Have you heard of Kyoto and Tokyo Cabinet libraries? That's the first thing I think of when I think of a KV in C++: http://fallabs.com/kyotocabinet/ http://fal

Have you heard of Kyoto and Tokyo Cabinet libraries? That's the first thing I think of when I think of a KV in C++: http://fallabs.com/kyotocabinet/ http://fallabs.com/kyotocabinet/ http://fallabs.com/tokyocabinet/ http://fallabs.com/tokyocabinet/ https://en.wikipedia.org/wiki/Tokyo_Cabinet_and_Kyoto_Cabinet https://en.wikipedia.org/wiki/Tokyo_Cabinet_and_Kyoto_Cabine... (The names contain Cabinet but they aren't related to city/national governments.) I once played around with Kyoto in Lua but can't say anything good or bad about it's performance, scalability, etc. They have documentation and some presentation slides in English on their website and provide quite a lot of language bindings if you are interested.