0.0.11 (2026-02-03)

Fixes

Improved shard distribution balance in rendezvous hashing

Fixes imbalanced shard distribution in rendezvous hashing by switching to a higher-quality hash function.

Problem

The previous implementation used DJB2 hash with XOR combination, which produced poor distribution across nodes. In production with 3 nodes and 2048 shards, this resulted in up to 11% imbalance (731 vs 655 shards per node).

Solution

• Added hash64() function based on xxHash algorithm with excellent avalanche properties
• Changed compute_runner_score() to hash the concatenated key directly instead of XOR-ing separate hashes

Results (3 nodes, 2048 shards)

Metric	Before	After
Distribution	731, 662, 655	689, 683, 676
Max difference	76 shards	13 shards
Imbalance	11.1%	1.9%

This achieves ~6x better balance with no performance impact.