Sperax USD: Yield-Automating Stablecoin on Arbitrum

2026-07-16

SperaxUSD (USDs) is a 100% collateral-backed stablecoin and yield-automator on Arbitrum. Users mint USDs by depositing collateral, which is then automatically deployed into DeFi strategies to generate yield. Rather than requiring users to manually harvest and reinvest, USDs holders passively receive yield through automatic rebasing: their token balance increases each day without any action required.

Revenue comes from two streams. The protocol retains 30% of yield harvested from the collateral basket, using it to buy back SPA governance tokens on the open market. USDs holders receive the remaining 70% through daily rebases. Additionally, a small mint and redeem fee is charged on each USDs issuance and redemption, all of which goes to the protocol. All-time revenue stands at $19,900, with current activity near zero: the protocol has wound down significantly from its peak usage period.

The adapter reads YieldHarvested events from the Sperax Vault and Dripper contracts on Arbitrum. Gross yield is extracted from each harvest, and the 30/70 split is applied. Mint and redeem events are tracked separately. The rebase mechanism means that supply-side revenue is delivered through token quantity changes rather than explicit transfers, which required different accounting logic than a standard DeFi yield protocol. The 30% SPA buyback routing was also tracked separately as holder revenue distinct from treasury revenue.

Website: sperax.io · Twitter: @SperaxUSD