Best of FastAPI — September 2025

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   Article

   Daily Dose of Data Science | Avi Chawla | Substack·34w

   Building a Full-stack Agentic App

   AG-UI is an open-source protocol that enables communication between AI agents and frontend interfaces through event-based messaging. The tutorial demonstrates building a stock portfolio agent using CrewAI Flows for the backend and CopilotKit for the frontend, featuring real-time streaming, human-in-the-loop approval, and reactive UI updates. The implementation includes a 5-step workflow covering portfolio initialization, investment parameter extraction, stock data simulation, allocation calculation, and insights generation.

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2. 2
   Article

   Towards Data Science·35w

   How to Build an AI Budget-Planning Optimizer for Your 2026 CAPEX Review: LangGraph, FastAPI, and n8n

   A comprehensive guide to building an AI-powered budget planning system that automates CAPEX portfolio optimization. The solution combines LangGraph for agent orchestration, FastAPI for linear programming optimization, and n8n for workflow automation. Users can send budget requests via email and receive optimized project portfolios that maximize ROI while respecting constraints like sustainability requirements. The system includes email parsing, mathematical optimization using PuLP library, and automated report generation for executive decision-making.

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3. 3
   Article

   Planet Python·32w

   TIL: Loading .env files with uv run

   The uv package manager includes built-in support for loading environment variables from .env files using the --env-file flag with uv run, eliminating the need for python-dotenv dependency. This feature allows developers to specify different environment files for various deployment stages and works seamlessly with frameworks like FastAPI.

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