Quantum Unified Simulator (QCanvas)

A comprehensive quantum computing platform that provides unified simulation, circuit conversion, and visualization capabilities across multiple quantum frameworks using a hybrid Next.js and FastAPI architecture.

🚀 Overview

QCanvas is a modern, web-based quantum computing platform that bridges the gap between different quantum computing frameworks. It provides a unified interface for simulating quantum circuits, converting between different quantum programming languages, and visualizing quantum states and operations.

Key Features

• Multi-Framework Support: Convert circuits between Cirq, Qiskit, and PennyLane
• Hybrid CPU–QPU Model: QCanvas orchestrates; QSim executes (simulator-first, pluggable QPU later)
• Real-Time Simulation: Execute quantum circuits with statevector, density matrix, or stabilizer backends
• OpenQASM 3.0 (Rosetta Stone): Universal intermediate representation across frameworks
• Smart Conversion Engine: AST-based parsing, intelligent gate mapping, built-in validation, instant analytics
• Interactive Visualization: Circuit rendering, histograms, and results analysis
• Shared TypeScript Types: Type safety across frontend and backend services
• Extensible Architecture: Plugin-based system for adding new frameworks

🏗️ Architecture

QCanvas/
├── frontend/             # Next.js-based web interface
│   ├── app/              # App Router pages and layouts
│   ├── components/       # Reusable UI components
│   ├── lib/              # Utility functions and state management
│   └── public/           # Static assets (images, icons)
│
├── backend/              # FastAPI REST API and WebSocket server
│   ├── app/              # Main application logic
│   │   ├── api/          # API routes and endpoints
│   │   ├── models/       # Database models and Pydantic schemas
│   │   └── services/     # Business logic services
│   └── alembic/          # Database migration scripts
│
├── quantum_converters/   # Framework conversion modules
│   ├── qiskit/           # Qiskit to OpenQASM converters
│   ├── cirq/             # Cirq to OpenQASM converters
│   └── pennylane/        # PennyLane to OpenQASM converters
│
├── quantum_simulator/    # Quantum simulation engine
│   ├── backends/         # Simulation backends (statevector, density matrix)
│   └── core/             # Core simulation logic
│
├── examples/             # Sample circuits and tutorials
│
├── docs/                 # Project documentation
│
├── tests/                # Comprehensive test suite
│
└── scripts/              # Helper scripts for setup and maintenance

Core Components

1. QCanvas (Compilation/Orchestration): AST parsing, QASM generation, validation, hybrid scheduling
2. QSim (Execution): High-performance simulation backends and result aggregation
3. Next.js Frontend: UI components, routing, and simple operations
4. FastAPI Backend: API, WebSockets, and heavy computations
5. Shared TypeScript Types: Type safety across frontend and backend

🛠️ Installation

Prerequisites

• Python 3.9+
• Node.js 18+ (for Next.js)
• Docker Engine with Compose V2 (docker compose CLI)
• Git

Docker and Docker Compose

The repo includes docker-compose.yml for PostgreSQL, Redis, QCanvas FastAPI backend, Cirq-RAG-Code-Assistant (Cirq AI / Bedrock), and optionally SonarQube (metrics profile).

The Next.js frontend is not in Compose; run it locally with npm run dev in frontend/ (see below).

Service overview

Service	Container name	Host port	Notes
PostgreSQL	qcanvas_postgres	5433 → 5432	Database for QCanvas
Redis	qcanvas_redis	6379	Caching
Cirq AI	qcanvas_cirq_agent	8001 → 8000	Bedrock/RAG; internal URL http://cirq_agent:8000
QCanvas API	qcanvas_backend	8000	Sets CIRQ_AGENT_URL=http://cirq_agent:8000
SonarQube	qcanvas_sonarqube	9000	Only with --profile metrics

Each container can use port 8000 internally without conflict; they are isolated. Only host ports must be unique (8000 vs 8001).

