Define an event:

import { event } from "@trigger.dev/sdk";
import { z } from "zod";

export const orderCreated = event({
  id: "order.created",
  schema: z.object({
    orderId: z.string(),
    amount: z.number(),
    customerId: z.string(),
  }),
});

Subscribe tasks:

import { task } from "@trigger.dev/sdk";
import { orderCreated } from "./events";

export const sendReceipt = task({
  id: "send-receipt",
  on: orderCreated,
  run: async (payload) => {
    // payload is fully typed from the Zod schema
    await sendEmail(payload.customerId, payload.orderId);
  },
});

Publish:

await orderCreated.publish({
  orderId: "order-123",
  amount: 500,
  customerId: "cust-1",
});

One event, N subscribers. Each gets its own durable run with retries, logging, and tracing.

• Fan-out — One event triggers N tasks automatically
• Dead letter queue — Failed events go to DLQ with dashboard retry/discard
• Event replay — Re-publish historical events from a time range
• Content-based filtering — filter: { amount: [{ $gte: 1000 }] }
• Ordering guarantees — Sequential processing per key with orderingKey
• Publish and wait — Scatter-gather with publishAndWait()
• Rate limiting — Per-event, Redis-backed sliding window
• Consumer groups — Kafka-style load balancing with consumerGroup
• Wildcard patterns — events.match("order.*") for event families
• Schema validation — Zod, Valibot, ArkType — validated at publish time
• Full persistence — ClickHouse event log with materialized analytics views
• Dashboard UI — Events list, event detail with charts, DLQ management

This is a fork of Trigger.dev (Apache 2.0). All the existing Trigger.dev features — durable execution, retries, queues, concurrency, realtime, schedules — are still here. Fanout.sh adds the event system on top.

For Trigger.dev docs and setup, see trigger.dev/docs.

Giovanni Borgogno

Apache 2.0 — see LICENSE.

Everything below is the original Trigger.dev README. Fanout.sh is a fork — all Trigger.dev features still work.

Trigger.dev is the open-source platform for building AI workflows in TypeScript. Long-running tasks with retries, queues, observability, and elastic scaling.

• JavaScript and TypeScript SDK - Build background tasks using familiar programming models
• Long-running tasks - Handle resource-heavy tasks without timeouts
• Durable cron schedules - Create and attach recurring schedules of up to a year
• Trigger.dev Realtime - Trigger, subscribe to, and get real-time updates for runs, with LLM streaming support
• Build extensions - Hook directly into the build system and customize the build process
• React hooks - Interact with the Trigger.dev API on your frontend
• Batch triggering - Initiate multiple runs of a task with custom payloads
• Concurrency & queues - Set concurrency rules to manage task execution
• Automatic retries - Automatic retry on uncaught errors
• Checkpointing - Durable tasks via checkpointing
• Observability & monitoring - Full tracing and logs for every run

For full docs, see trigger.dev/docs.

• Docker guide
• Kubernetes guide

To setup and develop locally, follow the development guide.