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PredMart Protocol Overview

PredMart is a non-custodial lending protocol purpose-built for the prediction market ecosystem. It enables users to deposit their Polymarket outcome shares as collateral and borrow USDC against them — unlocking liquidity from positions that would otherwise sit idle until a market resolves.

The borrowed USDC can be used for any purpose, but the most powerful use case is leveraged trading on prediction markets: borrow USDC against your existing shares, use that USDC to buy even more shares on Polymarket, and amplify your exposure to outcomes you believe in.

On the other side of the protocol, lenders supply USDC to the lending pool and earn yield generated from borrower interest payments. The protocol operates as a two-sided marketplace: borrowers pay interest for the liquidity they access, and lenders earn a share of that interest for providing it.

The Problem PredMart Solves​

Prediction markets like Polymarket allow users to trade on the outcomes of real-world events — elections, sports, economic indicators, and more. When you buy shares on Polymarket, those shares represent a position in a particular outcome. If your prediction is correct, each share pays out $1.00. If it's wrong, the share becomes worthless.

However, there is a significant limitation in this ecosystem: your capital is locked. Once you purchase prediction market shares, your USDC is tied up in those positions until the market resolves. This creates several problems:

  1. Capital inefficiency: Traders who hold high-conviction positions cannot deploy that capital elsewhere. A trader who owns 10,000 shares of an outcome priced at $0.70 has $7,000 worth of exposure but cannot use any of that value until the market settles — which could be weeks or months away.

  2. No leverage: Unlike traditional financial markets where traders can use margin to amplify their positions, prediction market traders are limited to 1x exposure. If you have $1,000 in USDC, you can only buy $1,000 worth of shares. There is no native mechanism to take a leveraged position.

  3. Opportunity cost: Markets move. While your capital is locked in one position, new opportunities emerge in other markets. Without the ability to borrow against existing positions, traders must choose between holding their current positions and pursuing new ones.

  4. Idle assets for passive holders: Users who hold prediction market shares for the long term receive no yield on those holdings while they wait for resolution. The shares simply sit in their wallet, generating no additional return.

PredMart solves all of these problems by creating a lending market around prediction market shares. By accepting Polymarket shares as collateral, PredMart transforms illiquid prediction market positions into productive assets that can generate additional capital and yield.

How PredMart Works​

The protocol consists of two primary participant roles and a smart contract system that mediates between them:

Lenders (USDC Suppliers)​

Lenders deposit USDC into PredMart's lending pool. In return, they receive pUSDC — vault shares that represent their proportional ownership of the pool. As borrowers pay interest on their loans, the value of each pUSDC share increases over time. Lenders can redeem their pUSDC for the underlying USDC plus accrued interest at any time, subject to available liquidity in the pool.

The lending pool is implemented as an ERC-4626 tokenized vault — an industry-standard Ethereum specification for yield-bearing vaults. This means pUSDC is a standard ERC-20 token that is composable with other DeFi protocols and can be transferred between wallets.

Borrowers (Prediction Market Traders)​

Borrowers deposit their Polymarket outcome shares (ERC-1155 tokens from Polymarket's Conditional Token Framework) into PredMart's lending pool contract as collateral. Once collateral is deposited, the borrower can take out a USDC loan up to a limit determined by the Loan-to-Value (LTV) ratio for their collateral.

The LTV ratio is not a fixed number — it varies based on the current market price of the collateral shares. Shares trading at higher prices (closer to $1.00) receive higher LTV ratios because they are considered less risky. Shares trading at lower prices receive lower LTV ratios. This dynamic LTV system is one of PredMart's key innovations, implemented through a 7-anchor interpolation curve defined on-chain.

Borrowers pay interest on their outstanding loans. The interest rate is determined algorithmically based on the utilization rate of the pool — the percentage of the pool's USDC that is currently lent out. Higher utilization means higher interest rates, which incentivizes more lenders to supply USDC and encourages borrowers to repay their loans.

The Smart Contract​

PredMart's core smart contract — the PredmartLendingPool — is deployed on the Polygon blockchain. It handles all critical operations: accepting deposits from lenders, managing collateral from borrowers, executing borrows, processing repayments, accruing interest, and performing liquidations.

The contract is non-custodial, meaning PredMart (the team) cannot access, move, or seize user funds. All operations are governed by immutable smart contract logic. The only exception is administrative functions (such as updating the oracle address or adjusting risk parameters), which are protected by a timelock mechanism that gives users advance notice of any changes.

Key Features​

Non-Custodial Design​

PredMart never takes custody of your funds. When you deposit USDC as a lender, it goes directly into the smart contract — not into a company wallet. When you deposit collateral as a borrower, the shares are held by the smart contract, not by PredMart. All interactions are peer-to-contract: you interact directly with the blockchain, and the smart contract enforces all rules.

Dynamic LTV Curve​

Unlike protocols that assign a single, fixed LTV to an asset, PredMart uses a 7-point interpolation curve that adjusts the LTV based on the current price of the collateral. This is critically important for prediction market shares because their risk profile changes dramatically with price:

  • A share trading at $0.90 is relatively safe — it only needs to maintain its value, and the market is strongly indicating this outcome is likely. PredMart assigns a higher LTV.
  • A share trading at $0.20 is much riskier — the market considers this outcome unlikely, and the price could drop further. PredMart assigns a lower LTV.

