rust decimal — Exact Decimal Arithmetic Deep Knowledge : Use with technology: . Why Not f64 for Money Floating-point cannot represent most decimal fractions exactly. For money, this is unacceptable : rounding bugs become real losses, audit failures, regulatory issues. For Bitcoin specifically: always use for sats (1 BTC = 100,000,000 sats fits easily). For fiat conversions, multi-currency display, fee calculations involving rates → use . Setup Useful features: - — serialize as string (preserves precision in JSON) - — serialize as float (loses precision, but compatible) - — preserve via serde…