TERRA/LUNA COLLAPSED this week — ~$40 BILLION of nominal value to approximately zero in five days, in the most instructive financial failure this archive has ever filed in real time. The mechanism, for the permanent record because it will be taught: TerraUSD (UST) was an ALGORITHMIC stablecoin — pegged to $1 not by reserves but by an arbitrage loop with its sister token LUNA (burn $1 of LUNA to mint 1 UST and vice versa), a design that works while LUNA has value and confidence holds, i.e., a stability mechanism made of the thing it’s meant to stabilize. The Anchor protocol paid ~20% “yield” on UST deposits (the demand engine; the file’s #110 vapor-median klaxon should have been audible from orbit), and when large UST withdrawals cracked the peg on May 7th, the arbitrage loop INVERTED into a doom spiral: UST redemptions minted LUNA hyperinflationarily (supply: ~350M to TRILLIONS of tokens in 72 hours), LUNA’s price fell 100%, the mechanism consumed itself, and a “Luna Foundation Guard” bitcoin reserve ($3B, deployed mid-crisis) vanished into the selling like sandbags into a dam breach. The file’s engineering read: this was a CONTROL SYSTEM with positive feedback under stress, no circuit breaker (#175), reserves committed AFTER the spiral (recovery dependencies inside the failure domain, #214), and a yield subsidy that was, mechanically, the customer-acquisition budget wearing an interest rate. The human read is grimmer: Anchor’s 20% drew life savings, not just degen capital — the r/TerraLuna suicide-hotline pins are the real postmortem (#225’s play-to-earn reckoning, compounding; the archive files them next to Mt. Gox #028, ten years and no regulatory perimeter later).
Contagion is now the watch item — Tether wobbled off-peg intraday (the reserve-backed giant restoring it, this time), and every leveraged fund holding UST/LUNA (Three Arrows’ positions are the whisper) is being re-marked by counterparties as I type. Winters kill by CONTAGION, not by first frost (#123’s file); fifteen-day cadence feels suddenly slow.
(Working AT a payments fintech through the sector’s worst fortnight is its own education: our treasury and compliance channels have never been busier, “boring rails” has never sounded more like a compliment, and every investor update now contains the word “runway” twice.)
TIL: reflexivity in mechanism design — any system where the stabilizer’s capacity derives from confidence in the system CANNOT stabilize a confidence crisis (banks solved this with lenders of last resort OUTSIDE the failure domain; algorithmic stablecoins re-derived the 1907 panic from first principles, minus the J.P. Morgan). Every whitepaper needs a section titled “what happens at negative feedback’s limit” — and the reviewer must be someone not paid in the token (#164, forever).