MeshTab ⚡

Close the tab. Keep the friends.
Cross-currency group expense netting with one-tap on-chain settlement on Monad Testnet.
Built for the Monad Metropolis 2026 Hackathon — Consumer Products & Payments Track

💡 The Problem & The Solution

The Problem: Traditional group expense apps (like Splitwise) create tangled, crisscrossing I.O.U. webs. When a trip ends, friends are forced to execute dozens of redundant cross-transfers, calculate complex currency fees, or chase each other across banking apps. Worse, existing crypto expense tools burden non-crypto users with gas tokens, seed phrases, network popups, and raw hex addresses.

The Solution: MeshTab combines high-throughput blockchain infrastructure with consumer fintech simplicity:

Multilateral Netting Engine: An off-chain greedy net-position matching algorithm that computes debtor and creditor positions, collapsing multi-currency debts into minimal direct payments ($\le N-1$ transfers) before on-chain settlement.
Biometric Passkeys & Embedded Smart Accounts: Instant FaceID/TouchID enrollment powered by Privy, generating ERC-4337 smart accounts with zero seed phrases, browser extensions, or popups.
Gasless Agora AUSD Settlement: 1-click debt settlement in Agora AUSD (6-decimal digital dollars) executed through Pimlico Paymasters for 100% sponsored gas on Monad.
Google Gemini Flash Vision AI OCR: Snap a photo of any restaurant receipt, grocery slip, or hotel invoice to instantly extract the total amount and merchant name in ~1 second via @google/genai.
Pyth Network Hermes Multi-Currency FX Engine: Real-time foreign exchange feeds convert EUR, GBP, JPY, CAD, AUD, NGN, and BRL at mid-market rates with 60-second caching and resilient fallback guarantees.
Voice-to-Expense Dictation & Smart Staging: Speak expenses naturally using browser-native Web Speech API. The parser extracts amounts and vendors into an editable staging card for human verification before saving.
Offline-First Resilience & The 3-Mode Architecture: A persistent local outbox (meshTab_testnet_outbox) with operation folding and multi-tab Web Locks synchronizes sequentially (push-first-then-pull) upon reconnection. Operates across 3 isolated modes: sample (Lisbon '24 demo trip), blank (clean sandbox), and testnet (Monad Metropolis live on-chain mode).
Zero-Dependency Procedural Audio: 10 rich micro-interaction sound effects synthesized in real time via the native Web Audio API (AudioContext), eliminating external audio assets and 404 latency.

📊 Feature Maturity Matrix (Live vs. Prototype)

To maintain complete transparency with judges, engineering leadership, and users, MeshTab clearly delineates fully implemented on-chain production features from interactive UX prototypes:

Feature	Category	Current Status & Architecture
MeshTabAgoraLedger Settlement	🟢 Live On-Chain	Deployed on Monad Testnet (`payNettedDebt`). Executes one-tap debt settlement in official Agora AUSD.
Agora AUSD Official Faucet	🟢 Live On-Chain	Official Agora faucet (`requestFunds`) providing 10,000 Agora AUSD for testnet group tabs.
Pimlico Gas Sponsorship	🟢 Live Production	100% gasless transactions via ERC-4337 Paymaster integration with Privy Smart Wallets.
Pyth Hermes FX Engine	🟢 Live Production	Low-latency foreign exchange oracle proxy (`/api/pyth`) with 60s caching and graceful fallbacks.
Gemini Flash Vision OCR	🟢 Live Production	Multimodal receipt scanning endpoint (`/api/receipt-scan`) using Google GenAI SDK.
Upstash Redis + Lua Engine	🟢 Live Production	Atomic serverless transactions (`LUA_ADD_EXPENSE`, `LUA_DELETE_EXPENSE`, `LUA_SETTLE_DEBT`).
Offline Outbox & 2-Way Sync	🟢 Live Production	Local FIFO outbox with operation folding, Web Locks concurrency, and push-first-then-pull reconciliation.
Web Audio Synthesizer	🟢 Live Production	10 custom synthesized sound effects generated procedurally via browser `AudioContext`.
Virtual Visa Card	🟡 Interactive Prototype	Generates card numbers, CVV, expiry, freeze toggles, and spend limits; BaaS card issuance (Stripe Issuing/Lithic) on roadmap.
Agora APY Yield Vault	🟡 Simulated Engine	Real-time mathematical compounding ticker (`Math.pow` @ 4.80% APY); mainnet ERC-4626 smart contract on roadmap.
Fiat Off-Ramp Drawer	🟡 Interactive Prototype	Consumer off-ramp UI featuring Chog security guardrail to prevent confusion between testnet tokens and real fiat bank accounts.
Bluetooth Mesh Transport	🟡 Roadmap Spec	UI specification modal illustrating future handset-to-handset BLE transport without cellular coverage.

