Building AI Workflows with FastAPI and LangGraph (Step-by-Step Guide)
Last Updated on August 28, 2025 by Editorial Team
Author(s): GenAI Lab
Originally published on Towards AI.
Building AI Workflows with FastAPI and LangGraph (Step-by-Step Guide)
Large Language Models (LLMs) are great at reasoning, but real-world applications often require stateful, multi-step workflows. That’s where LangGraph comes in — it lets you build intelligent workflows using graphs of LLM-powered nodes.
This article provides a comprehensive step-by-step guide on creating and deploying AI workflows using LangGraph and FastAPI, starting from project setup, through building a simple LangGraph workflow, to making it production-ready with features like error handling and input validation. It explains how to expose the workflows as REST APIs, test them, and prepare the application for production, including considerations for scaling and deployment.
Read the full blog for free on Medium.
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