nessDB is an embedded key-value DBMS written in ANSI C with BSD license. It does not require any external dependencies and works in most POSIX systems.
As for storage engine, nessDB used LSM-tree (Log-Structured Merge Tree) in v1.8, Small-Splittable Tree (SST) in v2.0, and will use fractal-tree in v3.0. nessDB also used fractional cascading to speed up query.
https://github.com/BohuTANG/nessDB
https://github.com/BohuTANG/nessDB
https://github.com/BohuTANG/nessDB/wiki
Bohu Tang
2011
2016