The lightweight, distributed relational database built on SQLite
Vitess is a database clustering system for horizontal scaling of MySQL
A Redis based, fully automated and scalable database cache layer
A modern replacement for Redis and Memcached
A multi-threaded, multi-database tcp-based database insertion app.
Active, high-performance open source database middleware
A web front end for an elastic search cluster
Online Table Clustering Tool for PostgreSQL
Open Design and Integration Environment
High-Availability JDBC
although fully functional, this is a pre-framework that you can extend