NinjectDependenciesProvider.cs

public abstract class NinjectDependenciesProvider
{
    protected abstract IEnumerable<INinjectModule> GetPlatformSpecificModules();
        
    protected abstract IEnumerable<INinjectModule> GetPortableNinjectModules();

    public IEnumerable<INinjectModule> GetNinjectModules()
    {
        foreach (var portableModule in GetPortableNinjectModules())
        {
            yield return portableModule;
        }
        
        foreach (var platformModule in GetPlatformSpecificModules())
        {
            yield return platformModule;
        }
    }
}