also add lmdb/boltdb to that list. there seems to be a convergence around a certain feature-set for embeddable key/value stores: MVCC semantics and ordered keys.

https://charlesleifer.com/blog/completely-un-scientific-benc... does some basic performance comparisons for unqlite, vedis, dbm and kyotocabinet, leveldb, rocksdb, sqlite and redis.

As well as comparison to LMDB.