AI Coding Challenge Platform

A full-stack AI-powered coding challenge platform. Users log in, select a difficulty, and receive a dynamically generated multiple-choice coding challenge — no static database required. Every challenge is unique, produced in real time by an OpenAI pipeline. User sessions, challenge history, and daily quotas are all persisted and tracked.

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✨ Features

• 🤖 AI-Generated Challenges — GPT produces unique coding questions on every request, eliminating the need for a static challenge database
• 🔐 Clerk Authentication — Full sign-in/sign-up flow with session management split across frontend and backend
• 📊 Challenge History — Each user's past attempts, answers, and results are stored and displayed in a History panel
• ⚡ Daily Quota System — Tracks and limits the number of challenges per user per day (resets every 24 hours)
• 🛡️ Route Protection — Authentication enforced at a granular level on the frontend; protected API endpoints on the backend
• 🔒 Secure by Design — API keys stored in .env files excluded from version control; CORS middleware restricts requests to the frontend domain only

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📸 Preview

Sign In

Generate a Challenge

Challenge History

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🏗️ Architecture

┌─────────────────────┐         ┌──────────────────────┐
│   React (Vite)      │ ──────▶ │   FastAPI (Python)   │
│   Plain CSS         │         │   Uvicorn server     │
│   Clerk React SDK   │         │   SQLAlchemy ORM     │
└─────────────────────┘         └──────────┬───────────┘
                                            │
                          ┌─────────────────┼──────────────────┐
                          ▼                 ▼                  ▼
                    OpenAI API         Clerk Webhooks       SQLite DB
                  (challenge gen)    (user session sync)  (persistence)

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🗂️ Project Structure

AI-Coding-Challenge-Platform/
├── backend/
│   ├── server.py              # Entry point - starts Uvicorn
│   ├── pyproject.toml         # Python dependencies
│   └── src/
│       ├── app.py             # FastAPI app - CORS, routers
│       ├── ai_generator.py    # OpenAI integration - challenge generation
│       ├── utils.py           # Clerk request authentication helper
│       ├── database/
│       │   ├── models.py      # SQLAlchemy ORM models + DB setup
│       │   └── db.py          # DB query functions
│       └── routes/
│           ├── challenge.py   # /api/generate-challenge, /api/my-history, /api/quota
│           └── webhook.py     # /webhooks/clerk - user creation sync
├── frontend/
│   └── src/
│       ├── main.jsx           # App entry - ClerkProvider wrapper
│       ├── App.jsx            # Root component and routing
│       ├── app.css            # Global styles
│       ├── auth/
│       │   ├── ClerkProviderWithRoutes.jsx  # Route protection wrapper
│       │   └── AuthenticationPage.jsx       # Sign-in / sign-up UI
│       ├── challenge/
│       │   ├── ChallengeGenerator.jsx       # Main challenge interface
│       │   └── MCQChallenge.jsx             # Multiple choice question display
│       ├── history/
│       │   └── HistoryPanel.jsx             # User history view
│       ├── layout/
│       │   └── Layout.jsx                   # Navbar and page shell
│       └── utils/
│           └── api.js                       # Authenticated fetch helper
└── README.md

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🚀 Getting Started

Prerequisites

• Python 3.14+
• Node.js 18+
• An OpenAI API key
• A Clerk account

Backend Setup

cd backend
pip install .

Create a .env file inside backend/:

OPENAI_API_KEY=your_openai_api_key
CLERK_SECRET_KEY=your_clerk_secret_key
CLERK_WEBHOOK_SECRET=your_clerk_webhook_secret

Start the server:

python server.py

API available at http://localhost:8000

Frontend Setup

cd frontend
npm install

Create a .env file inside frontend/:

VITE_CLERK_PUBLISHABLE_KEY=your_clerk_publishable_key

Start the dev server:

npm run dev

App available at http://localhost:5173

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📡 API Endpoints

Method	Endpoint	Description
POST	/api/generate-challenge	Generate a new AI challenge {"difficulty": "easy|medium|hard"}
GET	/api/my-history	Get the authenticated user's challenge history
GET	/api/quota	Get the authenticated user's remaining daily quota
POST	/webhooks/clerk	Clerk webhook - creates quota record on user sign-up

All /api/* endpoints require a valid Clerk session token.

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🛠️ Tech Stack

Layer	Technology
Frontend	React (Vite), Plain CSS, Clerk React SDK
Backend	FastAPI, Uvicorn, Python 3.14+
Auth	Clerk (session management, webhooks, route protection)
AI	OpenAI GPT (dynamic challenge generation)
Database	SQLite, SQLAlchemy ORM