The main core of the Experimental Physics and Industrial Control System (EPICS) toolkit.
EPICS Base contains the build system and build tools, common and OS-interface libraries, Channel Access client and server libraries, static and run-time database access routines, the database processing code, and standard record, device and driver support.
The first operational version in the 3.15 series of EPICS Base was released in December 2014. Future versions in this series may contain minor functionality enhancements and bug fixes.
See the other EPICS Base projects here for the development version.