Scallop app is a Sui lending interface for Scallop money markets

Scallop app is a wallet-connected interface for using Scallop, a DeFi money market built on the Sui blockchain. Through it, users supply assets to lending pools, receive sCoins that track their deposits, borrow against collateral through Sui object-based obligations, monitor supply APY and borrow costs, and manage liquidity without handing assets to a centralized account.

The Sui-native borrowing account behind every loan

The defining detail is the obligation system. Before borrowing, a user creates an Obligation object that records collateral and debt. Ownership is represented by an Obligation Key, which behaves like an NFT in the wallet. This fits Sui's object-centric design: the shared Obligation stores the position, while the key proves who has the right to change it.

That structure gives borrowers a clear way to separate positions. Scallop supports multiple sub-accounts under one Sui address, including the primary account, so a user separates a stablecoin borrow from a more volatile strategy instead of blending every debt and collateral choice into one position. Transferring an Obligation Key transfers control of the related obligation, so key handling matters as much as token handling.

How supplying assets turns into sCoins

Supplying starts with an asset pool. A lender deposits supported tokens into a pool used by borrowers, and the protocol records that deposit with sCoins, short for Scallop Market Coins. These tokens represent the claim on the underlying deposit plus accrued value from borrower interest. The balance does not need a manual reward claim for the basic lending position; the accounting happens through the market coin value.

In the Scallop app, that deposit-and-receipt model is easier to understand than raw smart contract calls. A user sees the market, the asset, the displayed supply APY, and the available liquidity before confirming through a Sui wallet. The asset remains governed by the protocol's smart contracts, and withdrawal depends on pool liquidity as well as the user's own position state.

Borrowing capacity, collateral weight, and borrow weight

Borrowing is controlled by two separate ideas. Collateral weight determines how much borrowing capacity a deposited collateral asset contributes. A highly liquid or lower-risk collateral asset receives more useful borrowing power than a volatile or constrained one. Borrow weight then adjusts the debt side, making some borrowed assets count as heavier debt because their price behavior creates more risk for the market.

A borrower in Scallop app therefore watches more than the nominal loan amount. The position depends on oracle prices, collateral parameters, borrow parameters, accrued interest, and the health of the obligation. When collateral value falls or debt value rises, the account moves toward liquidation. That mechanism protects pooled lenders by allowing unhealthy obligations to be repaid and collateral to be sold through the protocol's liquidation process.

Interest rates rise with utilization

Scallop uses utilization-based interest rate models. When borrowers use more of a pool's liquidity, borrow rates rise and suppliers earn more from the higher demand. When liquidity is plentiful relative to demand, borrowing becomes cheaper and supply returns fall. The protocol documentation describes a trilinear interest rate design, which means the curve changes across multiple utilization zones instead of moving in one simple line.

This matters for anyone comparing APY markets. A displayed supply APY reflects current pool conditions, not a fixed coupon. Borrow APR also changes as utilization changes. The useful reading is the relationship between liquidity, demand, and risk limits: a market with attractive supply yield but thin exit liquidity creates a different experience than a deeper market with lower displayed yield.

Starting with a Sui wallet, SUI gas, and bridged assets

Opening Scallop app begins with a Sui-compatible wallet. Common wallet choices in the Sui ecosystem include Sui Wallet, Suiet, Martian, OKX Wallet, Bitget Wallet, and other wallets that support Sui transactions. The wallet needs SUI for gas because every supply, borrow, repay, withdraw, bridge, and claim action settles as an on-chain transaction.

Assets arrive in two main ways. A user sends SUI from an exchange into a Sui wallet, or bridges supported assets such as WETH, WBTC, USDC, and USDT into Sui through bridge infrastructure exposed in the interface. Once funds are on Sui, the lending workflow is straightforward:

• Connect a Sui wallet and choose the relevant market.
• Supply an asset to receive the matching sCoin receipt.
• Create an obligation before opening any borrow position.
• Deposit collateral into the obligation and review borrowing capacity.
• Repay debt or withdraw collateral as the position changes.

Where SCA and veSCA fit into the experience

SCA is Scallop's protocol token on Sui, and veSCA is the vote-escrowed form created by locking SCA for a chosen duration. The longer lock produces more veSCA for a given amount, and the veSCA balance decays as the lock period runs down. The token design links protocol participation to incentives, fee discounts, referral tiers, and governance functions as the system matures.

On a practical level, Scallop app shows this side of the protocol alongside lending markets, which matters for users chasing liquidity mining rewards rather than only base borrow-and-lend interest. veSCA boosts apply to incentive programs, so two suppliers with the same deposit size see different reward outcomes when one also holds enough veSCA. The base market mechanics and the reward layer should be read separately.

Fees that affect borrowing, liquidation, and flash loans

That said, Scallop's fee model includes more than Sui gas. Borrowing fees apply when a loan is opened, with protocol documentation describing different rates for main assets versus emerging and isolated assets. Borrowing interest fees direct a portion of borrower interest to the protocol. Liquidations include a protocol fee, and flash loans use a separate percentage fee on the borrowed amount.

The interface also reflects Sui network costs and oracle-related costs for price data. These items are small compared with large positions, yet they matter for tiny transactions or frequent adjustments. Scallop app is strongest when the user reads the full transaction preview, not only the APY tile, because fees, health factor changes, and wallet approvals all shape the final action.

What users actually do with the markets

Supply markets suit users who want their idle Sui ecosystem assets deployed into a peer-to-peer lending pool. Borrow markets suit users who want liquidity while keeping exposure to collateral assets. A common pattern is supplying SUI or stablecoins, then borrowing another asset for trading, liquidity provision, or short-term working capital inside Sui DeFi .

Flash loans serve developers and advanced traders who need uncollateralized liquidity that begins and ends inside one transaction. Scallop also provides SDKs and programmable transaction block tools, so integrations build lending, borrowing, swaps, bridges, and liquidity operations into broader Sui applications. The same pools that appear in the user interface become composable building blocks for other on-chain workflows.

Risks that matter before opening a leveraged position

The main risk is liquidation. Borrowing against volatile collateral creates a moving account because prices, interest, collateral weights, borrow weights, and protocol limits all change the health of the obligation. A position with a thin buffer gets closed by the market faster than a position with extra collateral and a conservative debt size.

Smart contract risk, oracle risk, bridge risk, and liquidity risk also belong in the decision. Audits and bug bounty programs reduce some uncertainty, yet they do not remove the need to size positions around what happens during fast market moves. Isolated and emerging asset categories exist because not every market carries the same depth, volatility profile, or parameter treatment.

Aave, Compound, and Sui-focused alternatives

Users familiar with Aave or Compound will recognize the broad lending-market pattern: suppliers earn interest, borrowers post collateral, utilization affects rates, and liquidations protect pools. The difference is the Sui execution environment. Scallop's obligation keys, sCoins, Sui wallet flow, and Move-based architecture make the experience feel different from EVM money markets even when the economic logic is familiar.

Within Sui, alternatives include other lending or liquidity protocols rather than one direct clone. Choosing Scallop app makes the most sense when the priority is Sui-native lending, object-based position management, sCoin composability, and access to SCA or veSCA incentives. A user already committed to Ethereum mainnet lending compares it against Aave or Compound; a user operating primarily on Sui compares pool depth, supported assets, incentive design, and liquidation parameters across Sui DeFi venues.