core/app/models/spree/calculator/shipping/flat_rate.rb
require_dependency 'spree/shipping_calculator'
module Spree
module Calculator::Shipping
class FlatRate < ShippingCalculator
preference :amount, :decimal, default: 0
preference :currency, :string, default: -> { Spree::Store.default.default_currency }
def self.description
Spree.t(:shipping_flat_rate_per_order)
end
def compute_package(_package)
preferred_amount
end
end
end
end