✨ CodeVerdict - Open-Source Coding Exam Platform

Self-host your own coding exam platform with live leaderboards, ICPC scoring, and instant code execution. CodeVerdict is a production-grade, open-source online coding examination platform built with NestJS, Vue 3, and PostgreSQL. Students solve programming problems in a Monaco-powered editor, get instant multi-test-case feedback via a self-hosted Judge0 executor, and compete on a real-time ICPC-scored leaderboard. Administrators create and manage exams, problems, and test cases through a dedicated panel.

🚀 Battle-tested in production: 90,000+ requests handled in a 2-hour exam window with just 2 replicas - 99.99% success rate (9 failures out of 90,200 requests). 120+ concurrent users taking exams simultaneously.

Fully open-source (AGPL-3.0) and white-label ready - customize branding (logo, app name, colors, copyright) via environment variables. No code changes needed.

Open-source alternative to HackerRank, CodeSignal, HackerEarth, LeetCode, Codility, TestDome, CoderPad, CodeChef, and Codeforces. CodeVerdict gives you full control - self-host on your own infrastructure, own your data, white-label everything, and pay nothing.

Preview

Student Portal - Landing page once an exam is configured and live. Students see the contest details, rules, and timing at a glance. Hit Enter Contest to register via the API and jump straight into the coding environment.

Admin Panel - Exam Management

Create & Manage Exams - Admin dashboard showing all exams with status (Active/Ended), duration, and quick actions. Create new exams, assign problems, view the leaderboard, duplicate existing exams, or delete them - all from one place.

Admin Panel - Problem Bank

Problem Bank - Browse, search, and manage all problems across difficulty levels (Easy, Medium, Hard). Each problem shows time/memory limits, max score, and test case count. Add new problems or edit existing ones with the built-in editor.

Student Portal - Multi-Exam View

Exam Selector - When multiple exams are running simultaneously, students see all available contests on the landing page. Pick an exam, view its schedule and rules, and enter when the window is open.

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Features

• Multiple concurrent exams - run several exams simultaneously with an exam selector
• Server-synced timer - countdown uses server time, preventing client-side manipulation
• Monaco editor - VSCode-quality code editor with syntax highlighting
• Instant feedback - test cases run via Judge0 batch API; per-case verdicts returned
• Run mode - execute code against sample inputs without scoring
• MCQ support - mixed exam formats with coding + multiple-choice
• ICPC scoring - penalty-based scoring, race-condition-safe via database write locks
• Live leaderboard - materialized view, refreshed after every accepted submission
• Autosave - code drafts debounce-saved to the server
• Admin panel - create exams, duplicate them, manage problems and test cases
• White-label branding - app name, logo, colors, copyright - all via env vars
• Swagger docs - full OpenAPI docs at /api-docs in development
• Brotli pre-compression - .br assets generated at build time via Vite plugin

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Architecture

graph LR
    subgraph Client
        Browser["🖥️ Vue 3 SPA\nMonaco Editor + Pinia"]
    end

    subgraph Server
        API["⚡ NestJS API\n:3000/api"]
    end

    subgraph Database
        DB[("🐘 PostgreSQL 17\nexam_platform")]
        LB["📊 Leaderboard\nMaterialized View"]
    end

    subgraph Code Execution
        J0["🔧 Judge0\n:2358"]
        Redis["Redis\nJob Queue"]
    end

    Browser -- "JWT Auth + REST" --> API
    API -- "TypeORM" --> DB
    API -- "Batch Submit\n(base64 encoded)" --> J0
    J0 -- "Verdicts" --> API
    API -- "ICPC Score\n+ Refresh" --> LB
    J0 --- Redis

    style Client fill:#1a1a2e,stroke:#4FC08D,color:#fff
    style Server fill:#1a1a2e,stroke:#E0234E,color:#fff
    style Database fill:#1a1a2e,stroke:#4169E1,color:#fff
    style Code Execution fill:#1a1a2e,stroke:#f5a623,color:#fff

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Layer	Tech
Frontend	Vue 3, Vite 8, Pinia, Monaco Editor, TypeScript
Backend	NestJS 11, TypeORM, Passport JWT, Swagger
Database	PostgreSQL 17, Redis (Judge0 queue)
Infra	Docker Compose, Node 22-alpine, Judge0 1.13.1

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Quick Start

Docker (recommended)

git clone https://github.com/ATOAPaymentsLimited/CodeVerdict.git
cd CodeVerdict
cp .env.example .env         # set DB_PASSWORD, JWT_SECRET, ADMIN_SETUP_KEY
docker compose up --build    # → http://localhost:3000

Local development

# Install
cd server && npm install && cd ../client && npm install && cd ..

# Configure
cp server/.env.example server/.env    # fill in values
cp client/.env.example client/.env    # optional branding

# Run
cd server && npm run start:dev        # → http://localhost:3000
cd client && npm run dev              # → http://localhost:5173 (separate terminal)

Set CORS_ORIGIN=http://localhost:5173 in server/.env when running client and server separately.

Tip: Generate a secure JWT_SECRET with:

node -e "console.log(require('crypto').randomBytes(48).toString('hex'))"

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Environment Variables

All variables are documented in the .env.example files:

File	Purpose
.env.example	Docker Compose - database, JWT, Judge0, admin key
server/.env.example	Local dev - same as above + host/port config
client/.env.example	Branding - app name, logo, colors, copyright

Key required variables: DB_PASSWORD, JWT_SECRET, ADMIN_SETUP_KEY, JUDGE0_URL

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Branding & Customization

The platform is fully white-label. No code changes needed:

1. Logo - drop into client/public/, set VITE_LOGO_PATH
2. App name - set VITE_APP_NAME + APP_NAME
3. Colors - set VITE_PRIMARY_COLOR and VITE_ACCENT_COLOR (hex)
4. Copyright - set VITE_COPYRIGHT_HOLDER

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Deploy to Railway

Railway provisions the app and PostgreSQL automatically. Set JWT_SECRET, ADMIN_SETUP_KEY, and JUDGE0_URL during deploy.

Post-deployment: If you serve the frontend from a different domain, set CORS_ORIGIN to that domain. Otherwise leave it blank.

Judge0 requires privileged Docker containers, so it must be deployed separately:

1. Self-host on a VPS - Judge0 docs
2. Hosted API via RapidAPI

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Production Build

docker build -t codeverdict:latest .

Multi-stage Dockerfile: builds Vue SPA (with Brotli pre-compression) → compiles NestJS → copies both into a minimal node:22-alpine image running as non-root.

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Contributing

Contributions are welcome! 🎉 See CONTRIBUTING.md for setup, coding standards, commit conventions, and the PR process.

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License

GNU Affero General Public License v3.0 (AGPL-3.0) - see LICENSE.

What you can do	What you must do
✅ Use for any purpose (commercial or academic)	📤 Share source code of modifications
✅ Modify and customize freely	📤 Provide source access to network users (SaaS/hosted)
✅ Distribute copies	📄 Keep the same AGPL-3.0 license on derivatives
✅ Self-host for your institution	📝 State changes you made

In plain terms:

• Universities and schools - self-host freely, customize branding, no cost ever.
• Companies running it as a service - you must open-source your modifications.
• Contributors - your work stays open and can never be taken proprietary.