Module bucketing

Constants

BUCKET_COUNT

Functions

assign_bucket

Deterministic bucket assignment: sha256("{subscriber_id}:{seed}"), first 4 bytes read big-endian, mod BUCKET_COUNT. Must match the TS implementation byte-for-byte (same hash input, same byte order, same modulo) — this is the cross-language bucketing contract, verified against packages/shared/src/experiments/bucketing-vectors.json below.

select_variant_index

Weights are fractions summing to 1. Boundary must replicate JS Math.round (half-away-from-zero for positives = f64::round here).