UniCash Browser Wallet

WebGPU-Accelerated Post-Quantum Blockchain Wallet

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Overview

The UniCash wallet is a Progressive Web App (PWA) that enables users to:

• Generate post-quantum cryptographic keys (Dilithium)
• Create and sign transactions
• Generate zero-knowledge proofs using WebGPU
• Fallback to CPU proving (WASM) for unsupported devices

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Architecture

wallet/
├── src/
│   ├── App.tsx              # Main React application
│   ├── main.tsx             # Entry point
│   ├── index.css            # Styles
│   ├── webgpu/
│   │   ├── prover.ts        # WebGPU proof generation
│   │   └── shaders/
│   │       ├── ntt.wgsl     # Number Theoretic Transform
│   │       └── fri.wgsl     # FRI folding
│   └── wasm/
│       └── crypto.ts        # WASM crypto bridge
├── public/
│   └── wasm/                # Compiled WASM modules
├── package.json
├── vite.config.ts
└── tsconfig.json

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Quick Start

Prerequisites

• Node.js 18+ and npm
• Rust and wasm-pack (for building WASM)
• Modern browser with WebGPU support

Installation

cd unicash-mvp/wallet

# Install dependencies
npm install

# Build WASM module
npm run wasm:build

# Start development server
npm run dev

Open http://localhost:3000 in your browser.

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Building WASM Module

The wallet uses Rust compiled to WebAssembly for cryptographic operations:

# Install wasm-pack (one time)
cargo install wasm-pack

# Build WASM module
cd unicash-mvp
wasm-pack build --target web --out-dir wallet/public/wasm wasm-crypto

# Or use npm script
cd wallet
npm run wasm:build

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WebGPU Support

Supported Browsers (2026)

Browser	Version	WebGPU Support
Chrome	113+	✅ Full support
Edge	113+	✅ Full support
Safari	17+	✅ Full support
Firefox	120+	⚠️ Experimental

Checking WebGPU Support

The wallet automatically detects WebGPU support:

if (!navigator.gpu) {
  console.log('WebGPU not supported, falling back to CPU');
}

Fallback Strategy

1. WebGPU (preferred): <1s proof generation
2. WASM CPU: 3-5s proof generation
3. Delegated proving: Send to prover network (future)

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WGSL Shaders

NTT Shader (ntt.wgsl)

Performs Number Theoretic Transform on M31 field:

• Cooley-Tukey FFT algorithm
• Optimized for GPU parallelism
• Handles up to 2^20 elements

FRI Shader (fri.wgsl)

Implements FRI folding for Circle STARKs:

• Polynomial degree reduction
• Query evaluation
• Commitment generation

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Performance Targets

Device	Method	Proof Time	Status
Desktop GPU	WebGPU	<1s	✅ Target
Mobile GPU	WebGPU	<3s	✅ Target
Desktop CPU	WASM	3-5s	✅ Acceptable
Mobile CPU	WASM	5-10s	⚠️ Slow

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Development

Running Tests

# Unit tests
npm test

# WASM tests
cd ../wasm-crypto
cargo test --target wasm32-unknown-unknown

Building for Production

# Build optimized bundle
npm run build

# Preview production build
npm run preview

Debugging

Enable verbose logging:

// In browser console
localStorage.setItem('debug', 'unicash:*');

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Security Considerations

Key Storage

• Keys stored in browser's IndexedDB
• Encrypted with user password
• Never sent to server

Proof Generation

• All computation happens locally
• No data leaves the device
• Proofs are zero-knowledge (reveal nothing)

Network Communication

• All RPC calls use HTTPS
• WebSocket connections use WSS
• P2P connections use libp2p encryption

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Browser Compatibility

Required Features

• WebAssembly (all modern browsers)
• WebGPU (Chrome 113+, Safari 17+)
• IndexedDB (for key storage)
• Web Workers (for background tasks)

Progressive Enhancement

The wallet works on all devices but performs best with:

• WebGPU support (10x faster proving)
• 4GB+ RAM
• Modern GPU (2020+)

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Troubleshooting

"WebGPU not supported"

Solution: Use a supported browser or enable experimental features:

• Chrome: chrome://flags/#enable-unsafe-webgpu
• Firefox: about:config → dom.webgpu.enabled

"WASM module failed to load"

Solution: Rebuild WASM module:

npm run wasm:build

"Proof generation too slow"

Solution:

1. Check if WebGPU is enabled
2. Close other GPU-intensive applications
3. Use delegated proving (future feature)

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Roadmap

Phase 1 (Current)

• ✅ Basic UI
• ✅ WebGPU detection
• ✅ WASM crypto bridge
• ⏳ WGSL shader implementation

Phase 2 (Next)

• Transaction creation
• Balance display
• Transaction history
• QR code support

Phase 3 (Future)

• Staking interface
• Multi-signature support
• Hardware wallet integration
• Mobile app (React Native)

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Contributing

See CONTRIBUTING.md for development guidelines.

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License

Apache 2.0 - See LICENSE for details.

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Built with ❤️ for a post-quantum future

Unicash-WGSL-wallet