Feature Request: See Interest Earned in Asset / USD when supplied to Lending Pool

[gordonkoehn]

Hi Scallop Team, I don't know if this is the right way or place to raise this, but nevertheless.

I enjoy Scallops's yields in the Sui Ecosystem. Interacting with app.scallop.io on mobile and web,

I'd like to see how much interest I have earned in absolute asset terms and USD equivalents.

Right now, one can only see the total balance of principal and interest. This means I always have to look up my principal investment.

Please let me know if this is to be raised elsewhere. I am interested in understanding why this is not there yet and what my difficulties/ misconceptions are.

You can adjust the issue or move as you see fit.

Kind Regards,

Gordon

[nathanramli]

Hi @gordonkoehn,
Did you want to access this value on the contract side or from the interface?

With our current contract structure, it’s not possible to implement this feature directly on-chain. However, if the information is intended to be shown on the dApp interface, we can use an indexer to track user data.

Explanation why we don't have interest accumulated of each user in our contract

When you lend, you receive sCoin in return. sCoin is an interest-bearing token — its value constantly increases relative to the underlying asset as interest accumulates.
Because of this, we don’t store specific user information in the contract when someone lends. What the contract does track is the available liquidity for borrowers, but not who the lenders are. sCoins aren’t bound to any specific user address.

As a trade-off, this means we can’t track lender-specific data like identities or individual contribution amounts.
On the bright side, this allows for high composability — integrations are more flexible, and users can freely trade their interest-bearing sCoins.
By trading sCoins with someone else, you’re essentially transferring ownership of your liquidity in the Scallop lending pool to that person.

If you’re familiar with LSTs (Liquid Staking Tokens), you can think of sCoin in a similar way.

When someone lends in Scallop, it’s like staking your tokens to a validator. As the validator earns rewards, those rewards are shared with all LST holders by increasing the exchange rate between the LST and the underlying token.

As an LST holder, when you redeem your tokens after rewards have been distributed, you receive a higher exchange rate than before — meaning you’ve earned a profit. However, with LSTs, there’s no record of how much your original principal was — the system only cares about the tokens currently held and their exchange rate.

This is exactly how lending works in Scallop. sCoin represents your position, and its value increases over time as interest accumulates, without tracking the exact principal or identity of the lender.

[gordonkoehn]

@nathanramli Thank you for taking the time to write this verbose explanation.

Apologies – I should have specified. Yes, I refer to the UX in the dApp. Logging into the app, I'd like to see my interest earned on the tokens supplied – separate from my principal supplied , i.e. 123 WAL principal + 4 WAL interestand perhaps, APY last month. That would make logging into the dApp more exciting i.e. immediatly see high yield materializing without checking my transaction list.

I understand the on-chain difficulty. I hadn't thought that through. It makes sense that interest-bearing tokens mean losing lender-specific data. Yet if otherwise possible on the frontend side, this would be a real addition to the UX. Easily seeing the yield is what users are used to on centralized venues and in traditional finance.

Feel free to close this issue as you see fit.