import type { Entry } from '../entry/entry.js';
import { type RollupDelta } from './rollup-store.js';
/**
 * Folds a batch of entries into additive rollup deltas, grouped by
 * `(type, floorToBucket(createdAt))`. Pure & deterministic:
 * - `count` = number of entries in the group,
 * - `sum`   = Σ durationMs (null treated as 0),
 * - `max`   = max durationMs (0 when every entry's durationMs is null),
 * - `histogram` = fixed-size latency-bucket counts; ONLY entries with a non-null
 *   `durationMs` increment a cell (null durations contribute to count/sum/max as
 *   before but NOT to the histogram). Memory-safe: a small fixed-length integer
 *   array per group, never any retained entry references.
 */
export declare function aggregateDeltas(entries: Entry[]): RollupDelta[];
//# sourceMappingURL=aggregate-deltas.d.ts.map