- mapdb 2,125 MapDB provides concurrent Maps, Sets and Queues backed by disk storage or off-heap-memory. It is a fast and easy to use embedded Java database engine.
- JDBM3 266 Embedded Key Value Java Database
- mapdb-hz-offheap 38 Provides off-heap storage for in-memory datagrid build in Turkey
- HEALPix 8 Astronomical sphere pixelization improved with range trees.
- elsa 8 Java serialization, faster and space efficient version of ObjectOutputStream