📜 Deployed Monad Testnet Contracts

Smart contracts deployed and verified on Monad Testnet (Chain ID: 10143):

Contract	Address	Explorer	Role & Verification
MeshTabAgoraLedger	`0x54f02333ea8D80C175A1C8Bdb71ef709cF424C83`	View on Monadscan	Group debt settlement engine (`payNettedDebt`) for official Agora AUSD
Agora AUSD (Official Token)	`0xa9012a055bd4e0eDfF8Ce09f960291C09D5322dC`	View on Monadscan	Official Agora digital dollar ERC-20 on Monad Testnet (6 decimals)
Agora Official Faucet	`0xd236c18D274E54FAccC3dd9DDA4b27965a73ee6C`	View on Monadscan	Official Agora liquidity faucet dripping 10,000 AUSD per claim (`requestFunds`)

Official Agora AUSD Integration. MeshTab connects 100% directly to official Agora infrastructure on Monad Testnet. Evaluators can fund their smart account with $10,000.00 Agora AUSD in one tap directly from the official Agora Faucet, and settle netted group balances on-chain through MeshTabAgoraLedger (Monadscan Settlement TX, Block 69400512).

🛡️ Judge Evidence Pack & Latency Benchmark: On-chain invariant verification, explorer receipts, and a 10-trial latency study (median 236ms query / ~820ms user tap-to-settle) are compiled in meshtab-artifacts/evidence/EVIDENCE_PACK.md.

🚀 Core Feature Breakdown

Feature	Implementation	Consumer Benefit
🔄 Netting Engine	Off-chain greedy net-position matching rendered on an interactive SVG canvas	Collapses multi-currency group debts into minimal (≤ N-1) direct settlements.
📸 Gemini Vision AI OCR	Google Gemini Flash multimodal vision pipeline via `@google/genai`	Snap a photo of a paper receipt to extract the amount and merchant name in ~1 second.
💱 Pyth Network FX Oracle	Pyth Hermes REST API with 60-second edge revalidation	Split travel expenses in EUR, GBP, JPY, or AUD converted at mid-market rates.
🎙️ Voice-to-Expense Dictation	Browser Web Speech API with currency regex parsing	Dictate `"Paid 45 dollars for groceries"` to pre-fill expenses hands-free.
⛽ Gasless Sponsorship (ERC-4337)	Pimlico Verifying Paymasters + Privy Smart Wallets	Users never hold or spend MON for gas fees; transactions execute seamlessly.
📴 Offline Outbox Engine	FIFO operations queue with multi-tab Web Locks and 2-way server sync	Log tabs and expenses on flights or in subways with optimistic local state.
🤖 MeshBuddy AI Co-Pilot	Floating AI assistant with custom knowledge base and neural TTS	Query tab analytics ("Who owes the most?") with human-like voice responses.
🎵 Procedural Sound Engine	Browser Web Audio API procedural synthesis (10 distinct SFX)	Rich acoustic feedback (clicks, sweeps, success chimes) with zero external asset loading.
💳 Virtual Visa Card (Prototype)	Local state persistence with spending limits and freeze controls	Demonstrates instant POS spendability for settled funds via digital wallet provisioning.
📈 Agora APY Vault (Simulated)	Continuous compounding formula (`4.80% APY`) with live ticking counter	Demonstrates how idle group travel funds earn yield during 7–14 day vacations.

