acra

Database security suite. Database proxy with field-level encryption, search through encrypted data, SQL injections prevention, intrusion detection, honeypots. Supports client-side and proxy-side ("transparent") encryption. SQL, NoSQL. Maintained by cossacklabs on GitHub, where it has earned 1,491 stars from the community.

It's actively developed around encryption-server, encryption, crypto, and is a solid reference for anyone building with these tools.