InvisiWallet

"Venmo for Crypto - Send money to @username, never see blockchain"

Comment

InvisiWallet is a mobile‑first, Venmo‑style payments app that hides blockchain complexity while keeping users in self‑custody on Starknet. Users sign up with email, send to @username, and never touch seed phrases, gas, or addresses. Under the hood, we integrate Starknet account abstraction and optional ChiPay checkout for fiat‑like flows.

Why it matters

  • Ultra‑low fees (Starknet), security inherited from Ethereum, and a familiar UX.
  • Bridges Web2 sign‑in with Web3 self‑custody for the next wave of users.
  • Optional privacy mode masks sensitive UI, opening doors for future private tx research.

Features

  • Starknet wallet connect (Argent X / Braavos)
  • On‑chain ERC‑20 transfer via starknet.js, recording tx_hash
  • ChiPay checkout fallback (opens ChiPay checkout if no on‑chain transfer)
  • Off‑chain ledger in Supabase for activity feed and balances
  • Privacy mode (masks balance, usernames, amounts; tags tx note as [private])
  • Invisible wallet creation via ChiPay SDK on user signup
  • Gas sponsorship through ChiPay paymaster

Tech Stack

  • Frontend: React + Vite + TypeScript + Tailwind + shadcn/ui
  • Wallet/Chain: starknet.js (Argent X / Braavos injectors)
  • Backend-as-a-service: Supabase (Auth, DB)
  • Payments: ChiPay Checkout (client‑side), server webhook for production

Project Story

🎯 What Inspired Us

The inspiration for InvisiWallet came from a simple observation: crypto payments still feel worse than Venmo. Despite having superior technology (ultra-low fees, instant settlement, self-custody), mainstream users are blocked by:

  • Complex wallet addresses (0x742d35Cc6634C0532925a3b8D...)
  • Gas fees and transaction failures
  • Seed phrase management nightmares
  • Unfamiliar blockchain terminology

We asked: "What if we could give users the security and sovereignty of crypto with the simplicity of Venmo?"

🏗️ How We Built It

Our approach was to abstract away blockchain complexity while maintaining self-custody:

  1. Invisible Wallets: Every user gets a Starknet wallet created via ChiPay SDK on signup
  2. Username-Based Payments: Send to @username instead of addresses
  3. Gas Sponsorship: ChiPay paymaster covers gas fees for seamless UX
  4. Account Abstraction: Leverage Starknet's native AA for Web2-like features
  5. Hybrid Architecture: On-chain transfers when possible, ChiPay fallback when needed

Technical Architecture:

Frontend (React + starknet.js) 
    ↓
Backend (Node.js + ChiPay SDK)
    ↓
Starknet (Account Abstraction + ERC-20)
    ↓
Supabase (User data + Transaction ledger)

🎓 What We Learned

Starknet Account Abstraction is Powerful:

  • Native support for social recovery and paymasters
  • Seamless wallet connection with Argent X/Braavos
  • Gas sponsorship enables fee-less user experience

ChiPay Integration Challenges:

  • API documentation gaps required trial-and-error
  • Environment variable management across frontend/backend
  • Webhook handling for transaction reconciliation

User Experience Insights:

  • Privacy mode is crucial for mainstream adoption
  • Transaction transparency (showing both DB and blockchain records) builds trust
  • Dark theme and modern UI significantly improve perceived quality

🚧 Challenges We Faced

Technical Challenges:

  1. Starknet.js Learning Curve

    • Complex wallet connection flow with multiple providers
    • RPC endpoint compatibility issues
    • Transaction signing and execution nuances

  2. ChiPay API Integration

    • Limited documentation for server-side SDK
    • Environment variable configuration complexity
    • Webhook implementation for transaction status updates

  3. Database Schema Evolution

    • Adding starknet_address column to existing profiles
    • Transaction type enum limitations in PostgreSQL
    • Real-time transaction updates with Supabase

  4. Frontend State Management

    • Coordinating wallet connection with user authentication
    • Managing on-chain vs off-chain transaction states
    • Privacy mode implementation across all components

What We Failed to Achieve:

  1. Complete Social Recovery

    • Goal: Email/OTP-based wallet recovery
    • Reality: Implemented basic account abstraction but not full social recovery
    • Why: Time constraints and complexity of Starknet AA implementation

  2. Real-Time Transaction Updates

    • Goal: Live transaction status updates via webhooks
    • Reality: Manual refresh required for transaction status
    • Why: ChiPay webhook integration complexity and time limits

  3. Mobile App

    • Goal: Native mobile app for better UX
    • Reality: Web app only (though mobile-responsive)
    • Why: Focused on core functionality over platform expansion

  4. Advanced Privacy Features

    • Goal: Private transactions with no trace
    • Reality: Basic privacy mode (UI masking only)
    • Why: Starknet privacy features require additional research

🏆 What We Achieved

Core Functionality:

✅ Invisible Wallet Creation: Automatic Starknet wallet provisioning via ChiPay SDK
✅ Username-Based Payments: Send to @username instead of addresses
✅ Real On-Chain Transfers: Actual ERC-20 token transfers with tx_hash recording
✅ Gas Sponsorship: ChiPay paymaster integration for fee-less transactions
✅ Hybrid Payment Flow: On-chain when possible, ChiPay fallback when needed

User Experience:

✅ Venmo-Like Interface: Familiar payment flow with modern dark theme
✅ Privacy Mode: Mask sensitive information for privacy-conscious users
✅ Transaction Transparency: Separate tabs for database vs blockchain records
✅ Wallet Integration: Seamless Argent X/Braavos connection

Technical Excellence:

✅ Production-Ready Code: No demo/mock modes, real API integrations
✅ Error Handling: Graceful fallbacks and user-friendly error messages
✅ Responsive Design: Mobile-first approach with beautiful UI
✅ Type Safety: Full TypeScript implementation with proper interfaces

🔮 Future Vision

Short Term:

  • Complete social recovery implementation
  • Real-time webhook integration
  • Mobile app development

Long Term:

  • Cross-chain compatibility
  • Advanced privacy features
  • DeFi integration (lending, staking)
  • Merchant payment processing

💡 Key Innovation

Our core innovation is the "Invisible Wallet" concept - users get the security and sovereignty of self-custody without any blockchain complexity. This bridges the gap between Web2 convenience and Web3 benefits, making crypto payments accessible to mainstream users.

The magic happens when users don't even know they're using blockchain technology, but they still maintain full control of their funds.

Built With

Share this project:

Updates