PLEASE do not apply if you are not a Ruby/Rails developer with experience of writing Spreecommerce extensions. The bulk of the work will require knowledge of Spree's products, variants, product properties and option types.
This is a two phase project.
I have a custom written products database application - built using Ruby on Rails. The products database publishes its list of products as an series of XML pages (with authentication) - the format was designed to be as close as possible (with some inevitable differences) to the Spree data model.
Phase one of the project is to write an importer - that takes this XML product data and imports it into a Spreecommerce site. This should be implemented as a rake task within a Spree extension - that communicates with the product database using ActiveResource. It should take the list of products and variants from the XML feed and create or update the relevant entries within Spree's products and variants tables.
Phase two of the project is to enhance the importer - there is a version of the products database that publishes various custom product properties and product option types, in addition to the basic product data. These properties and options need to be imported and updated alongside the normal data.
So to recap you will need to create a Spree extension that connects to my system over ActiveResource and then creates/updates products, variants, properties and options within the Spree site.
If all goes well with this then there will also be numerous more Spree customisations to come (especially theming).