ZeroAlloc.Scheduling.Dashboard.Blazor

ZeroAlloc.Scheduling

ZeroAlloc.Scheduling is a source-generated background job scheduler for .NET 8, 9 and 10. Decorate any class with [Job] and the source generator wires up the executor, DI registration, and recurring startup automatically — no reflection, no convention scanning at runtime.

Install

The source generator is bundled into the main package — a single PackageReference is all you need:

dotnet add package ZeroAlloc.Scheduling
dotnet add package ZeroAlloc.Scheduling.InMemory   # or EfCore / Orm / Redis

The standalone ZeroAlloc.Scheduling.Generator package is still published for backwards compatibility with existing direct PackageReferences, but new consumers should reference only ZeroAlloc.Scheduling.

Example

using System.Text.Json.Serialization;
using Microsoft.Extensions.DependencyInjection;
using ZeroAlloc.Scheduling;
using ZeroAlloc.Scheduling.InMemory;
using ZeroAlloc.Serialisation;

// 1. Define jobs — the generator picks them up automatically.
//    [ZeroAllocSerializable] plus a JsonSerializerContext give each job an AOT-safe serializer,
//    because the store persists every job as bytes.
[Job(Every = Every.Hour)]
[ZeroAllocSerializable(SerializationFormat.SystemTextJson)]
public sealed class CleanupExpiredSessionsJob : IJob
{
    public ValueTask ExecuteAsync(JobContext ctx, CancellationToken ct)
        => ctx.Services.GetRequiredService<ISessionRepository>().DeleteExpiredAsync(ct);
}

[Job]
[ZeroAllocSerializable(SerializationFormat.SystemTextJson)]
public sealed record SendOrderConfirmationJob(int OrderId) : IJob
{
    public ValueTask ExecuteAsync(JobContext ctx, CancellationToken ct)
        => ctx.Services.GetRequiredService<IOrderMailer>().SendConfirmationAsync(OrderId, ct);
}

[JsonSerializable(typeof(CleanupExpiredSessionsJob))]
internal sealed partial class CleanupExpiredSessionsJobJsonContext : JsonSerializerContext;

[JsonSerializable(typeof(SendOrderConfirmationJob))]
internal sealed partial class SendOrderConfirmationJobJsonContext : JsonSerializerContext;

// 2. Register — the generated Add...Job() methods wire each executor, and the recurring startup
//    for CleanupExpiredSessionsJob. AddSerializerDispatcher() is generated by ZeroAlloc.Serialisation,
//    which ZeroAlloc.Scheduling brings in; see docs/migrating-to-v2.md.
services.AddSerializerDispatcher();
services.AddScheduling()
        .WithInMemoryStore()
        .AddCleanupExpiredSessionsJob()
        .AddSendOrderConfirmationJob();

// 3. Enqueue a one-off job from application code
public class OrderService(IScheduler scheduler)
{
    public async Task CompleteOrderAsync(Order order, CancellationToken ct)
    {
        await ProcessAsync(order, ct);
        await scheduler.EnqueueAsync(new SendOrderConfirmationJob(order.Id), ct);
    }
}

Performance

Head-to-head vs Coravel 6.0.2 (de-facto in-process scheduler) and a hand-rolled BackgroundService + Timer baseline. BenchmarkDotNet 0.15.8, .NET 10.0.13, measured 2026-10-15. Allocations are exact. Speed is shown as same-run ratios, because the benchmark host is a shared VM; absolute timings are not published.

Honest reading: Coravel's Schedule() is a runtime call that allocates a queue entry; 100 calls allocate 76,320 B and take 15.36× as long as one in the same run. ZA.Scheduling's [Job] registration happens at compile time via source generation — no equivalent runtime cost. For dispatch overhead, ZA matches a hand-written Timer: BenchmarkDotNet cannot tell either from an empty method. The value of the abstraction is [Job] itself (declarative retries / cron / store-backed persistence), not raw dispatch speed.

Full methodology + design analysis: docs/performance.md.

Features

• Source generator — [Job] on a class emits a typed executor, DI extension method, and optional recurring startup (IHostedService)
• Recurring jobs — [Job(Cron = "0 * * * *")] or [Job(Every = Every.Hour)] — scheduled via Cronos at startup
• Retry with backoff — exponential retry up to MaxAttempts (per-job or global); dead-letters after exhaustion
• Multiple backends — InMemory (dev/test), EF Core (SQL Server / PostgreSQL / SQLite), ZeroAlloc.ORM, Redis
• Dashboard — embedded HTML/JS dashboard via app.MapJobsDashboard("/jobs")
• Blazor component — <JobsDashboard> Razor component for integration into Blazor apps
• Mediator bridge — [Job] + IRequest<Unit> auto-registers MediatorJobTypeExecutor<T>, routing execution through ZeroAlloc.Mediator pipeline behaviors
• Native AOT compatible — no reflection at runtime; all dispatch resolved at compile time

Dashboard

An embedded HTML/JS dashboard — summary cards for each job state, a live-refreshing table with per-row requeue / delete actions, and fully responsive down to mobile widths.

app.MapJobsDashboard("/jobs");

// Optional: protect with auth
app.MapJobsDashboard("/jobs").RequireAuthorization("AdminPolicy");

Tablet (768 × 1024) and mobile (375 × 812) captures live in docs/screenshots/.

See Dashboard for the full endpoint reference and the Blazor component.

Packages

Documentation

License

MIT