FastAPI + LangGraph Workflow Orchestration Template

A starter template for building AI-driven workflow orchestration systems using FastAPI and LangGraph. This project provides a modular foundation with state management, persistence, and REST APIs so you can quickly prototype and extend your own workflows.

Features

• FastAPI-based REST API endpoints for workflow management
• LangGraph integration for AI workflow orchestration
• Modular, extensible workflow architecture
• Built-in state management and checkpointing
• PostgreSQL-backed workflow persistence
• Support for workflow interrupts and continuations
• Non-blocking concurrent workflow execution using ThreadPoolExecutor

Prerequisites

• Python 3.11 or higher
• PostgreSQL database

Installation

1. Clone the repository:

git clone <repository-url>
cd agentic-template

2. Install dependencies:

pip install -r requirements.txt

3. Set up environment variables:

• Copy the example environment file:

cp .env.example .env

• Update values in .env to match your local setup (database URL, host, port, etc.).

Usage

1. Start the server:

• Default port (8000):

uvicorn app:app --reload

• Custom port:

uvicorn app:app --reload --port 8080

• Using environment variables (defined in .env):

uvicorn app:app --reload --port $PORT --host $HOST

2. Access the API at:

http://localhost:<port>

API Endpoints

• GET / — API information and available endpoints
• POST /workflows/{workflow_name} — Start a new workflow
• POST /workflows/{workflow_name}/{thread_id} — Continue an existing workflow
• GET /workflows/{workflow_name}/{thread_id} — Get workflow state

Notes

• This repository is a template intended for customization. Replace example workflows, models, and configuration with your own domain logic.
• Consider adding authentication, rate limiting, and observability for production deployments.