@langgraph-js/bundler NPM

LangGraph Bundler

A build tool for LangGraph.js applications that packages your graph configurations into deployable modules.

Overview

LangGraph Bundler simplifies the process of bundling and deploying LangGraph.js applications. It reads your langgraph.json configuration and builds optimized modules for all your defined graphs and authentication handlers.

Features

Zero Configuration: Automatically reads your langgraph.json file
Multiple Graph Support: Builds all graphs defined in your configuration
ES Module Output: Generates optimized ES modules for modern environments
Development Server: Includes a development server for testing
Hono Server Support: Generates a Hono server entrypoint for edge deployment
Seamless Integration: Works with the LangGraph.js ecosystem
Multi-Runtime Support: Supports Bun, Deno, and Node.js environments

Usage

Installation

npm install @langgraph-js/bundler @langgraph-js/api --save-dev

Configuration

Create a langgraph.json file in your project root with the following structure:

{
  "node_version": "20",
  "dependencies": ["."],
  "graphs": {
    "agent": "./src/agents/my-agent.ts:graph"
  },
  "env": ".env",
  "auth": {
    "path": "./src/auth.ts:auth"
  },
  "dist": "./dist"
}

Building Your Project

Run the bundler:

npx @langgraph-js/bundler

This will:

Read your langgraph.json configuration
Build all defined graphs and authentication handlers
Output the bundled files to your specified dist directory
Generate a development server and Hono server entrypoint

Configuration Options

node_version: The Node.js version to target
dependencies: Array of dependency directories
graphs: Object mapping graph names to file paths with export names
env: Path to environment file
auth: Authentication configuration
dist: Output directory path (defaults to "./dist")

Development

Development Server

You can start the development server using the langgraph-dev command:

npx langgraph-dev

The development server automatically detects your runtime environment (Bun or Node.js) and starts the appropriate server configuration.

Runtime Behavior

Bun: Uses bunx --bun langgraph-dev
Node.js: Uses npx langgraph-dev

Manual Server Start

You can also start the bundled development server manually:

node dist/start.js

Deployment Options

Edge Deployment with Hono

The bundler generates an entrypoint.js file that can be used to deploy your LangGraph application to edge environments like Cloudflare Workers or Deno Deploy:

// Example usage with Cloudflare Workers
import entrypoint from './dist/entrypoint.js';

export default entrypoint;

Integration with LangGraph.js

This bundler is designed to work seamlessly with other LangGraph.js tools and libraries, allowing you to easily deploy your graphs to production environments.