DeFi treasury vault with real USYC integration, USDC/EURC AMM swap, and cross-chain bridge on Arc Network
Landing page with yield calculator
Dashboard with flexible deposits and locked positions
Rewards page with Early Supporter Badge and referral program
Arc Treasury is a decentralized treasury vault that enables users to earn sustainable yield on USDC and EURC stablecoins. Built on Arc Network with real USYC integration via the Hashnote Teller contract.
USYC is the on-chain representation of Hashnote International Short Duration Yield Fund Ltd. (SDYF):
- Invests in reverse repo on U.S. Government backed securities
- Issued by Circle International Bermuda Limited (regulated by BMA)
- Instant on-chain subscribe/redeem via Teller contract
- ~4% APY from Fed rate returns with minimal risk
- MetaMask / External wallets — direct on-chain transactions via wagmi/viem
- Google OAuth (Circle wallet) — custodial wallet powered by Circle Developer Controlled Wallets, no browser extension needed
- Deposit USDC or EURC anytime
- Withdraw instantly with no lock-up period
- Earn real USYC APY (~3.99% after 5% platform fee)
Earn more Points by locking funds for fixed periods. APY is the same for all lock periods — lock bonus gives Points multiplier only:
| Lock Period | APY | Points Multiplier | Min Deposit |
|---|---|---|---|
| Flexible | ~3.99%* | 1x | $100 |
| 1 Month | ~3.99%* | 1.5x | $100 |
| 3 Months | ~3.99%* | 2x | $100 |
| 12 Months | ~3.99%* | 3x | $100 |
*APY is variable based on USYC T-Bill yield (~4.2%) minus 5% platform fee.
Early withdrawal available with 25% penalty on principal.
- On-chain AMM pool with 0.2% fee
- Add/remove liquidity with LP tokens
- Real-time EUR/USD exchange rate integration
- Bridge USDC between Ethereum Sepolia and Arc Network
- Powered by Circle CCTP V2 (native USDC, no wrapped tokens)
- Solana bridge support via Circle Bridge Kit
- Permanent points — never lost after withdrawal
- Formula: 1 point = $10 TVL × 1 day × lock multiplier
- Referral bonus: 10% of referral's points (lifetime)
- Early Supporter Badge: x1.2 points multiplier NFT
┌─────────────────────────────────────────────────┐
│ Frontend │
│ React + Vite + TailwindCSS + shadcn/ui │
│ │
│ ┌──────────────┐ ┌───────────────────┐ │
│ │ MetaMask │ │ Google OAuth │ │
│ │ wagmi/viem │ │ Circle Wallets │ │
│ └──────┬───────┘ └────────┬──────────┘ │
│ │ │ │
│ │ useUnifiedWallet() │ │
│ └──────────┬──────────┘ │
└────────────────────┼───────────────────────────────┘
│
┌────────────┼────────────┐
│ │ │
┌────▼────┐ ┌────▼────┐ ┌───▼────┐
│ Vault │ │ Swap │ │ Bridge │
│ api/ │ │ Pool │ │ CCTP │
│ vault.ts│ │ │ │ api/ │
└────┬────┘ └────┬────┘ │bridge.ts│
│ │ └───┬────┘
└────────────┼───────────┘
│
┌────────────▼────────────┐
│ Arc Testnet (5042002) │
│ USDC (native) · EURC │
│ TreasuryVault · Swap │
└─────────────────────────┘
- Deposit USDC/EURC → Funds go to TreasuryVault
- Operator converts → USDC → USYC via Hashnote Teller
- USYC earns yield → From US Treasury reverse repo (~4.2% APY)
- Withdraw anytime → USYC → USDC, receive principal + yield
| Contract | Address | Description |
|---|---|---|
| TreasuryVault (Proxy) | 0x17ca5232415430bC57F646A72fD15634807bF729 |
UUPS upgradeable vault (V14) |
| StablecoinSwap | 0x3a5964ce5cd8b09e55af9323a894e78bdd7f04bf |
USDC/EURC AMM, 0.2% fee |
| EURC | 0x742b2d045d430fe718b57046645ba33295914b69 |
EUR stablecoin, 6 decimals |
| EarlySupporterBadge | 0xb26a5b1d783646a7236ca956f2e954e002bf8d13 |
x1.2 points boost NFT |
| USYCOracle | 0xfe51166b831cd55737a1e1231a811ada0d7b3378 |
USYC NAV price oracle |
| USYC Teller | 0x9fdF14c5B14173D74C08Af27AebFf39240dC105A |
USDC/USYC conversion |
| USYC Token | 0xe9185F0c5F296Ed1797AaE4238D26CCaBEadb86C |
