pegcheck

Real-time stablecoin monitoring dashboard with live peg data, multi-source price aggregation, and automated depeg alerts.

Features

• 19 stablecoins monitored every hour (USDT, USDC, USDS, USDe, PYUSD, FDUSD, RLUSD, TUSD, FRAX, GHO, crvUSD, LUSD, USDP, USDD, mkUSD, EURC, DOLA, alUSD, BOLD)
• 5–6 source median price (CoinGecko, Coinbase, Binance.US, Kraken, DefiLlama, Chainlink on-chain feeds)
• Deviation from peg in basis points stored to Supabase price_history
• Email alerts (Resend) and webhooks for depeg, caution, and recovery events
• On-chain depeg detection via StableGuard (Arbitrum Sepolia + Robinhood Chain testnet), broadcasting CCIP alerts to multiple destination chains in one tx
• Chainlink Proof of Reserve feeds for TUSD
• REST API: /api/depeg-status?coin={symbol} — multi-source real-time signal

Signal Levels

Deviation	Signal	Meaning
0–19 bps	STABLE	Within normal market spread
20–49 bps	WATCH	Elevated — monitor closely
50–99 bps	HEDGE	Reduce exposure 30–50%
100+ bps	EXIT	Rotate immediately

Backtest Accuracy

Analysis of 260,950 price snapshots stored in the price_history table across all tracked stablecoins.

Signal Tier Distribution

Tier	Threshold	Readings	% of Total
STABLE	< 20 bps	~248,000	~95.1%
WATCH	20–49 bps	~1,223	~0.47%
HEDGE / EXIT	≥ 50 bps	11,727	4.49%

Depeg Events (HEDGE threshold ≥ 50 bps)

37 distinct depeg events were identified across 6 coins (gap-clustered: readings >3 hours apart = separate event).

Coin	Events	Confirmed	Peak Deviation	Peak Price	Direction
alUSD (Alchemix)	1	1	444 bps	$0.9556	Below peg
EURC (Circle)	9	6	323 bps	$1.1665	Above peg (EUR/USD)
mkUSD (Prisma)	13	11	189 bps	$0.9811	Below peg
FRAX	5	5	143 bps	$0.9857	Below peg
DOLA (Inverse Finance)	1	1	94 bps	$0.9906	Below peg
LUSD (Liquity)	8	7	87 bps	$1.0087	Above peg
Total	37	31	—	—	—

Multi-Source Confirmation Rate: 83.8%

31 of 37 events were confirmed — defined as the signal persisting across two or more consecutive cron readings (≥ 1 hour apart), eliminating single-tick API anomalies. The remaining 16.2% were transient spikes that self-corrected within a single polling cycle.

Every confirmed reading already passes a 5-to-6 source median filter (CoinGecko, Coinbase, Binance.US, Kraken, DefiLlama, and on-chain Chainlink feeds for USDT/USDC/USDS/TUSD), so each row in price_history is itself a multi-source consensus price before event confirmation is applied.

Major blue-chip stablecoins (USDT, USDC, USDS, PYUSD, FDUSD) produced zero HEDGE-level events over the entire observed history, consistent with their strong collateralisation and market liquidity.

Methodology:

• deviation_bps = (price − peg) / peg × 10,000 (signed; negative = below peg). EURC uses live EUR/USD as its peg reference.
• Events are gap-clustered per coin with a 3-hour separation threshold.
• "Confirmed" = event spanned ≥ 2 consecutive polling cycles (~1 hour apart).

StableGuard Contracts

Autonomous cross-chain depeg protection powered by Chainlink Price Feeds, Automation, and CCIP. Each StableGuard instance monitors USDC and DAI prices, scores confidence across sources, and broadcasts alerts to all configured destination chains in a single performUpkeep tx.

Deployed Contracts

StableGuard (monitors + sends alerts)

Network	Address	Explorer
Arbitrum Sepolia	0xdD1B9120C26490C02EE6Cd1D7FdE47f7031201c6	Arbiscan
Robinhood Chain testnet	0xA00cbfF342F9009B23f08A0ED3c9918D2B5C86fa	Explorer

StableGuardReceiver (receives CCIP alerts)

Network	Address	Trusted sender
Ethereum Sepolia	0x235f049C2F38952CE228058b2a2A8B34AfD87Cb9	Arbitrum Sepolia StableGuard
Robinhood Chain testnet	0x6381383Ff70434A7681Bc329D89b3a7AC17129A8	Arbitrum Sepolia StableGuard

MockUSDC & MockVault (Ethereum Sepolia)

Contract	Address	Explorer
MockUSDC	0xcc502cE476D999f79b27bD1D45b7BD42564B05E7	Etherscan
MockVault	0x0B219D7045b879150b068EF86dDbDEAaBda6D1c4	Etherscan

MockVault pauser is set to the Ethereum Sepolia StableGuardReceiver — a CCIP depeg alert landing there can call pause() to block new deposits while withdrawals remain open.

CCIP Destinations (Arbitrum Sepolia StableGuard)

Destination	Chain selector	Receiver
Ethereum Sepolia	16015286601757825753	0x235f049C2F38952CE228058b2a2A8B34AfD87Cb9
Robinhood Chain testnet	2032988798112970440	0x6381383Ff70434A7681Bc329D89b3a7AC17129A8

Deploy & Wire

# Deploy StableGuard (4 constructor args — destinations added post-deploy)
npx hardhat run scripts/deploy-arbitrum.js --network arbitrumSepolia
npx hardhat run scripts/deploy-robinhood.js --network robinhoodChain

# Deploy receiver on Robinhood Chain
npx hardhat run scripts/deploy-receiver-robinhood.js --network robinhoodChain

# Fund + addDestination x2 + setTrustedSender on both receivers in one run
node scripts/wire-arbitrum-stableguard.js

# Prove multi-destination alert fires (ephemeral StableGuard + mock feed)
npx hardhat run scripts/trip-depeg.js --network arbitrumSepolia

API

GET /api/depeg-status?coin=USDT

Returns consensus price from up to 3 live sources (PegCheck/Chainlink, CoinGecko, CoinMarketCap), deviation in bps, signal tier, and confidence level (HIGH when ≥ 2 sources agree within 10 bps).

Development

npm install
npm run dev

Requires environment variables — see .env.example.

License

MIT