This may have been mentioned already, but the open-sourced LevelDB codebase is great. Original authors are Jeff Dean and Sanjay Ghemawat, so you know it's going

This may have been mentioned already, but the open-sourced LevelDB codebase is great. Original authors are Jeff Dean and Sanjay Ghemawat, so you know it's going to be really well written. https://github.com/google/leveldb https://github.com/google/leveldb