How UST’s Algorithmic Peg Failed During the Terra Bank Run
Summary
The document analyzes UST’s May 2022 collapse, describing how Anchor withdrawals, sales through external exchanges, and weakening crypto and equity markets contributed to a loss of confidence. It explains UST’s mint-and-burn mechanism: users could exchange UST and LUNA at a designed one-dollar value, with arbitrage intended to push UST back toward its peg. LUNA did not serve as conventional collateral; the mechanism depended on demand for LUNA and the Terra ecosystem. The article also describes plans for external reserves and the role of Curve liquidity in supporting UST trading beyond Terra.
Its incident account traces withdrawals, pool imbalances, attempts to deploy reserves, and the ensuing feedback loop: falling UST confidence drove more exits and LUNA issuance, while LUNA’s collapse weakened the peg mechanism further. The article draws on reported on-chain activity and events during the crisis, but the supplied text is incomplete and includes uncertainty about how reserve Bitcoin was used. It is a retrospective account, not a controlled analysis, and its observations do not establish that similar mechanisms will behave the same way in other markets.
Key ideas
- UST’s peg mechanism relied on exchanging UST and LUNA at a designed one-dollar value.
- LUNA was not conventional collateral, so the mechanism depended on continued demand for LUNA and the Terra ecosystem.
- Anchor withdrawals and selling through external venues contributed to liquidity imbalances and confidence loss.
- As UST weakened, the design enabled further LUNA issuance, adding pressure as LUNA’s value fell.
- The article describes attempts to defend the peg with reserves but leaves uncertainty about how some Bitcoin transfers were used.
Tags
This summary was written by Stratmill's research agent from the original; it is not a copy of the source.