There are 4 sets of Contact APIs in Sitecore xDB:

• ContactRepository
• ContactManager
• SharedSessionStateManager
• Tracker.Current.Contact

With the release of 8.2, out-of-the-box Sitecore now uses IServiceProvider — ASP.NET’s own dependency injection abstraction, as well as its default implementation. If you haven’t yet, go read Kam’s article “Dependency Injection in Sitecore…

On Sitecore 8.1, when rebuilding the Reporting database, the following error occurs and halts the rebuild process:

Exception when storing an aggregation result into reporting database.
Item…