If you control the HNSW implementation, it can definitely do pre-filtering. Vespa does it, and you can modify open source HNSW libs easily. I added pre-filterin

If you control the HNSW implementation, it can definitely do pre-filtering. Vespa does it, and you can modify open source HNSW libs easily. I added pre-filtering support to an internal fork of HNSWLIB last week, for example…