Fei Protocol

Fei Protocol issues FEI, a decentralized $1-pegged stablecoin backed by Protocol Controlled Value (PCV) — an algorithmic reserve of assets deployed across lending markets, staking protocols, and liquidity pools. The protocol also powers Tribe Turbo, a yield accelerator that lets users borrow FEI at 0% APR against collateral and supply it into ERC-4626 yield vaults, splitting revenue between users and the Tribe DAO. Development is no longer active; redemptions of FEI for DAI and TRIBE for protocol assets are available at tribedao.xyz.

Fei Protocol's revenue comes from several on-chain sources, all of which flow into a single treasury called the Protocol Controlled Value (PCV).

First, the treasury's assets are spread across different yield-bearing strategies through a standard PCV Deposit interface. These include:

• Lending on Compound (earning cToken interest)
• ETH staking via Lido (staking rewards)
• LP staking on Convex (CRV and CVX incentives)
• Liquity Stability Pool (accessed through B. Protocol)
• Rari Fuse lending pools (supply-side interest)

Each PCV Deposit has standard methods to add or withdraw funds. Rewards (like COMP, CRV, or CVX) can be collected by authorized roles — the PCV Controller or Guardian.

Second, the Peg Stability Module (PSM) charges small fees when users exchange DAI for FEI. Minting FEI (buying with DAI) costs 0 basis points (free), while redeeming FEI back to DAI costs 10 basis points (0.1%). These fees add to the PCV treasury. Any DAI sitting above a reserve threshold is automatically allocated into yield opportunities via allocateSurplus().

Third, Tribe Turbo lets users put up collateral (initially TRIBE, BAL, or gOHM) to borrow FEI at 0% APR from dedicated Fuse pools. They can then deposit that borrowed FEI into ERC-4626 yield vaults. A mechanism called slurp collects the interest earned on those vaults and splits the revenue between the user and Tribe DAO governance, according to a configurable rule (per safe, per collateral type, or a default split).

Fourth, when the protocol's collateralization ratio exceeds 100% (more assets than liabilities), the PCVEquityMinter creates new FEI based on the surplus equity times a governance-set APR. A Balancer Liquidity Bootstrapping Pool (LBP) auction then uses that FEI to buy TRIBE tokens, sending them to the treasury for ecosystem incentives.

Fifth, if the collateralization ratio drops below 100%, the TribeReserveStabilizer lets anyone mint FEI at $1 by burning newly issued TRIBE — acting as a backstop to keep the peg stable.

All PSM fees, PCV Deposit yields, and Turbo revenue shares ultimately accrue to the PCV treasury, supporting the FEI dollar peg and funding TRIBE buybacks. No fixed end-user APY exists; every rate depends on current market conditions and governance-set parameters.