TESTNET
Markets
Trade
Lending Vaults
More
User Docs Developer Docs Sdk API Docs Help
Welcome to Polyester
Concepts
Overview
Creating an Account
Authentication Methods
Turnkey
Smart Wallets
Dashboard
Account Security
MFA
Asset Lifecycle
Supported Assets
Deposit Funds
Withdraw Funds
Transfer Funds
Inventory and Supply
Overview
Trading Fees
Base vs Quote
Lending Fees
Withdrawal Fees
Liquidation Fees
Rebates
Overview
On-chain Visibility
Overview
Supplying
Borrowing
Collateral
Interest
Liquidations
Overview
Trades
Candles
Order Book
Data Delivery
Notifications
Appearance
Localization
Sound Effects
Overview
Architecture
Benchmarks
Matching Engine
Settlement
Safeguards
Overview
Validators
Gas Abstraction
Layer-1 Benchmarks
Audits
Read Pre-compiles
Create Invite Code
Managing Links/Codes
Claiming Rewards
Auto-Convert Rewards
Overview
Create/Delete subaccounts
Permissions
Roles
Audit Logs
Unified Trading Account
Spot Trading
Order Types
Tools
Privacy
Custom Layouts
Overview
Asset Wrapping
Vaults
Zipper Security
What Is TEE?
  1. Lending
  2. /
  3. Overview

Overview

Lending on Polyester allows users to earn yield on assets they supply and borrow assets against collateral, all within the same unified exchange system used for funding and trading.

Lending operates through a dedicated smart contract and shares the same asset representations, account structure, and on-chain guarantees as trading.


How Lending Works

Lending on Polyester operates through overcollateralized supply pools.

Users can supply supported assets to lending pools to earn interest (denoted in APY). Other users may borrow from those pools by posting collateral that exceeds the value of the borrowed amount. Interest rates adjust dynamically based on pool utilization.


Unified Capital, Isolated Risk

Lending shares the same uAsset layer as trading, but risk remains isolated at the contract level. Assets supplied to lending are governed entirely by the lending protocol’s rules and cannot be accessed by trading systems unless explicitly permitted by the user.

This allows users to move capital between funding, trading, and lending without withdrawals or bridges, while preserving strict boundaries around risk and solvency.


Supplying Assets

When a user supplies assets on Polyester, they are contributing liquidity to a lending pool.

Supplied assets are backed 1:1 by the same on-chain inventory system that backs the rest of the exchange. Supplying assets does not change ownership guarantees or introduce rehypothecation.

Suppliers earn interest generated by borrowers who use those assets.


Borrowing Assets

Borrowing on Polyester requires collateral.

Collateral is designated from assets a user has already supplied to lending pools. Marking supplied assets as collateral does not remove them from the pool or stop them from earning interest; it only determines whether those assets can be used to secure borrowed positions and be included in liquidation events.

If collateral value falls below required thresholds, positions may be liquidated to protect lenders and the protocol.

Borrowed Amounts Must Be Overcollateralized
The value of the collateral must exceed the value of the loan to protect suppliers and protocol health. Collateral requirements and borrowing limits are enforced by smart contracts and updated in real time based on market conditions.

Risk and Liquidations

Lending risk on Polyester is managed through protocol-enforced liquidations.

Borrowing positions are continuously evaluated using a health factor that compares the value of collateral against outstanding debt. If a position falls below required thresholds, it becomes eligible for liquidation to protect lenders and maintain solvency.

Liquidations may occur either partially or fully. Large positions can be unwound in stages, while smaller or more severely undercollateralized positions may be liquidated in a single transaction. Liquidators repay debt in exchange for collateral at a protocol-defined discount, and any remaining collateral after repayment is returned to the user’s Funding Account. For more details on the costs of liquidations, see Liquidation Fees.

All liquidation rules and parameters are enforced by smart contracts, ensuring predictable behavior without discretionary intervention.


Transparency and Verifiability

Lending on Polyester is fully transparent at the protocol level.

Supplied balances, borrowed balances, utilization rates, and inventory backing are all observable on-chain. Solvency does not depend on trust in off-chain systems or opaque accounting.

While individual user positions are private, the system itself is continuously auditable.


Where to Learn More

For deeper details on Lending, see:

  • Lending Account - how lending balances are tracked
  • Supplying - how to supply assets and earn interest
  • Borrowing - how borrowing works and what limits apply
  • Collateral - how collateral is calculated and managed
  • Interest - how rates are determined
  • Liquidations - how risk is enforced and positions are closed
  • Fees - how fees are assigned for lending
Previous

On-chain Visibility

Next

Supplying

  • How Lending Works
  • Unified Capital, Isolated Risk
  • Supplying Assets
  • Borrowing Assets
  • Risk and Liquidations
  • Transparency and Verifiability
  • Where to Learn More