JavaScript SDK

The official JavaScript/TypeScript SDK for Ironflow, organized as a monorepo of specialized packages published under the @ironflow organization on npm. All packages are public and install without authentication.

For building Ironflow and the SDKs from source, see the Local Development guide.

Packages

Package	Use Case	Environment
@ironflow/browser	Real-time subscriptions, workflow triggers, event emission	Browser
@ironflow/node	Workers, serve handlers, step execution	Node.js
@ironflow/core	Shared types, schemas, utilities	Both
@ironflow/langgraph	LangGraph checkpoint saver — durable agent state backed by entity streams	Node.js

Which Package Should I Use?

Building a Web Application

Use @ironflow/browser for:

• Subscribing to real-time events
• Triggering workflows from the frontend
• Monitoring run status
• Emitting events

npm install @ironflow/browser

import { ironflow } from '@ironflow/browser';

ironflow.configure({ serverUrl: 'https://ironflow.example.com' });

// Subscribe to events
const sub = await ironflow.subscribe('events:order.*', {
  onEvent: (event) => console.log('Order:', event),
});

// Invoke a function
const run = await ironflow.invoke('process-order', {
  data: { orderId: '123' },
});

Building a Backend Service

Use @ironflow/node for:

• Defining functions
• Creating serverless handlers (push mode)
• Running long-lived workers (pull mode)
• Executing durable steps

npm install @ironflow/node

Push Mode (Serverless):

import { serve, ironflow } from '@ironflow/node';

const processOrder = ironflow.createFunction(
  { id: 'process-order', triggers: [{ event: 'order.placed' }] },
  async ({ event, step }) => {
    const result = await step.run('process', async () => {
      return { processed: true };
    });
    return result;
  }
);

// Next.js App Router
export const POST = serve({ functions: [processOrder] });

Pull Mode (Worker):

import { createWorker, ironflow } from '@ironflow/node';

const worker = createWorker({
  serverUrl: 'http://localhost:9123',
  functions: [processOrder],
  maxConcurrentJobs: 10,
});

await worker.start();

Using Types and Utilities

@ironflow/core is automatically included as a dependency of both browser and node packages. You typically don’t need to install it directly, but you can import types and utilities from it:

import type { Run, IronflowEvent, FunctionConfig } from '@ironflow/core';
import { RunStatusSchema, isRetryable } from '@ironflow/core';

Execution Modes

The SDK supports two execution modes:

Mode	Description	Best For
Push	Ironflow sends HTTP requests to your endpoint	Serverless (Vercel, Lambda), short tasks
Pull	Your worker connects via gRPC and pulls jobs	Long-running tasks, no timeout limits

Both modes use the same function definition syntax. See Execution Modes for details.

Quick Links

• Browser Package Reference - Full API for browser client
• Node Package Reference - Workers, serve handlers, step primitives
• Core Package Reference - Types, schemas, utilities
• Step Primitives Guide - run, sleep, waitForEvent, parallel, map
• Getting Started - Emit events, projections, and time-travel in 5 minutes

Requirements

• Node.js 20+ for @ironflow/node
• Modern browsers (Chrome 80+, Firefox 75+, Safari 13.1+, Edge 80+) for @ironflow/browser