Environment file (project root)

Create a .env in the repository root (Compose loads it automatically). Minimum for the database:

POSTGRES_USER=postgres
POSTGRES_PASSWORD=postgres
POSTGRES_DB=qcanvas_db

For Cirq AI inside Docker, add the same variables you use for Bedrock (see Cirq-RAG-Code-Assistant/.env.example):

AWS_ACCESS_KEY_ID=...
AWS_SECRET_ACCESS_KEY=...
AWS_DEFAULT_REGION=us-east-1
BEDROCK_INFERENCE_PROFILE_ARN_DESIGNER=...
BEDROCK_INFERENCE_PROFILE_ARN_OPTIMIZER=...
BEDROCK_INFERENCE_PROFILE_ARN_VALIDATOR=...
BEDROCK_INFERENCE_PROFILE_ARN_EDUCATIONAL=...

Put AWS keys in Cirq-RAG-Code-Assistant/.env when using Docker: that file is bind-mounted into the cirq_agent container as /app/.env. The Compose file does not set AWS_ACCESS_KEY_ID / AWS_SECRET_ACCESS_KEY to empty defaults anymore—empty values used to block python-dotenv from applying the mounted file.

Commands (run from the repo root)

Build images and start the default stack (postgres, redis, cirq_agent, backend):

docker compose up -d --build

Start or restart without rebuilding images:

docker compose up -d

Include SonarQube (metrics profile):

docker compose --profile metrics up -d --build

Rebuild only specific services (e.g. after changing a Dockerfile):

docker compose build cirq_agent backend
docker compose up -d

Force a clean rebuild (slower; use when dependencies change):

docker compose build --no-cache cirq_agent backend
docker compose up -d

View running services:

docker compose ps

Follow logs (all services or one):

docker compose logs -f
docker compose logs -f backend
docker compose logs -f cirq_agent

Stop containers (keeps named volumes such as database data):

docker compose stop

Stop and remove containers (keeps volumes unless you add -v):

docker compose down

Stop and remove containers and volumes (⚠️ deletes Postgres/Redis/SonarQube data):

docker compose down -v

Run a one-off command in the backend container (example: open a shell):

docker compose exec backend bash

After Docker is up

• API: http://localhost:8000 — docs: http://localhost:8000/docs
• Health: http://localhost:8000/api/health
• Cirq AI (direct): http://localhost:8001/docs

Run database migrations against the Dockerized Postgres (from host, with venv and PYTHONPATH set, or exec into backend):

# Example from host (Windows PowerShell); adjust path and venv
$env:PYTHONPATH = "D:\path\to\QCanvas\backend"
$env:DATABASE_URL = "postgresql://postgres:postgres@127.0.0.1:5433/qcanvas_db"
python -m alembic -c backend/alembic.ini upgrade head

Then start the frontend:

cd frontend
npm install
npm run dev

Open http://localhost:3000

Windows Setup (Recommended for Development)

1. Clone Repository

git clone https://github.com/Umer-Farooq-CS/QCanvas.git
cd QCanvas

2. Create Virtual Environment

python -m venv qcanvas_env
.\qcanvas_env\Scripts\activate

3. Install Dependencies

pip install -r requirements.txt

4. Start Docker Services

Use Docker Compose as described in Docker and Docker Compose (e.g. docker compose up -d --build). For SonarQube, add --profile metrics.

5. Set Up Database Schema

# From repo root; set path to your clone
$env:PYTHONPATH = "D:\path\to\QCanvas\backend"
# If Postgres is the Docker Compose service (mapped to host 5433):
$env:DATABASE_URL = "postgresql://postgres:postgres@127.0.0.1:5433/qcanvas_db"

python -m alembic -c backend/alembic.ini upgrade head

6. Create Admin User (Optional)

python backend/create_user.py

Follow prompts to create an admin account.

7. Create Demo Account (Optional)

python backend/create_demo_account.py

This creates a demo account (demo@qcanvas.dev / demo123) for testing. Demo data is cleared on logout.

8. Verify Database

python backend/verify_database.py

📚 For detailed information about database architecture, security (CIA principles), and troubleshooting, see docs/db_setup.md

9. Start Backend Server

If you already use Docker Compose for the API, skip this step (backend is on http://localhost:8000).

