EF7: DBContext configuration on ASP.NET 5 Web-API

The code should be the same as you linked in the sample app. You register the context in Startup.cs, within ConfigureServices method using the following code:

public void ConfigureServices(IServiceCollection services)
{
    // Add EF services to the services container.
    services
        .AddEntityFramework(Configuration)
        .AddSqlServer()
        .AddDbContext<MyDbContext>(options =>
         {
             options.UseSqlServer(Configuration.Get("Data:DefaultConnection:ConnectionString"));
         });
}

Then your MyDbContext will be available for dependency injection, and in your controllers you can do

public MyController(MyDbContext context)
{
   ...
}

That's it