What is JustLend?

JUST Foundation
4 min readJan 26, 2022


I. Introduction

JustLend, a TRON-based decentralized lending protocol that provides a distributed and secure market where users can receive loans and earn interest at a low trading cost. On JustLend, each crypto market corresponds to a unique TRON asset such as TRX, TRC20 stablecoin (e.g. USDT), or other TRC20-based tokens, and entails an open and transparent ledger that records all transactions and historical interest rates. Users can supply tokens on JustLend and earn interests at low risk. Assets of DApps, institutions and exchanges can appreciate on JustLend.

II. JustLend Protocol


JustLend is a TRON-powered crypto market protocol aimed at establishing fund pools whose interest rates are determined by an algorithm based on the supply and demand of TRON assets. There are two roles within the protocol, namely suppliers and borrowers. Both of them interact directly with the protocol to earn or pay a floating interest rate. Features of JustLend Protocol:

  • Fund supply: JustLend adopts the idea of crypto market fund pools, with different underlying assets corresponding to their own markets.
  • Matching: Orders are matched by smart contracts automatically. There is no need for suppliers and borrowers to negotiate interest rates, loan terms, etc.
  • Interest accrual: Interest accrues as each block is generated on TRON (which takes around 3 seconds).
  • Lending: Lending is executed in real-time. Suppliers can enjoy interest without any action as long as they hold jToken.
  • Repayment: Borrow and repay as you go. Borrowing can be done as long as the collateral value * collateral factor > loan value + accumulated interest.
  • Supplying/borrowing interest rate: The floating interest rate is automatically calculated by JustLend smart contracts based on market supply and demand.
  • Liquidation: If the borrower’s collateral value falls below the liquidation threshold, JustLend smart contracts will automatically trigger liquidation.

2. Supplying Assets

On peer-to-peer platforms where borrowers are matched with lenders, a user’s asset is directly lent to another. By contrast, the JustLend protocol pools the supply of each user, which drives up liquidity and strikes a better monetary balance. Suppliers can withdraw their assets anytime without having to wait for a specific loan to expire, allowing JustLend much higher liquidity than their peer-to-peer counterparts. Assets supplied to a market are denoted as jToken (a TRC-20 token balance). Token holders can acquire the corresponding jToken by supplying and abiding by relevant rules to earn interest.

3. Borrowing Assets

If users (borrowers) wish to borrow an asset on JustLend, they need to first acquire jTokens as collateral through depositing tokens, and then borrow any available asset on the platform. Unlike peer-to-peer protocols, JustLend only asks borrowers to specify the borrowing asset with no other requirements such as the expiry date. Borrowing is executed in real-time, and its interest rate will be automatically adjusted based on the market’s supply and demand. Here’s an example: the interest rates for borrowing TRX and TRC20-USDT might be 2% and 5% respectively. Different assets have varying interest rates, which are automatically calculated according to the market’s supply and demand.

3.1 Collateral Value

Each market features a collateral factor ranging from 0 to 1, which represents the borrowing capacity for a certain amount of jToken (the collateral a borrower obtains by supplying the underlying asset). A lower collateral factor indicates an asset with lower liquidity, while a higher factor indicates higher liquidity. Borrowers are allowed to borrow up to, but not exceeding, their borrowing capacity so as to minimize the default risk for asset loaners.

3.2 Risks & Liquidation

If the value of a borrower’s borrowing outstanding exceeds the collateral factor that is deemed safe (their borrowing capacity), liquidation will be triggered automatically in JustLend smart contract to eliminate risks and ensure the over-repayment capacity for asset withdrawal and supply while safeguarding the depositors’ assets.

3.3 Primary Use Cases

JustLend protocol allows us to hold new assets seamlessly without having to sell tokens or go to various exchanges. This opens users, developers and traders to various forms of trading, such as:

  • Users can swap multiple TRC20 tokens in their possession in exchange for other TRC20 tokens.
  • We can short a certain token: borrow the token we wish to short from JustLend and sell on the exchange prior to its fall. This allows us to profit from the token’s loss.

3.4 Interest Rate Mechanics

While the interest of most traditional financial lending accrues by day, interest on JustLend is calculated based on the time of block generation on TRON (around 3 seconds). The interest rate of traditional financial lending remains fixed for the entire term of a loan. On the contrary, interest rates in the JustLend protocol change in real time according to the variation in market supply and demand, and the borrowing/supplying interest rates may vary from block to block in different markets. The JustLend protocol uses an algorithm to calculate the supplying interest rate for each asset. When borrowers’ demand for a crypto asset declines, the excessive tokens available for lending in the pool will bring about higher liquidity and a lower interest rate, thus encouraging borrowing; likewise, when the demand for borrowing an asset is high, the number of tokens available for lending drops, which will result in lower liquidity and a higher interest rate, thus attracting supplies