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v3.5.0Jun 27, 2026

DeFiMath v3.5.0 — Extended boundaries

Three input ceilings widened to the actual mathematical limit of each function. Same precision, same gas, no API change. The previous bounds were conservative defaults — chosen to match typical 2024 on-chain use. Long-dated insurance, RWA bond options, and primitives composing on top of sqrt over very large numbers now fit without recompiling.

sqrt: full FP18-safe range

SQRT_UPPER_BOUND on the sqrt function raised from 2^80 · 1e18 ≈ 1.21 × 10⁴² to ⌊(2²⁵⁶ − 1) / 1e18⌋ + 1 ≈ 1.158 × 10⁵⁹ — a ~10¹⁷× increase. The new ceiling is exactly the boundary where the FP18 scaling step x · 1e18 would overflow uint256; sqrt now exposes its full precision-safe domain to callers.

Options & Binary: MAX_EXPIRATION 2y → 32y

MAX_EXPIRATION in both the Options and Binary modules raised from 2 years to 32 years:

// Options.sol and Binary.sol
uint256 internal constant MAX_EXPIRATION = 32 * SECONDS_IN_YEAR + 1;

(Was 63072000 + 1.) timeToExp = 1,009,152,000 (exactly 32 years) is now accepted; anything above reverts with TimeToExpiryUpperBoundError. MAX_RATE = 400% and every other input bound is unchanged.

Why 32 years

The hard math limit is scaledRate = rate · timeYear < EXP_UPPER_BOUND ≈ 135.3 (that's where expPositive is precision-tuned). At rate = MAX_RATE = 4, the maximum allowable horizon is 135.3 / 4 ≈ 33.8 years. 32 years sits ~5% under that ceiling — wide enough to admit every realistic long-dated product, with margin against precision degradation at the corner. At the worst combined corner (rate = 400%, vol = uint64.max ≈ 1844%, T = 32y), both scaledRate = 128 and scaledVol = vol · √T ≈ 104 stay under 135.3.

Precision at the extended corners

Worst observed absolute error across the new extended-bound sweep (4y, 8y, 30y, 50y horizons; 1000% vol; 200% rate; far-OTM and deep-ITM strikes) on a $1,000-spot call: 5.9 × 10⁻¹² $ — over 20× under the standard MAX_OPTION_ABS_ERROR = 1.3 × 10⁻¹⁰ threshold.

Get it

npm install [email protected]