sUSDS

Custom price feed for Sky/MakerDAO Savings USDS.

Custom price feed for Sky/MakerDAO Savings USDS. sUSDS is an ERC-4626 vault share that accrues value as the Sky Savings Rate (SSR) accumulates. The price is derived from the vault's current share-to-asset conversion rate multiplied by the Chainlink USDS/USD feed.

Source: sUSDS_CustomPriceFeed.sol

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Approach

sUSDS.convertToAssets(1 sUSDS) × USDS/USD (from the NAV's primary feed)

The USDS/USD term is sourced from the NAV's own selector — see Base/USD from the NAV's own selector.

sUSDS price feed — how its oracle inputs compose into a USD price, with the staleness gate.

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Price calculation

decimals = sUSDS.decimals()                       // vault share decimals
rate     = sUSDS.convertToAssets(10^decimals)     // USDS per 1 sUSDS (vault decimals)
price    = rate × USDS_USD / 10^decimals

Input	Source	Description
convertToAssets()	IERC4626(sUSDS)	USDS backing per 1 sUSDS share at the current SSR-accrued rate
USDS_USD	NAV base — getPriceDataNoDivergence(USDS) (8 dec)	the NAV's primary USDS/USD price

The ERC-4626 convertToAssets call returns the current exchange rate including all accrued Sky Savings Rate interest. The vault decimals are read once at deploy. Result carries the feed's 8 decimals. The USDS/USD term is read from the NAV's primary feed.

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Constructor

constructor(
    address sUsds_,
    address nav_,
    address baseAsset_
)

Parameter	Description
sUsds_	The sUSDS vault address (also used to read vault decimals)
nav_	NAVCalculator (proxy) — supplies the base stablecoin's USD price via getPriceDataNoDivergence
baseAsset_	The registered base stablecoin whose USD price is read (USDS); must equal the vault's asset() — reverts BaseAssetMismatch otherwise

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Staleness

The price is stale if the NAV reports the base asset (USDS) stale — all its feeds stale. The base leg's updatedAt comes from the NAV's selected USDS feed. The convertToAssets rate has no heartbeat — it is a live view on the ERC-4626 vault.

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Chains

Deployed on Ethereum mainnet only.