Send emails with .NET

using Resend;

builder.Services.AddOptions();
builder.Services.AddHttpClient<ResendClient>();
builder.Services.Configure<ResendClientOptions>( o =>
{
    o.ApiToken = Environment.GetEnvironmentVariable( "RESEND_APITOKEN" )!;
} );
builder.Services.AddTransient<IResend, ResendClient>();

using Resend;

public class FeatureImplementation
{
    private readonly IResend _resend;

    public FeatureImplementation( IResend resend )
    {
        _resend = resend;
    }

    public Task Execute()
    {
        var message = new EmailMessage();
        message.From = "Acme <onboarding@resend.dev>";
        message.To.Add( "delivered@resend.dev" );
        message.Subject = "hello world";
        message.HtmlBody = "<strong>it works!</strong>";

        await _resend.EmailSendAsync( message );
    }
}