Primitives

The composable building blocks shared across analytics. Every primitive is allocation-free in steady state, single-writer per cell, and replay-deterministic.

Primitive	Purpose
Rolling window	Bounded ring used by every windowed statistic.
Percentile	P²-quantile sketch — constant memory, online updates.
Baseline comparison	Distribution-comparison helpers shared by the alert analytics.
Alert predicate	Z-score / ratio / threshold predicate vocabulary.
Technical indicators	EMA / WMA / VWAP — the operators used inside windowed analytics.