Hi, I’m so sorry for replying after months, but I haven’t looked at Medium for a while, I hope that this comment will help you or any reader out there.

You’re right, the difference is: is Core the right place for those services? In practice, there’s no difference, the app works exactly the same. In reality, I could have some services which relate to a SharedComponent (ex. ToolbarComponent and ToolbarService, GridComponent and GridService) and I want to keep them in the same folder.

Also, this is made easier by the new “providedIn” metadata added in the last versions of Angular: in practice, I don’t use forRoot anymore if I have no config to pass to the module :)