I started building out the backend for SmartCart, focusing on getting the barcode scanning and meal plan updates working together. Using FastAPI, I set up the initial API endpoints to handle barcode scans, pull product details from the Open Food Facts (OFF) API, and return structured grocery data. To make meal plans adjust in real-time, I began integrating LangChain, which takes the scanned items, checks them against the planned meals, and queries Spoonacular for substitutions if an ingredient is missing. Next week I want to focus more on the database side, to set up a PostgreSQL schema to store scanned products, user dietary preferences, and updated meal plans, along with basic CRUD operations for easy data access. The main challenges are making sure FastAPI, LangChain, Spoonacular, and OFF API communicate smoothly, improving query efficiency, and ensuring grocery matching happens in real-time without delays.