This article states that:
The existing DI (angular1) has some problem though:
Built into the framework - Angular 1’s DI is baked right into the framework. There’s no way for us to use it decoupled as a standalone system.
How can I use angular2 DI as a standalone system? It's not published as a separate package as I understand.

export * from '@angular/core/src/di'in theindex.tssource file. probably that's how it should be used. I'll try and post an answer