: Calculator::FlatRate.new(preferred_amount: 0),
       distributors: [enterprise]
     )
   end
diff --git a/spec/requests/checkout/stripe_sca_spec.rb b/spec/requests/checkout/stripe_sca_spec.rb
index 5018ad321c..d2734f66d4 100644
--- a/spec/requests/checkout/stripe_sca_spec.rb
+++ b/spec/requests/checkout/stripe_sca_spec.rb
@@ -12,7 +12,7 @@ describe "checking out an order with a Stripe SCA payment method", type: :reques
   let!(:shipping_method) do
     create(
       :shipping_method,
-      calculator: Spree::Calculator::FlatRate.new(preferred_amount: 0),
+      calculator: Calculator::FlatRate.new(preferred_amount: 0),
       distributors: [enterprise]
     )
   end
diff --git a/spec/services/tax_rate_finder_spec.rb b/spec/services/tax_rate_finder_spec.rb
index 3f5daadfcf..6881d66ebf 100644
--- a/spec/services/tax_rate_finder_spec.rb
+++ b/spec/services/tax_rate_finder_spec.rb
@@ -66,7 +66,7 @@ describe TaxRateFinder do
       create(
         :tax_rate,
         amount: amount,
-        calculator: Spree::Calculator::DefaultTax.new,
+        calculator: Calculator::DefaultTax.new,
         zone: zone
       )
     end