Automatic autoloading will only work for Solidus versions minor than 3.2. Take a look at monkey patches for the current recommended approach.

Solidus autoloads any file in the /app directory that has the suffix _decorator.rb, just like any other Rails models or controllers. This allows you to monkey patch Solidus functionality for your store.

For example, if you want to add a method to the Spree::Order model, you could create /app/models/mystore/order_decorator.rb with the following contents:

      module MyStore::OrderDecorator
  def total
    super + BigDecimal(10.0)

  Spree::Order.prepend self


This creates a new module called MyStore::OrderDecorator that prepends its methods early in the method lookup chain. So, for method calls on Spree::Order objects, the decorator's total method would override the original total method.

With the code above live on your server, every call to will return the original total plus $10 (or whatever your currency is).

Using class-level methods in decorators

You'll need to define a special method in order to access some class-level methods

      module MyStore::ProductDecorator

  # This is the place to define custom associations, delegations, scopes and
  # other ActiveRecord stuff
  def self.prepended(base)
    base.has_many :comments, dependent: :destroy
    base.scope    :sellable, -> { base.where(...).order(...) }
    base.delegate :something, to: :something


  Spree::Product.prepend self


In this example, a decorator has been used to extend the functionality of Spree::Product. The decorator includes an ActiveRecord association, scope, and delegation.

Decorators and Solidus upgrades

Decorators can complicate your Solidus upgrades. If you depend on decorators, ensure that you test them before upgrading in a production environment. Note that Solidus's core classes may change with each release.


Solidus is an open source platform supported by the community. We encourage everyone using Solidus to contribute back to the documentation and the code.

If you’re interested in contributing to the docs, get started with the contributing guidelines. If you see something that needs fixing and can’t do it yourself, please send us an email.