Mostly usearch since pgvector had some perf problems, though I use postgres during my ingestion stage since postgis is so good. I segment my hnsw indexes by multipe h3 levels.

Nice. And how do you handle candidates near H3 boundaries?

So I don't support queries with a radius larger than 50km (if an AI agent doesn't know where it's looking within 50km there usually is a context issue upstream), but i have a larger h3 index and a tighter h3 index. Then I have a router that tries to find the correct h3 indexes for each query. For some queries I'll need up to 3 searches, but most map to a single search. (sorry I probably won't be able to reply below here since the max hn comment depth is 4)

Reply to your comment below this (since hn limits comment depth to 4). The 40ms latency is an average but 90% of queries are getting routed to a single index, latency is worse when the routing goes to 3. Since I already batch the embedding generation I should be able to get hard queries down to like 50ms.

Makes sense. What about latency? for typical and hard queries