This document summarizes the key technical differences between Odoo versions 7 and 10. It describes changes to the API, removal of the pool object, changes to file names and XML tags, removal of string references in XPath expressions, introduction of the env notion, changes to field declaration and default value setting, and changes to JavaScript usage with the introduction of Backbone.js in version 9. Some examples of new API decorators and differences in API parameters are also provided.