The .NET SDK is available from the NuGet gallery and is written in .NET Standard, so it can be used in both .NET Framework, .NET Core, and .NET 5. The package is called NStack.SDK, you can install it by searching for it through the Visual Studio Package Manager or by running the following command in the Package Manager Console

Install-Package NStack.SDK

Or if you're using the dotnet CLI, run the following command:

dotnet add package NStack.SDK

DI setup

The SDK is built with DI support in mind and can be quickly set up in your startup.cs file in ConfigureServices:

services.AddSingleton<NStackConfiguration>(r => new NStackConfiguration
{
    ApiKey = "MyApiKey",
    ApplicationId = "MyApplicationId",
    BaseUrl = "MyBaseUrl"
});
services.AddTransient<INStackRepository, NStackRepository>();
services.AddTransient<INStackLocalizeService, NStackLocalizeService>();
services.AddTransient<INStackTermsService, NStackTermsService>();

Best practice is to not hard code the configuration values but to fetch them from your application settings.