NavLib

contracts/src/libraries/NavLib.sol — a pure library plus the IPriceOracle interface.

Fixed-point NAV math in USDG base units. No floating point. Mirrors the SDK's nav.ts. Multiplication precedes division to preserve precision; division truncates toward zero.

#Functions

#valuePosition(uiBalance, tokenDecimals, price, priceDecimals, usdgDecimals) → uint256

value = uiBalance × price × 10^usdgDecimals / (10^tokenDecimals × 10^priceDecimals)

Reverts ZeroPrice on price == 0.

#equity(cashUsdg, positionsValueUsdg, liabilitiesUsdg) → uint256

cash + positions − liabilities. (The vault guards the underflow case before calling.)

#navPerShare(equityUsdg, totalShares, sharePrecision) → uint256

equity × 10^sharePrecision / totalShares; returns 0 when there are no shares.

#sharesForDeposit(assetsUsdg, totalShares, equityUsdg) → uint256

Pro-rata assets × totalShares / equity; bootstraps 1

#assetsForRedeem(shares, totalShares, equityUsdg) → uint256

Pro-rata shares × equity / totalShares; 0 when there are no shares.

#IPriceOracle

interface IPriceOracle {
  function price(address token)
    external
    view
    returns (uint256 value, uint8 decimals, uint256 updatedAt);
}

The minimal oracle surface the vault needs. ChainlinkOracle implements it.

#Why a library

NAV is computed in three places — the vault (on-chain), the keeper (paper accounting) and the app (display). NavLib + sdk/src/nav.ts are deliberately the same five formulas with the same truncation rules, so all three agree bit-for-bit. The SDK page has the TypeScript twins: SDK → NAV math.