Great writeup! Another way to query the DB are probabilistic filters. I wrote a Bloom filter based query API for this a while ago: https://github.com/adewes/ha

Great writeup! Another way to query the DB are probabilistic filters. I wrote a Bloom filter based query API for this a while ago: https://github.com/adewes/have-i-been-bloomed https://github.com/adewes/have-i-been-bloomed Very fast and highly space efficient as well, 17.000 requests per second on a conventional laptop with 1.7 GB memory required at a false positive rate of 1:1.000.000 (and no dependencies on databases or anything else).