Developer docs

[Legacy] TrueFi DAO pools contracts

Below is a brief guide to TrueFi lending pool contracts.

For detailed questions, please reach out to the Discord #dev channel.

Lending pool addresses

Contract Name	Address
tfUSDC	0xA991356d261fbaF194463aF6DF8f0464F8f1c742
tfUSDT	0x6002b1dcB26E7B1AA797A17551C6F487923299d7
tfTUSD	​0x97cE06c3e3D027715b2d6C22e67D5096000072E5
tfBUSD	0x1Ed460D149D48FA7d91703bf4890F97220C09437

TrueFi DAO Pool contracts

• TrueFiPool2: lenders provide and withdraw liquidity to the pool, and can get lending pool details, such as pool value, pool token price, etc. from this contract

• TrueLender2: implements the lending strategy for the TrueFi pool, i.e. how loans are approved and funded

• LoanFactory2: deploys LoanTokens, which represent details of each loan on-chain

• TrueRatingAgencyV2: loan applications are rated and approved by TRU stakers

• TrueMultiFarm: lenders can stake lending pool tokens to earn TRU rewards (read more here)

• SAFU: handles bad debt in TrueFi lending pools (read more here)

TrueFiPool2 contract

The TrueFiPool2 contract is used by TrueFi DAO lending pools -- tfUSDC / tfUSDT / tfBUSD / tfTUSD. This contract enables accounts to pool tokens with the goal of earning yields on underlying tokens.

Contract Name	Address
TrueFiPool2	0x8d35372ea3e85c49a60f0a72edeff8629da3999a

Lending & Withdrawing methods

Method	Notes
join(uint256 amount)	Lends a certain amount of underlying tokens to the portfolio, and mints and transfers corresponding amount of ERC-20 lending pool ("LP") tokens to the lender.
liquidExit(uint256 amount)	Withdraws liquidity from the lending pool. Lender transfers pool tokens to pool and receives underlying token, but with a small penalty for liquidity as calculated by liquidExitPenalty() described below.

Determining pool values

Calculating LP token price

To calculate the price of the lending pool token ("LP token"), take poolValue() divided by totalSupply() .

Calculating pool APY

To calculate yield for a pool, one must calculate the weighted average of rates across each active loan in the pool and idle funds held in the pool.

pool_apy = SUM(loan_1_amount*loan_1_apy + ... + loan_n_amount*loan_n_value) / poolValue()

For an example of how this can be done via SQL, see this Dune query.

Method	Notes
poolValue()	Returns pool value in underlying token. This is the virtual price of the entire pool, including values for loan tokens and liquid underlying tokens held by the pool. Note: this assumes defaulted loans are worth their full value.
liquidValue()	Returns virtual value of liquid assets in the pool.
totalSupply()	Returns total number of pool LP tokens.
liquidRatio()	Ratio of liquid assets in the pool to the pool value, in basis points. For example, 4683 => 46.83%.
utilization()	Returns utilization in basis points. For example, 5316 => 53.16%. Calculated as 1 - liquidRatio().
liquidExitPenalty( uint256 amount )	Calculates lender will pay to withdraw liquid funds from the pool. This returns a proportion to be applied if liquidExit() is performed with the given amount of LP tokens. For example, when a pool is at ~75% utilization a small withdrawal would return liquidExitPenalty = ~0.9980, meaning that the lender would pay an exit penalty of ~0.20% (20 bps) to withdraw from the pool. For more detail on liquid exit and how the penalty is calculated, see here.
averageExitPenalty(uint256 from, uint256 to)	Internal function for calculating exit penalty.

Default handling

Read more about default handling in SAFU default handling

Method	Notes
liquidate(ILoanToken2 loan)	Calls SAFU function to liquidate bad debt. Liquidates a defaulted Loan, withdraws a portion of TRU from staking pool then tries to cover the loan with own funds, to compensate lending pool. Loan must be in defaulted state. If SAFU does not have enough funds, deficit is saved to be redeemed later.
reclaimDeficit(ILoanToken2 loan, uint256 amount)	After a defaulted loan's debt has been redeemed by the SAFU, the lending pool can reclaim call this function to redeem "deficiency claim" tokens for underlying tokens held in the SAFU.

TrueLender2 contract

Implements the lending strategy for the TrueFi pool, i.e. how loans are approved and funded.

Contract Name	Address
TrueLender2	0xa606dd423dF7dFb65Efe14ab66f5fDEBf62FF583

Method	Notes
fund()	When called, sends funds from the pool to the loan token contract. Pool receives and holds loan tokens. Must be called by the loan borrower.
loanIsCredible(uint256 yesVotes, uint256 noVotes)	Checks whether loan receives sufficient votes via stkTRU rating to be funded. Checks whether loan receives minimum ratio of yes to no votes and hits threshold of minimum votes set by owner.
reclaim(ILoanToken2 loanToken, bytes calldata data)	Redeems LoanTokens held by the pool for underlying funds held in the loan token. Loan token must be settled before calling this function.
reclaimDeficit(ILoanToken2 loan, uint256 amount)	After a defaulted loan's debt has been redeemed by the SAFU, the lending pool can reclaim call this function to redeem "deficiency claim" tokens for underlying tokens held in the SAFU.

