Background Services

IHostedService

public class EmailSenderService : IHostedService
{
    public Task StartAsync(CancellationToken cancellationToken)
    {
        // Start background work
        return Task.CompletedTask;
    }

    public Task StopAsync(CancellationToken cancellationToken)
    {
        // Stop background work
        return Task.CompletedTask;
    }
}

builder.Services.AddHostedService<EmailSenderService>();

BackgroundService

public class DataCleanupService : BackgroundService
{
    protected override async Task ExecuteAsync(CancellationToken stoppingToken)
    {
        while (!stoppingToken.IsCancellationRequested)
        {
            // Do work
            await Task.Delay(TimeSpan.FromHours(1), stoppingToken);
        }
    }
}

Channels (Producer-Consumer)

public class QueueService
{
    private readonly Channel<string> _channel = Channel.CreateUnbounded<string>();

    public async Task EnqueueAsync(string item)
    {
        await _channel.Writer.WriteAsync(item);
    }

    public IAsyncEnumerable<string> DequeueAllAsync(CancellationToken ct)
    {
        return _channel.Reader.ReadAllAsync(ct);
    }
}