it's a key value store based on fiatjaf's eventstore/badger it uses a custom query logic that is based on the design of REQ filters - it's a little complicated to explain it but it fits into about 80 lines of code

they work a bit like graphQL, except there is no negation, something that would be a great innovation... so for example, if ANY event IDs appear in a filter then there is a secondary filter that is applied after the first match... really it should have selectors for each field that add on in a filter chain, and there should be a negation to screen out matches as well as include them

but this is the state of it now... i understand how it works now so i could improve it but this will be something for later