Scalars and expressions

Type	Source form	Rule
int	42	signed i64, checked arithmetic
float	3.5	finite f64 only
bool	true	comparisons and helpers produce bool
text	"hello"	UTF-8
uuid	typed string	key/index capable
bytes	typed hex	lowercase, even length
date	@2026-09-08	no implicit local time or calendar math
timestamp	value with Z or offset	exact instant
duration	30seconds	exact integer unit
decimal P S	decimal "19.90"	precision 1..38, never implicit rounding

Integer, float, duration, and same-type decimal operations are checked. Overflow, division by zero, or non-finite floats return E_ARITH. Values of the same decimal P S type support +, -, negation, and sum directly. Operations that may change scale name the result type and rounding mode explicitly; plain * and / never infer a decimal result:

derive {
  fee = decimal_mul amount (decimal "0.015") 12 2 "half_even"
  share = decimal_div amount (decimal "3") 12 2 "toward_zero"
  rounded = decimal_round amount 12 0 "half_up"
}

aggregate {avg_amount = decimal_avg amount 12 2 "half_even"} averages with the same rules. Modes are exact, toward_zero, away_from_zero, floor, ceil, half_up, and half_even; exact fails when rounding would be needed. Convert legacy text with decimal_parse and change scale exactly with decimal_rescale.

timestamp ± duration returns a timestamp and timestamp - timestamp returns a duration. Dates do not consult a clock or local timezone.

Boolean expressions support comparisons, !, &&, ||, contains, length, option helpers, and bounded any/all. Braces delimit multiline expressions; parentheses change precedence. Collection predicates use value -> expression, never paired pipes.

Indexed byte leaves are limited to 8192 octets, complete durable index keys to 64 KiB, and ordinary typed values to 16 MiB. Violations fail atomically.