ETHx

ETHx is Stader's liquid staked-ETH token.

ETHx is Stader's liquid staked-ETH token. No direct ETHx/USD Chainlink feed is used; this ICustomPriceFeed adapter combines Stader's exchange rate with an ETH/USD price read from the NAV's own primary feed. An independent cross-rate monitor feed (ETH/USD × ETHx/ETH, with a Chainlink ETHx/ETH leg) is registered as a divergence monitor — a market depeg flags ETHx irregular without moving its price. That cross-rate is ETHx's only monitor: the direct Redstone ETHx/USD monitor was removed with no replacement when Redstone retired its ETHx push feeds, and Chainlink publishes no ETHx/USD. The cross-rate survived because its rate leg could be migrated from Redstone to Chainlink's ETHx/ETH, so ETHx keeps its 250 bps divergence signal.

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

Source: ETHx_CustomPriceFeed.sol

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Approach

getExchangeRate() (StakePoolsManager) × ETH/USD.

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

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Price calculation

price = getExchangeRate() (18) × (ETH/USD) (8) / 1e18      // USD, 8 dec

Input	Source	Description
getExchangeRate	IStaderStakePoolsManager.getExchangeRate() (18 dec)	ETH per 1 ETHx
ETH/USD	NAV base — getPriceDataNoDivergence(WETH) (8 dec)	the NAV's primary WETH/USD price

The rate is read from Stader's StakePoolsManager and grows as staking rewards accrue. The constructor additionally requires the manager address to be a deployed contract (non-zero code.length). Output decimals are inherited from the ETH/USD feed (8).

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Constructor

constructor(
    address ethx_,
    address stakePoolsManager_,
    address nav_,
    address baseAsset_
)

Parameter	Description
ethx_	ETHx token address (also the supported underlying)
stakePoolsManager_	Stader StakePoolsManager (exposes getExchangeRate())
nav_	NAVCalculator (proxy) — supplies the base asset's USD price via getPriceDataNoDivergence
baseAsset_	The registered base asset whose USD price is read (WETH)

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Staleness

getLatestPrice() returns stale if getExchangeRate() returns 0, or if the NAV reports the base asset (WETH) stale — all its feeds stale. The base leg's updatedAt comes from the NAV's selected WETH feed. The rate call has no independent heartbeat.

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Chains

Deployed on Ethereum.