Architecture

V1 Vaults

Unagii Vaults V1 is an Ethereum-based protocol that enables users to passively earn from automated yield farming by depositing single crypto assets into the Vaults executing a specific Strategy in a gas-efficient environment. Unagii integrates with third-party DeFi protocols (i.e. AMMs and lending platforms), enabling support for a wide selection of strategies that are deemed safe and valuable to users.

Unagii Vaults V1 Architecture

Name	Description
admin	Admin refers to the Unagii team, managed by a 2 out of 3 team member Gnosis multisig. Admin members are able to set and approve strategies, and execute the deposit invest harvest skim withdraw exit functions.
bots	These are Externally Owned Accounts (EOA) that are set to automate transactions at specific time periods to the Controller contract.
controller	The main Unagii governance contract. Only the Admin and Bots are authorized to trigger transactions on the Controller.
defi	DeFi is the acronym for Decentralized Finance, a term describing a variety of blockchain-based financial protocols and applications.
deposit	The function to transfer user funds into Strategy.
exit	The function to claim and sell down rewards, then return all funds in the associated Strategy back into the Vault.
gas token	This is the contract that allows Unagii to tokenize gas on Ethereum. Unagii will store gas when it is cheap to do so, and spend the Gas Token when deployment and transaction costs are high.
gas relayer	This enables the Bots to spend the Gas Token on a transaction that cuts transaction fees.
harvest	The function to claim and sell down rewards into the most premium deposit token, then re-investing the token back into the vault, thereby compounding rewards.
invest	Calls the Deposit function to transfer tokens from the Vault into the Strategy.
skim	The function to update user balances according to the asset balance in the Strategy. It can only be called when the asset balance is more than the debt balance within the Strategy.
strategy	Strategy determines how yield is generated and accrued. Each DeFi protocol has different sets of strategies. Unagii has curated a bank of whitelisted strategies handpicked by the team that will give users the best performing yields on their tokens.
time lock	All new strategy contracts to be launched will be deployed behind a 24 hour time lock. It is currently managed by admin. The time lock will need to be called in order for new strategies to be approved. Users will be able to verify all of such events on-chain.
withdraw	The function to withdraw tokens from the Strategy back into the Vault.

V2 Vaults

Unagii Vaults V2 is the next iteration of the protocol with a slightly different architecture:

• Vaults are upgradable by default as the Unagii Token contracts and the Vault contracts are separated, making it similar in design with Curve token and Curve pool contract

• Smart contracts can interact (deposit/withdraw) from the vaults, which allows any developer to integrate with Unagii Vaults V2 (there is a block delay)

• Vaults are protected from flash loan attacks as Unagii token tracks the lastest block number of the caller

• Protected from sandwich attack on harvest as profit is vested over a period of time (6 hours for now)

• Vaults are able to invest in multiple strategies, allowing the protocol to maximize returns by optimizing the allocation of funds to each strategy

Unagii Vaults V2 Architecture

Unagii Token

Name	Description
mint	mint Unagii shares when user deposits.
burn	burn Unagii shares when user withdraws.
setMinter	set minter to Vault. this makes Unagii V2 upgradable. (only called by TimeLock).

Vault

Name	Description
deposit	user deposit token (DAI, USDC, USDT, ETH, WBTC), receives Unagii token in return.
withdraw	user withdraws token (DAI, USDC, USDT, ETH, WBTC), Unagii token is burnt.
setFundManager	set FundManager used to upgrade FundManager contract (only called by TimeLock).
borrow	borrow user funds from Vault (only FundManager can call).
repay	repay borrowed funds (only FundManager can call).
report	report profit back to Vault.

Fund Manager

Name	Description
setVault	set Vault used to upgrade Vault contract (only TimeLock can call).
approveStrategy	approve new strategy (only TimeLock can call).
addStrategyToQueue	activate strategy (only approved strategy can be activated).
removeStrategyFromQueue	deactivate strategy.
setQueue	reorder activate strategies (order determines which strategy to withdraw from first).
borrowFromVault	borrow user funds from Vault.
repayVault	repay user funds to Vault.
reportToVault	call report on Vault.
withdraw	withdraw user funds from FundManager and activate strategies, back into Vault.

Strategy

Name	Description
borrow	borrow user funds from FundManager.
repay	repay user funds to FundManager.
report	report profit back to FundManager.
withdraw	withdraw user funds back into FundManager.
deposit	borrow from FundManager and invest into external DeFi.
claimRewards / skim / harvest	claim profit.

V3 Vaults

Unagii Vaults V3 further iterate upon the protocol with the following changes:

• Implements the ERC-4626 standard for compatibility with other DeFi protocols

• Gas cost optimizations for users and operators

• Upgradable Swap contract allows us to choose the best AMM exchange rates for yield -> vault tokens in response to changing market conditions

Unagii Vault V3 Architecture

Vault

Name	Description
deposit / mint	deposit asset token (USDC, ETH, etc) in exchange for Unagii vault tokens
withdraw / redeem	exchange Unagii vault tokens for asset token (USDC, ETH, etc)
addStrategy	adds a new strategy to strategy queue
removeStrategy	withdraws all assets from strategy to Vault and removes it from strategy queue
harvest / harvestAll	claim profit from strategies
report / reportAll	re-balance assets within strategies
collectFromStrategy	manually withdraws assets from strategy

Strategy

Name	Description
harvest	claim profit from DeFi
invest	deposit assets into DeFi
withdraw	sends assets back to vault
setSwap	set swap contract used (if necessary)

Swap

Name	Description
setRoute	choose AMM to swap token pair with (e.g. Uniswap, Sushiswap)
swapTokens	swap tokens along the assigned best route

Smart Contracts