Get inspired
You could build anything with Goaddon. Feel free to read through our project ideas. Some could be usefull for your ecommerce company, others could be offered to ecommerce companies by you as a service provider.
What do you get from Goaddon?
By subscribing to the Goexplore addon you get a website that online shops can use to sign up.
By subscribing to the Gofetch addon you enable the merchants to import their orders and products into your database.
If you install the explorer-at-goexplore repository, your website even get a products page where you can summarize reviews for each product.
What do you need to build on top of it?
You would need to integrate the website with an application of your own, one that can manage background processes. That application should recurringly go through the orders in your database and select orders due to have a review email sent.
Additionally you need to build the functionality that aggregates and displays the reviews.
What else you need depends on what the product reviews should be used for.
How fast can you build it?
Building the algotithm to identify orders ready for the review email could take a year, since the selection process is quite complicated.