$env:PYTHONPATH="d:\path\to\QCanvas\backend"
python backend/start.py

Backend will run on http://localhost:8000

• API Docs: http://localhost:8000/docs
• Health Check: http://localhost:8000/api/health

Cirq AI assistant (optional): The IDE can proxy to Cirq-RAG-Code-Assistant. Run the Cirq service on port 8001 (QCanvas already uses 8000). Set CIRQ_AGENT_URL in the QCanvas backend environment (defaults to http://127.0.0.1:8001). The frontend calls {QCanvas API}/api/cirq-agent/api/v1/.... For local UI-only testing without the QCanvas API proxy, set NEXT_PUBLIC_CIRQ_USE_NEXT_REWRITE=true and optionally CIRQ_REWRITE_TARGET (Next.js rewrites /cirq-api/* to the Cirq server).

10. Start Frontend (New Terminal)

cd frontend
npm install
npm run dev

Frontend will run on http://localhost:3000

Linux Quick Setup (Recommended)

For a fresh Linux machine, you can install all requirements and start QCanvas using the provided scripts:

1. Clone the repository

   git clone https://github.com/Umer-Farooq-CS/QCanvas.git
   cd QCanvas
   

2. Run first‑time setup

   # Installs system packages, creates venv, installs backend + frontend deps
   bash setup.sh
   

3. Configure environment

   cp environment.env.example environment.env
   # Edit environment.env with your configuration
   

4. Start/stop QCanvas in the background

   # Start Next.js frontend and FastAPI backend in background
   ./run.sh start
   
   # Stop all QCanvas services (kills node/next/uvicorn and clears PID files)
   ./run.sh stop
   

   • Background logs are written to logs/frontend.log and logs/backend.log.
   • PID files frontend.pid and backend.pid are used to avoid double‑starting services.

📡 API Usage

Conversion API

Endpoint: POST /api/converter/convert

Convert quantum circuit code from a specific framework to OpenQASM 3.0.

{
  "source_code": "from qiskit import QuantumCircuit\nqc = QuantumCircuit(2)\nqc.h(0)\nqc.cx(0, 1)",
  "source_framework": "qiskit",
  "conversion_type": "classic"
}

Response:

{
    "success": true,
    "qasm_code": "OPENQASM 3.0;...",
    "framework": "qiskit",
    "conversion_stats": { ... }
}

Simulation API (QSim)

Endpoint: POST /api/simulator/execute

Execute OpenQASM 3.0 code using the QSim engine with various backends.

{
  "qasm_code": "OPENQASM 3.0; include \"stdgates.inc\"; qubit[2] q; bit[2] c; h q[0]; cx q[0], q[1]; c = measure q;",
  "backend": "cirq",  // Options: "cirq", "qiskit", "pennylane"
  "shots": 1024
}

Response:

{
    "success": true,
    "counts": { "00": 512, "11": 512 },
    "metadata": { ... }
}

🔧 Configuration

Environment Variables

• DATABASE_URL: PostgreSQL connection string
• REDIS_URL: Redis connection string for caching
• SECRET_KEY: Application secret key
• DEBUG: Enable debug mode (True/False)
• ALLOWED_HOSTS: Comma-separated list of allowed hosts
• NEXT_PUBLIC_API_URL / NEXT_PUBLIC_API_BASE: Frontend API endpoint for Next.js
• CIRQ_AGENT_URL: QCanvas backend proxy target for Cirq AI (Compose sets http://cirq_agent:8000 inside Docker; locally often http://127.0.0.1:8001)

🧪 Testing

Run Tests

# Run all tests
pytest

# Run specific test categories
pytest tests/unit/
pytest tests/integration/
pytest tests/e2e/

# Run frontend tests
cd frontend
npm test

# Run with coverage
pytest --cov=quantum_converters --cov=quantum_simulator --cov=backend

📚 Documentation

• API Documentation
• User Guide
• Developer Guide
• Deployment Guide

🤝 Contributing

We welcome contributions! Please see our Contributing Guide for details.

📄 License

This project is licensed under the Open Quantum Workbench Proprietary License. See the LICENSE file for details.

👥 Teams

QCanvas Team

• Umer Farooq
• Hussan Waseem Syed
• Muhammad Irtaza Khan

QSim Team

• Aneeq Ahmed Malik
• Abeer Noor
• Abdullah Mehmood

Supervisors

• Dr. Imran Ashraf (Project Supervisor)
• Dr. Muhammad Nouman Noor (Co-Supervisor)

Built under Open Quantum Workbench: A FAST University Initiative