This continuous, price-responsive LTV curve allows PredMart to offer competitive borrowing limits for high-confidence positions while protecting the pool from losses on risky collateral.

Oracle-Signed Price Feeds​

PredMart does not rely on on-chain price oracles (which can be manipulated or stale). Instead, the protocol uses a relay system where the PredMart backend fetches real-time prices from Polymarket's Central Limit Order Book (CLOB), signs them cryptographically, and submits them alongside user transactions. The smart contract verifies the oracle's signature and the freshness of the price data before executing any operation.

This design provides several advantages:

  • Real-time prices: Prices are fetched at the exact moment of the transaction, not from a potentially stale on-chain oracle.
  • Manipulation resistance: The oracle is the only entity that can sign valid price data, preventing users from submitting fabricated prices.
  • Freshness guarantees: The contract rejects price data older than 10 seconds, ensuring all operations use current market data.

Depth-Gated Borrow Caps​

To protect the pool from concentration risk, PredMart implements a depth gate system that limits how much can be borrowed against any single token. The borrow cap for each token is determined by the liquidity depth of its orderbook on Polymarket. Tokens with deep, liquid markets allow larger borrowing; tokens with thin, illiquid markets are more restricted.

This prevents a scenario where a large borrower takes on a massive position in an illiquid market that cannot be efficiently liquidated if the price drops.

Real-Time Liquidation Engine​

PredMart's backend maintains a real-time WebSocket connection to Polymarket's price feed. When the price of any collateral token drops enough to make a borrower's position unhealthy (health factor below 1.0), the liquidation engine automatically triggers a liquidation within seconds. A fallback REST-based polling system runs every 5 seconds in case the WebSocket connection is interrupted.

Automated Market Resolution Handling​

When a Polymarket market resolves (the outcome is determined), PredMart automatically handles all affected positions:

  • Won markets: The collateral shares can be redeemed for $1.00 USDC each. PredMart facilitates the redemption, repays any outstanding debt from the proceeds, and sends the surplus to the borrower.
  • Lost markets: The collateral shares become worthless. PredMart closes the position and absorbs any remaining debt as bad debt, which is socialized across all lenders in the pool.

Protocol Architecture​

PredMart's architecture spans three layers:

On-Chain Layer (Polygon)​

The PredmartLendingPool smart contract is the core of the protocol. It is an upgradeable contract (UUPS proxy pattern) that handles all financial operations. Key on-chain components include:

  • ERC-4626 Vault: Manages lender deposits, share minting/burning, and yield distribution.
  • Collateral Manager: Tracks per-user, per-token collateral deposits and borrower positions.
  • Interest Rate Model: Implements a kinked utilization-based interest rate curve with configurable parameters.
  • Liquidation Engine: Allows authorized liquidators to repay unhealthy debts and seize collateral.
  • Oracle Verifier: Validates cryptographically signed price and resolution data.
  • Timelock Governance: Protects sensitive parameter changes with a mandatory waiting period.

Backend Layer (Python/FastAPI)​

The PredMart backend runs on a GCP virtual machine and provides:

  • Oracle Service: Fetches real-time prices from Polymarket CLOB, signs them, and relays transactions to the blockchain.
  • Liquidation Bot: Monitors all positions via WebSocket and REST fallback, triggering liquidations when health factors drop below 1.0.
  • Event Indexer: Continuously indexes blockchain events (deposits, borrows, repayments, liquidations) and maintains a synchronized database.
  • API Server: Provides REST endpoints for the frontend to query pool statistics, user positions, lending history, and more.
  • Depth Sampler: Periodically samples Polymarket orderbook depth to compute borrow caps.
  • Resolution Monitor: Watches for market resolutions and processes affected positions.

Frontend Layer (React)​

The PredMart web application at predmart.com provides the user interface for all protocol interactions. Users connect their wallets via RainbowKit (supporting MetaMask, WalletConnect, and other providers), and interact with the protocol through a clean, intuitive interface.

Who Is PredMart For?​

Prediction Market Traders​

If you trade on Polymarket and want to amplify your positions, PredMart lets you use your existing shares as collateral to borrow USDC and buy more shares. This is the equivalent of margin trading in traditional finance — but built natively for prediction markets.

Yield Seekers​

If you hold USDC and want to earn passive yield, PredMart's lending pool offers competitive interest rates generated from real borrowing demand. Unlike many DeFi yield protocols that rely on token emissions or unsustainable incentives, PredMart's yield comes from genuine borrowing activity.

DeFi Power Users​

If you want to build automated trading strategies or integrate PredMart into your own applications, the protocol provides a fully documented smart contract interface, a comprehensive REST API, and standard ERC-4626 vault compatibility.

Security Model​

PredMart takes a defense-in-depth approach to security:

  1. Non-custodial smart contract: All funds are held by the contract, not by any individual or company.
  2. Oracle signature verification: All price data is cryptographically signed and verified on-chain.
  3. Timelock governance: Sensitive parameter changes require a mandatory waiting period.
  4. Dynamic risk parameters: LTV ratios adjust automatically based on collateral prices.
  5. Depth-gated borrow limits: Prevents concentration in illiquid markets.
  6. Real-time monitoring: Sub-second liquidation response via WebSocket price feeds.
  7. Emergency pause: The admin can pause the protocol in case of a critical vulnerability.
  8. Price drop guard: Automatic blocking of new borrows during rapid price crashes.

For a detailed breakdown of PredMart's security architecture, see the Security page.

Next Steps​