ProxyPay - AI-Powered Programmable On-Chain Payments

Create automated on-chain payment rules using natural language. Non-custodial, permissionless, and fully on-chain — powered by MNEE stablecoin and AI.

Comment

Inspiration

The world of on-chain payments is fragmented and complex. Users need to manually execute transactions, remember payment schedules, and navigate complicated DeFi interfaces. We asked ourselves: What if anyone could automate payments just by describing what they want in plain English?

Inspired by the vision of programmable money, we built ProxyPay — a platform where payment rules live on-chain, execution is permissionless, and AI handles the complexity of translating human intent into smart contract logic.

What it does

ProxyPay enables users to create automated, on-chain payment rules using natural language. Simply describe your payment in plain English:

"Pay 10 MNEE to my developer every week, with a max of 100 MNEE total"

Our AI (powered by Google Gemini) parses your intent and creates a smart contract rule with:

  • Recipient address
  • Payment amount
  • Time intervals (minutes, hours, days, weeks, months)
  • Spending limits (enforced on-chain)

Once created, anyone can trigger the execution when conditions are met — making it truly permissionless and automated.

Key Features

  • 🔐 Non-Custodial: The server never holds private keys or has custody of your funds
  • ⚡ Permissionless Execution: Anyone can trigger rule execution when conditions are met
  • 🔗 100% On-Chain: Smart contracts validate and enforce all conditions
  • 🤖 AI-Powered: Natural language → structured payment rules via Gemini AI
  • 💰 Spending Limits: Maximum spending caps enforced on-chain
  • ⏰ Time-Based Triggers: Recurring intervals enforced by the contract

How we built it

ProxyPay is a full-stack application with three main components:

1. Smart Contracts (Solidity + Foundry)

  • MockMNEE.sol: ERC-20 token contract for the MNEE stablecoin
  • ProxyPay.sol: Core payment rules engine with interval enforcement, spending limits, and permissionless execution
  • Comprehensive test suite with Foundry

2. Backend Server (Node.js + Express + TypeScript)

  • RESTful API for rule management
  • Google Gemini AI integration for natural language parsing
  • Viem library for blockchain interactions
  • Intelligent fallback when AI is unavailable

3. Frontend Dashboard (Next.js 16 + React 19 + TypeScript)

  • Beautiful, responsive UI with dark/light theme support
  • Wagmi + Viem for wallet integration
  • Real-time rule monitoring and execution
  • Chat interface for natural language rule creation

Challenges we ran into

  1. Intent Parsing Accuracy: Getting the AI to consistently parse complex payment descriptions (like "pay 50 MNEE every 2 weeks for 6 months") required careful prompt engineering and validation layers.

  2. Permissionless Execution: Designing a smart contract where anyone can trigger execution, but only when conditions are met, required careful security considerations.

  3. Time Interval Enforcement: On-chain time-based logic is tricky. We implemented robust interval checking while keeping gas costs reasonable.

  4. UX for Non-Technical Users: Making blockchain payments accessible through natural language while maintaining transparency about what's happening on-chain.

Accomplishments that we're proud of

  • True Non-Custodial Design: The server is purely a convenience layer — it can never move funds or sign transactions
  • Working End-to-End Flow: From natural language input to on-chain execution, everything works seamlessly
  • Clean Security Model: Clear separation between what the server CAN and CANNOT do
  • Beautiful UI: Premium design with smooth animations and responsive layout

What we learned

  • How to integrate AI with blockchain applications effectively
  • The importance of fallback mechanisms when external APIs fail
  • Designing truly permissionless systems where execution is trustless
  • Building user-friendly interfaces for complex on-chain operations

What's next for ProxyPay

  • Mainnet Deployment: Deploy to BSV mainnet with real MNEE tokens
  • More Payment Conditions: Price triggers, balance thresholds, multi-signature approvals
  • Notification System: Email/push notifications when payments execute
  • Mobile App: Native mobile experience for on-the-go payment management
  • Multi-Token Support: Expand beyond MNEE to other tokens

Built With

Share this project:

Updates