Do I need Microsoft.NETCore.Platforms and Microsoft.NETCore.Runtime?

Question

In a new ASP.NET Core RC2 class library, I have the following project.json file, where I have tried to follow the docs on How to trim your package dependencies.

{
  "dependencies": {
    "Microsoft.AspNetCore.Mvc.Abstractions": "1.0.0-rc2-final",
    "Microsoft.AspNetCore.Mvc.Core": "1.0.0-rc2-final",
    "Microsoft.Extensions.Caching.Abstractions": "1.0.0-rc2-final",
    "Newtonsoft.Json": "8.0.3"
  },

  "frameworks": {
    "netstandard1.5": {
      "dependencies": {
        "Microsoft.NETCore.Platforms": "1.0.1-rc2-24027",
        "Microsoft.NETCore.Runtime": "1.0.2-rc2-24027",
        "System.Xml.XDocument": "4.0.11-rc2-24027"
      },
      "imports": "dnxcore50"
    },
    "net461": {
      "frameworkAssemblies": {
        "System.ServiceModel": "",
        "System.Xml": "",
        "System.Xml.Linq": ""
      }
    }
  }
}

When I have tried removing Microsoft.NETCore.Platforms and Microsoft.NETCore.Runtime, everything still works. This is probably because the Microsoft dependencies also specify these. What are these dependencies for and should I be explicit and keep them?

Answer 1

What purpose do the packages have:

• Microsoft.NETCore.Platforms is essentially only a json files which specifies the runtime identifiers (RIDs). These Ids (e.g. osx.10.10-x64 or win7-x86) are used when platform specific code needs to be deployed (e.g. a special compiled CoreCLR or platform specific compression or crypto library). It forms a kind of tree which allows more generic platform patterns (like linux which is later the parent for e.g. rhel which again is the parent for a specific supported version rhel-7.1-x64). So When someone builds a NuGet, you can add an artifiact like an assembly which is deployed on all linux machines (e.g. doing P/Invoke against the standard linux apis) or a specific linux distribution (e.g. using a special RedHat feature).

• Microsoft.NETCore.Runtime is a trickier story. It is used to lookup the right runtime for your platform.

Should you keep them: Since you do not use them directly, adding these dependencies explicitly does not bring any benefit to my understanding.