The Problem

Stablecoin depegs cause billions in losses. In 2022 TerraUSD collapsed overnight, wiping out billions in savings. Most people had no idea it was happening until it was too late.

The existing monitoring tools have a fundamental flaw — they rely on a single price source. One source can be wrong, manipulated, or just slow.

The Solution — Median of Medians

I built PegCheck, a stablecoin depeg monitoring API that aggregates from 6 independent sources:

CoinGecko

Coinbase

Binance

Kraken

DefiLlama

Chainlink price feeds

Then calculates a median across all of them — producing a single manipulation-resistant consensus price across 1,500+ data points.

The Chainlink Integration

Adding Chainlink took PegCheck to another level:

Price Feeds — USDT, USDC, USDS and TUSD price feeds on Ethereum Mainnet, added as a verified on-chain source to the median calculation.

Proof of Reserve — Chainlink PoR data for TUSD, giving verified on-chain reserve verification directly in the API response.

On-chain…