30 Seconds Can Be Forever for Stablecoins
A stablecoin depeg can have catastrophic consequences, even if it lasts only seconds. Most traders assume depegs are slow and gradual, but in reality, they can be sudden and devastating.
When a large sell order hits a liquidity pool on a decentralized exchange, the price of the stablecoin can drop below par in just 30 seconds. Arbitrage bots can detect this and exploit it by buying discounted stablecoins on one venue and redeeming or selling at par on another.
However, if the depeg persists past three blocks, the market transitions from a liquidity event to a confidence event, and the dynamics change fundamentally. The most consequential feature of a short depeg is not the price movement itself but the interaction between that movement and the oracle systems used by DeFi lending protocols.
These protocols rely on Chainlink price feeds, which update on chain according to specific rules. For major stablecoins, Chainlink's price feeds typically use a deviation threshold of 0.25 percent and a heartbeat of 3,600 seconds.