@lyku/para-decimal

const rate = 0.0825d;                 // the literal → __paraDec("0.0825")
const tax = subtotal.times(rate);     // exact — no float drift, ever

Self-contained exact-decimal arithmetic — the runtime behind the Nd literal. A Decimal is { coef: bigint, exp: number }, so every operation that doesn’t divide is exact: 0.1d.plus(0.2d) is exactly 0.3, not 0.30000000000000004.

API

JS has no operator overloading, so arithmetic is explicit method calls — the visible seam is the point (you always know which numbers are exact):

a.plus(b)   a.minus(b)   a.times(b)   a.dividedBy(b, { precision, roundingMode }?)
a.eq(b)     a.lt(b)      a.lte(b)     a.gt(b)     a.gte(b)
a.toString()          // exact decimal string
a.toNumber()          // lossy escape hatch, explicit by design

Division is the one operation that can’t stay exact (1/3); it defaults to 20 significant digits, rounding half-even, both overridable. Everything else — sums, ledgers, tax lines, aggregation loops — stays exact at any magnitude, because the coefficient is a bigint.

When to reach for it directly

The Nd literal covers the common case (money, rates, measured quantities in .pts/.pui code). Import the package directly when you need to construct decimals from strings at runtime (user input, CSV columns, DB numeric values) rather than from literals — same type, same methods.

> Availability. The literal lowering ships with the language today > (ParaBun / para-transpile emit it, and the runtime carries the > implementation). The standalone npm release of @lyku/para-decimal is > pending the workspace split — until then, direct-import usage is > in-repo only.