📐 System Architecture

graph TD
    subgraph Client ["Client Layer (Next.js 16 + React 19 + Turbopack)"]
        UI["Consumer UI & Thumb-Zone Dock"]
        VoiceParser["Voice Dictation (Web Speech API)"]
        GeminiOCR["Gemini Flash AI OCR Receipt Scanner"]
        NettingCanvas["Netting Engine (Interactive Visualizer)"]
        Synthesizer["Procedural Sound Synthesizer (Web Audio API)"]
        Outbox["Offline Outbox (Web Locks API + FIFO Queue)"]
    end

    subgraph Auth ["Authentication & Identity"]
        Privy["Privy (Biometric Passkeys, Social, Email)"]
    end

    subgraph AA ["Account Abstraction (ERC-4337)"]
        Pimlico["Pimlico Verifying Paymaster (Gas Sponsorship)"]
        SmartAccount["Monad Smart Account Client (Viem v2)"]
    end

    subgraph Network ["Monad Testnet (Chain ID: 10143)"]
        LedgerContract["MeshTabLedger (0x4340...CA7d)"]
        AUSDContract["Agora AUSD (0xF9bA...957F)"]
    end

    subgraph OraclesAI ["Oracles & AI Infrastructure"]
        Pyth["Pyth Network Hermes (Real-Time FX Feeds)"]
        GoogleGenAI["Google Gemini Flash (Multimodal OCR)"]
    end

    subgraph CloudState ["Cloud State & Multi-Device Sync"]
        Upstash["Upstash Serverless Redis (Lua Transaction Scripts)"]
    end

    Client -->|Biometric Signature| Privy
    Privy -->|Smart Account Session| SmartAccount
    SmartAccount -->|Gas-Sponsored UserOp| Pimlico
    Pimlico -->|Bundled Transaction| Network
    Network -->|payNettedDebt / Transfer| LedgerContract
    Client -->|Multi-Currency Conversion| Pyth
    Client -->|Receipt Image Upload| GoogleGenAI
    Client -->|Push / Pull / Sync| Upstash

🎭 Web3 $\to$ Web2 Abstraction Standard

MeshTab adheres to strict consumer fintech design principles — zero blockchain jargon leaks into the standard user experience:

Blockchain Mechanic	User-Facing Interface	Architectural Reality
`Gas Fees / Gwei`	Free / Sponsored	Pimlico Paymasters absorb 100% of Monad transaction fees.
`Private Keys / Seed Phrases`	Passkey (FaceID / TouchID)	Hardware WebAuthn enclave managed via Privy SDK.
`Contract Approval & Call`	1-Tap Settle Up	Batch `approve` + `payNettedDebt` UserOps in background.
`ERC-20 Token Transfers`	Digital US Dollars ($)	Agora AUSD represents 1:1 digital dollar values.
`Transaction Latency`	Instant Sub-Second Finality	Optimistic local updates backed by Monad's 10,000 TPS.
`Hex Wallet Addresses`	Member Profile & Avatar	0x addresses resolved dynamically from verified tab roster.

🏃 Quick Start

1. Clone & Install

git clone https://github.com/miracles2motion/Mesh-Tab.git
cd "Mesh-Tab"
npm install

2. Configure Environment

Copy .env.example to .env.local:

cp .env.example .env.local

Configure your credentials:

# 1. Upstash Redis (Tab sync & membership)
UPSTASH_REDIS_REST_URL="https://your-database.upstash.io"
UPSTASH_REDIS_REST_TOKEN="your_upstash_token"

# 2. Monad Testnet Web3 Config
NEXT_PUBLIC_MONAD_RPC_URL="https://testnet-rpc.monad.xyz"
NEXT_PUBLIC_AGORA_AUSD_ADDRESS="0xa9012a055bd4e0eDfF8Ce09f960291C09D5322dC"
NEXT_PUBLIC_AGORA_FAUCET_ADDRESS="0xd236c18D274E54FAccC3dd9DDA4b27965a73ee6C"
NEXT_PUBLIC_MESH_TAB_LEDGER_ADDRESS="0x54f02333ea8D80C175A1C8Bdb71ef709cF424C83"

# 3. Privy Authentication & Smart Wallets
NEXT_PUBLIC_PRIVY_APP_ID="your_privy_app_id"

# 4. Google Gemini Vision OCR (Receipt Scanning)
GEMINI_API_KEY="your_gemini_api_key"

Note: MeshTab includes complete local demo modes (sample and blank). You can explore the entire app, test debt netting, scan receipts, and run simulated settlements out-of-the-box without requiring live keys.

3. Run Development Server

npm run dev

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

4. Production Build

npm run build

Builds cleanly with Next.js 16 and React 19 with 0 TypeScript and compilation errors.

