JobMaster

Distributed job orchestration engine for .NET. Built for horizontal scale, designed for resilience.

📖 docs.jobmaster.hugoj0s3.dev

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Quick Start

Standalone is the simplest way to run JobMaster. A single database connection handles coordination, job storage, and the transport layer — no additional brokers required.

Register in Program.cs

builder.Services.AddJobMasterCluster(config =>
{
    config.UseStandaloneCluster()
          .ClusterId("Local-Cluster-01")
          .UsePostgres("Host=localhost;Database=jobmaster_db;Username=postgres;Password=pwd")
          .AddWorker();
});

var app = builder.Build();

await app.Services.StartJobMasterRuntimeAsync();

Implement a Job Handler

public sealed class HelloJobHandler : IJobHandler
{
    public async Task HandleAsync(JobContext job)
    {
        var name = job.MsgData.TryGetStringValue("Name") ?? "World";
        Console.WriteLine($"Hello {name}");
        await Task.CompletedTask;
    }
}

Handlers are resolved from the .NET DI container — inject your services (repositories, HTTP clients, etc.) directly into the constructor.

Schedule a Job

IJobMasterScheduler is registered automatically. Inject it anywhere in your application.

app.MapPost("/schedule-job", async (IJobMasterScheduler jobScheduler) =>
{
    var msg = WriteableMessageData.New().SetStringValue("Name", "John Doe");

    await jobScheduler.OnceNowAsync<HelloJobHandler>(msg);

    return Results.Accepted();
}).WithOpenApi();

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Core Concepts

JobMaster separates responsibilities into three layers:

• Cluster Database (Master) — source of truth. Stores jobs, coordinates agents, and persists configuration.
• Agents (Transport Layer) — ephemeral, high-speed buffers for in-flight jobs. Supports PostgreSQL, MySQL, SQL Server, and NATS JetStream.
• Workers (Execution Layer) — claim and execute jobs using atomic locks. Scale horizontally with zero downtime.

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Recurring Schedules

JobMaster supports recurrence expressions using the NaturalCron library.

// Fluent builder
var expression = NaturalCronBuilder.Every(1).Minutes().Build();
await jobScheduler.RecurringAsync<HelloJobHandler>(expression);

// Expression string
await jobScheduler.RecurringAsync<HelloJobHandler>(NaturalCronExprCompiler.TypeId, "every 1 minutes");

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Dashboard & API

JobMaster ships a browser-based dashboard and a REST API for monitoring clusters, jobs, workers, buckets, and agent connections in real time.

dotnet add package JobMaster.Api
dotnet add package JobMaster.Dashboard

Both can run in a completely separate process from your workers — all they need is access to the master database.

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Documentation

Full documentation is available at docs.jobmaster.hugoj0s3.dev:

• Getting Started
• [Scheduling] (https://docs.jobmaster.hugoj0s3.dev/docs/scheduling/one-off-scheduling)
• Architecture Overview

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Roadmap

See docs.jobmaster.hugoj0s3.dev/docs/roadmap.