What is USYC Protocol Labs?
USYC Protocol Labs builds DeFi infrastructure on Arc Network, making Treasury yields accessible to everyone through simple, secure products.
What is USYC?
Circle's yield-bearing stablecoin backed by US Treasury Bills. It provides ~3-5% APY while maintaining stability.
What is Arc Network?
Circle's new Layer 1 blockchain designed specifically for stablecoins and Real World Assets (RWA).
Who is Circle?
The company behind USDC, the 2nd largest stablecoin with $25B+ in circulation.
Who is Hashnote?
Circle's partner that manages USYC and the underlying Treasury Bill investments.
Core Products
Getting Started
USYC Protocol provides two core primitives for programmable Treasury yields on Arc Network.
Yield Vault
ERC-4626 compliant vault for automated Treasury yield. Deposit USDC, earn ~3-5% APY.
Payment Streaming
Real-time payment flows for salaries, subscriptions, and vesting schedules.
Quick Start
Connect to Arc Network
Add Arc Testnet to your wallet (Chain ID: 462050)
Get Testnet Tokens
Use the faucet to get ARC and USYC tokens
Start Building
Integrate with our smart contracts using ethers.js or viem
Fees
Protocol Fees (USYC Protocol Labs)
Yield Vault Fees
Payment Stream Fees
Example: $10,000 USDC deposited for 1 year
Smart Contracts
USYCVault.solERC-4626USYC Yield Vault
The main vault contract for depositing USDC and earning Treasury yields.
Key Functions
deposit()Deposit USDC and receive vault shares. Starts earning immediately.
withdraw()Withdraw USDC plus accumulated yield at any time.
getYield()View current accumulated yield without withdrawing.
Deployed Contracts (Arc Testnet)
0x2f685b5Ef138Ac54F4CB1155A9C5922c5A58eD250x1fcb750413067Ba96Ea80B018b304226AB7365C60x9f3856dF5CE0797aEe7FaE3E13794d4d52f9eB400x8B412f7cAfA72482BE146268C4AD57231D8282cF0xe9185F0c5F296Ed1797AaE4238D26CCaBEadb86CAPI Reference
Integration with ethers.js
Integration with viem
USYC APIs (Hashnote)
Public APIs from Hashnote for USYC price data. No authentication required.
Mainnet Endpoints
| Get current price | https://usyc.hashnote.com/api/price |
| Historical data | https://usyc.hashnote.com/api/price-reports |
Testnet Endpoints
| Get current price | https://usyc.dev.hashnote.com/api/price |
| Historical data | https://usyc.dev.hashnote.com/api/price-reports |
StableFX Integration
What is StableFX?
StableFX is Circle's institutional-grade stablecoin FX engine built on Arc Network. It enables instant conversion between stablecoins (EURC ↔ USDC) with 24/7 settlement and sub-second finality.
How USYC Protocol Labs uses StableFX
For Deposits (Vault)
For Payment Streams
For Withdrawals
Supported Currencies
USDC
US Dollar
EURC
Euro
More
Coming soon
Official Links
Security
Smart Contract Audits
All contracts audited by leading security firms before mainnet deployment.
Upgradeable Proxies
UUPS proxy pattern with 24-hour timelock for transparent upgrades.
Access Controls
Role-based permissions with multi-sig requirements for admin functions.
Treasury Backing
USYC is 100% backed by US Treasury Bills, managed by regulated custodians.
Bug Bounty Program
Found a vulnerability? Report it responsibly and earn rewards up to $50,000.
Report a BugFAQ
Ready to Build?
Start integrating Treasury yields into your application today.