Program.cs

using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Hosting;
using Microsoft.Extensions.Logging;
using Microsoft.Extensions.Options;
using Polly;
using Polly.Registry;
using Polly.Retry;
using Vultar;

var builder = Host.CreateApplicationBuilder(args);

builder.Services.AddOptions<VultarSettings>()
    .BindConfiguration(VultarSettings.SectionName)
    .ValidateDataAnnotations()
    .ValidateOnStart();

builder.Services.AddResiliencePipeline("default", (pipeline, context) =>
{
    var options = context.ServiceProvider.GetRequiredService<IOptions<VultarSettings>>().Value;
    var logger = context.ServiceProvider.GetRequiredService<ILogger<Worker>>();

    pipeline.AddRetry(new RetryStrategyOptions
    {
        MaxRetryAttempts = options.MaxRetryAttempts,
        Delay = options.RetryDelay,
        BackoffType = DelayBackoffType.Exponential,
        ShouldHandle = new PredicateBuilder().Handle<Exception>(),
        OnRetry = args =>
        {
            logger.Retrying(args.AttemptNumber, args.RetryDelay);
            return ValueTask.CompletedTask;
        }
    });
});

builder.Services.AddSingleton(sp =>
    sp.GetRequiredService<ResiliencePipelineProvider<string>>().GetPipeline("default"));

builder.Services.Configure<HostOptions>(options =>
{
    var settings = builder.Configuration.GetSection(VultarSettings.SectionName).Get<VultarSettings>();
    options.ShutdownTimeout = settings?.ShutdownTimeout ?? TimeSpan.FromSeconds(30);
    options.BackgroundServiceExceptionBehavior = BackgroundServiceExceptionBehavior.StopHost;
});

builder.Services.AddHostedService<Worker>();

var host = builder.Build();
await host.RunAsync();