Loan Token contracts

Loan tokens are created by LoanFactory2.

Contract Name	Address
LoanFactory2	0x69d844fB5928d0e7Bc530cC6325A88e53d6685BC

Each LoanToken has the following parameters:

• borrower(): address of borrower

• amount(): principal amount of fixed term loan

• term(): loan term in seconds

• apy(): loan APR in basis points (i.e. 971 = 9.71%)

• status(): returns loan's status, which progresses through the following states:

  • 0 --> Awaiting: Waiting for funding to meet capital requirements

  • 1 -->Funded: Capital requirements met, borrower can withdraw

  • 2 -->Withdrawn: Borrower withdraws money, loan waiting to be repaid

  • 3 -->Settled: Loan has been paid back in full with interest

  • 4 -->Defaulted: Loan has not been paid back in full

  • 5 -->Liquidated: Loan has Defaulted and stakers have been Liquidated

• canTransfer(): returns LoanTokens are non-transferable except for whitelisted addresses

• debt(): returns amount + interest. Note that this does not take into account whether the loan has been repaid.

• isRepaid(): returns boolean value, indicating whether a loan has been repaid in full.

• profit(): returns difference between debt() and amount(), the anticipated interest to be paid on the loan

Method	Notes
fund()	Transfers tokens to loan token contract from pool. Can be called only by lender contract. Sets status to Funded, start time, lender.
withdraw(address _beneficiary)	Borrower calls this function to withdraw funds to address provided. This sets the status of the loan to Withdrawn.
repayInFull(address _sender)	Function for borrower to repay all of the remaining loan balance. Borrower should use this to ensure full repayment.
_repay(address _sender, uint256 _amount)	Internal function for loan repayment. If _amount is sufficient, then this also settles the loan.
settle()	Moves loan to status = 'settled' if loan is fully repaid.
reclaim()	Function for borrower to reclaim any underlying currency stuck in the loan token contract. Only the borrower can call this function after the loan has been settled, defaulted, or liquidated.

Repaying loans to lending pools has two steps:

1. Borrower repays funds to loan token

2. reclaim() function is called on loan token, which burns the loan token and pays out fees to stkTRU.

TrueRatingAgencyV2

As described here, the TrueRatingAgencyV2 contract determines whether a loan request should be funded by TrueLender2.

Contract Name	Address
TrueRatingAgencyV2	0x05461334340568075bE35438b221A3a0D261Fb6b

stkTRU holders can vote yes() or no() on each loan. The TrueLender2 contract then checks to see if each loan satisfies threshold conditions in order to be funded.

stkTRU voters receive rewards in the form of TRU tokens for voting on loan requests. claimable() reward tokens are calculated as follows:

claimable() = (# TRU voted by user / # total TRU votes) * (Total TRU Reward), where

• Total TRU Reward = (Loan interest * TRU distribution factor * rewardMultiplier)

  • where Loan interest = (loan APR * term in days * principal) /365. Loan APR, term, and principal can be obtained from the respective loan token contract

  • rewardMultiplier can be found from the TrueRatingAgencyV2 contract

  • TRU distribution factor is calculated as remaining divided by amount from the RatingAgencyV2Distributor contract

TrueMultiFarm

As described here, lenders can stake LP tokens into the TrueMultiFarm contract to get TRU rewards.

Contract Name	Address
TrueMultiFarm	0xec6c3FD795D6e6f202825Ddb56E01b3c128b0b10
LinearTrueDistributor	0xc7AB606e551bebD69f7611CdA1Fc473f8E5b8f70

How to calculate lender emissions per day

• Total TRU emissions per day can be calculated using totalAmount() and duration() found on the distributor contract:

  • TRU distribution per day = (totalAmount/10^8) / (duration/(24*3600))

• To calculate farm rates for each token, use the formula below:

  • TRU rewards per farm per day = TRU distribution per day * getShare(IERC20 token) / shares() as described below

Method	Notes
stake(IERC20 token, uint256 amount)	Stake tokens to the farm. Upon staking, this will claim any claimable rewards.
unstake(IERC20 token, uint256 amount)	Remove staked tokens
claim(IERC20[] calldata tokens)	Claim TRU rewards
exit(IERC20[] calldata tokens)	Unstake amount and claim rewards
claimable(IERC20 token, address account)	Returns the claimable TRU reward for an account that is staking tokens.
shares()	Returns denominator for total farm rewards rate
getShare(IERC20 token)	Returns numerator for LP token's share of farm rewards