const UInt64:  brand(
  "UInt64",
  BigInt,
  (value) =>
    globalThis.BigInt.asUintN(64, value) === value
      ? ok()
      : err<UInt64Error>({ type: "UInt64", value }),
  (error) =>
    The value ${safelyStringifyUnknownValue(error.value)} is not a valid unsigned 64-bit integer (UInt64).,
) ;