FitSync

Full-stack fitness tracker that logs meals and workouts with real nutrition data and AI-powered coaching insights.

Live: fitsync-5tf7.onrender.com

DEMO : Demo

Built By

Chimdinma Jason — designed and built end-to-end as my capstone project for the Meta University Engineering Internship, Summer 2025. Presented to Meta leadership at end-of-program showcase.

About

FitSync is a clean, free alternative to paywalled fitness apps. Users log meals (pulled from the Nutritionix API for real nutrition data), log workouts, and track their daily calories in/out with weekly progress charts. An AI chat assistant powered by Gemini provides personalized coaching insights.

Tech Stack

• Frontend: React, Tailwind CSS
• Backend: Node.js, Express
• Database: PostgreSQL + Prisma
• Auth: JWT-secured sessions + Firebase Auth
• Real-Time: WebSockets (live workout state sync)
• APIs: Nutritionix (food data), Gemini (AI coaching)
• Deployment: Render

Features

• Email/password signup with JWT-secured sessions
• Food search with real nutrition data via the Nutritionix API
• Meal and workout logging with full CRUD
• Daily calories in/out/net summary
• Weekly progress charts
• LLM-generated personalized workout plans
• WebSocket-based live sync (workout state stays consistent across sessions)
• AI chat assistant (Gemini) for personalized coaching

Local Development

Backend

cd server
npm install
npm run dev

Frontend

cd client
npm install
npm run dev

Required environment variables (see .env.example):

• DATABASE_URL (PostgreSQL connection string)
• NUTRITIONIX_APP_ID and NUTRITIONIX_APP_KEY
• GEMINI_API_KEY
• FIREBASE_* config keys
• JWT_SECRET

Architecture

React client communicates with Express backend via REST + WebSocket. PostgreSQL stores user data via Prisma ORM. Nutritionix powers food search; Gemini powers the AI assistant. Firebase Auth manages sessions alongside JWT.