Yield Strategy

The strategy receives borrowed stablecoins and deploys them to earn yield. Profit is the spread between yield earned and borrow cost.

Active Strategy (LlamaLend + StakeDAO)

Active vaults (wbtc-llamalend, wsteth-llamalend) borrow crvUSD via LlamaLend and deploy into the Curve crvUSD/USDT pool, with LP tokens staked in StakeDAO for boosted CRV rewards.

Flow

  1. Borrow crvUSD from the LlamaLend loan manager.
  2. Provide liquidity in the Curve crvUSD/USDT pool.
  3. Stake LP in StakeDAO (OnlyBoost gauge).
  4. Harvest CRV, swap CRV → crvUSD, and compound.

Strategy Economics

Net carry on deposited collateral is approximately:

implied yield ≈ LTV × (StakeDAO yield APR − LlamaLend borrow APY)
  • Yield APR: Curve trading fees + CRV emissions at StakeDAO boost, net of protocol fee. Live value from /api/stakedao-apr.
  • Borrow cost: LlamaLend crvUSD market APY from /api/llamalend.
  • LTV: Current loan-to-value from the loan manager (target managed by vault rebalancing).

While TVL is small, measured historical APR from snapshots can be noisy. The stats page shows implied carry from live on-chain inputs for testing vaults.

Legacy Strategy (Aave + RAAC pmUSD)

Legacy vaults (wbtc-pmusd, wsteth-pmusd, xaut-pmusd) use PmUsdCrvUsdStrategy. They are withdraw-only and no longer accept new deposits.

Legacy flow

  1. Borrow USDT from the Aave V3 loan manager.
  2. Swap USDT → crvUSD (Curve).
  3. Add single-sided liquidity into the RAAC pmUSD/crvUSD pool.
  4. Stake LP in StakeDAO reward vault.
  5. Harvest CRV, swap CRV → crvUSD, and compound.

Strategy Interface (Vault-Controlled)

  • deposit(uint256)
  • withdraw(uint256)
  • withdrawAll()
  • harvest()
  • balanceOf()
  • pendingRewards()
  • emergencyWithdraw()

Strategy admin methods are callable by the vault, not by arbitrary users.

Slippage and Price Safety

  • Strategy-level slippage has explicit caps.
  • Stablecoin swap paths use oracle-backed floor logic for safety checks.
  • Virtual price checks protect against manipulated LP valuation drift.

Operational Notes

  • Harvest is permissionless at vault level: users/keepers can trigger compounding for everyone via harvestYield().
  • Strategy value is reported in debt-asset terms and converted to collateral-equivalent value for vault accounting.
  • Strategy/debt ratio: the vault tracks strategy balance vs debt balance around 100%. Rebalancing triggers when LTV drifts outside the deadband; ratio history is on the stats page.
  • Emergency path exists to unwind quickly if external integrations degrade.
  • Operator monitor: /monitor surfaces liquidity, health flags, and idle/emergency controls for strategists.

Why This Design

  • Keep collateral side conservative in the lending layer.
  • Isolate yield logic in modular strategy contracts.
  • Allow clear accounting between direct collateral and debt-side deployed value.
  • Swap loan manager and strategy families via new vault deployments without changing the ERC-4626 interface.