The kernel is stable since August 1997, with minor enhancements and bug fixes since. It has been tested on an R4600-based SGI Indy, on the Algorithmics P4000i prototyping board, as well as on the R4700-based U4600 system developed at UNSW as a research and teaching platform.

L4 is a general purpose microkernel implementing address spaces, threads and inter-process communication (IPC). Ports of L4 exist for other platforms also. See L4 Ports for details.

Present work on the kernel concentrates on performance issues, real-time capability, and further investigations of page table structures suitable for large, sparse address spaces. A new version of the kernel is under development where most of the VM management has been re-written. The new version will feature complete superpage support.

L4/Alpha authors

L4/MIPS was implemented by Kevin Elphinstone, a then PhD student at the University of New South Wales. Since late 1997, many students in the DiSy group have contributed bug fixes and minor enhancements.