Finding myself in the need of a webshop, I decided to try to deploy Spree to Heroku. It wasn’t too hard, but it did take a few tricks to get Spree running on a server that doesn’t allow you to write to the file system.
I can’t say I have too much hands-on experience with Spree yet, but it seems to be have borrowed its extension concept from Radiant CMS, which happens to be one of my areas of expertise. So I put together an extension for Spree that will easily allow you to deploy the e-commerce system to Heroku.
Just follow the instructions in the README on Github.