🕶️ GhostPay — Private P2P Payments (Stealth Addresses & Encrypted Memos)

GhostPay is a cyberpunk-inspired prototype for private peer-to-peer payments, built with Python.
It demonstrates stealth address derivation, end-to-end encrypted memos, and claimable transaction links — designed to explore privacy concepts for next-gen payment rails.

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🧩 Key Features

• 🔐 One-time stealth address generation using X25519 (Diffie-Hellman)
• 📨 Encrypted memos secured with ChaCha20-Poly1305 (PyNaCl)
• 🧾 Claimable payment links to simulate off-chain message passing
• ⚙️ Modular cryptographic primitives — easy to integrate or extend
• 🧠 Designed as a learning and research prototype (not production code)

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🗂️ Repository Structure

ghostpay/

├── src/

│ ├── keygen.py # Generate base + ephemeral key pairs

│ ├── dh_shared.py # Compute shared secrets via X25519

│ ├── encrypt.py # Encrypt/decrypt memos (ChaCha20-Poly1305)

│ ├── onetime_key.py # Derive stealth address for each payment

│ ├── sender_example.py # Example: sender encrypts & sends payment

│ └── receiver_example.py # Example: receiver decrypts memo

├── .gitignore

├── requirements.txt

└── README.md

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⚡ Quick Start

1. Clone the repository

git clone https://github.com/Wanbogang/ghostpay.git
cd ghostpay

2. Create virtual environment

python3 -m venv venv
source venv/bin/activate   # (Linux / macOS)
# or
venv\Scripts\activate      # (Windows)

3. Install dependencies

pip install -r requirements.txt

4. Run examples

Sender encrypts and creates payment link

python src/sender_example.py

Receiver decrypts and reads memo

python src/receiver_example.py

🧠 How It Works

1. Key Generation — each participant (Alice & Bob) generates a base X25519 key pair.

2. Stealth Address Derivation — Alice uses Bob’s public key and a fresh ephemeral key to derive a one-time address.

3. Memo Encryption — Alice encrypts the transaction memo using the shared secret (Diffie-Hellman output).

4. Claim Process — Bob scans for payments addressed to his derived keys and decrypts memos using his private base key.

🧪 Cryptographic Primitives

Component	Algorithm	Library
Key Exchange	X25519	PyNaCl
Encryption	ChaCha20-Poly1305	PyNaCl
Hashing	SHA-256	hashlib
Encoding	Base58 / Base64	Python stdlib

🛡️ Disclaimer

GhostPay is an educational prototype, not a financial product. Do NOT use it for real transactions or sensitive data. The project aims to explore privacy-enhancing cryptography concepts.

🧑‍💻 Author

Wanbogang Labs Cyberpunk sandbox for next-generation privacy systems. GitHub: https://github.com/Wanbogang

Demo & Pitch Deck

• 🎥 Demo video: https://youtu.be/rsHYp0HeCMs
• 🧾 Pitch deck (PDF): ./docs/GhostPay_PitchDeck.pdf