🎬 3-Minute Demo Walkthrough

Explore Landing (/):
- Interact with the Live Netting Visualizer to see how crisscrossing debts collapse into streamlined settlements.
- Click Try Demo Mode or Launch App.
Explore The Lisbon Benchmark (/tab/lisbon-24):
- Review the 4 group members ($1,499.10 total expenses across Aisha, Kemi, Ben, and You in EUR, GBP, and USD).
- Tap Run Netting to open the interactive SVG graph engine. Watch 9 multi-currency transfers collapse into just 3 direct AUSD payments ($391.54 net liquidity).
Multimodal Expense Logging (/tab/lisbon-24/expense/new):
- Receipt OCR: Tap the camera icon, upload a receipt, and watch Gemini Flash extract the amount and merchant in ~1 second.
- Voice Dictation: Tap the mic button and say: "I paid 80 dollars for rental car gas".
- Pyth FX: Select EUR or JPY to see real-time Pyth Hermes conversions into USD.
1-Click Settlement (/tab/lisbon-24):
- Tap Settle Up on your negative balance card.
- In Demo Mode, watch your balance recalculate and your debt clear to $0.00 instantly with confetti feedback.
- In Testnet Mode, approve and execute payNettedDebt on Monad Testnet gaslessly via Pimlico Paymaster.
Official Agora Faucet (/home):
- Connect your wallet on Testnet Mode and tap Add Funds $\to$ Confirm $10,000.00 Agora AUSD Allocation to fund your testnet account with instant testing liquidity directly from the official Agora Faucet on Monad.
Virtual Card & Yield Preview:
- Tap the Virtual Card banner on the Home dashboard to view instant card spendability controls.
- Watch the Agora APY Vault ticker on the tab page compound group savings at 4.80% APY.

🛣️ Production & Mainnet Roadmap

Phase 1: Metropolis Hackathon (Current) 🟢
- Instant FaceID passkeys & ERC-4337 smart accounts via Privy.
- Sub-second debt settlement on Monad Testnet (MeshTabAgoraLedger.sol).
- 100% sponsored gas fees powered by Pimlico Verifying Paymasters.
- Digital dollar liquidity via Agora AUSD.
- Mid-market foreign exchange rates via Pyth Network Hermes Oracles.
- Multimodal receipt OCR powered by Google Gemini Flash Vision.
- Resilient offline outbox queue with 2-way server synchronization.
Phase 2: Monad Mainnet & Live Yield (Q3 2026) 🟡
- Comprehensive security review and smart contract deployment on Monad Mainnet.
- Native Agora AUSD ERC-4626 Tokenized Yield Vault integration.
- Automated background netting settlement via Privy Server Wallets.
Phase 3: Consumer Scale & Banking Rails (Q4 2026) ⚪
- Seamless fiat on-ramps and bank cash-outs leveraging Privy Funding Rails.
- Virtual Visa Debit Card point-of-sale spendability via licensed BaaS partner (Stripe Issuing / Lithic).
- Native iOS & Android app store release with background peer sync.

📄 License

MIT License. Built for the Monad Metropolis 2026 Hackathon.

Name		Name	Last commit message	Last commit date
Product Documents		Product Documents
app		app
components		components
content		content
contracts		contracts
lib		lib
public		public
.env.example		.env.example
.gitignore		.gitignore
.npmrc		.npmrc
CLAUDE.md		CLAUDE.md
LICENSE		LICENSE
README.md		README.md
eslint.config.mjs		eslint.config.mjs
next.config.ts		next.config.ts
package-lock.json		package-lock.json
package.json		package.json
postcss.config.mjs		postcss.config.mjs
tsconfig.json		tsconfig.json

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MeshTab ⚡

💡 The Problem & The Solution

📊 Feature Maturity Matrix (Live vs. Prototype)

📜 Deployed Monad Testnet Contracts

🚀 Core Feature Breakdown

📐 System Architecture

🎭 Web3 $\to$ Web2 Abstraction Standard

🏃 Quick Start

1. Clone & Install

2. Configure Environment

3. Run Development Server

4. Production Build

🎬 3-Minute Demo Walkthrough

🛣️ Production & Mainnet Roadmap

📄 License

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MeshTab ⚡

💡 The Problem & The Solution

📊 Feature Maturity Matrix (Live vs. Prototype)

📜 Deployed Monad Testnet Contracts

🚀 Core Feature Breakdown

📐 System Architecture

🎭 Web3 $\to$ Web2 Abstraction Standard

🏃 Quick Start

1. Clone & Install

2. Configure Environment

3. Run Development Server

4. Production Build

🎬 3-Minute Demo Walkthrough

🛣️ Production & Mainnet Roadmap

📄 License

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