Hashnote yield token, 6 dec |
| Entitlements | 0xcc205224862c7641930c87679e98999d23c26113 |
USYC allowlist manager |
| Contract | Address | Notes |
|---|---|---|
| TokenMessenger | 0x8FE6B999Dc680CcFDD5Bf7EB0974218be2542DAA |
Sepolia domain=0, Arc domain=26 |
| MessageTransmitter | 0xE737e5cEBEEBa77EFE34D4aa090756590b1CE275 |
Same address on both chains |
| USDC (Sepolia) | 0x1c7D4B196Cb0C7B01d743Fbc6116a902379C7238 |
6 decimals |
| USDC (Arc) | 0x3600000000000000000000000000000000000000 |
Native gas token, 18 decimals |
| Layer | Technologies |
|---|---|
| Frontend | React 18, TypeScript, Vite, TailwindCSS, shadcn/ui |
| Web3 | wagmi v2, viem, Circle Developer Controlled Wallets |
| Bridge | Circle CCTP V2, Circle Bridge Kit (Solana) |
| Backend | Vercel Serverless Functions (Node.js) |
| Database | Supabase (PostgreSQL + Realtime) |
| Auth | Google OAuth via Supabase Auth |
| Blockchain | Arc Testnet (Chain ID: 5042002) |
| Yield | USYC via Hashnote Teller |
arc_treasury/
├── api/ # Vercel serverless endpoints
│ ├── _lib/ # Shared utilities (Circle SDK, Supabase)
│ ├── vault.ts # Deposit/withdraw/swap for Circle wallets
│ ├── bridge.ts # CCTP V2 bridge operations
│ ├── wallet.ts # Circle wallet management
│ ├── circle.ts # CCTP attestation proxy
│ ├── twitter.ts # Twitter OAuth for points boost
│ ├── referral.ts # Referral system
│ └── support/ # Support ticket system
├── src/
│ ├── pages/ # Route pages
│ ├── components/ # UI components
│ ├── hooks/ # React hooks (vault, swap, bridge, etc.)
│ ├── providers/ # Context providers (Circle wallet)
│ └── lib/ # Utilities, ABIs, constants
├── contracts/ # Solidity contracts + Hardhat scripts
└── supabase/ # Database migrations
- Node.js 20+
- npm
git clone https://github.com/vizzzix/arc_treasury.git
cd arc_treasury
npm installCopy .env.example and fill in your values:
cp .env.example .envRequired variables:
VITE_SUPABASE_URL/VITE_SUPABASE_ANON_KEY— Supabase projectCIRCLE_API_KEY— Circle Developer Controlled WalletsSUPABASE_SERVICE_ROLE_KEY— server-side Supabase access
npm run dev # Start dev server on http://localhost:8080
npm run build # Production build
npm run preview # Preview production buildnpm test # Run 203 unit tests (vitest)
npm run test:e2e # Run 29 E2E tests (Playwright)
npm run test:e2e:ui # E2E with interactive UITests cover:
- Bridge API endpoints (approve, burn, claim, tx-status)
- Vault logic (deposit, withdraw, swap, liquidity)
- Swap pool calculations (slippage, min output)
- Locked positions (yield, mapping, early withdraw)
- E2E smoke tests for all pages
- JWT authentication on all financial API endpoints (vault, bridge, wallet)
- Wallet ownership verification — users can only operate on their own wallets
- Rate limiting with Upstash Redis (sliding window) on all endpoints
- Input validation — UUID, address, txHash format checks
- CORS whitelist — only allowed origins
- Security headers — X-Frame-Options, X-Content-Type-Options, Referrer-Policy
- Sentry error monitoring with source map upload
- Non-custodial for MetaMask users
- Circle wallet keys managed by Circle's HSM infrastructure
- Server-side transaction execution for Circle wallets (no private keys in browser)
- Vault whitelisted by Circle/Hashnote for USYC operations
- Real USYC integration (not simulated)
- On-chain NAV oracle for price feeds
Testnet Notice: This is a testnet deployment. Use only test tokens.
- Website: https://arctreasury.biz
- Litepaper: https://arctreasury.biz/litepaper
- FAQ: https://arctreasury.biz/faq
- Explorer: https://testnet.arcscan.app
- Circle Faucet: https://faucet.circle.com/
- Arc Network: https://arc.network
MIT License - Arc Treasury 2025-2026