Matrixdock Pool

Overview

TProtocol works with Matrixdock, a digital assets platform that provides institutional and accredited investors with transparent access to tokenized real-world assets (RWA) with an immutable record of ownership, daily Proof-of-Reserve and full bankruptcy remoteness, to issue our first RWA lending pool.

This pool allows Matrixdock (or other whitelisted entities) to deposit STBT, permissioned T-Bill token, as collateral to borrow USDC from users. This pool is highly customized to ensure the highest capital efficiency, best user experience and asset safety.

STBT

STBT is issued by Matrixdock, a digital asset platform that provides access to Real World Assets (RWA) through tokenization. It is a brand fully owned by Matrixport, an all-in-one crypto financial service platform. BlockSec and Zellic.io, two leading security firms, have both published the security audit report on the STBT smart contract.

STBT is a stablecoin which rebases once a day.

To ensure asset transparency, STBT has partnered with the leading decentralized oracle Chainlink to conduct Proof of Reserve (PoR) on daily basis.

Users can easily keep track of the underlying assets which support the value STBT in real time with this link.

Lending

Users can deposit USDC to Matrixdock Pool to get access safe real yield over-collateralized by T-Bill tokens. The estimated APY for USDC lender will be around 5% given the current macroeconomic environment.

Borrowing

Borrowing is available for all the users who have STBT. To get access to STBT, users need to complete KYC-AML done by Matrixport.

Customized Interest Rate Model

Since T-Bill is almost the safest assets in the world, TProtocol designs an innovative interest rate model for Matrixdock Pool to maximize the capital efficiency and pass as much yield to users as possible.

The core idea is that the lending rate will not exceed the APY of STBT. Our pool will read the current APY of STBT and use it as the upper bound of lending rate. This ensures higher utilization rate of USDC hence higher APY for USDC lender. The LTV for STBT is set at 99%. Since Matrixdock will borrow as much USDC as possible, there will be no large amount of idle USDC sitting in the pool and diluting the lending rate.

For instance, if the LTV is only 90% and STBT depositors deposit $100M of STBT and there is $100M liquidity of USDC. STBT depositors can only borrow $90M USDC due to 90% LTV. The maximal borrowing rate STBT depositors can pay will not go beyond the APY of STBT. Otherwise, the borrowing cost will be higher than the APY of STBT and STBT depositors will be losing money. Therefore, only 90% of STBT APY will be passed to users. If STBT is 5%, then users will get around 4.5% without considering the interest spread TProtocol charges. But in our model, STBT depositors can borrow almost $100M and pay almost 5% to users.

Loan Recall Mechanism

In traditional lending protocol, there usually are some idle funds sitting in the protocol as liquidity. These idle funds dilute the APY lenders earn. Our loan recall mechanism and high LTV of STBT fix this, but one issue high capital utilization rate brings is liquidity. To solve this, we propose an innovative loan recall mechanism.

The core idea is that unlike traditional lending protocols, users can recall loan collateralized by STBT whenever they want so that liquidity is ensured while capital efficiency is high. We offer two types of loan recall:

1. TProtocol liquidates the STBT from USDC borrowers by selling STBT into STBT-3CRV pool and returns USDC to users. This is more suitable for small amount as this might incur slippage.

2. TProtocol liquidates the STBT from USDC borrowers by redeeming STBT for USDC. This will have no slippage but have a fee of 0.1% and require around 3 business days to process the bank transfer and onramp.

As the borrowing cost will not exceed the APY of STBT, USDC borrowers' net balance on TProtocol will always be positive. Therefore, there will not be any liquidation triggered by net balance dropping below minimal threshold.

The recall mechanism will be applied to the address which has the highest USDC debt.

rUSTP and iUSTP

When users deposit USDC in the pools, promissory note tokens rUSTP will be minted to users to demonstrate they have deposited USDC into the pools. rUSTP is a rebasing token pegged at $1.

When users want to redeem the investment, rUSTP will be burnt and USDC will be returned. As the interest accrues, the amount of rUSTP will increase over time.

Users can convert rUSTP to iUSTP at internal exchange rate. The relation between rUSTP and iUSTP is similar to the relation between stETH and wstETH.

The price of iUSTP will start from $1. As interest accrues into iUSTP, the price of iUSTP will increase over time. This price will be tracked in our protocol and be used for the conversion between iUSTP and rUSTP.

USTP

Unlike rUSTP, USTP is a stablecoin without any rebasing mechanism. Users can convert between rUSTP and USTP at 1 to 1 ratio. USTP is mainly used for liquidity providing and cross chain and is not interest bearing.

Minting: To mint USTP, users need to deposit rUSTP into convertor. And convertor will mint USTP to users at 1 to 1 ratio. For instance, one user who deposits 100 rUSTP into convertor will receive 100 USTP.

Redemption: Users can also redeem USTP to rUSTP also at 1 to 1 ratio. For instance, one user who deposits 100 USTP into convertor will receive 100 rUSTP. By converting USTP to rUSTP, users will start to earn interests from the lending pool.

Pegging Mechanism: As stablecoin, USTP should be pegged at $1. This is achieved by arbitrage. If USTP is higher than $1, users can mint rUSTP with USDC and convert rUSTP to USTP and sell USTP for USDC to secure risk-free profit. This will bring the price of USTP down to $1. If USTP is lower than $1, users can buy USTP with USDC and convert USTP to rUSTP and redeem rUSTP for USDC to secure risk-free profit. This will bring the price of USTP back to $1.

Liquidity pool for USTP will be incentivized. As USTP is stablecoin without rebasing, highly efficient stableswap could be used to ensure minimal slippage. When users swap rUSTP or iUSTP for other tokens, iUSTP or rUSTP will be first converted to USTP and finish the swapping with USTP liquidity pool. The advantage of incentivizing liquidity on USTP instead of iUSTP or rUSTP is that USTP is a stablecoin and highly efferent stableswap can be applied to ensure low slippage. And the conversion between rUSTP and iUSTP and USTP relies on the internal price which incur zero slippage. Therefore, we are able to ensure low slippage when swapping iUSTP and rUSTP.

Multichain Solution

Matrixdock Pool will be first deployed on ETH mainnet and then major L2 including Arbitrum and Optimism. There will be native iUSTP and USTP on each chain. Cross chain functionality will be supported by a third party bridge by providing liquidity for USTP. As USTP is stablecoin, TProtocol can easily incentivize USTP_CHAIN_1-USTP_CHAIN_2 pair. After users get the native USTP on destination chain, users can convert USTP to iUSTP to earn interest.